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D.J. SIEBERT AND A.H. TJAKRAWIDJAJA 
Fig. 7 Schismatorhynchos endecarhapis: A. MZB 6092, holotype, 179.0 mm SI; B. S. endecarhapis, BMNH 1993.5.12:1—19, paratype, juvenile, 59.4 mm 
SI. 
111°38.5'E; rotenone; T.R. Roberts; 26 July 1976; field no. Kapuas 
1976-29. MZB 3433 (2); Sungai Pinoh 37 km S of Nagapinoh; 
0°39.5'S 111°40'E; rotenone; T.R. Roberts; 24 July 1976; field no. 
Kapuas 1976-27. 
DIAGNOSIS. A species of Schismatorhynchos with 11 branched rays 
in dorsal fin (S. heterorhynchos and S. holorhynchos with eight 
branched rays in dorsal fin); snout entire (S. heterorhynchos with 
cleft snout); tubercles conical, simple (S. heterorhynchos with py- 
ramidal tubercles, S$. holorhynchos with multicuspid tubercles); 
gape not reaching vertical from anterior margin of eye (S. 
heterorhynchos and S. holorhynchos with gape reaching to beyond 
anterior margin of eye); modally 33 pored lateral line scales (S. 
heterorhynchos usually with 31—32 pored lateral line scales, S. 
holorhynchos usually with 31 pored lateral line scales). 
DESCRIPTION. Material available for study consists of small speci- 
mens and one larger individual (holotype). The gap in size between 
the largest of the smaller material and the holotype is so large that 
study of allometry and shape change with size is not feasible. The 
overall form of Schismatorhynchos endecarhapis is shown in Figure 
7. Selected meristic, morphometric, and vertebral data are presented 
in Tables 1-3. 
Head length moderate (Table 1); gape reaching to a little before 
anterior margin of eye; snout with well developed rostral cap. Two 
pairs of barbels, anterior barbel in grove on snout, shorter than 
posterior barbel; posterior barbel about equal to eye diameter. 
Mouth crescentic, more than twice as wide as long (mean Mw:M1 
= 2.4; range 2.2—2.8; SE 0.08; n=9). Upper lip well separated from 
rostral cap, not continuous with lower lip around corner of mouth. 
Lower jaw with a sharp horny covering. Median lobe of lower lip 
wide, covering most of lower jaw, continuous with isthmus, sepa- 
rated from well developed lateral lobes of lower lip by a deep post 
labial grove. 
Only a single large specimen of this species is known; observa- 
tions of the extent of tuberculation are thus limited in scope. Small 
individuals with a few small tubercles, large individual with many 
small tubercles. Snout tuberculate, a small patch of large, unicuspid, 
conical tubercles present just above and before rostral barbel (Fig. 
3C). Smaller tubercles present around anterior face of rostral cap. 
No large tubercles on Jo | nor in space between nares and eyes. Fine 
tubercles present over dorsal surface of head but appear to be absent 
between nape and dorsal fin. 
Dorsal fin long, with 11 branched fin-rays (1 individual with 10, 
1 individual with 12), origin well in advance of pelvic fins. Margin 
