Lobocheilos

Ciccotto, Patrick J. & Tan, Heok Hui, 2018, A new species of Lobocheilos (Teleostei: Cyprinidae) from East Kalimantan, Indonesian Borneo, Zootaxa 4399 (4), pp. 543-552 : 550

Key to Species of Lobocheilos

1 Two pairs of barbels (rostral and maxillary)................................................................. 2

- One pair of barbels (maxillary)........................................................................... 4

2 12 circumpeduncular scales; 4½ scale rows between dorsal-fin origin and lateral line; Indonesia (Java)............. L. lehat

- 16 circumpeduncular scales; 5½ or 6½ scale rows between dorsal-fin origin and lateral line........................... 3

3 Edge of lower jaw arched; Indonesia (Java).......................................................... L. falcifer

- Edge of lower jaw straight; Indonesia (Borneo, Java, and Sumatra).................................. L. schwanefeldii

4 Mouth terminal; Malaysia (Borneo).............................................................. L. terminalis

- Mouth inferior........................................................................................ 5

5 No dark brown to black midlateral stripes.................................................................. 6

- One or more midlateral stripes, extending anteriorly from base of caudal peduncle to below dorsal fin to and on the operculum................................................................................................... 10

6 Long pectoral fin, reaching to, almost to, or just past pelvic-fin insertion.......................................... 7

- Shorter pectoral fin, reaching ⅔ to ¾ distance to pelvic-fin insertion............................................. 8

7 Lower jaw slightly arched; anal fin with scattered dark pigment, mostly at fin base and not dense at edge; dark brown to black spot on base of caudal peduncle in smaller specimens (90 mm SL and less); females larger than 130 mm SL with anterodorsal projection, covered with small tubercles, on head; Malaysia (Borneo)................................... L. unicornis

- Lower jaw strongly arched; distal ½ to ¾ of anal fin with dark pigment, particularly dense at edge; no dark brown to black spot on base of caudal peduncle; females without anterodorsal projection; Indonesia (Borneo)......................... L. bo

8 Dark brown to black spot at base of caudal peduncle absent or faint; tubercles on snout large, well-developed if present; Indo- nesia (Borneo) and Malaysia (Borneo)............................................................ L. erinaceus

- Distinct spot at base of caudal peduncle; tubercles on snout, if present, small, poorly-developed....................... 9

9 Small, vertically elongated oval black blotch at base of caudal peduncle; 32–33+2–3 lateral-line scales; Malaysia (Borneo)................................................................................................. L. ovalis

- Large, rounded black blotch at base of caudal peduncle; 33–36+2–3 lateral-line scales; Indonesia (Borneo).... L. kajanensis

10 Small individuals (<50 mm SL) with horizontally elongate black blotch at base of caudal peduncle and faint, thin (<¼ scale width) black stripe along midline; larger specimens with one dark brown to black midlateral stripe and one to four rows of spots, which may be fused to form stripes, extending from base of caudal peduncle anteriorly on flank and terminating any- where from underneath the dorsal fin to the humeral region, but never onto the operculum; tubercles well-developed in size in most specimens; Cambodia, Laos PDR, Peninsular Malaysia, Thailand, and Vietnam...................... L. rhabdoura

- Horizontally elongate blotch absent; single dark midlateral stripe of uniform depth (> ¾ scale width) from caudal-fin insertion onto operculum present; tubercles, if present, always small.................................................... 11

11 Mouth width small (23.5–29.9% HL); thin cream to yellow stripe on the anterior ¾ of the flank, separating the midlateral stripe from the brown dorso-lateral scales; Indonesia (Borneo)........................................... L. aurolineatus

- Mouth width large (32.1–46.4% HL); cream to yellow stripe on flank absent...................................... 12

12 Slender caudal peduncle (10.1–10.9% SL); Indonesia (Borneo)........................................... L. tenura

- Deeper caudal peduncle (11.2–12.9% SL); Indonesia (Borneo)......................................... L. ixocheilos