Taxonomic and Distributional Studies on Herbaceous Endemics of Lateritic Rocky Outcrops of Goa and South Konkan

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TAXONOMIC AND DISTRIBUTIONAL STUDIES ON HERBACEOUS ENDEMICS OF LATERITIC ROCKY

OUTCROPS OF GOA AND SOUTH KONKAN

Thesis submitted to Goa University for the award of degree of

DOCTOR OF PHILOSOPHY

In

BOTANY

BY

RUTUJA R. KOLTE Department of Botany

Goa University Goa – 403 206

Under the guidance of Prof. M. K. Janarthanam

Department of Botany Goa University

Goa – 403 206

AUGUST 2020

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CONTENT

CERTIFICATE DECLARATION

ACKNOWLEDGEMENTS LIST OF TABLES

LIST OF FIGURES

LIST OF PHOTO PLATES

1. INTRODUCTION AND REVIEW OF

LITERATURE……….. 1 - 35 2. MATERIALS AND METHODS (INCLUDING

STUDY AREA)……… 36 - 50 3. RESULTS AND DISCUSSION………... 51 - 293

A. SYSTEMATIC TREATMENT……….. 52 - 224 B. ANALYSIS………. 225 - 293 4. CONCLUSION………. 294 5. SUMMARY……….. 295 - 297 6. BIBLIOGRAPHY………. 298 - 334

ANNEXURE 1 PUBLICATIONS

CERTIFICATES OF PAPER PRESENTATION

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CERTIFICATE

This is to certify that the thesis entitled "Taxonomic and distributional studies on herbaceous endemics of lateritic rocky outcrops of Goa and South Konkan", submitted by Miss Rutuja Rajendra Kolte for the award of the degree of Doctor of Philosophy in Botany, is based on her original and independent work carried out by her during the period of study, under my supervision.

The thesis or any part thereof has not been previously submitted for any other degree or diploma in any University or institute.

(Prof. M.K. Janarthanam)

Date:– Research Guide Place:– Department of Botany

Goa University Goa – 403 206

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DECLARATION

I hereby declare that the present thesis entitled "Taxonomic and distributional studies on herbaceous endemics of lateritic rocky outcrops of Goa and South Konkan" is my original contribution and the same has not been submitted on any previous occasion for any other degree or diploma of this University or any other University/Institute. To the best of my knowledge, the present study is the first comprehensive work of its kind from the area mentioned.

The literature related to the problem investigated has been cited. Due acknowledgements have been made wherever facilities and suggestions have been availed of.

Place:– (Rutuja Rajendra Kolte) Date:– Candidate

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ACKNOWLEDGEMENTS

This thesis has seen through to completion with the support and encouragement of numerous people including the experts in this field, wellwishers, friends, colleagues and various institutions. At the end of my thesis, I would like to thank all those people who made this thesis possible. It is a pleasant task to express my thanks to all those who contributed in many ways to the success of this study and made it a memorable experience for me.

At this moment of accomplishment, first I would like to thank to my guide, Prof. M. K. Janarthanam. This work would not have been possible without his guidance, support and encouragement.

I warmly thank to DRC members Prof. I.K. Pai (Zoology department) and Prof.

S. Krishnan (Head of the department), for evaluating my work time to time with critical comments.

I am extremely indebted to faculty members of Botany Department, Goa University, Prof. P.K. Sharma (Dean), Prof. B.F. Rodrigues (Former Head), Prof.

Vijaya Kerkar (Former head), Dr Nandkumar Kamat, Dr. Rupali Bhandari and Dr.

Siddhi Jalmi for their guidance and all non-teaching staff of the department for their assistance during course of my work.

No words are adequate to express my gratitude to Dr. Sharad Kambale who inspired me, guided me and encouraged me throughout my work.

I am thankful to Dr Kanchi N. Gandhi (Howard University, USA), for his valuable advice, critical comments and clarifying doubts of nomenclature.

I am thankful to Prof. S.R. Yadav for his guidance and encouragement.

I am thankful to the authorities of the herbaria, Blatter Herbarium, Mumbai (BLAT), Shivaji University Herbarium, Kolhapur (SUK) who have kindly allowed me to examine the specimens and literature.

I am indebted to my teachers and experts in various fields for their guidance, support, encouragement, for discussion, valuable suggestions and providing necessary literature: Dr. Surendra Thakurdesai, Dr. Vinod Kumar Gosavi, Dr. Arun Chandore, Dr. Prashant Pusalkar, Dr. Aparna Watve, Stefan Porembski, Dr. Mangal Patwardhan, Mr. Sharad Apte.

I express my sincere thanks to the people who helped me for local permissions, information, arrangement of various activities, accommodation and food during my field trips: Mr. and Mrs. Babu Gavade (Chaukul), Bhai Gavade (Chaukul), Mr.

Rupesh Gavade (Chaukul), Mr. Dinesh Dhond Sir (Chaukul High-school), Hemant Ogale (Amboli), Mr. Kaka Bhise (Amboli), Mr. Shivram Gavade (Forest Department Amboli), Mr. A.N. Narvekar Sir (Amboli), Mr. Manoj Prabhu (Loliem), Mr. Fransic

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Rebello (Loliem), Mr. Suryakant Gaonkar (Goa), Hanuman Gawas (Goa), Mr. and Mrs. Santosh Talekar (Talere), Mr. and Mrs. Dilip Talekar (Talere), Snehal Talekar (Talere), Manoj Talekar (Talere), Mrs. Saloni Gosavi (Nashik), MR. and Mrs Gorakh Ilhe (Nashik), Dr. Balkrishna Gavade (Kankavali), Dr. Nagesh Daptardar (Devgad), Dr. Shweta Valanju (Devgad), Vishal Magdum (Ratnagiri), Dr. Amit Mirgal (Ratnagiri), Mr. Akshay Dalvi (Kudal), Pradeep Uncle.

I am thankful to authorities of various organizations for providing necessary help: Malabar Nature Conservation Club (MNCC), Amboli, Mhadei Research Center (MRC), Vivekanand Environment Awareness Brigade (VEAB). I am also thankful to Grampanchayat Chaukul, and Forest department Amboli.

I express my thanks to Goa University for providing me financial support during my work and to attend International Botanical Congress which was held at China. I am thankful to Rufford organization for support and encouragement in the form of Rufford Small Grant to carryout project: Conservation of Chaukul plateau through community involvement.

I am thankful to my seniors and colleagues and friends from various universities and institutions for their guidance and help during my work: Dr Ravikiran Pagare, Dr. Anup Deshpande, Dr Mayur Nandikar, Dr. Gnanasekharan, Dr Ashish Prabhugokar, Dr Pratibha Jalmi, Dr Nisha Kevat, Dr Vivek Pandi, Ms. Prabha Pillai, Mrs. Pallavi Konge-Randive, Mrs. Abhipsa Mahopatra, Ms. Akshatra Fernandes, Mr.

Kiran Gaude, Ms.Vaishali Gaonkar, Mr. Vinayak Khanolkar, Ms. Annie Nadar, Mr.

Dhilan Velip, Mr. K.C. Kishor, Ms. Rutuja Palkar, Dr Vera Maria Da Costa, Ms.

Prabha Tiwari, Ms. Smita Srivastava, Ms. Shravani Korgaonkar, Ms Tanvi Prabhu, Ms. Sankrita Gaonkar, Ms. Apurva, Ms Maria, Ms. Aditi Naik, Ms. Sheela Pal, Ms.

Sujata Dabolkar, Ms. Ravina Pai and all other research scholars of our department.

Shivaji University: Dr. Avinash Gholve, Dr. Avinash Adsul, Mr. Jagdeesh Dalvi, Dr Sandeep Gawde, Ms. Vaishali Patil, Ms. Sayali patil, Dr Pradnya Yadav, Ms. Rupali, Ms. Pooja Mane, Mr. Rohit Mane, Sneha Brahmadande. Calicut University; Dr.

Manudev, Mr. Nikhil Krishna, Ms. Jeomole, Ms. Resmi Mr Drishya; Aboli Kulkarni, Ms. Sruti Kasana, Dr. Karan Rana, Mr. Devidas Borude, Mr. Nilesh Madhav, Mr.

Pratik (Rajaour), Dr. Amit Mirgal, Ms. Indu Yadav.

I am thankful to my friends for their continuous support and encouragement:

Shivali Naik, Jaykanth, Praveen, Dr, Shabnam, Dr. Jaya Sharma, Aishwarya, Divyarani, Mamata, Siddhi, Prachi, Anushri, Omkar and Gaurav.

I specially thank to my husband Mr. Rahul Prabhukhanolkar for his support, motivation, helping me during field works, discussions and advising during my work.

No words to express my gratitude towards my parents, brother and my in-laws for moral support.

Rutuja R. Kolte

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LIST OF TABLES

Table

No. Title Page

number 1. List of major works which listed endemic elements in Indian flora. 12 2. List of new herbaceous taxa published from rock outcrops of

Northern Western Ghats (1991 – June 2020) 28

3. Field trips carried out in study area from September 2015 to

December 2019. 42

4. Microhabitat classification for herbaceous vegetation of LROs of

Goa and South Konkan. 45

5. Comparative morphological account of A. caudatum and A.

leschenaultii. 55

6. Comparative morphological account of A. murrayi, A. tortuosum, A

neglectum and A. neglectum var. saivadasanii. 57 7. Comparative morphological account of A. sahyadricum and A.

ghaticum. 60

8. Comparative morphological account of I. ratnagirica and I. pallida. 66 9. Comparative morphological account of E. belgaumense and E.

ratnagiricum. 86

10. Comparative morphological account of E. dalzellii and E. fluviatile. 88 11. Comparative morphological account of E. fysonii and E.

cuspidatum. 92

12. Comparative morphological account of E. goaense sp. nov. and E.

rayatianum. 93

13. Comparative morphological account of E. kolhapurense andE.

parviflorum. 95

14. Comparative morphological account of E. lanceolatum and E.

balakrishnanii. 97

15. Comparative morphological account of E. sharmae and E.

robustobrownianum. 106

16. Comparative morphological account of D. blatteri and D. stapfiana. 131 17. Comparative morphological account of G. acuminata, G. acuminata

var. stocksii and G. acuminata var. woodrowii. 142 18. Comparative morphological account of G. goaensis and G. henryi. 145 19. Comparative morphological account of G. mysorensis and G.

forficulata. 150

20. Comparative morphological account of G. talbotii and G.

veldkampii. 156

21. Comparative morphological account of E. lawii and E. sessile. 194 22. Comparative morphological account of C. jainii and C. pusilla. 199 23. Comparative morphological account of U. malabarica and

U. lazulina. 215

24. Ccomparative morphological account of U. praeterita and U.

uliginosa. 216

25. Herbaceous endemics of LROs of study area and their synonyms (in

numbers). 229

26. Details of taxa with basionyms. 229

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Table

number 27. List of endemic taxa which were typified by later workers. 230 28. List of endemic taxa whose names/author names have been

corrected in the present study. 231

29.

List of endemic taxa taxa (i) collected from other than type locality and/or outside earlier known distributional range, and (ii) forming new records to the states of Goa, Maharashtra or Karnataka.

232 30. Systematic composition (according to APG IV) of herbaceous

plants of LROs of study area. 238

31. Order-wise distribution of number of families, genera, total taxa and

endemic taxa from LROs of study area. 246

32. Altitude-wise distribution of herbaceous taxa on LROs of study

area. 252

33. Overview of altitude-wise endemic species at different ranks. 254 34. Family-wise distribution of endemic taxa at different altitudes of

study area. 256

35. Proportion of herbaceous endemics at different plateaus of study

area. 259

36. List of endemic genera from LROs of study area. 261 37. Distribution of herbaceous endemics in different macrohabitats of

LROs of study area. 267

38. Distribution of herbaceous endemics in different microhabitats of

39. Overview of distribution of herbaceous endemics from LROs of

study area. 285

40. Details of herbaceous endemic taxa from study area which are

distributed either on north and south sides of study area. 286 41.

Details of herbaceous endemic taxa from LROs of study area having study area as southernmost (distributed on northern side of study area) or northernmost end (distributed on southern side of study area) of distribution range.

288

42.

Details of herbaceous endemics from LROs of study area which are restricted in-between north-south boundaries of study area (point distribution).

290

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LIST OF FIGURES

Figure

number 1. Rainfall pattern at Taleigao for 2016 - 2019 (North Goa district). 39 2. Rainfall pattern at Loliem for 2016 – 2019 (South Goa district). 39 3. Rainfall pattern at Amboli for 2016 – 2019 (Close to Chaukul,

Sindhudurg district of Maharashtra, high altitude). 40 4. Rainfall pattern at Devgad for 2016 – 2019 (Sindhudurg district of

Maharashtra, low altitude). 40

5. Schematic presentation of spatial distribution of allied taxa of

herbaceous endemics of LROs of study area. 227

6. Schematic presentation of spatial distribution of allied taxa found

on LROs of study area. 228

7. Distribution of orders, families, genera, total taxa and endemic

taxa in major clades of APG IV classification. 236 8. Percentage of herbaceous endemic taxa from LROs of study area

in major clades of APG IV classification. 236

9. Overview of systematic composition (according to APG IV) of

herbaceous plants of LROs study area. 237

10. Order-wise presentation of number of families, genera, total taxa

and endemic taxa of herbaceous taxa of LROs of study area. 247 11. Top ten families with maximum number of genera of herbaceous

plants from LROs of study area. 248

12. Top ten speciose families with herbaceous plants on LROs of

study area and their endemic components. 248

13. Top five speciose genera of herbaceous plants from LROs of study

area. 249

14. Top four endemic species rich genera of herbaceous plants from

15. Altitude-wise distribution of herbaceous taxa at different ranks. 252 16. Order-wise distribution of number of families, genera, total taxa

and endemic taxa at high altitude of study area. 253 17. Order-wise distribution of number of families, genera, total taxa

and endemic taxa at low altitude of study area. 253 18. Schematic presentation of altitude-wise list of endemic taxa of

study area. 254

19. Altitude-wise distribution of families of endemic taxa of study

area. 255

20. Top three endemic species rich families at high altitude and low

altitude of study area. 257

21. Top three endemic species rich genera at high altitude of study

area. 257

22. Top three endemic species rich genera at low altitude of study

area. 257

23. Schematic presentation of herbaceous endemics on three plateuas

of study area. 259

24. Locality-wise list of herbaceous herbaceous endemics (Chaukul,

Loliem and GU campus). 260

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Figure

number 25. Microhabitat-wise distribution of herbaceous plants on LROs of

study area. 265

26. Macrohabitat-wise distribution of herbaceous plants on LROs of

study area. 266

27. Number of macrohabitats and microhabitats shared by endemic

taxa. 266

28. Flowering phenological pattern in herbaceous plants from LROs

of study area. 273

29. Altitude-wise flowering phenological pattern in herbaceous plants

from LROs of study area. 273

30. Plant communities on LROs of study area. 274

31. Plant community-wise flowering phenological pattern in

herbaceous plants from LROs of study area. 274

32. Schematic presentation of types of spatial and temporal

distribution patterns 281

33. Schematic presentation of spatial and temporal distributional

pattern of herbaceous endemic taxa under 16 categories. 282 34. Altitude-wise distribution of herbaceous endemics of LROs of

study area. 285

35. Century-wise first publication of herbaceous endemic taxa of

study area. 293

36. Publication of herbaceous endemic taxa of study area according to

distribution pattern. 293

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LIST OF PLATES

Plate

No. Title After

page 1.

Study area: Goa and South Konkan:

a. Ratnagiri district; b. Sindhudurg district; c. North Goa district; d.

South Goa district

37 2.

Types of microhabitats: Open rocks (a - e)

a. Exposed rock surface; b. Lateritic graveled area; c. Rock crevices; d. Boulders; e. Cliff.

47

3.

Types of microhabitats: Cryptogamic mat covered surfaces (a - c) and water pools (d and e)

a. Boulders; b. Tree trunks; c. Rock surfaces d. Shallow seasonal ponds; e. Deep seasonal ponds

47

4.

Types of microhabitats: Soil covered surfaces (a - g)

a. Shallow open surfaces; b. Deep open surfaces; c. Water stagnant/marshy areas; d. Around bushes; e. Periphery of boulders; f. Along edge of water body; g. Along cliff.

47

5.

Types of microhabitats: streams (a and b) and other associated microhabitats to plateaus (c and d)

a. Temporary shallow streams; b. Seasonal deep streams; c.

Epiphytic; d. Undergrowth of forested areas

47

6.

Herbaceous endemic plants from LROs of Goa and South Konkan:

a. Trithuria konkanensis; b. Arisaema neglectum var. sivadasanii; c.

Wiesneria triandra; d. Iphigenia ratnairica; e. Habenaria suaveolens; f. Porpax filiforms (=Eria dalzellii); g. Chlorophytum gothanense; h. Dipcadi concanense.

52

7.

Herbaceous endemic plants on LROs of Goa and South Konkan:

a. Arisaema caudatum; b. A. sahyadricum; c. Iphigenia stellata; d.

Habenaria heyneana; e. Eriocaulon kolhapurense; f. E. rayatianum.

52

8.

Districtwise distribution of herbaceous endemic plants in Goa and South Konkan:

a. Trithuria konkanensis; b. Arisaema caudatum; c. A. neglectum var. sivadasanii; d. A. sahyadricum; e. Wiesneria triandra; f.

Aponogeton nateshii; g. Iphigenia ratnagirica; h. I. stellata; i.

Habenaria heyneana; j. H. suaveolens; k. Porpax filiformis; l.

Chlorophytum gothanense ;m. Dipcadi concanense; n. D. goaense;

o. Murdannia brownii; p. M. dimorpha; q. Curcuma scaposa.

82

9.

a. Dipcadi goaense; b. Murdannia brownii; c. M. dimorpha; d.

Curcuma scaposa; e. Eriocaulon anshiense; f. E. belgaumense; g.

E. dalzellii; h. E. eurypeplon.

82

10.

Herbaceous endemic plants on LROS of Goa and South Konkan:

a. Eriocaulon fysonii; b. E. goaense sp. nov.; c. E. lanceolatum; d.

E. parvicephalum; e. E. sedgwickii; f. E. sharmae.

92

11.

a. Eriocaulon anshiense*; b. E. belgaumense; c. E. dalzellii*;

d. E. eurypeplon; e. E. fysonii; f. E. goaense sp. nov.;

106

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Plate

page g. E. kolhapurense; h. E. lanceolatum; i. E. margaretae; j. E.

palghatense; k. E. parvicephalum; l. E. ratnagiricum; m. E.

rayatianum; n. E. sedgwickii; o. E. sharmae; p. E. tuberiferum.

12.

a. Cyperus kanarensis; b. Eleocharis konkanensis; c. Fimbristylis dauciformis; d. F. kernii subsp. ambolica; e. F. monospicula; f. F.

ratnagirica; g. F. simpsonii; h. Arthraxon jubatus; i. A. meeboldii; j.

A. raizadae; k. Bhidea burnsiana; l. B. fischeri*; m. Chrysopogon castaneus; n. Danthonidium gammiei; o. Dichanthium paranjpyeanum; p. Dimeria blatteri; q. D. stapfiana; r. D.

woodrowii*. (* Outside study area reported from other altitude)

134

13.

a. Garnotia arborum; b. Glyphochloa acuminata; c. G. acuminata var. stocksii; d. G. acuminata var. woodrowii; e. G. divergens; f. G.

goaensis; g. G. henryi; h. G. maharashtraensis; i. G. mysorensis; j.

G. ratnagirica; k. G. santapaui; l. G. talbotii; m. G. veldkampii; n.

Indopoa paupercula; o. Isachne borii; p. I. gracilis; q. Ischaemum bolei; r. I. yadavii; s. Jansenella neglecta; t. Nanooravia santapaui; u. Pogonachne racemosa.

170

14.

Herbaceous endemic plants on LROs of Goa and South Konkan;

a. Eriocaulon tuberiferum; b. Crotalaria lutescens; c. Ceropegia.

concanensis; d. C. mohanramii.

172

15.

Herbaceous endemic plants on LROs of Goa and South Konkan;

a. Flemingia gracilis; b. F. tuberosa; c. Geissaspis tenella; d.

Euphorbia concanensis; e. Rotala malampuzhensis; f. R.

pseudojuniperina; g. Sonerila scapigera.

184

16.

a. Impatiens kleiniformis; b. I. lawii; c. Neanotis lancifolia; d. N.

subtilis; e. Exacum lawii; f. Ceropegia attenuata; g. C. jainii.

198

17.

a. Crotalaria lutescens; b. Flemingia gracilis; c. F. tuberosa; d.

Geissaspis tenella*; e. Euphorbia concanensis; f. E. notoptera; g.

Rotala malampuzhensis; h. R. pseudojuniperina; i. Sonerila scapigera; j. Impatiens kleiniformis; k. I. lawii; l. Neanotis lancifolia; m. N. subtilis; n. Canscora shrirangiana; o. Exacum lawii; p. Ceropegia attenuata; q. C. concanensis; r. C. jainii; s. C.

mohanramii. (* outside study area reported from high altitude)

200

18.

a. Distimake rhyncorhiza; b. Lepidagathis clavata; c. L. keralensis;

d. L. prostrata; e. L. shrirangii; f. L. ushae; g Utricularia albocaerulea; h. U. malabarica (right side) and U. praeterita (left side).

214

19.

a. Utricularia purpurascens; b. Adenoon indicum; c. Senecio belgaumensis; d. Heracleum dalgadianum; e. Polyzygus tuberosus.

224

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Plate

page

20.

a. Cuscuta janarthanamii; b. Distimake rhyncorhiza; c.

Lepidagathis clavata; d. L. keralensis; e. L. prostrata*; f. L.

shrirangii; g. L. ushae; h. Utricularia albocaerulea*; i. U.

malabarica; j. U. praeterita; k. U. purpurascens; l. Adenoon indicum; m. Senecio belgaumensis; n. Heracleum dalgadianum; o.

Polyzygus tuberosus. (*outside study area reported from high altitude)

224

21. Succession on Chaukul lateritic plateau (2016-2017): Dry season

and pre-monsoon 278

22. Succession on Chaukul lateritic plateau (2016-2017): Monsoon

season 278

23. Succession on Chaukul lateritic plateau (2016-2017): Post-monsoon

and dry season 278

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CHAPTER 1 INTRODUCTION AND

REVIEW OF LITERATURE

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INTRODUCTION AND REVIEW OF LITERATURE

1 1.1: INTRODUCTION

1.2: REVIEW OF LITERATURE 1.2.A: Endemism

1.2.A.1: Evolution of the concept 1.2.A.2: Area and endemism

1.2.A.3: Patterns of endemism in different floras 1.2.A.3.1: Endemism in the Indian flora

1.2.A.3.1.a: Some important findings from endemic species rich groups 1.2.A.3.1.b: Endemism in the Western Ghats

1.2.A.3.1.b.i: Pattern of endemism in the Western Ghats 1.2.A.4: Models and techniques in endemism

1.2.A.5: Conservation of endemic taxa 1.2.B: Rarity

1.2.C: Rocky Outcrops 1.2.C.1: Inselbergs

1.2.C.1.1: Uniqueness of inselbergs

1.2.C.1.2: Plant composition, microhabitats and phenology 1.2.C.1.3: Adaptive traits

1.2.C.1.4: Factors controlling vegetation on inselbergs 1.2.C.2: Indian rock outcrops

1.2.C.2.1: Rocky plateaus

1.2.C.2.2: Environmental conditions

1.2.C.2.3: Plant composition, life-form and endemism 1.2.C.2.4: Phenology

1.2.C.2.5: Microhabitats

1.2.C.2.6: Threats and conservation

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2 1.1. INTRODUCTION

Endemic species richness is considered as “biological capital of the region or country” (Nayar, 1996). It is used as one of the criteria in identifying biodiversity hotspot and formulating world conservation strategies (Myers, 1988). According to Global Biodiversity Strategy conservation means, the management of human use of the biosphere for sustainable benefit to current generations and maintaining its potential to meet the needs of future generations. However, there is a tremendous pressure due to anthropogenic activities, on such endemic species rich areas (Cincotta et al., 2000) . The Western Ghats along with Sri Lanka is one of them, which is in the list of 36 biodiversity hotspots in the World (Hrdina & Romportl, 2017).

Diverse habitats are contributing to the endemic plants’ richness of the Western Ghats. One such habitat is Lateritic Rock Outcrops, which are mainly found in the Northern Western Ghats including narrow coastal belt and extending up to northern Kerala. They are unique ecosystems for endemic species richness (Joshi & Janarthanam, 2004; Lekhak & Yadav, 2012; Watve, 2013i). However, they are considered as barren lands and used for various activities such as mining, constructions, cashew and mango plantations, etc (Watve, 2013i; Thorpe & Watve, 2015).

There is an urgent need to plan management strategies to conserve habitats from changing land use and fragmentation (Watve, 2013i). Hence, from the conservation point of view, it is very important to identify the priority areas, which are rich in biodiversity and endemic species (Nayar, 1996). In addition to that, thorough understanding of endemic species’ taxonomy, phenology and distribution is essential. However, no adequate studies are available on phytogeography, phenology and morphological variations of endemic species of the Western Ghats. Hence, the work on "Taxonomic and distributional studies on herbaceous endemics of lateritic rocky outcrops of Goa and South Konkan" was undertaken.

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3 1.2: REVIEW OF LITERATURE

1.2. A: Endemism

1.2.A.1: Evolution of the concept

A. P. deCandolle (1855) first applied the concept "Endemic area" to describe the distribution of organism, which is defined as ‘an area of a taxonomic unit, especially a species which has a restricted distribution or habitat, isolated from its surrounding region through geographical, ecological or temporal barriers’. Adolph Engler (1882) appears to be the inventor of the dichotomy of old vs. new endemic. According to him, new endemics develop in different ecological niches or habitats through specialization from active genetic stock and they are also known as autochthonous endemics. Whereas, old or paleoendemics (relicts) are preservations of ancient stock, which were once widely distributed but now confined to a very limited portion of the former territory. Endemic taxa, which occur in disjunct areas are termed as ‘relict’ as their intermediate links were lost and new endemics are formed as secondary endemics (Drude, 1890). Similarly various work in subsequent years gave different names to paleoendemics as endemisme par conservation (Briquet, 1905), conservative (Diels, 1909), relict or ancient endemism (Herzog, 1926) and Paleoendemics (Chevalier & Guenot, 1925); whereas endemisme par novation (Briquet, 1905), progressive endemics (Diels, 1909), neoendemics (Braun-Blanquet, 1923; Chevalier

& Guenot, 1925; Herzog, 1926) to neo-endemics.

As concept evolved, various plant geographers started using the endemic concept in floristic studies, which resulted into some classical works and hypothesis, which helped to understand endemism and its types. Wallace (1876) seems to be the first biogeographer to employ endemism as an analytical, rather than a descriptive tool. He used the numbers of endemics as a measure of island age. He hypothesised that ‘the more endemic species that occurred on an island, the more archaic that island was likely to be’, the assumption being that ‘older islands had experienced a longer period of time for the occurrence of phylogenesis’. Wallace (1869) is the one who made clear distinction between oceanic island and continental islands. Wallace (1880) published a book ‘Island life’ which is considered as famous book in plant geography. Subsequently, Hemsley (1885) summarized the status of knowledge of various insular floras at that time. Based on endemics he divided islands into three groups: “(i) islands with large endemic elements (including

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endemic genera): their nearest affinities are not found in any one continent, (2) islands with small endemic elements (mostly in species form): derivatives can be easily traced and (3) islands containing no endemic elements”.

Willis (1922) quantified the idea of youthful endemics with ‘J’ – shaped or hollow curves. He also concluded that the age of taxon and size of area are interrelated. According to him, the endemics are frequently found upon mountains, upon islands, and in isolated pieces of country, or in regions in which dispersal is very slow, or hindered by surrounding barriers. The proportion of endemics increases with distance of an isolated island.

Endemics are distributed in "wheels within wheels". Endemic species belong to the larger genera and endemic genera from large families. However, there is no real difference in endemic and non-endemic species (or genera).

Wherry (1944) used the behavioral characters to distinguish endemics. According to him, the newly evolving endemics or neoendemics are ‘primary endemics’ and relicts or epibiotics as ‘secondary endemics’. The primary endemics increase its bulk and area and become ‘wide’ to reach their maximum phase and there after diminish or become relict or secondary endemics. He also suggested that, primary and secondary endemics can be distinguished by using distributional maps and relatives. Primary endemics are surrounded by its progenitor and secondary endemics are highly disjunct. He also mentioned the three types of endemics such as, (a) Environmentally repressed, (b) Genetically repressed and (c) Senescent, which are present in plants in cultivated form.

Cain (1944) identified two types of endemics, viz. (i) youthful species and (ii) epibiotics: which include relatively old and relict species. His work is considered as classic work on plant geography that explained the kinds and origins of endemic plant species. His three dicta on endemic species are:

1. “The endemism includes two types of organisms whose areas are confined to single regions: endemics, sensu stricto, which are relatively youthful species, and epibiotics, which are relatively old relic species. The concepts are applicable to groups other than species.”

2. “Youthful endemics may or may not have attained their complete areas by having migrated to their natural barriers. Epibiotics may, but frequently do not, contain the

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biotype richness which will allow or has allowed them an expansion of area, following their historical contraction of area.”

3. “The percentage and kinds of endemics in a flora are significant with respect to the history of the flora. A high degree of endemism is usually correlated with age and isolation of an area, and with the diversification of its habitats, as these factors influence both evolution (the formation of new endemics') and survival (the production of relic endemics').”

Stebbins (1950) proposes the gene pool/niche interaction theory to explain origin or rarity and endemism. His concept is based on the assumption of numerous causation.

According to his theory, combination of ecological factor which themselves are localized is the main factor which controls the distribution of endemics. He also mentioned, gene pool is another important component which controls the amount of variability and then led to the establishment of new population. He defined endemic as a ‘highly specialized species which has developed in a deep pool in a niche with a precipitous rim.

Further, Stebbins & Major (1965) recasted the Cain's two categories as paleoendemics and neoendemics. They also incorporated other factors to categorize the endemics such as the age of endemics, systematic position, cytological data (chromosome number and ploidal level) and mode of origin. According to Stebbins & Major (1965), most probably increasing constriction of specialized habitat over time results into a relict status. Whereas characters of neoendemics such as recent origin and splitting off from a parental entity may be passing for a future expansion of their range and gene pools. They also suggested that, as neo-endemic species are very sensitive, even for small shift can change local microclimatic conditions beyond the limits of tolerance of neo-endemic species, they must have either to migrate or to evolve new ranges of tolerance. This type of endemic species shows very limited migration and more fragmented population.

Occurrence of neo-endemic species is an indicator of climatic and environmental stress of particular region.

In between, Anderson (1937), Wulff (1943) and Senn (1938) suggested the use of cytological data to distinguish paleo and neoendemics. Using cytological data, Favarger &

Contandriopoulos (1961) reclassified endemics into following types: 1) Paleoendemics:

ancient, show little variability, ecologically specific, on the way of extinction, show relict

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distribution, have less polyploid, and their diploid ancestors are not known or vanished. 2) Schizoendemics: are resulted due to regular speciation or more or less synchronized divergence from a parent. Related schizoendemics may have the same number of chromosomes, but they can be of any age and degree of divergence from their parents. 3) Patroendemics: diploid endemics which give widespread polyploids and 4) Apoendemics:

polyploids arisen from their widespread diploid or lower polyploid parents. Whereas, Richardson (1978) predicted that all species will start as neoendemics and end as paleoendemics. In between holoendemism is also available. Under favorable conditions, neo-endemics behave as holoendemics and then they become paleoendemics. In this process they follow the steps viz.: origin, expansion, stabilization, diversification, migration, fragmentation, contraction and extinction.

According to Cronk (1997), the concept of palaeo-endemism is applicable to some oceanic island endemics. According to him, rather than in situ evolution of taxon, ex situ extinction of ancestral taxa or continental taxa gives taxonomic relicts. Obvious neoendemics will have their sibling species on continental areas. However, Myers & DeGrave (2000) suggested, all the taxa are endemic and occur in nested distributions at a range of spatial scales. According to them, the types of endemic such as neoendemics or paleoendemics proposed by earlier workers may not be of practical value in analytical biogeography. However, for interpreting the history of geographic areas, extinction mediated endemics, i.e. cryptoendemics and endemics which never had a significantly wider range, i.e. euendemics would be useful. They believed that, to distinguish these two types of endemics, only cladistic phylogeny provides a tool. They also suggested that, compared to families and genera, species are stenoendemic, hence they hold more biogeographical information. According to them, endemism originates in three different ways: 1) by extinction of populations in part of their range, 2) by range restriction through biogeographlc barriers (after anagenesis or phylogenesis) and 3) by jump dispersal followed by anagenesis or phylogenesis.

Recently, Cowling (2001) have proposed the classification based on range of occurrence. According to him, endemics can be classified as, (1) Point endemism: Species are restricted to live in small habitat range, (2) Biotope endemism/ Geographic endemism:

Species occur in geographically isolated mountain range, islands and river banks, (3) Biogeographic region endemism: Species are distributed in broad range of habitats (4)

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Regional endemism: Species are distributed in large phytogeographic region, and (5) Political area endemism: Species confined their distribution within political boundary of state, country, province and administrative unit.

Komposch (2017) have recently proposed classification of endemics for Austrian species. He has categorized endemics into 14 categories based on their distribution, viz; a) Austrian-endemic: a.1. locally endemic, a.2. regionally endemic a.3. nationally endemic;

(b) b Austrian-subendemic s. str.: b.1. locally subendemic; b.2. regionally subendemic; b.3.

nationally subendemic; (c) Austrian-subendemic s. l.: c.1. locally subendemic, c.2.

regionally subendemic, c.3. supranationally subendemic; (d) Eastern-Alps-endemic (e) Alps-endemic (f) Alps-subendemic (g) Boreo-alpine species (h) Arcto-alpine species.

However, paleoendemism and neoendemism are the two types, which are widely used to classify endemics, which are characterized by peculiar characters. Paleoendemics are characterized by having disjunct distribution (Kruckeberg, 2002), mostly have woody habitat (Stebbins & Major, 1965), low level of polyploidy or loss of genetic viability (Kruckeberg & Rabinowitz, 1985), usually belong to monotypic or oligotypic genera and monotypic families (López-Pujol et al., 2011) and also have fossil evidences (Stebbins &

Major, 1965; Bramwell, 1972). Whereas, neoendemics are closely related taxa occurring in same or adjacent region (Cowling & Holmes, 1992; Kruckeberg, 2002), polyploidy in nature with perennial herbaceous or shrubby habitats (Stebbins & Major, 1965), usually belongs to polytypic genera and forming a species complex with no clear taxonomic boundaries (López-Pujol et al., 2011), because of extensive chromosomal rearrangement and aneuploidy, the hybrids of their closely related species have low fertility (Nayar, 1980).

1.2.A.2: Area and endemism

In the study of biogeography, the identification of areas of endemism is an important and basic question (Henderson, 1991). According to Anderson (1994), in any specified area, percentage of endemics of particular taxonomic group such as genus or family changes if the number, either of endemic or of non-endemic species present in that area changes. He mentioned the possibilities of change in species number. They are: (1) Splitting of one species in an area into two species, this generally increases both the percentage of endemism and the species density in that area, (2) Expansion of the range of

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an endemic species beyond the area, this reduces the percentage of endemism but does not change the species density in this area, (3) Contraction of the extra limit of the range of a species whose range initially extended beyond the area. In this case, species becomes endemic to an area. This increases the percentage of endemism without any change in the species density in the area, (4) Extinction of an endemic species. This decreases both the percentage of endemism and the species density and (5) Extinction within a specified area of one of the non-endemic species. This increases the percentage of endemism and reduces the species density.

Linder (2001a) summarized areas of endemism as, ‘an implicit assumption in any area of endemism is that its biota has a single history and consequently that the biogeographical relationships of all the factors in the biota should be the similar’.

According to Noguera-urbano (2016) to test the relationship between areas of endemism using the phylogenetic relationship among taxa, some techniques such as Cladistic biogeography methods, have been proposed in the past. Authors also mentioned, the relationship between phylogeny and endemism have been poorly explored in biogeographic studies. They suggested for identifying areas of endemism and endemic taxa, the ‘congruence of distributional areas’ criterion to accept it as more or less conceptual foundation. And believed that, phylogenetic information is the good tool to understand and intereprete areas of endemism.

1.2.A.3: Patterns of endemism in different floras

According to Mason (1946), various categories of environmental factors or combination of conditions of environmental factors are responsible to restrict the range of some plant species. He also suggested that the occurrence of certain minerals and metals in the soil solution play an important role in geographic distribution of highly restricted plants. Mcglone et al. (2001) also observed that different terrains, climates and distinct environment play role in speciation.

According to Gentry (1986), the rate of speciation in less in the temperate regions as compare to the tropics. He also concluded that the tropical forests need much more attention than temperate zone ecosystems, because of their species richness and greater concentration of endemics. He considered human interference and habitat destruction these two factors for species which are having highly restricted distribution and considered

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them as "Anthropogenic" endemic. These endemics are often categorized as rare. Whereas, Huang et al. (2011) observed, endemics are more concentrated in temperate families and genera than cosmopolitan and tropical ones wherein the most primitive and derived groups have significantly higher endemism. They also observed that, distribution pattern of endemics varies from habit to habit. Proportion of Chinese endemic plants decrease with the increased latitude whereas proportion of endemics increase with altitude and they show unimodal curve. However, shrub, liana or vine and herb show a clear unimodal curve with an altitude. But proportion of endemic trees show sudden increase at ∼4000 m. Boden &

Given (1995) identified that the `Central Australian Mountain Ranges centre of plant diversity and endemism' due to its species and high concentration of endemic species;

however, according to Crisp et al. (2001) this area is having only species richness, not endemic richness. According to Linares-Palomino et al. (2010) the Montane seasonally dry forest regions at an altitude between 1,000 – 1,100 m was outstanding in terms of total species richness and number of endemics. Whereas, it was comparatively species poor at lowland areas of Ecuadorean and Peruvian and hills below 500 m altitude.

Linder (2001b) observed in sub-Saharan Africa, that south of the equator refugia for endemism are more generally distributed, whereas North of the equator, these refugia are sharply bordered and they are small, separated by large areas of very low endemism.

He also checked correlation among species richness and endemism, and latitude and rainfall. He suggested that species richness in sub-Saharan Africa influenced largely by modern rainfall, while palaeo-climatic fluctuations may be influencing endemism. Linder (2001b) observed, strong skewing towards the south in species richness and endemism, and believed that fluctuations in the Sahara might have influenced the modern distribution of plants in Africa. Noroozi et al. (2018) observed at Irano-Anatolian biodiversity hotspot, that due to high environmental heterogeneity and strong geographic isolation among and within mountain ranges, they are main centers of endemic species.

Hoffman & Cowling (1991) observed at lower Sundays River Valley, south-eastern Cape, endemic flora is well represented by succulents while endemic subtropical trees are poorly represented. They also believed that the sub-tropical thickets have strong Naroo- Namib phytogeographic links. Whereas, Burgess et al. (1998) studied the endemics of Coastal forests of eastern Africa. Their study showed, most of the narrow distributed endemics are found on the coastal forests. Most of the endemics of this forest show single-

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site endemism or scattered distribution. Historical climatic desiccation and current human destruction resulting into gradual more and more relict (and presumably extinct) nature in endemic species of these coastal forests regions. Hence, they interpreted these forests as a 'vanishing refuge'. According to study carried out by Crisp et al. (2001) on the Australian flora, major centers of endemism are near-coastal. They also observed that in some places, both species richness and endemism vary greatly across the continent.

Simmons et al. (1998) observed particularly on rocky substrate, congruence between species richness and endemism, is extremely high for most taxa, suggesting broadly similar speciation processes. However, overlapping of species rich areas and endemic areas is not consistent throughout the Namibia. In the flora of the western Mediterranean, Thompson et al. (2005) studied the general ecological differences among endemic and widespread congeners. They found that as compared to widespread congeners, endemic species occur in more rocky habitats, on steeper slopes. They also observed that, more open vegetation with lower species richness areas are favorable for endemism. Whereas study carried out by Stohlgren et al. (2005) at landscape of Grand Staircase–Escalante National Monument, Utah, USA concluded that primary hotspots of species richness, high endemism, and unique species groups are not co-located on the landscape. Hence, they advised to have much broader concept of ‘‘hotspots’’ to sufficiently preserve native plant species and the processes that foster persistence for conservation strategies.

Along an elevational gradient of Andean, Werff & Consiglio (2004) calculated the density of endemism and absolute number of endemic species among life forms and families. They found that, at mid-elevation (2000 – 3500 m) overall densities of endemics were 10–15 times higher than in the Amazonian lowlands (0–500 m). For herbs, shrubs, and epiphytes absolute numbers of endemic peaks were observed at 1500– 3000 m, while for trees, vines, and lianas it was at the lowlands (0–500 m). Whereas for 10 endemic species rich families, densities of endemics peaked at mid to high elevation (1500–4500 m); however, the absolute numbers of endemic species showed much disparity in the elevational distribution. They recommend that the size of protected areas should be increased from mid- to high altitude in the Andean slopes to protect highest density of endemics. They also suggested to focus on non-trees class for more studies since most endemic species belong to that class. According to Linder et al. (2005) , the orchid entities

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in Southern Africa are very unevenly distributed among the biomes. The Orchid endemics are concentrated in the habitats and biomes that have no equivalent in tropical Africa, whereas it is poorly presented in well developed habitats and biomes. They concluded that, endemics appear to be largely explained in terms of modern habitats.

Kessler & Kluge (2008) observed that the patterns of endemism are most probably determined by area (but inverse to species richness), topography, eco-climatic stability and taxon-specific ecological traits. Steinbauer et al. (2016) analyzed 32 insular and 18 continental elevational gradients from around the world. For testing the relationships between percent endemism and various factors such as elevation, isolation, temperature, area and species richness they used generalized linear model. They observed that in mountainous areas and across all elevations, topography-driven isolation increases speciation rates and it increases towards the equator. They also suggested that an increase in speciation caused by the isolating effect of topography might make a significant input to explain not only latitudinal gradients of beta and gamma diversity but also variations in those gradients with geological time.

1.2.A.3.1: Endemism in the Indian flora

Pioneer work on endemism in India was carried out by Chatterjee (1939). He compiled a list of dicotyledonous genera endemic to India, Burma and Sri Lanka as well as identified endemic species rich areas in Indian region. After that few studies were carried out to estimate plant endemism in India. Details of their works are given in Table 1.

Among them, Nayar (1980) is the first work to estimate endemic genera in Indian political boundary. According to his study, maximum number of endemic genera are concentrated in Indian Himalayan region (68 genera), followed by Peninsular India (56 genera) and then Andaman and Nicobar Islands (2 genera). However, according to recent literatures (Irwin

& Narasimhan, 2011; Singh et al., 2015) maximum number of endemic genera are concentrated in Peninsular India. Irwin & Narasimhan (2011) reduced the number of endemic genera to 49.

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Table 1: List of major works which listed endemic elements in Indian flora.

Sr.

No. Reference Endemism

Genera (Exclusive) Area - Taxa 1. Chatterjee (1939)

(Only dicotyledons)

India (including Burma) – 134

India – 6850 Himalaya – 3169 Peninsular India – 2045 Burma – 1071

2. Rao (1972) India, Myanmar & Sri Lanka – 164

3. Nayar (1980)

India – 141

- Indian Himalaya – 68

Peninsular India – 56 Andaman & Nicobar island – 2

4. Ahmedullah & Nayar

(1986) Peninsular India – 58 Peninsular India – 1931 5. Sarkar (1995) India – 142

6. Nayar (1996)

India (including

Himalayan region up to Tibet, China, Nepal &

Bhutan) – 147

India (including

Himalayan region up to Tibet, China, Nepal &

Bhutan) – 5727 Himalaya – 71 Himalaya – 3471 Peninsular India – 60 Peninsular India – 2015 Andaman & Nicobar

islands –

Andaman & Nicobar Island – 239

7. Ahmedullah (2000) India – 140

Himalaya – 66 Peninsular India – 59 Throughout India – 15 8. Mitra & Mukherjee

(2007)

India – 121

- Himalaya – 56

Peninsular India – 42 Andaman & Nicobar Island – 4

9. Irwin & Narasimhan (2011)

India – 49

- Peninsular India – 40

Indian Himalaya – 4 Andaman & Nicobar Island – 3

10. Singh et al. (2015)

India – 58 India – 4303

Peninsular India – 49 Peninsular India – 2592 Southern Western Ghats –

16 Western Ghats – 2116

Northern Western Ghats – 8

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Pioneer work on enumeration of endemic plants was done by Ahmedullah & Nayar (1986); they reported 58 endemic genera from Peninsular India. After a decade of this publication, Nayar (1996) provided the phyto-geographical distribution of endemic plants in India, Nepal and Bhutan. He dealt with 5727 endemic species. According to his study, there are three mega centers of endemism in India such as Eastern Himalaya (1808 endemic spp.), Western Ghats (1500 endemic spp.) and Western Himalaya (1195 endemic spp.). Based on endemic plants and their distribution, he identified 25 micro centers wherein conditions are favorable for endemic plants.

1.2.A.3.1.a: Some important findings from endemic species rich groups

According to Irwin & Narasimhan (2011), family Poaceae represents maximum number of endemic genera, which is followed by Apiaceae, Asteraceae and Orchidaceae.

These families also contribute to top 15 endemic species rich families listed by Singh et al.

(2015), viz., Poaceae, Orchidaceae, Leguminoseae, Rubiaceae, Acanthaceae, Asteraceae, Balsminaceae, Cyperaceae, Euphorbiaceae, Lauraceae, Apocynaceae, Lamiaceae, Melastomaceae, Zingiberaceae and Apiaceae.

The family Poaceae is an important family, which ranks first in Indian angiosperm flora. In India, Karthikeyan et al. (1989) enumerated c. 1200 species of grasses belonging to 268 genera. According to Jain (1986), Indian flora harbours about 350 grass taxa and nearly half of them are concentrated in Peninsular India. According to recent publication by Singh et al. (2015), a total of 335 taxa of this family are endemic to India. Total of 32 genera are monotypic, among them 13 are distributed in Indian territory (Rana & Ranade, 2009). Irwin & Narasimhan (2011) identified 49 endemic genera to India. Out of these, 27% of contribution is by family Poaceae. In Poaceae, most of the endemic taxa are from tribe Andropogoneae (Mehrotra & Jain, 1980). One of the important works from this group is on the genus Glyphochloa Clayton, which is having 11 species and four varieties and all of them are distributed in Peninsular India. Fonseca (2003) and Gosavi et al. (2016) have put light on evolution of this genus by recognizing two major lineages. One clade with single awned species is adapted to lower altitude whereas the other clade with double awned species is adapted to high altitude. In addition to that, floristic works, which specially focus on grasses (Gad, 2007; Potdar et al., 2012) have given more detailed information on distribution of grasses at regional level. According to Gad (2007), Goa

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harbours 44 Western Ghat’s endemic Poaceae members. Whereas, according to Potdar et al. (2012), 124 taxa, which are endemic to Peninsular India, are distributed in Maharashtra and among them 34 taxa are known only from Maharashtra.

Family Orchidaceae ranks 2^nd in India, as it shows maximum number of endemic taxa with 274 species. There are several works on enumerations, taxonomy and pictorial guides of Orchids, available from different regions of India. According to an estimation by Misra (2007), Orchidaceae represented 404 endemic species to Indian Political boundary, out of that 130 species are endemic to Peninsular India. In Peninsular India, about 60% of endemic orchids belong to genera Habenaria Willd., Bulbophyllum Thouars, Dendrobium Sw. and Eria Lindl. (Jalal & Jayanthi, 2012). Likewise, families such as Eriocaulaceae, represented by a single genus, i.e. Eriocaulon L. in India (Ansari & Balakrishnan, 1994, 2009), Lentibulariaceae (Janarthanam & Henry, 1992) and Euphorbiaceae (Balakrishnan

& Chakrabarty, 2007) show high concentration of endemism in Peninsular India.

Genus Impatiens (Balsaminaceae), ranks first with 169 endemic taxa in India. It is followed by Fimbristylis Vahl (75 endemic taxa), Eriocaulon (69 endemic taxa), Strobilanthes Blume (68 endemic taxa), Piper L. (46 endemic taxa), Crotalaria L. (44 endemic taxa), Ceropegia L. (44 endemic taxa), Ischaemum L. (40 endemic taxa), Syzygium Gaertn. (37 endemic taxa) and Leucas R.Br. (33 endemic taxa). Nevertheless, the distribution pattern changes from region to region (Nayar, 1996; Irwin & Narasimhan, 2011). Some of the endemic species rich genera such as Strobilanthes, Indigofera L., Alysicarpus Neck. Ex Desv., Ceropegia, Arisaema Mart., Litsea, etc. and endemic genera such as Adenoon Dalzell, Bhidea Stapf ex Bor, Indopoa Bor, Haplanthodes Kuntze, Polyzygus Dalzell, etc. are confined to Peninsular India, especially in the Western Ghats (Irwin & Narasimhan, 2011). Among all endemic genera of India, the genus Bentinckia Berry ex Roxb. shows unique distribution pattern. It is the only genus which shows disjunct distribution in Peninsular India and Andaman and Nicobar islands (Irwin &

Narasimhan, 2011). Till now Indian flora doesn’t have any endemic family.

1.2.A.3.1.b: Endemism in the Western Ghats

Blasco (1970) estimated that Nilgiri hills alone harbours 82 endemic species which are confined to that area. It is followed by Palani hills with 18 and Anaimalais with 13 endemic species. Western Ghats are considered to be the most important biogeographic

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zone as it harbours more number of endemics (Ramesh & Pascal, 1991). Subramanyam &

Nayar (1974) listed 20 genera and 84 species as endemic to Western Ghats. Henry et al., (1984) observed that the Agasthyamalai region in Triunelveli, Travancore hills has about 150 localized endemic species. According to Nayar (1996), Western Ghats is the one of the three mega centers for endemic plants in India. Eight out of 25 micro-endemic centers of India are from Western Ghats, which harbour high percentage of endemism. The two parts of Western Ghats, viz. northern Western Ghats (NWG) and southern Western Ghats (SWG) are two mega centers of Peninsular India wherein maximum number of endemic plants are distributed. The Western Ghats was ranking 2^nd in India with >1500 endemic species. However, according to recent studies by Irwin & Narasimhan (2011) and Singh et al. (2015), maximum number of endemic plants in India are concentrated in Western Ghats. According to Irwin & Narasimhan (2011), out of 40 endemic genera of Peninsular India, 36 are distributed in the Western Ghats. Singh et al. (2015) identified total 49 genera as endemic to Peninsular India, of which eight genera are restricted to northern Western Ghats and 18 genera to southern part of Western Ghats. Nayar et al. (2014) compiled 2253 Indian endemic taxa, which are distributed in Western Ghats. Whereas, according to Singh et al. (2015), Western Ghats harbor 2116 endemic taxa. In addition to that, state wise dominancy shows that the first three states are from Western Ghats viz., Tamil Nadu (410 taxa), Kerala (357 taxa) and Maharashtra (278 taxa).

Some enumerations are available wherein we get number of endemic taxa distributed in specific geographical area or states of the Western Ghats. Nayar et al. (2006) reported 851 endemic taxa from state of Kerala in compilation of flowering plants of Kerala. Whereas, Reddy et al. (2007) compiled total of 344 endemic taxa from the state of Karala. For northern Western Ghats, which is known as Sahyadri, Gaikwad et al. (2015a) provided a list of 159 endemic plants which are restricted to this region only. For the state of Goa, Singh (2016) published a list of endemic taxa based on literature survey wherein he has reported 357 taxa, which are endemic to Western Ghats or India. Datar &

Lakshminarasimhan (2011) have provided details of 127 endemic plants which they have reported from a protected area, i.e. Bhagvan Mahavir National Park. Whereas, Joshi &

Janarthanam (2004) studied 113 species in Goa which are endemic to Western Ghats. Both the studies by Joshi & Janarthanam (2004) and Datar & Lakshminarasimhan (2011) dealt with the distribution of endemic taxa in different habitats, their phenology, etc. Yadav

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(1997) compiled 545 endemic taxa for state of Maharashtra which are endemic to Peninsular India. Out of that, 125 are known only from Maharashtra. Later, Mishra &

Singh (2001) studied endemic and threatened plants found within the political boundary of Maharashta and provided detailed of descriptions, types, IUCN status, etc. According to their study, 215 endemic taxa are found in the state and out of that, 142 taxa are restricted to the political boundary of the state. Chandore (2015) compiled the list of endemic and threatened flowering plants occurring in Konkan region. In his study, he listed 100 plants.

A recent work on endemics of northern Western Ghats lists 181 endemics which are restricted to NWG and Konkan (Shigwan et al., 2020).

1.2. A.3.1.b.i: Pattern of endemism in the Western Ghats

Western Ghats is well explored by different workers in the form of revisionary, monographic studies (Janarthanam & Henry, 1992; Shanavas & Nampy, 2016; Kambale &

Yadav, 2019; Manudev et al., 2019). The Floras published in the region contributed to evaluate the number of endemic taxa to a greater extent (Dalzell & Gibson, 1861; Cooke, 1901; Talbot, 1909; Santapau, 1966; Vartak, 1966; Saldanha & Nicolson, 1976; Saldanha, 1984, 1996; Rao, 1985, 1986; Kulkarni, 1988; Manilal, 1988; Almeida, 1990; Vajravelu, 1990; Murthy & Yoganarasimhan, 1990; Lakshminarasimhan & Sharma, 1991; Deshpande et al., 1993; Kothari & Moorthy, 1993; Singh et al., 2001; Yadav & Sardesai, 2002;

Punekar & Lakshminarasimhan, 2011; Potdar et al., 2012) . All these works have enhanced the wealth of endemic taxa of the Western Ghats in the form of new taxa, addition of new families, new records, etc.

In Western Ghats, it has been observed that, endemic flora of northern part is rich in herbaceous form and in Southern part, tree flora is prominent (Ganesh et al., 1996).

Elouard et al. (1997) reported 48 % of tree endemism in the evergreen forest patch at Kodagu. This is one of the dense forest areas of the Western Ghats in Karnataka. Ghate et al. (1998), studied the average endemism for the evergreen forests and closed canopy evergreen forests of the Western Ghats. It is around 41% for evergreen forest and 55% for the closed canopy evergreen forest. Ramesh & Pascal (1997) brought out the atlas of distribution of endemic evergreen and semi-evergreen tree species of Southern Western Ghats. The evergreen forests in southern peninsular India are mainly restricted to the Western Ghats and the tree endemism varies with latitude. It shows its highest

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concentration in southern Western Ghats and gradually decreases towards northern Western Ghats (Pascal, 1988). He also suggested that, degree of endemism in Western Ghats have some pattern and it mainly depends upon two factors namely, (i) the increasing number of dry months from south to north and (ii) decrease in temperature with increase in altitude. Mesta (2008) obsereved, for many evergreen and endemic trees, the evergreen forests of the central Western Ghats act as a transition zone and form the northern limit.

Mesta & Hegde (2018) observed that evergreenness of the forest affect the composition of endemic tree population. Rajkumar (2001) worked on endemic tree genera of Western Ghats, which resulted in describing a new genus Agasthiyamalaia. He also observed that, all the genera except few are specific to their habitat.

Another important and dominant life form in Indian endemic flora is herbs (Rana &

Ranade, 2009; Irwin & Narasimhan, 2011; Singh et al., 2015). It is followed by Shrubs, trees and climbers (Singh et al., 2015). Joshi & Janarthanam (2004) observed that endemic flora in Goa is dominant in herbaceous form on lateritic plateaus. Subsequent studies carried out by Lekhak & Yadav (2012), Watve (2013i), Rahangdale & Rahangdale (2014), Datar & Watve (2018) made similar kind of observations and according to their study rocky outcrops in northern Western Ghats are rich in endemic plants, especially herbaceous flora.

Likewise some sporadic studies (Sukumaran & Jeeva, 2008; Sukumaran & Raj, 2008; Bhat & Kaveriappa, 2009; Chandran et al., 2010; Subbaiyan et al., 2015) are available on some habitat specific or forest specific or vegetation specific works such as Myristica swamps, Sacred grooves, cliffs, mountains, etc in which endemic plants are getting attention.

1.2.A.4: Models or techniques in endemism

Goldberg et al. (2005) tested their dynamic model with data on the biogeography and ages of extant genera of marine bivalves. They concluded that diversity in polar regions is due to the dispersal of taxa that evolved elsewhere, not because in situ origination-extinction dynamics. Whereas, Mishler et al. (2014) tested Australian Acacia as an example, for the application of phylogenetic methods, viz., relative phylogenetic diversity and relative phylogenetic endemism. According to their studies, areas of high species richness and species endemism are not necessarily areas of high phylogenetic