Aristias excavatus Kilgallen, 2010, sp. nov.

Aristias excavatus sp. nov. (Figs 1–4) Type material. Holotype, male 10.25 mm, NIWA 58157, Ross Sea, 76º45.54’S, 167º49.33’E, 724–752 m, taken from the sponge Myxodoryx hanitschi (Kirkpatrick, 1907) (Demospongiae, Poecilosclerida, Myxillidae) (NIWA 36399), bottom fishing trawl, TAN 0802/ 70, 15 Febr...

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Bibliographic Details
Main Author: Kilgallen, Niamh M.
Format: Other/Unknown Material
Language:unknown
Published: 2010
Subjects:
Online Access:https://zenodo.org/record/5674682
https://doi.org/10.5281/zenodo.5674682
Description
Summary:Aristias excavatus sp. nov. (Figs 1–4) Type material. Holotype, male 10.25 mm, NIWA 58157, Ross Sea, 76º45.54’S, 167º49.33’E, 724–752 m, taken from the sponge Myxodoryx hanitschi (Kirkpatrick, 1907) (Demospongiae, Poecilosclerida, Myxillidae) (NIWA 36399), bottom fishing trawl, TAN 0802/ 70, 15 February 2008. Etymology. The specific name, excavatus, Latin, refers to the excavate anterior margin of the lateral cephalic lobes. Diagnosis. Lateral cephalic lobes broadly rounded, distinctly excavate along anterior margin; eyes apparently absent. Epistome and upper lip bounded by slight slit, upper lip projecting in front of epistome. Gnathopod 2 coxa well developed. Pereopod 3 coxa slightly expanded distally. Pereopods 5–7 with small spurs on anterodistal corner of propodus; coxa 5 and 6 producing posterior lobe, narrowly rounded ventrally. Epimeron 3 posterior margin smooth. Uropod 3 rami subequal in length; outer ramus article 2 more than half the length of article 1. Telson deeply cleft to 65% of length, lobes subtriangular. Description of male holotype. Head deeper than long; lateral cephalic lobes broadly rounded, distinctly excavate along anterior margin; rostrum absent; eyes apparently absent. Antenna 1 peduncle article 2 about half the length of article 1; flagellum missing from specimen. Antenna 2 article 3 short, subequal in length and breadth; article 4 the longest; flagellum 7+ articulate, broken at seventh article; calceoli absent. Mouthpart bundle subquadrate. Epistome and upper lip fused, bounded by slight slit; upper lip produced in front of epistome. Lower lip apically finely setose, apices of lobes pointed. Mandible molar a sparsely-setose flap; palp attached centrally, with a row of A-2 and short D-3 setae, and 3 short E-3 setae, article 3 slightly falcate, about 80% the length of article 2; incisor smooth on right mandible, slightly crenate at inner margin of left; lacinia mobilis present only on left mandible in the form of a small peg; accessory setal row absent. Maxilla 1 inner plate broad, ...