Nerocila arres Bowman & Tareen 1983

Nerocila (Nerocila) arres

Material.—From Epinephalus tauvina (Forskål), caudal fin: Seif fish market, Kuwait City, 13 Feb 1977, USNM 189268, 26.2 (paratype). From Acanthopagrus latus (Houttuyn): north of platform, 29 Apr 1977, USNM 189265, ovigerous 29.0 (paratype). From Nemipterus japonicus (Bloch), caudal fin: Jan 1977, USNM 189264, ovigerous 30.5 (holotype). From Nemipterus tolu (Cuvier and Valenciennes), caudal fin: SG 611 (trawl), 12 Apr 1982, USNM 191055, ovigerous 28.4 (paratype).

ETYMOLOGY.—From serra spelled backwards, referring to its similarity to Nerocila serra.

DIAGNOSIS.—Head rounded anteriorly, produced into broad shelf anterior to antennae 1. Antennae 1 separated by 0.2–0.7 length of proximal segment. Pereopods 1–5 with swelling in dactyls (Acanthopagrus and Nemipterus specimens), or only pereopod 5 with swelling (Epinephalus specimen); dactyls of pereopods 1–5 subequal. Pereopod 3 with 3 marginal spines on propus in Nemipterus specimen, without spines in other specimens. Pereopods 6 and 7 with marginal spines. Posteroventral corners of all pereonites produced into points, those of pereonites 1–5 subequal, those of pereonites 6 and 7 progressively longer. Coxae produced into pointed processes subequal to posteroventral processes of pereonites. Pleotelson nearly 1/3 wider than long; posterior end damaged in Epinephalus and Acanthopagrus specimens, with low, broad, caudomedial lobe in Nemipterus specimen. Exopod of uropod sublinear, curving medially, slightly longer than endopod; endopod with deep notch on lateral margin and coarsely serrate medial margin.

ADDITIONAL DESCRIPTION.—Antennae 1 and 2 as in N. kisra, but segments 1 and 2 of antenna 1 may be partly fused and number of segments may differ by 1 or 2. Mouthparts not examined. Pleopods similar to those of N. kisra and N. sigani.

RELATIONSHIPS.—Uropods with serrate endopod margins have been reported in 3 species of Nerocila: N. trivittata Bleeker, 1857, N. serra Schioedte and Meinert, 1881, and N. monodi Hale, 1940. Monod considered N. serra to be a junior synonym of N. trivittata (see Niestrasz, 1931:124, footnote; Hale, 1940:301). Monod's opinion may very well be correct; the color patterns appear to be identical, and there is nothing in Bleeker's brief description and illustrations with few details that conflicts with the account of Schioedte and Meinert. The type-locality of N. trivittata is Amboina, that of N. serra Bangka, both in Indonesia. But Bleeker did not mention some important characters now known to be useful in distinguishing species of Nerocila. Hoping to better characterize N. trivittata and N. serra, we attempted to compare type material of the 2 species. From the Naturhistoriska Riksmuseet we obtained, through the courtesy of Dr. Charlotte Holmquist, one of the 2 syntypes of N. serra used by the authors in preparing the description. Unfortunately, we have not been able to locate Bleeker's single specimen of N. trivittata. It is not in the Rijksmuseum van Natuurlijke Historie, Leiden, as are specimens of Bleeker's other isopod species, and Dr. L.B. Holthuis, who kindly furnished this information, pointed out that N. trivittata was not included in Nierstrasz's (1915) account of the Cymothoidae in the Leiden Museum. It seems likely that the type of N. trivittata is not extant, and the question of the identity of N. trivittata and N. serra cannot be resolved now.



The syntype of N. serra is very similar to N. arres. Swellings are present on the dactyls of pereopods 1, 4, and 5, but not pereopod 3 (pereopod 2 lacks dactyls). Pereopod 3 has a single distal spine on the propus. It differs from N. arres in the uropodal endopod, which is longer and narrower, with a shallower notch on the medial margin, and with smaller serrations on the lateral margin. The body has 3 longitudinal dark stripes, which have persisted in preservative for more than a century. Three of our Kuwait specimens of Nerocila lack pigmentation; the specimen from Nemipterus tolu has 3 stripes as in N. serra, but lighter in shade.

Catoessa Schioedte and Meinert, 1884

Catoessa Schioedte and Meinert, 1884:309, 310. [Type-species, by monotypy, Catoessa scabricauda Schioedte and Meinert, 1884, Adonara I, Lesser Sunda Is., Indonesia. Host unknown. Deposition, Berlin Museum.]

The genus Catoessa was proposed for C. scabricauda, represented by a single ovigerous from Adonara Island, one of the Lesser Sunda Islands east of Flores Island. Schioedte and Meinert's (1884) Latin diagnosis of Catoessa contains almost nothing of generic value, and there is little justification for separating Catoessa from Lironeca on the basis of their diagnosis. However, the narrow pleonite 1 and the form of the pleura of pleonites 2–5 distinguish C. scabricauda and the new species described below from all of the more than 50 species of Lironeca, hence we continue to recognize the little known genus Catoessa as valid.