Vemacumella heardi, Petrescu, 2001

Petrescu, I., 2001, New deep-sea Nannastacidae (Crustacea, Cumacea) from the Eastern Pacifc collected by R. V.`Vema’, Journal of Natural History 35 (11), pp. 1657-1680 : 1677-1678

Vemacumella heardi n. sp.

(figures 15, 16)

Material. HOLOTYPE immature male ( AMNH 18050 ), sta. V-17-8, 3.06 mm body length (partially dissected).

Type locality. 43 ° 14 ' S, 75 ° 27 ' W, 3219 m depth, SE Pacific Ocean , collected by R.V. ‘Vema,’ 23 M arch 1961.

Etymology. This species is dedicated in honour of the American specialist in Cumacea, Dr Richard W. Heard, as sign of great appreciation of his work and of his personal qualities.

Description of immature male. Integument granulous. Carapace (figures 15A,B) 37% of entire body length, with three strong dorsal spines and few setae; ocular lobe without evident lenses, not reaching tip of pseudoro strum; notch evident; ventral margin serrated in anterior half. Pseudorostrum short, slightly upturned, with long medially separated siphons. Antenna 1 (figure 15C) with slender articles, second article of peduncle with tubercle with two long sensory setae; main fl agellum with two articles; accessory fl agellum with three articles not exceeding basal article of main fl agellum (figure 15D). M andible (figure 15E) pars incisiva with four teeth; lacinia mobilis with three teeth; six plumose spiniform setae between lacinia and pars molaris; pars molaris truncated, robust, with anterior tooth. Maxilla 1 (figure 15F) outer endite with six simple robust setae; thick palp with two glabrous fi laments. Maxilla 2 (figure 15G) with one fi xed and two movable endites and row of fi ne setae on inner margin of protopod. M axilliped 1 (figure 15H) endite of basis with heavy setae and pair of retinacula; carpus with fi ve fl attened hand-like setae on inner margin; propodus with two serrated setae on inner margin; broad dactylus with four terminal small setae. Maxilliped 2 (figure 16A) basis with strong long plumose seta on inner distal corner; merus bulky and also with long plumose seta; carpus with plumose setae; dactylus bulky with strong terminal spine. Maxilliped 3 (figure 16B) basis with outer process with two long plumose setae, inner margin serrated; merus with inner tooth and outer tooth; carpus as long as merus, with tooth on inner distal corner; dactylus claw short. Pereopod 1 (figure 16C) basis with two long slender teeth on inner margin; ischium and merus short; carpus longer than merus and propod us; dactylus with long terminal setae. Pereopod 2 (figure 16D) basis with strong teeth on outer margin; carpus with two short setae on inner distal corner; dactylus 2.66 times as long as propodus, with few simple setae, terminal setae simple. Pereopod 3 (figure 16E) with basis longer than half of pereopod. Pereopods 4 and 5 (figures 16F,G) with progressively shorter bases and longer carpi. Exopods on maxilliped 3 and pereopods 1–4. Uropod (figure 16H) with peduncle 1.7 times as long as last pleonite, 1.3 times as long as endopod, with teeth and four setae on inner margin, small setae on outer margin; exopod 85% of endopod length, with long simple terminal seta; endopod with fi ve robust setae on inner serrated margin, strong terminal seta.

Remarks. This new species resembles the species of Styloptocuma from the deep Atlantic or eastern Pacific with spiny carapaces: S. acuminatum ( Jones, 1984) , S. bacescui ( Petrescu, 1991, Petrescu and Watling, 1999), S. gracillimum ( Calman, 1905) with regard to the carapace, antenna 1 and maxilliped 1 and 2. It diOEers in having a shorter ocular lobe (all species of Styloptocuma have ocular lobe as long or even longer than pseudorostral lobes), an accessory fl agellum with three (instead of two) articles (Petrescu, in press), the special stout seta on the propodus of maxilliped 1, and a process on the basis of maxilliped 3.