Aphotopontius atlanteus Humes, 1996

Ivanenko, Viatcheslav N., Arbizu, Pedro Martínez & Stecher, Jens, 2006, Copepods of the family Dirivultidae (Siphonostomatoida) from deep­sea hydrothermal vent fields on the Mid­Atlantic Ridge at 14 ºN and 5 ºS, Zootaxa 1277, pp. 1-21 : 17

Aphotopontius atlanteus Humes, 1996

Syn. A. temperatus Humes, 1997

Material examined: 2 ΨΨ, Mid­Atlantic Ridge, Logachev­1 hydrothermal field, IRINA II site, sample 38 ROV­4, 14°45.19’N, 44°48.75’W, depth 3036 m, musselbed of Bathymodiolus puteoserpentis , southwest of smoker­complex, 26 January 2004. 27 ΨΨ, sample 35 GTV, 14°45.19’N, 44°58.75’W, depth 3019 m, musselbed of Bathymodiolus puteoserpentis near smoker­complex, 26 January 2004 ( Fig. 1 A).

Differential diagnosis. Anterior part of genital double­somite laterally expanded and rounded. Caudal rami with ratio 1.9: 1 in female, 1.4: 1 in male. Leg 1 with inner coxal seta and with rounded inner margin of basis. Endopodal segment 3 of leg 2 with 2 terminal setae (formula 1,2,3) in female and 2 terminal spines (1,II,3) in male.

Remarks. The copepods of the genus Aphotopontius are not known in the western Pacific, but are common in the eastern Pacific: Nine of 10 species were recorded from eight sites situated from the equator (Galapagos Rift) to the 49°N (Explorer Ridge). A second species of Aphotopontius from the MAR, A. forcipatus Humes, 1987 , was described from the Explorer Ridge and later recorded from the Snake Pit on the MAR ( Humes 1996), the Gorda Ridge ( Humes 1990b) and the Juan de Fuca Ridge ( Humes & Huys 1992). The species can be distinguished from Aphotopontius atlanteus by the elongate caudal ramus (ratio 5.6:1) among other attributes.

Aphotopontius atlanteus was previously recorded in many samples from Lucky Strike and Menez Gwen at 37°N ( Humes 1996; Humes 1997; Humes & Segonzac 1998). Aphotopontius temperatus Humes, 1997 described from Lucky Strike was synonymized with A. atlanteus by Ivanenko and Defaye (2006b).

Figures

FIGURE 1. Mid­Atlantic Ridge: A, Logachev hydrothermal field at 14 ° N, IRINA II site, musselbed of Bathymodiolus puteoserpentis, at the southwest from the smoker­complex; B, Turtle Pits hydrothermal site at 5 ° S, active chimney “ Tower ” with alvinocaridid shrimps of different size. (Photos courtesy by MARUM © 2005, University of Bremen.)