Labriphimedia martinae, Coleman & Lörz, 2013

Coleman, Charles Oliver & Lörz, Anne-Nina, 2013, Iphimediidae of New Zealand (Crustacea, Amphipoda), European Journal of Taxonomy 62, pp. 1-18 : 10-16

Labriphimedia martinae sp. nov.

Figs 7-11

urn:lsid:zoobank.org:act:D8ED7489-8474-4E50-9856-27119A69E933

Material examined

Holotype

♂, 6.5 mm, NIWA 84743 .

Locus typicus

NEW ZEALAND: TAN0705/136, 14 April 2007, 43°17’25ˮ S, 175°33’08ˮ W – 43°17’36ˮ S, 175°33’47ˮ E, 638- 644 m.

Etymology

This species is named for the amiable Ms Martine Willcox, the mother of the son-in-law of the senior author.

Description

LENGTH. Based on male holotype, 6.5 mm.

HEAD ( Fig. 7A ). Eyes ovate; rostrum strongly curved; anterior margin with angular spine, anteroventral corner with an acute long narrow spine. Antenna 1 ( Fig. 7 C-D) peduncular article 1 with a long distomedial spine and a small anterodistal spine; peduncular article 2 with longer dorsal and small spine, with an anterodistal spine; accessory flagellum present, accessory flagellum 1-articulate; article 3 with anterodistal process; article 4 subequal to 3. Antenna 2 ( Fig. 7G ) articles 2 and 3 serrate distomedially. Mouthparts arranged in a cone. Upper lip ( Fig. 7B ) tapering distally, apex asymmetrical. Mandibular body ( Fig. 7E, F, I, H ) tapering distally; incisor not dentate; lacinia mobilis on right side rather stout; molar not triturative, but protruding; palp 3 articulate, ratios of articles 1-3 1:2.75:1.5. Lower lip ( Fig. 8A ) inner lobes absent; lobes tapering distally into pointed apex. Maxilla 1 ( Fig. 8 D-E) palp 1-articulate, much shorter than outer plate, very small scale with an apical seta. Maxilla 2 ( Fig. 8 B-C, F) inner lobe considerably shorter than outer. Maxilliped ( Fig. 8 G-J) inner lobe elongate, surpassing the distal margin of 1st palp article, with setae on the apex and 2 rows of setae along the medial margin; outer plate

tapering distally, bordered with plumose setae apically; palp consisting of 3 long articles and 1 minute distolateral article; 2nd palp article expanded distomedially.

PEREON ( Fig. 7A ). Pereonite 1 enlarged, 3-4 x as long as pereonite 2. Pereonites 5-6 posteroventral angle acute; that of pereonite 7 pointed and drawn out. Pereonite 7 without mid-dorsal carina, dorsodistal margin with 2 large pointed spines, space between spines widely excavate, with 1 posteroventral spine. Gnathopod 1 ( Fig. 9 A-B) coxa subrectangular, ventrally truncated and serrate; basis slightly longer than coxa; carpus somewhat longer than propodus, both carpus and propodus narrow; setation restricted to anterior margin of basis and region of chela. Gnathopod 2 ( Fig. 9 C-D) slightly shorter than gnathopod 1; coxa tapering, ventrally truncated, ventral margin with 2 notches with microtrichs; carpus and propodus subequal in length, strongly setose; Pereopod 3 ( Fig. 9 E-F) coxa ventrally rounded, ventral margin weakly serrate; basis and ischium with rounded lobe distomarginally. Pereopod 4 ( Fig. 10 A-B) coxa wide, apically rounded, with angular posteroventral corner, ventral margin serrate; posterior margin with rounded lobe; basis and ischium with rounded lobe distomarginally. Pereopod 5 ( Fig. 11A ) coxa wider than long, bilobate, posterior margin pointed; basis subrectangular, posterior margin straight, weakly serrate, posteroventral corner subquadrate, anterodistal angle pointed; ischium anterodistal angle pointed; merus drawn out posterodistally; carpus expanded distally, slightly shorter than propodus; dactylus not curved much, with small unguis. Pereopod 6 ( Fig. 10D ) coxa bilobate, anterior lobe shorter, with posteroventral spine; basis anterodistally pointed, posterodorsal corner subquadrate, posterior margin weakly serrate, posteroventral corner with small spine; ischium and merus as for pereopod 5. Pereopod 7 ( Fig. 10C ) coxa with posteroventral spine; basis anterodistally pointed, posterodorsal corner rounded, posterior margin weakly serrate, posteroventral corner with large spine; merus and carpus as for pereopod 5.

PLEON ( Fig. 7A ). Pleonite 1 with a low, truncated mid-dorsal carina with a small posterior point, with 2 large, pointed spines, space between spines wide. Epimeron 1 posterior margin with 1 mid-lateral spine, posteroventral corner acutely with short point. Pleonite 2 with a low truncated mid-dorsal carina with a small posterior point, dorsodistal margin with 2 large, pointed spines, space between spines wide. Epimeron 2 posterior margin with 1 mid-lateral spine, posteroventral corner pointed. Pleonite 3 with a broadly rounded, large mid-dorsal carina. Epimeron 3 posterior margin without well developed lateral spines, posteroventral corner produced into 1 smooth spine, its dorsal part minutely serrate. Urosomite 1 large with broadly rounded, large mid-dorsal carina with a shallow depression. Urosomite 2 shortest, smooth. Telson ( Fig. 11F ) truncate, with several small notches along the distal margin.

Distribution

Chatham Rise, New Zealand (South-western Pacific), 638- 644 m.

Figures

Fig. 7. Labriphimedia martinae nov. sp., holotype ♂, 6.5 mm, NIWA 84743. A. Habitus. B. Upper lip. C. Antenna 1 peduncular articles 1-2. D. Peduncular article 3 and flagellum of antenna 1. E. Left mandible, setation of palp omitted. F. Right mandibular palp. G. Antenna 2. H. Right mandibular body. I. Apical mandibular palp article. Scale bars: A = 1 mm, B-G = 100 µm.

Fig. 8. Labriphimedia martinae nov. sp., holotype ♂, 6.5 mm, NIWA 84743. A. Lower lip. B. Outer plate of maxilla 2. C. Inner plate of maxilla 2. D. Left maxilla 1. E. Palp of right maxilla 1. F. Outlines of maxilla 2. G. Palp of maxilliped. H. Inner plate of maxilliped. I. Outer plate of maxilliped. J. Outline of maxillipeds. Scale bars: A-J = 100 µm.

Fig. 9. Labriphimedia martinae nov. sp., holotype ♂, 6.5 mm, NIWA 84743. A. Gnathopod 1. B. Chela of gnathopod 1. C. Gnathopod 2. D. Chela of gnathopod 2. E. Pereopod 3. F. Presumed carpus to dactylus of pereopod 3. Scale bars: A, C, E-F = 100 µm.

Fig. 10. Labriphimedia martinae nov. sp., holotype ♂, 6.5 mm, NIWA 84743. A. Pereopod 4. B. Presumed carpus to dactylus of pereopod 4. C. Pereopod 7. D. Pereopod 6. Scale bars: A-D = 100 µm.

Fig. 11. Labriphimedia martinae nov. sp., holotype ♂, 6.5 mm, NIWA 84743. A. Pereopod 5. B. Pleopod 1. C. Right uropod 2. D. Uropod 1. E. Uropod 3. F. Telson. Scale bars: A-F = 100 µm.