Systellaspis debilis (A. Milne-Edwards, 1881 )

Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, Zootaxa 3371, pp. 1-307 : 47-48

Systellaspis debilis (A. Milne-Edwards, 1881)

( Fig. 11E)

Acanthephyra debilis A. Milne-Edwards, 1881: 13 .

Systellaspis debilis . — Chace 1940: 181, text fig. 51;1986: 65, figs. 34g –i, 35e, f. — Crosnier & Forest 1973: 87, figs. 26b, 27b. — Krygier & Pearcy 1981: 89. — Baba et al. 1986: 90, fig. 50. — Hendrickx & Estrada-Navarrete 1989: 116. — Wicksten 2002: 137.

Diagnosis. Rostrum elongated, much longer than scaphocerite, with 14 dorsal, 9 ventral teeth, acute apex. Carapace with antennal, branchiostegal teeth. Eye pigmented. Stylocerite about as long as eye. Scaphocerite with lateral tooth longer than blade. Third maxilliped about as long as first pereopod. Exopods of third maxilliped, all pereopods about same length. Pereopods 1, 2 short, chelate; pereopods 3, 4 longer, with simple dactyls, pereopod 5 shorter, with paddle-like dactyl, pereopods 3–5 with spinules on propodus, merus, ischium. Abdominal somites with rounded to blunt pleura. Abdominal somite 3 with large posterior dorsal tooth, carina; somite 4 with smaller tooth, carina. Posterior margins of somites 3, 4 armed with spinules. Somite 6 with posterolateral point. Telson nearly as long as uropods, with 5–6 pairs lateral spinules. Carapace length to 17 mm.

Color in life. Adult scarlet-red, appendages tinged with salmon-orange; line of dark photophores along ventrolateral surface of carapace, scattered photophores on lateral surface of carapace and abdominal pleura. Hardy (1970 pl. 17-7) illustrated a juvenile with the anterior part of the body scarlet and the rostrum and posterior parts fading to translucent.

Habitat and depth. Pelagic, 0–1500 m, concentrated at 150 m by night, 650–800 m by day.

Range. Indo-West Pacific, Oregon, Gulf of Mexico , Caribbean Sea, Atlantic Ocean. Type locality Bahamas Channel .

Remarks. This is one of the most common midwater shrimp.