Penaeus (Oleopenaeus), 2023

Chan, Tin-Yam, 2023, New subgeneric names for the most commercially important shrimp genus Penaeus Fabricius, 1798 (Crustacea, Decapoda, Penaeidae), ZooKeys 1141, pp. 29-40 : 29

Penaeus (Oleopenaeus) subgen. nov.

Type species.

Penaeus latisulcatus Kishinouye, 1896.

Gender of subgenus.

Masculine.

Diagnosis.

Rostrum generally armed with 1 ventral tooth. Median sulcus at postrostral carina deep, long, about half carapace length. Adrostral sulcus as wide as postrostral carina, extending to near posterior margin of carapace. Gastrofrontal carina distinct, with posterior end turning anterodorsally. Cervical carina with dorsal end a distance from dorsal carapace. Hepatic carina distinct. First pereiopod with ischial spine minute or absent. Fifth pereiopod bearing exopod. Sixth abdominal somite completely lacking dorsolateral sulcus. Telson with 3 pairs of lateral spines. Thelycum closed.

Etymology.

The name Oleopenaeus (from the Latin olea for olive coloured) refers to the more or less uniform greenish-yellow body coloration of this group of Penaeus shrimps.

Species included.

Penaeus (Oleopenaeus) hathor Burkenroad, 1959, Penaeus (Oleopenaeus) latisulcatus Kishinouye, 1896, Penaeus (Oleopenaeus) plebejus Hess, 1865.

Remarks.

This taxon corresponds to "gen. nov. 3" in the 11-genus scheme of fig. 3 in Yang et al. (2023). Except for the shape of the thelycum and body coloration, this subgenus is morphologically very similar to Penaeus (Marsupenaeus) (see Chan1998; Tsoi et al. 2014). The thelycum is of the normal closed type in Penaeus (Oleopenaeus) subgen. nov. but pouch-like in Penaeus (Marsupenaeus) . With regards to the colour in life, the body is not banded in Penaeus (Oleopenaeus) subgen. nov. but is covered with thick cross bands in Penaeus (Marsupenaeus) . The taxonomic status of P. (O.) hathor is still uncertain if it merely represents a subspecies of P. (O.) latisulcatus or even a synonym of the latter, as both morphological and genetic differences between these two taxa are rather minor ( Holthuis 1980; Miquel 1984; Chan 1998; Ma et al. 2011; 0.8% sequence divergence in COIb 512 bp, Yang et al. 2023: table 1).