Tuesday, May 26, 2020

[Ichthyology • 2020] Plectranthias purpuralepis • A New Anthiadine Perchlet (Perciformes: Serranidae) from northern Taiwan


Plectranthias purpuralepis 
 Tang, Lai & Ho, 2020


Abstract
A new species of Plectranthias Bleeker is described on the basis of 16 specimens collected from northern Taiwan. The new species, Plectranthias purpuralepis sp. nov. can be distinguished from its congeners in having pectoral and pelvic fins mostly covered with small scales, some white scales on dorsum turn purple when preserved, and the following combination of characters: dorsal-fin elements X, 16–17; 3rd dorsal-fin spine longest; pectoral-fin rays 14, all branched except for uppermost simple ray; principal caudal-fin rays 9+8; pored lateral-line scales 33–36; 6 diagonal rows of large scales on cheek; circumpeduncular scales 14; ca. 7 rows of large predorsal scales, 2 irregular rows of small scales extending to a line through posterior nostrils; no scales on maxilla and chin; posterior margin of preopercle serrated, ventral margin with 2 antrorse spines; and the greatest body depth 2.9–3.0 in SL.

Keywords: Pisces, Teleostei, Actinopterygii, taxonomy, ichthyology

FIGURE 1. Fresh coloration. A. Plectranthias purpuralepis sp. nov., NMMSTP002339, 143.8 mm SL, holotype. B. P. sheni, NMMSTP002342, 120.5 mm SL. C. P. kamii, NMMSTP002338, 152.9 mm SL.

FIGURE 2. Paratypes of Plectranthias purpuralepis sp. nov. A. NMMB-P32943, 143.6 mm SL; B. NMMB-P33386, 144.7 mm SL; C. NMMB-P32937, 146.6 mm SL.

Plectranthias purpuralepis sp. nov. 
New English name: Purple-scaled perchlet

Diagnosis. A species of Plectranthias with pectoral and pelvic fins mostly covered by small scales and scales on the whitish pink blotches turn purple when preserved. It can be further separated from congeners by having the combination of following characters: dorsal-fin elements X, 16–17; 3rd dorsal-fin spine longest; pectoral-fin rays usually 14, all branched except for uppermost ray simple; principal caudal-fin rays 9+8; pored lateral-line scales 32–36; 6 diagonal rows of large scales on cheek; circumpeduncular scales 14; ca. 7 rows of large predorsal scales, 2 irregular rows of small scales extending to a line through posterior nostrils; no scales on maxilla and chin; posterior margin of preopercle serrated, ventral margin with 2 antrorse spines; and greatest body depth 32.6–35.1% SL.


Distribution and habitat. Only known from northern Taiwan, near the “Three Northern Islands,” collected by anglers at depths of 200 m or below, judging from other specimens collected together, such as Parapercis spp., Plectranthias kamii, P. sheni, and Helicolenus hilgendorfii (Döderlein, 1884). The habitat of this species is assumed to be rocky reef bottom or slope in the mesophotic zone.

Etymology. The specific name purpuralepis is a combination of the Latin “purpura” and “lepis,” meaning purple scales, in reference to the distinct purple color only present after preservation. The name is treated as a noun in apposition.



Chi-Ngai Tang, Nok-Wai Lai and Hsuan-Ching Ho. 2020. Plectranthias purpuralepis sp. nov., A New Anthiadine Perchlet from northern Taiwan (Perciformes: Serranidae). Zootaxa. 4780(3); 508–522. DOI: 10.11646/zootaxa.4780.3.4