Lim, Motomura & Gambang, 2010
Polydactylus luparensis, a new species of threadfin (Perciformes: Polynemidae) from the Batang Lupar River, Sarawak, Borneo, MalaysiaAbstract
A new species of large-sized brackishwater threadfin, Polydactylus luparensis, is described from the Batang Lupar River in Sarawak, Malaysia, Borneo on the basis of 5 specimens (610–715 mm standard length). The new species can be distinguished from all other Polydactylus by having 8 dorsal-fin spines, first spine tiny, second spine very strong (its width more than 5 times the width of remaining spines); 13 second dorsal-fin soft rays; 11 anal-fin soft rays; 12 pectoralfin rays, its length 22–24% (mean 23%) of SL, posterior tip not reaching a vertical through posterior tip of depressed pelvic fin; 6 pectoral filaments, fourth or fifth filament longest, its length 77–85% (mean 81%) of SL, posterior tip extending slightly beyond caudal-fin base; pored lateral-lined scales 67–75 (mean 71); lateral line unbranched, extending onto upper end of lower caudal-fin lobe; 6 scale rows above lateral line, 8 below; 14 gill rakers on upper limb, 18 on lower limb, 32 in total; occipital profile concave; posterior margin of maxilla extending considerably beyond a vertical through posterior margin of adipose eyelid; depth of posterior margin of maxilla 4–5% (mean 5%) of SL, greater than orbit diameter; well-developed swimbladder present; basal half of third to sixth pectoral filament white, becoming black distally. Polydactylus luparensis is currently known only from the mouth of the Batang Lupar River.
P. K. A. Lim, H. Motomura & A. C. Gambang
Zootaxa 2405: 63–68 (2010)