Pygodelphys antarctica

• Main Authors: Kim, Il-Hoi, Boxshall, Geoff A.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2020
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Maxillopoda; Cyclopoida; Notodelphyidae; Pygodelphys; Pygodelphys antarctica; Argentina; Seta; Antarc*; Antarctica; Tierra del Fuego
• Online Access: https://zenodo.org/record/5661673; https://doi.org/10.5281/zenodo.5661673

Pygodelphys antarctica (Schellenberg, 1922) (Figs. 60, 61) Material examined. 53 ♀♀, 40 ♂♂ (MNHN-IU-2018- 1779) and dissected 1 ♀, 1 ♂from Paramolgula gregaria (Lesson, 1830), Magellan Strait; 4 ♀♀ (MNHN-IU-2018- 1780) and 1 dissected ♀ from P. gregaria, Tierra del Fuego, Argentina. Supplementary description of female. Body (Fig. 60A) Doropygus -like in form, relatively slim. Body length 5.15 mm. First to third pedigerous somites each with well developed dorsal tergite. Brood pouch of fully grown adults shorter than anterior part of prosome; fifth pedigerous somite incorporated into brood pouch. Freeurosome (Fig. 60B) slender, clearly 5-segmented; comprising short genital somite, 160×516 μm and 4 free abdominalsomitesgraduallyshorterand narrowertowards posterior, 501×480, 436×400, 349×356, and 255×313 μm, respectively. First and second abdominal somites ornamented with scattered rows of minute spinules on ventral surface (Fig. 60B). Caudal ramus (Fig. 60C) slender, about 6.2 times as long as wide (590×95 μm) but variable in length (in other dissected specimen 4.6 times as long as wide, 391×85 μm); armed with 6 setae, distal setae stiff, not flexible, longest seta 263 μm long, 0.45 times as long as ramus; outer lateral seta invariably located at 35% of ramus length. Rostrum (Fig. 60D) tapering, shield-shaped, longer than wide, with angular apex. Antennule 10-segmented (Fig. 30); firstandsecondsegments broadened; armature formula 3, 17, 6, 3+aesthetasc, 1, 3, 2+aesthetasc, 2, 2+aesthetasc, and 7+aesthetasc; one of distalsetae on second segment pinnate, all other setae naked. Antenna (Fig. 60F) 3-segmented, consistingof coxa, allobasis, and 1-segmented free endopod; basiswith 2 large setae of subequal length (1 pinnate and 1 naked, wrinkled) subdistally on outer margin representing exopod, and 1 seta (derived from first endopodal segment) on inner margin; free compound endopodal segment about 3.6 times as long as wide, slightly shorter than basis, and armed with 11 setae plus terminal claw, half as long as segment. ...