Nemacheilus kaimurensis

Husain & Tilak, 1998

Class: Actinopterygii (Ray-finned fishes)
Order
: Cypriniformes (Carps)
Family:
Balitoridae (River loaches)
Genus
: Nemacheilus

Environment:  Demersal; freshwater
Climate:
  Subtropical

Distribution:  Asia: India.

Description: B. iii, D. III/8, P. I/9-10, V. I/5-6, A. III/5, C. 17(9/8). Morphometric characters (in per cent). Head length 22.68-25.00; body depth 15.60-16.67; body width 12.12-14.29; pre-dorsal distance 47.17-50-76; post-dorsal distance 48.31-50.00; pectoral fin 21.23-24.39; pectoral to pelvic fin distance 27.25-28.57; pelvic fin 16.18-17.86; pre-pelvic distance 48.95-50.00; pelvic to anal fin distance 22.83-25.00 height at anal fin origin 11.76-13.33; anal fin 14.00-16.18; pre-anal distance 68.49-75.19; post-anal distance 24.10-26.46; caudal length 13.25-17.18; 24.10-26.46; caudal peduncle length 13.25-17.18; caudal fin 25.00-30.00 per cent of standard length.

Head width 42.92-64.94; head height 50.00-59-88; snout length 38.61-45.45; eye diameter 21.28-23.98; post-orbital head length 42.92-46.30; gape of mouth 21.28-28.57; inner rostral barbel 21.41-36.36; outer rostral barbel 38.46-45.45; maxillo-mandibular barbel 25.00-33.33; body depth 64.52-71.43; body width 50.00-59.88: dorsal fin height 78.13-86.96; dorsal base 57.14-68.97; pectoral fin 87.72-104.17; distance between outer edges of base of pectorals 56.18-59.88; pelvic fin 68.97-76.34; distance between outer edges of base of pelvics 31.25-37.45; height at anal origin 52.08-56.18; anal fin 62.50-68.97; caudal peduncle length 56.18-73.53; caudal fin 106.38-121.95 per cent of head length.

Eye diameter 70.92-100.00 of interorbital width and 48.54-59.88 per cent of snout length; interorbital width 40.00-56.82 per cent; gape of mouth 40.00-56.82; distance between outer edges of base of pectorals 90.09-133.33 and distance between outer edges of base of pelvics 50.00-73.53 per cent of head width; inner rostral barbel 51.55-66.67; outer rostral barbel 85.47-100.00 and maxillo-mandibular barbel 57.14-83.33 per cent of snout length; dorsal fin height 108.70-129.87 per cent of body depth; pectoral fin 75.19-86.96 per cent of pectoral to pelvic distance; pelvic fin 64.94-78.13 and anal opening to anal fin distance 20.00-26.88 per cent of pelvic to anal fin distance; anal base 53.19-63.69 per cent of dorsal base; least height of caudal peduncle 54.64-78.13 per cent of its length and 66.67-82.64 per cent of height at anal fin origin.

Small sized loach. Head with sensory canals. Barbels three pairs with fine nodular out growths; inner rostrals smallest, not reaching nasal opening; outer rostrals longest, reaching anterior one-third of eye; maxillo-mandibulars medium sized. Membranous flap between anterior and posterior nostrils blunt-tipped. Eyes dorso-lateral, slightly in anterior half of head, not visible from ventral side. Dorsal fin origin slightly ahead of pelvics, variable in relation to distance between it and snout tip and caudal base. Pectorals obtusely rounded (none of its ray produced or prolonged), not reaching pelvics. Pelvics with an axillary fleshly appendage, may or may not reach anal opening. Anal origin opposite tip of last dorsal ray or slightly behind that, not reaching caudal base. Caudal fin emarginate, lobes bluntly pointed, lower lobe slightly longer than upper lobe. Margin of all the fins wavy as the membrane between the rays deeply notched, a characteristic feature of the species. Lateral line complete, raised. Scales minute, irregularly arranged on lateral sides of body and almost missing from dorsal side and abdomen. Head and upper surface of pectoral and pelvic fins finely grainulated irrespective of the sex.

Colouration: Body pale with 5-6 small, variously shaped brownish spots along lateral line, 6-8 saddleshaped dark spots on dorsal side of body (3 before, 1-2 under and 2-3 behind dorsal fin) and a darker rounded spot at caudal base, some examples with another smaller spot on upper edge of caudal base. Snout with two faint short parallel lines; a short transverse band between nostrils of each sides and another between the eyes and the third one on occiput; two narrow and oblique spots, one each on dorso-lateral side of head present above operculum; very minute scattered dots around eye and on operculum. Barbles pale. Lyes dark. Fins translucent; dorsal and caudal fins finely dotted in middle and that of caudal fin all along but more so on upper lobe.

Sexual dimorphism: The species exhibits sexual dimorphism by the presence of a movable club-shaped appendage below the anterior margin of eye in the males. The females lack this character.

Habitat: The material was collected from Kanhar stream near village Kota, Chopan. This is a slow moving stream, with yellowish sandy and gravelly bed and is a tributary of river Sone (a major tributary of Ganga). At the time of collection the stream was flowing in channels with a thin film of clean water. The wegetation was near the banks and there were a few scattered boulders in the bed. The area falls within Kaimur range composed of low hills and almost at the plain level.

Material examined: India: Collections were made by dragging the hand net (with ring and rod arrangement) along the bed. Type Material: Holotype: ♂, 42 mm in total length. Locality: Kanhar stream, near village Kota, Chopan, Dist. Sonbhadra, Uttar Pradesh. Date: 20. iv. 1986. Coll. Raj Tilak and Akhlaq Husain. Regd. No. NRS/ZSI/F. 1543. Paratype : ♂ ♀, 33 examples, 36-43 mm in total length. Locality and other data same as of Holotype. Regd. No. NRS/ZSI/F. 1544.

Remarks: Nemacheilus kaimurensis is closely allied to N. corica (Hamilton-Buchanan) but differs from it in the absence of prolonged third outer pectoral fin ray, wavy fin margins, colouration and other features. Tilak (1971) pointed out that third outer pectoral fin ray of N. corica is the longest, reaching the middle of the pelvic base. Menon (1987) also noted this character. Further, N. corica is distributed all along the base of Himalaya (Menon. 1974, 1987) whereas N. kaimurensis, is found in Kaimur range (Central India) composed of low hills and almost at the plain level.

Material examined: India: Collections were made by dragging the hand net (with ring and rod arrangement) along the bed. Type Material: Holotype: ♂, 42 mm in total length. Locality: Kanhar stream, near village Kota, Chopan, Dist. Sonbhadra, Uttar Pradesh. Date: 20. iv. 1986. Coll. Raj Tilak and Akhlaq Husain. Regd. No. NRS/ZSI/F. 1543. Paratype : ♂ ♀, 33 examples, 36-43 mm in total length. Locality and other data same as of Holotype. Regd. No. NRS/ZSI/F. 1544.

Comparison of characters of Nemacheilus kaimurensis and N. corica (Hamilton-Buchanan)

Nemacheilus kaimurensis

Character
1. Inner rostral barbel – Not reaching front edge of eye or even nasal opening.
2. Outer rostral barbel – Reaching anterior one-third of eye.
3. Internarial membranous flap – Bluntly pointed, not produced  into a tendril or barbel.
4. Pectoral fins – Simple, obtusely rounded, generally shorter than head, first branched ray not thickened in males.
5. Pelvic fin rays – I/5-6 .
6. Caudal fin – Emarginate or slightly forked.
7. Margin of fins – Wavy.
8. Head per cent of standard length – 22.68-25.00 .
9. lnterorbital width per cent of head width – 40.00-56.82.
10. Postorbital length of head  per cent of head length – 42.92-46.30.
11. Dorsal base per cent of head length – 57.14-68.97.
12. Postdorsal distance per cent of standard lenght – 48.31-50.00.
13. Pelvic fin per cent of  head length – 68.97-76.34.
14. Post pelvic distance per cent of total length and standard length respectively – 38.17-40.00; 46.95-50.00.
15. Anal fin per cent of head length – 62.50-68.97.
16. Anal base per cent of  dorsal base – 53 .19-63.69.
17. Scales – Irregularly arranged on lateral sides o body missing from dorsal and ventral sides.
18. Lateral line – Prominent, being raised above the skin.
19. Coloruation – 5-6 spots along lateral line and 2 short streaks on snout one each between snout tip and nostril.
20. Maximum size (examined) – 43.00 mm.
21. General distribution – Kaimur range, Sonbhadra District, Uttar Pradesh, India.

 

       Nemacheilus corica

Character
1. Inner rostral barbel – Reaching front edge of eye.
2. Outer rostral barbel – Reaching middle of eye, slightly beyond or hind edge of eye.
3. Internarial membranous flap – Ends an a fine tendril simulating a barbel.
4. Pectoral fins – Third ray produced, fin longer than head, first branched ray thickened in males.
5. Pelvic fin rays – I/7.
6. Caudal fin – Deeply forked.
7. Margin of fins – Simple.
8. Head per cent of standard length – 16.67-2 1 .23.
9. lnterorbital width per cent of head width – 29.41-30.86.
10. Postorbital length of head  per cent of head length – 38.76-41.32.
11. Dorsal base per cent of head length – 77.52-88.50.
12. Postdorsal distance per cent of standard lenght – 52.91-55.25.
13. Pelvic fin per cent of  head length – 80.00-84.75.
14. Post pelvic distance per cent of total length and standard length respectively – 42.02-43.48;
52.08-53.76.
15. Anal fin per cent of head length – 70.42-77.52.
16. Anal base per cent of dorsal base – 70.42-77.52.
17. Scales – Embricately arranged, more prominent posteriorly.
18. Lateral line – Simple.
19. Coloruation – 11-13 spots along lateral line and streaks absent.
20. Maximum size (examined) – 74.00 mm.
21. General distribution – Along base of Himalaya in India, Pakistan, Nepal, and Bangladesh.

Links:

http://www.fishwise.co.za/Default.aspx?TabID=110&GenusSpecies=Nemacheilus_kaimurensis&SpecieConfigId=280154

 

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