Brevibora cheeya, Liao & Tan, 2011

Liao, Te-Yu & Tan, Heok Hui, 2011, Brevibora Cheeya, A New Species Of Cyprinid Fish From Malay Peninsula And Sumatra, Raffles Bulletin of Zoology 59 (1), pp. 77-82 : 78-81

publication ID	https://doi.org/ 10.5281/zenodo.10106859
persistent identifier	https://treatment.plazi.org/id/039D87E7-FF87-FF98-FEFE-0929FE89FDFA
treatment provided by	Tatiana
scientific name	Brevibora cheeya
status	sp. nov.

Treatment

Brevibora cheeya View in CoL , new species

( Figs. 3 View Fig , 4 View Fig )

Material examined. –. Holotype – ZRC 51965, 26.6 mm SL; Malaysia: Terengganu, Rantau Abang, 56 km to Kuala Terengganu; P.K.L. Ng et al, 16 May.1995.

Paratypes - ZRC 40196, 10 View Materials , 20.4-27.3 mm SL; same data as holotype. - CMK 8156, 20, 12.9-22.8 mm SL, ZRC 24127, 17 View Materials , 13.3-22.3 mm SL; same locality as holotype; M. Kottelat et al., 18 Mar.1992 . - ZRC 51966, 46 View Materials , BMNH 2010.1.11.1-70, 70, 14.1-25.5 mm SL; Malaysia: Terengganu, Rantau Abang , 56 km to Kuala Terengganu; L. Rüber et al., 28 Feb.2009 .

Additional non-type material. – ZRC 39158, 11 View Materials (1 C&S), 11.4-28.0 mm SL; Indonesia: Sumatra: Jambi: Berbak Nature Reserve , Sungai Air Hitam Dalam; H.H. Ng & S.H. Tan, 16-17 Jun.1995 . - ZRC 43116, 1 View Materials , 19.6 mm SL; Indonesia: Sumatra: Riau: Indragiri , Sungai Jakil; H.H.Tan et al., 25 Nov.1996 . - ZRC 30911, 2 ex., 30.4-30.9 mm SL; Sumatra: Banka island , Kampung Jelit; M. Kottelat et al., 2 Mar.1993 . - ZRC 3206 View Materials , 406 View Materials , 10.9-38.8 mm SL; Malaysia: Pahang, Tasek Bera; C.C. Lindsey, 29 Mar.1963 . - ZRC 18826, 7 View Materials , 25.9-31.9 mm SL; Malaysia: Selangor, Tanjung Malim ; P.K.L. Ng et al., 14 Sep.1991 . - ZRC 42852, 4 View Materials , 20.0- 21.5 mm SL; Malaysia: Johor, Sungei Kayu ; H.H. Tan et al., 12 Mar.1998 .

Diagnosis. – Brevibora cheeya is distinguished from B. dorsiocellata by the complete lateral line (25-30 perforated scales vs. 4-9), more scales along the lateral row (29-32 vs. 25-27), larger size (up to 39.0 mm SL vs. 23.0 mm SL); and larger head and prepectoral length (head length 28.5- 30.0% SL, vs. 24.4-27.9; prepectoral length 29.6-32.9% SL, vs. 25.8-28.8).

Description. – Refer to Fig. 3 View Fig for overall body shape and to Table 1 for morphometric data. Body laterally compressed, rather elongated. Head short. Snout pointed. Mouth terminal, reaching vertical of anterior orbit. Dorsal-fin origin at highest point of body outline. Predorsal contour almost straight, with a slight depression on snout. Ventral outline slightly curved from tip of snout to the middle of caudal peduncle. Barbel, keel and tubercles absent.

Dorsal-fin origin opposite or slightly ahead to pelvic-fin origin, tip of last branched ray opposite to anal-fin origin, pointed, posterior outline rather straight. D. ii.6 (11). Longest pectoral-fin ray (1 st or 2 nd branched ray) almost reaching pelvic-fin origin. P. ii.11 (2), ii.12 (8). Pelvic fin triangular, longest ray almost reaching anal-fin origin. V. ii.8 (10). Anal-fin origin closely behind vent, posterior outline concave, longest ray not reaching caudal fin A. iii.5 (11). Caudal fin deeply forked.

Lateral line complete with 25-30 perforated scales [25 (1), 26 (2), 27 (5), 28 (1), 29 (1), 30 (1)], last two to six scales not perforated. Lateral row with 29-32 scales [29 (3), 30 (3), 31 (3), 32 (2)], including two scales on base of caudal fin, lateral row descending from 1 st to 4 th scale and rather horizontal between 5 th and 7 th, then descending from 8 th scale onwards to caudal-fin base (scale number based on holotype). Predorsal scales 10-11 [10 (9), 11 (2)]. Transverse line scales ½ 4/1/3 ½ (11). One scale between lateral-line scale row and the pelvic-fin origin. Circumpeduncular scales ½ 3/1/1 ½ (11). Pectoral axillary scale rudimentary. Pelvic axillary scale well developed, corresponding to 1/3 of pelvic fin in length.

Predorsal vertebrae 8-9 [8 (10), 9 (1)], abdominal vertebrae 16 (11), caudal vertebrae 15-16 [15 (10), 16 (1)], total vertebrae 31-32 [31 (10), 32 (1)]; pharyngeal teeth in three rows, 5, 4, 2; 2, 4, 5 (1), rasborin process present.

Coloration in preservative. – Dorsum dark brownish, ventral gradually lighter. Abdomen yellowish. Dorsum of head dark brownish. Tip of snout more densely pigmented than adjacent area, exhibiting an appearance of dusky lips. Suborbital yellowish. Gill cover rather transparent with brownish pigment. Iris whitish, black dorsally and ventrally. Dorsal stripe prominent, half of dorsal-scale row in width. Reticulate pattern on sides distinct. Melanophores densely scattered along distal margin of scales in three or four rows, more prominent in dorsal half of body. An axial streak running from two scales in front of caudal-fin base to the upper edge of gill opening, fading out anteriorly. Dark lateral stripe absent. Supra-anal pigment present as a streak and connected with subpeduncle streak, both blackish. A distinct black blotch on anterior middle dorsal fin, intensely pigmented with a defined outline, oval in shape, covering two unbranched and first four branched rays. Other fins hyaline, with some melanophores scattered on fin rays. Melanophores most intense on distal half of anal fin rays, similar to a blotch in overall shape. Inter-radial membrane of anal fin transparent. It is not sure whether the blotch on anal fin due to stronger pigmentation caused by environmental factors. In the smallest specimen of ZRC 39158 ( Fig. 4 View Fig ) the distal half of its pelvic fin rays with highly scattered melanophores and pigmentation on its anal fin rays more intense than larger specimens. It is postulated that this pigmentation fades out upon maturity.

Distribution and field notes. – Brevibora cheeya is distributed both in the westerly and easterly flowing river basins of Peninsular Malaysia (western: Selangor; eastern: Terengganu, Pahang, Johor), Central Sumatra (Jambi, Riau) and Banka Island ( Fig. 5 View Fig ). Brevibora dorsiocellata appears to be restricted to the Muar river basin in Malaysia, but this could be due to insufficient sampling (based on ZRC material and second author pers. obs.); but occurs in Central Sumatra, where B. cheeya is also present, but seemingly in different sub-basins. The Brevibora dorsiocellata group is also present in Borneo, and will be covered in more detail in future works.

The type locality in Malaysia is in a coastal heath forest ( Fig. 6 View Fig ). This habitat consists mainly of Melaleuca (Myrtaceae) stands on sandy and peaty substrate. The waters are tannin stained, slow flowing, and acidic (pH 4.5, as measured in February 2009). Syntopic species recorded from the type locality include: Boraras maculatus , Cyclocheilichthys apogon , Osteochilus spilurus , Parachela maculicauda , P. oxygastroides , Rasbora einthovenii , R. trilineata , Systomus johorensis , Trigonopoma gracile , T. pauciperforatum (Cyprinidae) , Lepidocephalichthys furcatus , Pangio alcoides , P. semicincta (Cobitidae) , Kryptopterus macrocephalus , Ompok leiacanthus , Wallago leerii (Siluridae) , Hemibagrus nemurus , Pseudomystus leiacanthus (Bagridae) , Clarias batrachus , C. meladerma (Clariidae) , Parakysis verrucosa (Akysidae) , Aplocheilus panchax (Aplocheilidae) , Hemirhamphodon pogonognathus (Hemiramphidae) , Monopterus albus (Synbranchidae) , Nandus nebulosus (Nandidae) , Pristolepis grooti (Pristolepididae) , Belontia hasseltii , Betta imbellis , B. waseri , Luciocephalus pulcher , Parosphromenus paludicola , Trichopodus leerii , T. trichopterus , Trichopsis vittata (Osphronemidae) , Channa bankanensis , C. lucius and C. striata (Channidae) ( Kottelat et al., 1992; unpublished data).

Etymology. – Cheeya and Beiya, are two Chinese deities who hunt ghosts for Yama; “chee” and “bei” mean seven and eight, respectively, and “ya” is an honorable title for a respected person. Cheeya is tall and Beiya is short; in allusion to its relatively larger size as compared to B. dorsiocellata . A noun in apposition.