Labriphimedia meikae, Coleman & Lörz, 2013

Coleman, Charles Oliver & Lörz, Anne-Nina, 2013, Iphimediidae of New Zealand (Crustacea, Amphipoda), European Journal of Taxonomy 62, pp. 1-18 : 4-10

Labriphimedia meikae sp. nov.

Figs 2-6

urn:lsid:zoobank.org:act:BD138120-DFEB-4939-8848-7E6D79EE9B4C

Material examined

Holotype

♂, 6 mm, NIWA 84598 .

Additional material

Two paratypes of unknown sex, 5.2 mm and 5 mm, NIWA 31826, same station data as holotype.

Locus typicus

NEW ZEALAND: TAN0705/251, 24 April 2007, 42°59ˮ45’ S, 178°59ˮ44’ E – 42°59ˮ28’ S, 179°0ˮ19’ E, 520- 530 m.

Etymology

This species is named for Ms Meike Snyder, the dear aunt of the senior author.

Description

LENGTH. Based on male holotype, 6 mm.

HEAD ( Fig. 2A ). Eyes reniform; rostrum only weakly curved; anterior margin with small rounded sculptured spine (which looks pointed in dorsal view), anteroventral corner with rounded lobe. Antenna 1 ( Fig. 2B ) peduncular article 1 with a long posteroventral spine reaching the distal margin of the peduncular article 2 and a shorter dorsal spine; peduncular article 2 with short spine; peduncular article 3 and flagellum unknown. Antenna 2 ( Fig. 2D ) peduncular article 2 with short rounded gland cone and longer bifid medial process; peduncular article 4 slightly drawn out laterally; peduncular article 5 and flagellum unknown. Upper lip ( Fig. 2G ) wider than long, emarginate. Mandibles ( Fig. 2E ) with smooth incisors and a spine-like lacinia mobilis on the left mandible (the right mandible apparently does not have a lacinia mobilis); palp 3-articulate, ratios of articles 1-3 1:1.4:1.2. Lower lip ( Fig. 2C ) inner lobes absent, distally rounded. Maxilla 1 ( Fig. 3A ) inner plate with 6 plumose setae on the inner margin; outer plate with 11 spine-like serrate setae; palp 2-articulate, well developed, longer than outer plate, with 9 apical setae. Maxilla 2 ( Fig. 2F ) inner plate slightly shorter and subequal in width compared to outer plate. Maxilliped ( Fig. 3 B-E) inner plate long, rectangular with slender plumose setae apically and 2 rows mediomarginally; outer plate with tapering apex, bordered with plumose setae; palp article 1 as long as articles 2 and 3 combined; article 2 weakly produced medially, not guarding along article 3; there may be an inconspicuous 4th article.

PEREON ( Fig 2A ). Pereonite 1 enlarged, about 3-4 x as long as pereonite 2. Pereonites 5-7 with pointed and drawn out posteroventral angles. Pereonite 7 without mid-dorsal carina, dorsodistal margin with 2 large narrow pointed spines, space between spines wide. Gnathopod 1 ( Fig. 4A ) coxa ventrally acute, ventral and anterior margin smooth apart from 2 minute notches with microtrichs; basis longest; ischium elongate, slightly longer than merus; carpus slightly longer than propodus; dactylus and propodus forming a chela, inner margin of dactylus serrate apically; setation, apart some setae on basis, only on chela. Gnathopod 2 ( Fig. 4B ) larger than gnathopod 1; coxa ventrally acute, ventral and anterior margin smooth apart from 2 minute notches with microtrichs; basis longest, ischium longer than merus; merus expanded distally; carpus and propodus subequal in length; propodus with groups of setae posteromarginally and apically; distal propodus extension wider than dactylus; chelate. Pereopod 3 ( Fig. 5A ) coxa longer than preceding coxae, posteroventrally acute, ventral margin apart from 2 minute notches with microtrichs smooth; basis and ischium with rounded lobe on apical margin. Pereopod 4 ( Fig. 5B ) coxa pointed distally and posteromarginally, ventral margin smooth apart from some minute notches with microtrichs; basis and ischium with rounded lobe on apical margin. Pereopod 5 ( Fig. 5C ) coxa with long pointed posteroventral spine; basis posterior margin with 2 spines: posterodorsal spine pointed, posteroventral corner subquadrate; posterior margin weakly serrate; ischium anterodistally pointed; merus posteroventral lobe elongate; carpus to dactylus unknown. Pereopod 6 ( Fig. 6A ) of similar shape as pereopod 5, but basis wider with a pointed posteroventral corner and bearing an angular posterodorsal process. Pereopod 7 ( Fig. 6 B-C) coxa small with pointed posteromarginal spine; basis posteroventrally with spine, directed ventrally, posterior margin weakly serrate; merus posteroventral lobe elongate.

PLEON ( Fig. 2A ). Pleonite 1 without mid-dorsal carina, with 2 large, pointed spines, space between spines widely excavate, similar to the arrangement on pereonite 7. Epimeron 1 posterior margin with 1 mid-lateral spine, posteroventral corner with short point. Pleonite 2 without mid-dorsal carina; with 2 large, pointed spines, space between spines wide. Epimeron 2 posterior margin with 1 mid-lateral spine, posteroventral corner pointed. Pleonite 3 without mid-dorsal carina; dorsodistal margin with 2 straight spines, shorter than those on pereonite 7 and pleonites 1-2. Epimeron 3 posterior margin with 1 well developed lateral, smooth spine, posteroventral corner produced into smooth spine. Urosomite 1 longest, smooth. Urosomite 2 shortest. Telson ( Fig. 6G ) emarginate.

Distribution

Chatham Rise, New Zealand (South-western Pacific), 520- 530 m.

Figures

Fig. 2. Labriphimedia meikae nov. sp., holotype ♂, 6 mm, NIWA 84598. A. Habitus. B. Antenna 1, peduncular articles 1-2. C. Lower lip. D. Antenna 2, peduncular articles 1-4. E. Left mandible. F. Maxilla 2. G. Upper lip. Scale bars: A = 1 mm, B-G = 100 µm.

Fig. 3. Labriphimedia meikae nov. sp., holotype ♂, 6 mm, NIWA 84598. A. Maxilla 1. B. Outlines of maxilliped. C. Palp of maxilliped. D. Outer plate of maxilliped. E. Inner plate of maxilliped. Scale bars: A, C-E = 100 µm, B = 200 µm.

Fig. 4. Labriphimedia meikae nov. sp., holotype ♂, 6 mm, NIWA 84598. A. Gnathopod 1. B. Chela of gnathopod 1. C. Gnathopod 2. Scale bars: A, C = 100 µm.

Fig. 5. Labriphimedia meikae nov. sp., holotype ♂, 6 mm, NIWA 84598. A. Pereopod 3. B. Pereopod 4. C. Pereopod 5. Scale bars: A-B = 100 µm. C = 200 µm.

Fig. 6. Labriphimedia meikae nov. sp., holotype ♂, 6 mm, NIWA 84598. A. Pereopod 6. B. Coxa of pereopod 7. C. Basis to merus of pereopod 7. D. Uropod 3. E. Uropod 2. F. Uropod 1. G. Telson. Scale bars: A-C = 200 µm, D-G = 100 µm.