Crotalaria shrirangiana K. H. Rokade, Dalavi, Swaroopsingh Gaikwad et N. B. Gaikwad, 2020

Rokade, Krishnat, Dalavi, Jagdish Vishnu, Gaikwad, Swaroopsingh & Gaikwad, Nikhil, 2020, Crotalaria shrirangiana (Fabaceae): A new rattlepod from the Western Ghats of India, Phytotaxa 449 (2), pp. 188-194 : 191-192

Crotalaria shrirangiana K. H. Rokade, Dalavi, Swaroopsingh Gaikwad et N. B. Gaikwad , sp. nov. ( Figs. 1 & 2 )

Type:— INDIA. Maharashtra: Satara district, Pasarni Ghat, Near Wai 713 m, 16 o 35.519’ N, 073 o 22.997’ E, 25 December 2019, K.H. Rokade, Dalavi, S.V. Gaikwad & N.B. Gaikwad, KR–50 (holotype CAL!, isotypes BSI!, CAL!, SUK!).

Diagnosis: — Crotalaria shrirangiana is morphologically similar to Crotalaria juncea but it differs from the latter in having slender stems (furrowed in C. juncea ); lanceolate-mucronate leaves (oblanceolate and non-mucronate leaves in C. juncea ); inflorescence a raceme with 6–8 flowers, 10–15 cm long, (inflorescence up to 30 cm with 15–20 flowers in C. juncea ); bracts linear-lanceolate (ovate-lanceolate in C. juncea ); standard petal broader than longer, emarginate at apex (longer than broader, acute to obtuse at apex in C. juncea ); seeds 6–8 per pod, 5 × 3.5 mm, yellowish brown (12–14 seeds per pod, 3.5 × 3 mm, blackish brown in C. juncea ). Morphological differences between C. shrirangiana and C. juncea are summarised in Table 1.

Description: —An erect profusely branched undershrub, up to 1.5 m. Stem 2–5 mm thick, terete and densely clothed with hairs. Leaves simple, alternate, petioles 1–1.5 mm long, exstipulate; lamina 3–4 × 0.5–0.8 cm, linear lanceolate, acute at the base, obtuse and slightly mucronate at apex; margin entire, densely hairy beneath and glabrescent above. Inflorescence lax raceme, terminal, peduncles 10–15 cm long, slender, filiform, clothed with appressed hairs. Flowers 6–8, 1.4–1.8 × 1.6–2 cm across, distinctly pedicellate; pedicels 3–4 mm long; bracts linear 3–4 × 0.8–1 mm long; bracteoles 2, 4–4.5× 0.5 mm, appressed to calyx, strigose hairy; calyx tube 5 mm long, sepals 5, 10 × 3 mm, lobes linear lanceolate, anterior two sepals forming deep notch, densely brown strigose hairy, three others are lanceolate, connate at base, acute at apex, strigose hairy throughout; corolla bright yellow, petals 5, standard petal 1.4–1.6 × 1.6–2 cm, with fine purple striations arising from the base, apex emarginated, notched, finely pubescent on back; wing petals 0.8–1 × 0.5 cm; keel petals 0.8–1 × 0.5 cm, rostrate, fused and slightly twisted at the end; staminal sheath 6 mm long, stamens 10, monadelphous, dimorphic, basifixed, free longer filaments 4–6 mm long, anthers with longer filament ovoid, 1 mm long while anthers having shorter filament are arrow headed, 2.5 mm long. Gynoecium 12 mm long, ovary sessile, elongated, densely hairy 5 × 2 mm, ovules 6–8, style 7 mm long, sparsely hairy, hairs in two parallel rows. Pods sessile, 2–2.1 × 0.6–0.7 cm, oblong, densely clothed with brown hairs, beak inconspicuous, slightly curved. Seeds 6–8, oblique-cordiform, yellowish brown, polished.

Etymology: —The specific epithet ‘ shrirangiana’ honors Prof. (Dr.) Shrirang Yadav, INSA Senior Scientist, Department of Botany, Shivaji University, Kolhapur, M.S. ( India) for his significant contribution in Botany and Plant Taxonomy.

Phenology: —Flowering November to January; fruiting December to February.

Distribution: — Crotalaria shrirangiana was collected from Pasarni Ghats, near Wai in Satara district of Maharashtra, India. It is found in hilly regions along forest margins.

Conservation status: —As data is insufficient on distribution and population of Crotalaria shrirangiana , it is assessed as Data Deficient (DD) following the IUCN Categories and Criteria ( IUCN 2012).

Habitat: —The type locality of the new species is situated amidst the ranges of Western Sahyadri hills at approximately 40 kms. north of the city of Satara. It has an average elevation of 745 metres. The annual rainfall is 5760 mm and average annual temperature is 25°C. Crotalaria shrirangiana grows in association with Alysicarpus pubescens Law (1839: 250) , Crotalaria prostrata var. prostrata Rottler ex Willdenow (1809: 747) , C. filipes var. filipes Bentham (1843: 475) , C. juncea Linnaeus (1753: 714) , C. mysorensis Roth (1821: 338) , C. orixensis Willdenow (1803: 217) , C. hebecarpa Rudd (1983: 28) , C. notonii Wight & Arnott (1834: 192) , C. vestita Baker (1876: 67) , Indigofera linifolia (L.f.) Retzius (1786: 29), Rungia elegans Dalzell (1861: 196) , Rhynchosia rothii Bentham ex Aitchson (1869: 50) and Stylosanthes fruticosa (Retzius) Alston (1931: 77) .

Note:— Crotalaria shrirangiana is commonly found along roadsides in Ghats and in open grasslands. Due to similarity in morphological characters and intermingled populations of this species with Crotalaria juncea the species might have been missed by previous taxonomist.

Figures

FIGURE 1. Plate showing diagnostic differences between Crotalaria shrirangiana sp. nov and C. juncea. Crotalaria shrirangiana sp. nov. A. Habit; B. Leaf; D. Flower; F. Bract and bracteoles; H. Calyx; J. Dissected corolla; K. Standard petal; M. Pod; O. Androecium; P. Gynoecium; Q. Seeds. Crotalaria juncea. C. Leaf; E. Flower; G. Bracts and bracteoles; I. Calyx; L. Standard petal; N. Pod; R. Seeds. Photographs from Rokade, Dalavi, Gaikwad & Gaikwad (KR-50) for Crotalaria shrirangiana and Dalavi & Krishnat Rokade (KR-52) for C. juncea by Krishnat Rokade & Jagdish Dalavi

FIGURE 2. Crotalaria shrirangiana sp. nov. A. Habit; B. Leaf; C. Flower; D. Bract and bracteoles; E. Calyx; F. Dissected corolla; G. Androecium; I. Pod; J. Open pod; K. Seed. Illustrated from Rokade, Dalavi, Gaikwad & Gaikwad (KR-50) by Krishnat Rokade & Jagdish Dalavi.