3. Schistura sharavathiensis sp. nov.

Holotype: 26.iii.2004, Sharavathi river (l4°8'15"N-74°44'30"E), Kalkatte tributary, 1 km upper to Dabbe falls, Shimoga, Kamataka, 29.0mm SL, coll. Sreekantha and Vishnu D. F-7597 ZSI/SRS.

Paratypes: 26.iii.2004, 3 exs., 26.0mm SL and 24.0mm SL, ZSI/SRS F-7598, 28.vii.2004; 26.0mm SL, IISc/CES/WGBlS: 3-5-3-5­008, locality and collectors as in Holotype.

3.2 Etymology

Named after its type locality, Sharavathi river, Central Western Ghats.

3.3 Diagnosis

A species of Schistura depicted in Image 3, distinguishable from other members by the following combination of characters: processus dentiformis well developed; 16-18 almost regular brown bars on body, narrower than interspaces; males without suborbital flap; nasal tube with a prolonged barbel, long with unculi; lateral line with 5-6 pores, reaching one third of pectoral fin; lower lip with a median interruption, each side with 4-5 deep furrows; 81/2 dorsal, 9 pectoral, 7 pelvic and 7-8+8 caudal rays, slightly emarginate caudal fin; black basal caudal bar with a darker central spot; caudal fin plain; no axillary pelvic lobe; pelvic origin below dorsal or slightly behind; anus much nearer to anal fin; a long and high adipose crest from just behind dorsal fin, a shorter ventral crest.

Image 3: Schistura sharavathiensis sp. nov(SL 32.0mm) paratype from type locality,(IISc/CES/WGBIS : 3-5-3-5-008)

Morphological and proportionate values of Schistura sharavathiensis are listed in Tables 1 and 2 respectively. Body moderately elongate, depth increasing to dorsal fin and thereafter tapering posteriorly; mouth semi-circular; both lips fleshy, median incision in upper lip and lower lip interrupted in the middle with 4-5 deep furrows on each side (Image 4); processus dentiformis well-developed; nasal tube with a prolonged barbel; head length slightly greater than depth; barbels well-developed, long with unculi; nasal barbel prolonged as in members of the genus Oreonectes of the same family; lateral line incomplete, ending at mid level of mid region of pectoral fin, with 5-6 pores, cephalic lateral line system with 6 supraorbital, 4+8 infraorbital, 9 preoperculomandibular and 3 supratemporal pores; fin ray counts include, dorsal 8'/2, pectoral 9, pelvic 1/7, anal 2/5 and caudal 7-8+8; dorsal fin equidistant from tip of snout to caudal fin base; dorsal fin with convex distal margin; pelvic fin does not reach vent and separated by a wide distance; no axillary pelvic lobe; anal fin not reaching caudal fin base; pectoral fin reaches half the distance to pelvic origin; pelvic fin reaches half the distance to anal fin without reaching anus; caudal fin slightly emarginate with rounded lobes and upper lobe longer than lower; long ventral and dorsal adipose crest present.

Image 4: Schistura sharavathiensis - Ventral view of head

3.5 Colour

Body light yellowish-brown with 16-18 almost regular thin cross bars, narrower than interspaces, dark brown in live specimens and dull white in preserved specimens, the bars reach ventral surface behind dorsal fin; dorsal fin with a row of spots at three quarters height; caudal fin plain with dissociated band at base with a central spot; other fins without any prominent colour pattern.

3.6 Habitat

3.7 Distribution

Sharavathi river basin, Central Western Ghats, Karnataka, India.

3.8 Discussion

Schistura sharavathiensis resembles the species of the genus Longischistura Banarescu and Nalbant, only in the presence of a long adipose crest extending from a short distance behind dorsal fin to caudal base; but differs with respect to 10 dorsal rays, deeply forked caudal fin, complete to almost complete lateral line in Longischistura genus. It also resembles genus lndoreonectes in long nasal barbel (Oreonectes genus, Kottelat, 1990) and adipose crest on the caudal peduncle. However, it differs from I. keralensis and I. evezardi in the presence of rounded and banded caudal fin, broad and incomplete, irregular vertical bands or mottled all over the body. The identity of the species is confirmed based on the available literatures of Schistura in South-Asian region (Menon, 1987; Kottelat, 1990; Talwar and Jhingran, 1991; Jayaram, 1999; Kottelat, 2004; Vishwanath and Nebeshwar, 2004; Vishwanath and Shanta, 2004; Vishwanath and Sharma, 2005). Table 3 shows the comparison between the six recorded taxa of Western Ghats, which reveals that S. sharavathiensis differs significantly from the congeners, except for S. nilgiriensis . It differs in the presence of 5-14 vertical bands and a black spot at anterior base of dorsal fin in S. nilgiriensis . Appendix-1 gives the identification keys for species. Plot of principal components (of PCA) shows different clusters indicating variations between S. sharavathiensis and S. nilgiriensis (Fig. 3) with eigen values of 159.29 for PC 1 (accounts for 96.48% variability) and 5.42 for PC 2

Figure 3. Plot of principal components of 31 morphological parameters - Schistura sharavathiensis and S. nilgiriensis .

3.9 Comparative Material

Schistura kodaguensis : 06.x.2004, Kootu Hole (12°26'59"N­75°42°46"E), about 8 km northwest of Mercar a, Coorg, Karnataka, 2 exs. 23.0mm SL and 29.0mm SL, coll. Sreekantha, Vishnu D. and Gururaja K.V., IISc/CES/WGBIS: 3-5-3-5-005.

Schistura nilgiriensis : 06.xi.2003, Sharavathi river, Niluvase (13°44'18"N-75°06'30"E), Shimoga, Karnataka, 2 exs. 39.0mm SL. and 43.0mm SL, coli. Sameer Ali, Gururaja KV and Vishnu D, IISc/CES/WGBIS: 3-5-3-5-004.

Schistura denisoni denisoni : 21.xi.2003, Sharavathi river (13°52'44"N-75°03'64"E), Jayanagar, Shimoga, Karnataka, 2 exs. 31.0mm SL and 39.0mm SL, coil. Sreekanthaand Vishnu D, IISc/ CES/WGBlS: 3-5-3-5-001.

Schistura semiarmatus : 23.xi.2003, Sharavathi river (75°03'52"N­13°52'45"E) Suttha, Shimoga, Karnataka, 2 exs. 32.0mm SL and 34.0mm SL. Coil. Sreekantha and Vishnu D, IISc/CES/WGBlS: 3-5-3-5-006.

Table 1. Nophometric characteristics of Schistura nagodiensis sp. nov. and Schistura sharavathiensis sp. nov. (dimensions in mm)

Table 2. Proportional values of morphometry of Schistura nagodiensis sp. nov. and Schistura sharavathiensis sp. nov.

Table 3. Comparison of morphological characters of Schistura of Western Ghats.