Pachychelium davidis Stephensen, 1925

Lowry, J. K. & Stoddart, H. E., 2012, The Pachynidae fam. nov. (Crustacea: Amphipoda: Lysianassoidea) 3246, Zootaxa 3246 (1), pp. 1-69 : 32

Pachychelium davidis Stephensen, 1925

Pachychelium davidis Stephensen, 1925: 121 , fig. 35. ― Stephensen, 1932: 357. ―J.L. Barnard, 1958: 97. ― Lowry, 1984: 104, fig. 42. ― Barnard & Karaman, 1991: 509. ― Palerud & Vader, 1991: 41.

not Pachychelium davidis . ―K.H. Barnard, 1932: 75: fig. 32 (= P. schellenbergi ).

Diagnostic description. Head lateral cephalic lobe large, narrowly rounded; ventral margin curved. Antenna 1 peduncular article 1 without posterodistal spine; accessory flagellum 2-articulate, article 1 long; flagellum with strong 2-field callynophore in male, [female not known]. Mandible lacinia mobilis absent; lamina dentata absent; accessory setal row absent; molar absent; palp article 2 broad, as long as article 3; article 3 tapered distally. Maxilla 1 outer plate with 4 setal-teeth in 4/0 or 3/1 arrangement, setal-teeth smooth; palp absent. Maxilliped inner plate absent; outer plate medium size; palp 3-articulate (article 4 absent), article 3 length about 2.2 × breadth. Gnathopod 1 subchelate; ischium smaller than propodus, not swollen posteroproximally; carpus extremely compressed; propodus length about 1.8 × breadth, posterior margin absent, palm without produced posterodistal corner, without robust seta. Gnathopod 2 palm minute, obtuse. Pereonite 4 without dorsal spines. Pereonite 5 without dorsal spines. Pereopod 5 merus without posteroproximal shoulder. Pereopod 6 basis with posteroventral lobe weakly produced; merus longer than broad, without posteroproximal shoulder. Pereopod 7 basis subovate with posterior margin smooth; merus, length of anterior margin 2.3 × proximal breadth. Epimeron 3 posterior margin without projections, posteroventral corner broadly rounded. Uropod 3 biramous, inner ramus just reaching base of article 2 of outer ramus. Telson shorter than broad, entire.

Distribution. Davis Strait, North Atlantic Ocean; 740 m depth.