Friday, October 27, 2017

[Ichthyology • 2017] Pseudochromis stellatus • A New Species of Dottyback (Teleostei: Pseudochromidae) from Indonesia


    Pseudochromis stellatus
 Gill, Allen & Erdmann, 2017


Abstract

The Pseudochromis reticulatus complex is diagnosed to include species of Pseudochromis with the combination of a pointed caudal fin (rounded with middle rays produced), a reticulated colour pattern on the upper part of the body, dorsal-fin rays modally III,26, anal-fin rays modally III,15, and pectoral-fin rays modally 18. Members of the complex include P. reticulatus Gill & Woodland, P. pictus Gill & Randall, P. tonozukai Gill & Allen, P. jace Allen, Gill & Erdmann and P. stellatus new species. The last-named is herein described from six specimens from Batanta and Batu Hitam in the Raja Ampat Islands, West Papua, Indonesia. It is distinguished from other members of the complex in live coloration, and in having higher mean numbers of scales in lateral series and of anterior lateral-line scales (36–38 and 29–32, respectively), and a deeper body as measured from the dorsal-fin origin to pelvic-fin origin (31.8–33.5 % SL).

Keywords:  Pisces, taxonomy, Pseudochromis reticulatus complex, Raja Ampat Islands


 Pseudochromis stellatus, Batu Hitam, Raja Ampat Islands, Indonesia.
Photo by M.V. Erdmann. 

 Pseudochromis stellatus sp. nov. 
Greenhead Dottyback 

Diagnosis. A species of Pseudochromis with the following combination of characters: dorsal-fin rays III,24– 26 (usually III,26); anal-fin rays III,15; pectoral-fin rays 18–19, usually 18; scales in lateral series 36–38; circumpeduncular scales 16; caudal fin pointed (rounded with middle rays extended to form slight to obvious point); and dorsal-fin origin to pelvic-fin origin 31.8–33.5 % SL.

Etymology. The specific epithet is from the Latin, meaning starry or starred, and alludes to the yellow spots on the upper part of the body. The name was selected by high school students as part of a science activity in the Macleay Museum.


Habitat and distribution. Pseudochromis stellatus is known from Batanta and Batu Hitam in the northern Raja Ampat Islands of West Papua Province, Indonesia, where it has been collected in 55–62 m and observed to at least 70 m depth. The new species is found on deep reef slopes with gentle incline but exposed to strong currents, and is generally found in association with small gorgonian sea fans or low-growing barrel sponges. It is most likely more widely distributed in the region, but confusion with similar yellow-spotted pseudochromids makes underwater identification difficult (see Comparisons). The species possibly ranges to Cebu, Philippines (see Remarks).


 Anthony C. Gill, Gerald R. Allen & Mark V. Erdmann. 2017. Pseudochromis stellatus, A New Species of Dottyback from Indonesia (Teleostei: Pseudochromidae). Zootaxa. 4338(2); 333–340.  DOI:  10.11646/zootaxa.4338.2.7