Abstract
The slender snake eel genus Yirrkala from Taiwan is reviewed, and a total of four species are recognized, including a new species described here. Yirrkalankust sp. nov. is described based on four specimens collected from western Taiwan. It can be distinguished from congeners by the dorsal-fin origin situated above the gill opening, the tip of lower jaw not reaching the base of the anterior-nostril tube, 1 + 3 supraorbital pores, 7-8 predorsal vertebrae, and 147-152 total vertebrae. Two rare species, Yirrkalakaupii Bleeker, 1858 and Yirrkalaomanensis Norman, 1939, are redescribed based on specimens newly collected from Taiwan. A key to all Yirrkala species found in Taiwan is provided.