Systellaspis debilis (A. Milne-Edwards, 1881)

(Fig. 35 A–B, 36)

Acanthephyra debilis A. Milne Edwards, 1881: 13 . Miersia gracilis Smith, 1882: 70 . Systellaspis Bouvieri Coutiére, 1905: 8, fig. 3. Systellaspis debilis— Holthuis 1951: 32.— Chace 1940: 181, fig. 51; 1986: 67, figs. 34m–o, 35g, h.— Kensley 1972: 38, fig.

17b–c.— Crosnier & Forest 1973: 87, figs. 26b, 27b.— Vereshchaka 1990: 140.— Poupin 1996: 6.— Cardoso & Young 2005: 64, figs. 49–53.— Pequegnat & Wicksten 2006: 102.— Felder et al. 2009: 1053.— Poupin 2010: 73.

Material examined. 1 M, off Pernambuco, Abracos 1 ST# 51/ Leg.1, Midwater tow, 800 m, 08° 56,49’ S / 034° 29,05’ W; 08° 59,11’ S / 034° 28,62’ W, 19 October 2015, MOUFPE: 15.592.

Diagnosis: Carapace with rostrum overreaching scaphocerite, ventral margin with about ten teeth, dorsal margin with about 15 teeth; antennal spine absent; branchiostegal spine present, without distinct carina. Abdomen not dorsally carinate on all somites; somites 3 to 5 with posteromesial tooth, the one of somite 3 distinctly strong and reaching 1/4 of fourth somite. Tergum of abdominal somites 4 and 5 with markedly spinulose margin. Male pleopod 1 with endopod rounded, bilobed at apex, numerous densely articulated plumose setae on lateral margins, several hook setae at apex; male pleopod 2 with appendix masculina, little longer than appendix interna, rounded on distal portion (modified by Cardoso & Young 2005).

Distribution: Western Atlantic: south of Greenland, USA (Virginia and North Carolina), Bermuda, Gulf of Mexico, Bahamas, Caribbean Sea and Brazil (off Pernambuco and Rio de Janeiro). Eastern Atlantic: south of Iceland, Faroe Islands, Belgian, Spanish (Bay of Biscay), Portugal (Azores and Canary Islands), Cape Verde, Nigeria, Congo, Angola. Indo-Pacific Oceans: Mayotte area, Madagascar, South of the Keeling Islands, Malay Archipelago, Philippines, Indonesia, New Caledonia, Hawaii, French Polynesia (Coutiére 1905; Chace 1940, 1986; Holthuis 1951; Cardoso & Young 2005; Pequegnat & Wicksten 2006) (Fig. 36).

Bathymetric distribution: This specimen was collected in Rocas Atoll at 800 m, previous records were from 25–4594 m depth. Besides that, it is more abundant between 300–600 m (Chace 1940; Holthuis 1951; Felder et al. 2009; Cardoso & Young 2005).

Remarks: The present material has a little difference from those identified for Cardoso & Young (2005) from Brazilian waters, as follows: rostrum with 5 pre-rostral teeth projected upwards (vs 3–4) (Fig. 35B). Systellaspis debilis occurs in the Indian, Pacific and Atlantic Oceans (Fig. 36), with bathypelagic distribution (Cardoso & Young 2005). The first record in the Southwestern Atlantic was made by Cardoso & Young (2005) based on material collected from off state of Rio de Janeiro. In this paper, S. debilis is reported from the second time in Brazilian waters and for the first time in an oceanic island located in Southwestern Atlantic.