A new wriggler of Eleotrid (Teleostei: Xenisthmidae) from Taiping Island, South China Sea

A new wriggler of genus Xenisthmus was collected from Taiping Island, South China Sea, Taiwan, while SCUBA diving for a coral reef fish survey. The new species, Xenisthmus aureus sp. nov., can be well distinguished from other congeners by the following unique combination of features: (1) fins: second dorsal fin rays I/11; anal fin rays I/10; pectoral fin rays15; (2) squamation: longitudinal scale series 60–62; perdorsal scales 0; (3) vertebral count 10+16=26; (4) preopercular canal present with 4 pores γ, δ, ε, and ε1; and (5) specific colouration: lateral side of trunk with an upper horizontal series of 20–22 yellow spots; a median series of oblique golden yellow stripes or becoming smaller, irregular golden yellow marks; the orange red cross mark on eye, radiating into mouth and posterior area horizontally, and extending up to top eye margin to downward vertically behind the maxillary on cheek; pectoral fin base with a upper, large oblique golden yellow mark; and caudal fin base with a very small median black spot.

A species comparison of other congeners will also be briefly discussed in this paper.