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Raja, Prakasam, Arulanandam, Lourdusamy John Peter, Soosairaj, Sebastian, Kabeer, Kadher Althaf Ahammed (2023): A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India. Adansonia (3) 45 (17): 285-291, DOI: 10.5252/adansonia2023v45a17

Justicia tamilnadensis P.Raja & Soosairaj, sp. nov. (Figs 1, 2; Table 1). Justicia tamilnadensis P.Raja & Soosairaj, sp. nov. is morphologically closely allied to Justicia salsoloides T.Anderson. It differs by its herbaceous, slender, purplish-green, glabrous, and angled stem, elliptic-oblong, lanceolate, glabrous, sub-sessile leaves, corolla pubescent on throat within and sub-terete capsules. TYPUS. — India. Tamil Nadu, Pudukkottai district, Poosathurai, (10°20’58”N, 78°47’22”E), c. 82 m, 11.X.2021, P. Raja & S. Soosairaj 4760 (holo-, RHT!; iso-, MH!). DISTRIBUTION, HABITAT AND ECOLOGY. — Justicia tamilnadensis sp. nov. is presently known only from the type locality where less than 20 individuals have been observed in open places in Vellar river bed at elevations of 70-85 m and associated with Fimbristylis falcata (Vahl) Kunth, Platostoma menthoides (L.) A.J.Paton, Evolvulus alsinoides (L.) L., Dyschoriste madurensis (Burm.f.) Kuntze, Eragrostis viscosa (Retz.) Trin., Euphorbia corrigioloides Boiss., Leucas diffusa Benth., Curculigo orchioides Gaertn., Cyanotis cristata (L.) D.Don, Vachellia leucophloea (Roxb.) Maslin, Siegler. & Ebinger and Melanocenchris monoica (Rottler) C.E.C.Fisch. PHENOLOGY. — Flowering and fruiting were observed from July to December. ETYMOLOGY. — The specific epithet tamilnadensis refers to one of the south Indian states Tamil Nadu from where the specimens were collected. CONSERVATION STATUS. — Justicia tamilnadensis sp. nov. was observed at only one location which is fragmented by transportation. The total population of this species is enumerated to be less than 20 individuals, and based on the field observation, the conservation status of the species has been evaluated accordingly. We have been surveying the entire Pudukkottai district and the surrounding regions since 2012. And from the entire study in the past decade, it was noted that the proposed species is found only in that specific location (Fig. 3). The geographic range for the Area of Occupancy (AOO) is c. 0.5 km ² and the distribution is limited to the type locality (IUCN 2022). Urbanization, transportation and expansion of the highly invasive Prosopis juliflora (Sw.) DC. threatens the population of this species. Hence, this species is classified in criterion B (AOO) under B2a and B2b and criterion D (number of mature individuals is less than 20) as well to meet the criteria for the Critically Endangered B2ab (ii,iii,v); D. ADDITIONAL SPECIMEN EXAMINED. — India. Tamil Nadu, Pudukkottai district, Poosathurai, (10°20’58”N, 78°47’22”E), c. 80 m, 09.X.2022, P . Raja 4766 (RHT!). DESCRIPTION Prostrate herb, 200-300 mm long; rootstock woody with fleshy roots. Stem prostrate, angled, slender, glabrous, bearded at nodes. Leaves sub-sessile, 9-35 × 3-6 mm, subcoriaceous, elliptic to oblong, opposite, cuneate at base, margins entire on young leaves and occasionally margins undulate on mature leaves, obtusely acute at apex, mid nerve prominent, lateral nerves 3-4, obscure. Inflorescence sub-terminal and terminal spikes, 15-50 mm long, loosely arranged, peduncle 4-10 mm long. Bracts linear-lanceolate, 5-9 × 2-3 mm, base truncate, margin entire, apex acute, ciliate at base. Bracteoles 2, lanceolate, 10-12 × 1.5-2 mm, 3-nerved, nerves obscure, base truncate, margin entire, ciliate at base, acute at apex. Flowers 1 cm long; calyx lobes 5, equal in length, 5 × 1 mm, narrow, linear, cuneate at base, acute at apex, pubescent; corolla 1 cm long, pubescent without; corolla tube 5 mm long, pubescent in throat; bilabiate, upper two-lobed, lobes connate except tip, lower broadly 3-lobed, mid lobe broader than lateral lobes, 4 × 3 mm, purplish inside, lateral lobes 4 × 2 mm, white inside. Stamens 2, exserted; filaments 5 mm long, glabrous; anthers 2-celled, pubescent on upper anther cell, 3 mm long with 1 mm appendage on lower anther cell. Pistil 8 mm long, ovary 2 × 1.5 mm, ovules 4, style slender, 6 mm long, pubescent on basal half, stigma simple. Capsule 12-15 × 5 mm, sub-terete, white tomentose without, shortly mucronate at apex. Seeds 3-4, echinate. TAXONOMIC COMMENTS Justicia tamilnadensis sp. nov. and J. salsoloides are restricted in distribution (Carnatic regions of Indian Peninsula). In the field, the habit of J. tamilnadensis closely resembles to that of Lepidagathis cristata Willd. and it could be mistaken in the absence of inflorescences. The rootstock of J. tamilnadensis resembles that of the Justicia trinervia Vahl. There are about 5-7 fleshy roots per plant. Each root is about 100-160 mm long and 2-3 mm wide and deeply rooted to the barren or gravel soil up to 200 mm in depth. The tuberous root system enables the persistent stem to tolerate the dry season., Published as part of Raja, Prakasam, Arulanandam, Lourdusamy John Peter, Soosairaj, Sebastian & Kabeer, Kadher Althaf Ahammed, 2023, A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India, pp. 285-291 in Adansonia (3) (3) 45 (17) on pages 286-289, DOI: 10.5252/adansonia2023v45a17, http://zenodo.org/record/8135393, {"references":["IUCN 2022. - IUCN Red List Categories and Criteria. Version 2022 - 1. https: // www. iucnredlist. org"]}

KEY TO THE GENUS JUSTicia L. FROM TAMIL NADU, INDIA 1. Calyx lobes 5............................................................................................................................................... 2 — Calyx lobes 4............................................................................................................................................. 14 2. Shrubs or undershrubs................................................................................................................................ 3 — Erect or diffuse herbs................................................................................................................................. 12 3. Anther cells minutely apiculate at base........................................................................................................ 4 — Anther cells with prominent white appendage at base................................................................................. 5 4. Inflorescence capitate.................................................................................. J. beddomei (C.B.Clarke) Bennet — Inflorescence spikes.................................................................................................................. J. adhatoda L. 5. Capsule 2-2.5 cm long................................................................................................................................ 6 — Capsule less than 2 cm long........................................................................................................................ 7 6. Erect shrubs. Leaves 6-9 cm broad................................................................................... J. santapaui Bennet — Procumbent undershrub. Leaves 0.5-1.5 cm broad.......................... J. nilgherrensis (Nees) Wight ex C.B. Clarke 7. Leaves less than 3 cm long........................................................................................................................... 8 — Leaves more than 5 cm long........................................................................................................................ 9 8. Bracts elliptic, acute.................................................................................................. J. salsoloides T.Anderson — Bracts orbicular or obcordate, short-apiculate............................................................... J. tranquebariensis L.f. 9. Capsule pubescent..................................................................................................................................... 10 — Capsule glabrous........................................................................................................... J. gendarussa Burm.f. 10. Seeds spinulose or echinate when wetted................................................................................................... 11 — Seeds softly round-tuberculate when wetted.............................................................. J. wynaadensis B.Heyne 11. Bracts white with green nerves; bracteoles similar....................................................................... J. betonica L. — Bracts not as above; bracteoles different, often absent............................................................ J. glauca Rottler 12. Leaves more than 5 cm broad................................................................................................. J. scandens Vahl — Leaves less than 1 cm broad....................................................................................................................... 13 13. Bracts white with green nerves. Seeds tuberculate when wetted............................................. J. trinervia Vahl — Bracts not as above. Seeds echinate when wetted.......................... J. tamilnadensis P.Raja & Soosairaj, sp.nov. 14. Spikes stout, cylindric............................................................................................................................... 15 — Spikes slender, linear................................................................................................................................. 18 15. Subshrubs or undershrubs; branchlets somewhat woody........................................................................... 16 — Herbaceous; branchlets slender.................................................................................................................. 17 16. Bracts with bulbous based white hairs. Capsule pubescent.......................................... J. neesii Ramamoorthy — Bracts not as above. Capsule glabrous........................................................... J. latispica (C.B.Clarke) Gamble 17. Spikes up to 3 cm long......................................................................................................... J. procumbens L. — Spikes more than 5 cm long................................................................................................ J. simplex D.Don 18. Calyx lobes obtuse at apex................................................................... J. quinqueangularis J.Koenig ex Roxb. — Calyx lobes acute at apex........................................................................................................................... 19 19. Bracts and bracteoles ovate.................................................................................................... J. diffusa Willd. — Bracts and bracteoles lanceolate................................................................................................................. 20 20. Seeds tuberculate.......................................................................... J. prostrata (Roxb. ex C.B.Clarke) Gamble — Seeds papillae............................................................................................................................................ 21 21. Leaves ovate-elliptic or linear-lanceolate, acute, glabrous........................................................... J. vahlii Roth — Leaves ovate or orbicular, obtuse, strigose above, villous beneath......................... J. nepalensis V.A.W.Graham, Published as part of Raja, Prakasam, Arulanandam, Lourdusamy John Peter, Soosairaj, Sebastian & Kabeer, Kadher Althaf Ahammed, 2023, A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India, pp. 285-291 in Adansonia (3) (3) 45 (17) on page 290, DOI: 10.5252/adansonia2023v45a17, http://zenodo.org/record/8135393

Lepidagathis decumbens N. Dhatchan. & S. Soosairaj, sp. nov. (Fig. 1; Table 1). Lepidagathis decumbens sp. nov. resembles L. diffusa C.B. Clarke, but differs in having erect and decumbent habit, short internodes, long unilateral spikes, multicelled glandular hairs, sericeous floral parts and ovate-suborbicular seeds (Table 1). TYPE MATERIAL. — India. Tamil Nadu, Dharmapuri district, Thippampatti village, 12°14’53.304”N, 78°16’31.980”E, alt. c. 358 m, 25.X.2013, N. Dhatchanamoorthy 1295 (holo-, HIFP! • iso-, RHT!). ETYMOLOGY. — The species epithet “ decumbens ” describes the erect and geniculate habit of the plant. DISTRIBUTION. — Lepidagathis decumbens sp. nov. is endemic to Dharmapuri district of Tamil Nadu, South India. PHENOLOGY. — Flowering and fruiting from October to January. ECOLOGY. — Dry, red, barren and gravel mixed soils at an elevation of 300-400 m a.s.l. Associated with Andrographis serpyllifolia (Vahl) Wight, Aristida hystrix L.f., Corbichonia decumbens (Forssk.) Exell, Cyanotis tuberosa (Roxb.) Schult. & Schult.f., Indigofera cordifolia Roth, I. linnaei Ali, Mollugo stricta L. Oldenlandia umbellata L., Oropetium thomaeum (L.f.) Trin., Senna italica Mill. and Tribulus subramanyamii P.Singh, G.S.Giri &V.Singh. CONSERVATION STATUS. — This species occurs in an area of only about one hectare which lies between the segments of Eastern Ghats. The population has about 50 mature individuals, there is a possibility that the species may occur in nearby areas with similar ecological niches. However, these habitats are yet to be explored. The species is currently categorized as ‘Data Deficient’ following IUCN (2020) criteria and categories. ADDITIONAL SPECIMEN EXAMINED. — India. Tamil Nadu, Dharmapuri district, Thippampatti village, 12°14’53.304”N, 78°16’31.980”E, 30.XI.2015, N. Dhatchanamoorthy, P. Raja & S. Soosairaj 2125 (SJC). DESCRIPTION Erect-decumbent herb, perennial, with woody rootstock; branches up to 30 cm long, stem terete, young branches purplish, scabrid-glabrescent; internodes up to 1 cm long. Leaves opposite, linear-oblong to lanceolate, 0.8-2.5 × 0.3-0.5 cm, sessile, attenuate at base, entire at margins, apex curved and spiny; lateral nerves 3-5, prominent at abaxial surface, indistinct on adaxial surface, scabrous hairy on both sides, leaf scars prominent. Inflorescence axillary, spike unilateral, 3-6 × 1-1.5 cm. Bracts lanceolate, 1.2 × 0.3 cm, truncate at base, acute-acuminate at apex, spiny, outer surface glandular sericeous, inner surface sericeous, margin with long hispid hairs in lower 2/3, scabridulous at apex, midnerve prominent. Bracteoles lanceolate, 10 × 2.8 mm, acute-acuminate, glandular sericeous, midnerve prominent, laterals actinodromus, spiny at apex. Calyx 5 lobed, 8.5-9 mm long, minutely mucronate-spiny at apex, outer surface glandular sericeous, inner surface sericeous; posterior sepal broader, lanceolate, 8.5 × 3.5 mm, acute-acuminate; anterior sepals 2, connate up to middle, lanceolate, 8.5 × 1.5 mm; lateral sepals 2, linear, 8.5 × 1.2 mm, smaller than the others. Corolla white, c. 1.4 cm long, 1 cm across, hispid on outer surface except at base; sparsely hispid inside, purple with yellow spots along the ribs, lobes 5, glabrous inside, upper 2 lobes connate, obtuse, emarginate, lower 3 lobes, median broader than the lateral, obtuse, emarginate, margins sinuate, lateral lobes obtuse. Stamens 4, didynamous, dorsifixed, filament 2-3.5 mm long, sparsely glandular; anthers ovoid-oblong, c. 2 mm long, bearded, pollen 3-colporate, 41.81-48.85 × 28.22-32.26 µm, exine thin, c. 3.52 µm, reticulate. Disk annular; ovary ovoid, c. 1.2 × 1 mm, glabrous; 2-locular; ovules 2 in each cell; style slender, 6 mm long, hispidglandular at base; stigma slightly bifid, glabrous. Capsules shorter than calyx, ovate-oblong, c. 6 × 4 mm, glabrous. Seeds 2, ovoid-suborbicular, c. 3.5 × 3 mm, densely short mucilaginous hairy. TAXONOMIC NOTES The distinguished characters between the species were compared (Table 1) with their images (Fig. 2). Lepidagathis diffusa is a prostrate herb, with up to 3 cm long internodes, leaf nerves prominent on both surfaces, spike dense, ovoid-oblong at upper axils, and the seeds are oblong with long mucilaginous hairs whereas the new species is erect-decumbent herb, with up to 1 cm short internodes, leaves linear-oblong and nerves indistinct on adaxial surface, spike oblong (unilateral) up to 6 cm long at leaf scar axils, floral parts glandular sericeous, and the seeds are ovoid-suborbicular with short mucilaginous hairs (Fig. 1). Anatomically, leaves of Lepidagathis diffusa have simple and non-glandular hairs, cystoliths on both surfaces, anisocytic and diacytic types of stomata. The cross section (CS) of stem shows vascular bundles (VB) surrounded by 2 layers of sclerenchyma cells, uniseriate medullary rays, absence of intra-xylary phloem and presence of acicular crystals at pith. Anatomy of L. decumbens leaves shows simple and four lobed glandular foliage hairs, cystoliths occur only on abaxial surface, epidermal peel has only diacytic type of stomata. The CS of stem shows VB surrounded by 3 layers of sclerenchyma cells, uni- and biseriate medullary rays, presence of intra-xylary phloem, and absence of acicular crystals (Fig. 3; Table 2) at pith. The SEM images of seeds from the two species clearly represented the difference in size and shape, particularly the base of seeds and the length of hydrophilic hairs (Fig. 4). In all, clear differences in morphology, anatomy, reproductive features and SEM images are strongly evidenced to confirm this Lapidagathis was new and named as L. decumbens.

KEY TO THE GENUS LEPIDAGATHIS WILLD. FROM TAMIL NADU 1. Prostrate-decumbent herb, capsule 2-seeded................................................................................................ 2 — Erect subshrub, capsule 4-seeded................................................................................................................. 8 2. Leaf margin or apex spinous tipped............................................................................................................. 3 Leaf margin entire or toothed, apex mucronate........................................................................................... 4 3. Leaves lanceolate, margin entire, one spine only at apex.......................................... L. spinosa Wight ex Nees — Leaves ovate-oblong, margin and apex spinous tipped....................................................... L. barberi Gamble 4. Spike aggregated only at lower nodes........................................................................................................... 5 — Spike at axils of leafy and leafless stem......................................................................................................... 7 5. Leaves> 3 cm long, lateral nerves 5-7 pairs.................................................................. L. hamiltoniana Wall. — Leaves ........................................................ L. mitis Dalzell — Leaves glabrous on both sides, margin entire to toothed....................................................... L. cristata Willd. 7. Spike globose-ovoid, internodes long to 3 cm................................................................ L.diffusa C.B. Clarke — Spike elongate and unilateral, internodes short to 1 cm......... L. decumbens N. Dhatchan. & S. Soosairaj, sp. nov. 8. Bract and calyx lobes single nerved, bract margin hyaline....................................................... L. hyalina Nees — Bract and calyx lobes 3-7 nerved, bract scarious or coriaceous..................................................................... 9 9. Bract scarious, lower calyx lobes 3-ribbed, upper 7-ribbed...................................................... L. scariosa Nees — Bract coriaceous, calyx lobes 3-ribbed........................................................................................................ 10 10. Flowers in soft, condensed spike, leaves crenate-serrate........................................... L. fasciculata (Retz.) Nees — Flowers in elongate spike, villous, leaves entire or undulate................................................. L. cuspidata Nees, Published as part of Dhatchanamoorthy, Narayanasamy, Karthikeyan, Chinnasamy, Raja, Prakasam, Soosairaj, Sebastian & Balachandran, Natesan, 2022, Lepidagathis decumbens N. Dhatchan. & S. Soosairaj, sp. nov. (Acanthaceae), a new species from Tamil Nadu, India, pp. 321-329 in Adansonia (3) (3) 44 (24) on page 328, DOI: 10.5252/adansonia2022v44a24, http://zenodo.org/record/7254723

Dhatchanamoorthy, Narayanasamy, Karthikeyan, Chinnasamy, Raja, Prakasam, Soosairaj, Sebastian, Balachandran, Natesan (2022): Lepidagathis decumbens N. Dhatchan. & S. Soosairaj, sp. nov. (Acanthaceae), a new species from Tamil Nadu, India. Adansonia (3) 44 (24): 321-329, DOI: 10.5252/adansonia2022v44a24

Solanum pulneyensis Soosairaj, sp. nov. (Figs 1; 2) TYPUS. ��� India. Tamil Nadu, Dindigul district, Palani Hills National Park, Thonimalai, (10��22���37.95���N, 77��46���41.99���E), c. 1300 m, 29. I.2018. S. Soosairaj 2514 (holo-, RHT!; iso-, MH!). DIAGNOSIS. ��� This species differs from other Solanum species by subcapsular fruits that are entirely enclosed by calyx. It has supra axillary cyme inflorescence with 2-3 flowers. This species also has distinctive features such as obtuse leaf apex, unarmed petiole and pedicel, simple stigma and glabrous anther. HABITAT AND PHENOLOGY. ��� Solanum pulneyensis Soosairaj, sp. nov. was found growing in savanna forest in the Western Ghats of Palani Hills National Park, on a slope at 1300 m elevation amidst tall grasses like Cymbopogon citratus (DC.) Stapf. The vegetation type has been described as sub-tropical hill savanna (8A/DS1) which is interrupted with patches of southern hill top wet evergreen forests (Champion & Seth 1968). The new species was found associated with Breynia retusa (Dennst.) Alston, Peperomia blanda (Jacq.) Kunth, Kalanchoe bhidei Cooke, Hedyotis swertioides Hook. f., Pogostemon mollis Benth., Desmodium parvifolium DC., Kleinia grandiflora (DC.) N. Rani, Smithia hirsuta Dalzell, Arundinella ciliata (Roxb.) Nees ex Miq., Eragrostis deccanensis Bor. and Polygala rosmarinifolia Wight & Arn. The species is found growing in steep slope and soil is shallow with exposed rocks. Flowering occurs in January-March, and fruiting from February and March. DISTRIBUTION. ��� Solanum pulneyensis Soosairaj, sp. nov. is known only from the Thonimalai, Palani Hills National Park, Dindigul district from Tamil Nadu, India. ETYMOLOGY. ��� The specific epithet is chosen to represent the Palani hills, the collection locality which is a part of Western Ghats of India. CONSERVATION STATUS. ��� The population of this species was noted at two locations at a close proximity observed to be populated with about 15-20 individuals. Based on the field observations made periodically, the conservation status of the species has been evaluated following the latest IUCN Red List Criteria (Version 3.1; IUCN 2012). The species qualifies for Critically Endangered under criteria B2, C2 and D. Criterion B1 cannot be estimated as the EOO required to predict is at least 2 locations (Fig. 3). Criterion B2: This species is found only at the Thonimalai (subcriterion a). The AOO measured at 2 km 2 grid size for Solanum pulneyensis Soosairaj, sp. nov. is 4 km 2. A continuing decline of population is inferred (subcriterion b) in terms of quality of habitats such as the construction of estate and tea plantations. As this estimate is less than 10 km 2, the species qualifies for Critically Endangered category. Criterion C2: A continuing decline of population is inferred in terms of quality of habitats as the establishment of estate and tea plantations push this species to extreme. The number of mature individuals in the population noted was about 15-20 individuals. Criterion D: Only ten to fifteen individuals in total were documented during the study period which is much lower than the threshold level of fifty mature individuals and makes the species qualify for Critically Endangered category criterion. Though this species could be considered as Data Deficient (DD) due to its distribution, we could anticipate that the uncertainty on the conservation of the habitats which are favorable for the growth of Solanum pulneyensis Soosairaj, sp. nov. shall be assessed as Critically Endangered criteria CR[B2ab(iii); C2a(i); D]. DESCRIPTION Armed, undershrub, 50-70 cm tall, stellate tomentose throughout. Stem stellate tomentose, prickled, prickles straight, 1-1.5 mm, yellow. Leaves simple, alternate, oblong-ovate, 3-6.5 �� 2-4 cm, base truncate, oblique, margin undulate, stellate tomentose on both the surfaces, apex obtuse, midrib with 1 or 2 prickles below, lateral nerves 3-4 pairs, without prickles; petiole 8-23 mm, prickled. Inflorescence a cyme, supra axillary, 2-3 flowered, peduncle 5-6 mm long. Flowers 20-23 mm across, pedicel up to 18 mm, not prickled; Calyx cupular, rotate, 9-10 mm, densely stellate tomentose without, glabrous within, lobes 5, lanceolate with prominent midnerves, 5-6 mm, apex acuminate; Corolla rotate, 5 lobed, pale purple, lobes orbicular, 4-5 mm, undulate, stellate tomentose without, glabrous inside, midnerve yellowish from the base; Stamens 5, filaments 1-2 mm, glabrous, anthers unequal, 3 long, 7-8 mm, falcate, 2 short, 5-6 mm, lanceolate, glabrous, yellow, poricidal. Pistil 12 mm; ovary ovoid, 1-1.5 mm, style 11-12 mm long, capillary, glabrous, curved; stigma simple. Fruit subcapsular, globose, 8-10 mm across, pale green with white patches, fruiting calyx accrescent, 13-14 mm, lobes 10-11 mm, stellately tomentose, not prickled. Seed rhomboid, 3.5�� 3 mm, pale brown, alveolate, margin bulged. AFFINITIES Solanum pulneyensis Soosairaj, sp. nov. is a distinct species since it has a subcapsular fruit. It resembles with S. wightii Nees in having accrescent fruit calyx that covers the fruit completely but differs in having subcapsular fruit, obtuse leaf apex, glabrous anther, calyx and petiole without prickles (Table 1). It is also similar to S. cordatum in having similar features like oblong-ovate leaves, 2-3 flowered cymes but differs in having subcapsular fruit that dehisces irregularly at apex and fruit that is pale green with white patches. Although most of the Solanum species have berry as common fruit type, Symon (1979, 1981) reports subcapsular fruit in Solanum rostratum Dunal, a widespread weed in his revision of Australian Solanum species., Published as part of Soosairaj, Sebastian, Raja, Prakasam, Balaguru, Balakrishnan & Tagore, Johny Kumar, 2021, Solanum pulneyensis Soosairaj, sp. nov. (Solanaceae) from Palani Hills National Park of Tamil Nadu, India, pp. 235-240 in Adansonia (3) (3) 43 (21) on pages 236-238, DOI: 10.5252/adansonia2021v43a21, http://zenodo.org/record/5706047, {"references":["CHAMPION H. G. & SETH S. K. 1968. - Revised Survey of the Forest Types of India. Manager of Publications, New Delhi: 255, 256.","IUCN 2012. - Iucn Red List Categories and Criteria. Version 3.1. 2 nd edition. Gland, Switzerland and Cambridge.","SYMON D. E. 1979. - Fruit diversity and dispersal in Solanum in Australia. Journal of the Adelaide Botanic Gardens 1: 321 - 331.","SYMON D. E. 1981. - A revision of the genus Solanum in Australia. Journal of the Adelaide Botanic Gardens 4: 1 - 367."]}

Tropical dry forests occur as patches in Tamil Nadu distributed along the East Coast, Eastern Ghats, and plains of the Indian Peninsula. The floristic studies of these regions are of great national relevance as plant resources in a tropical climate contribute to national wealth. Dry forests of the plains in Tamil Nadu have been neglected and the area under study has remained practically unexplored. This chapter studies distribution of tropical dry forests, especially in Pudukkottai district in Tamil Nadu. In total, 187 sacred groves were surveyed for their distribution and floristic composition. The GPS position of each grove was noted and their distribution maps were prepared. The groves were classified based on conservation status, namely well conserved, moderately conserved and degraded. Extensive botanical explorations were carried out periodically during 2012–2016 in these groves and 812 species belonging to 480 genera under 124 families were recorded. The endemic, threatened species of these groves were also documented.