Iphimedia damawan, Lowry & Myers, 2003

Lowry, J. K. & Myers, A. A., 2003, New Amphipod Crustaceans From The Indo-West Pacific (Amathillopsidae: Eusiridae: Iphimediidae), Raffles Bulletin of Zoology 51 (2), pp. 219-256 : 235-238

Iphimedia damawan , new species

( Figs. 15-17 )

Material examined. – Holotype – ovigerous female, 3.6 mm, AM P64443, Dam Awan , 5 09.27’S 145 49.86’E, Madang Lagoon, Papua New Guinea, coral rubble including dead Acropora , 30 and 15 m, coll. J. D. Thomas, 17 Apr.1991, stn JDT/PNG-72h.

Paratypes – 2 specimens AM P64450, same data as above ; 3 specimens AM P64451, barrier reef near Wongad Island , 5 08.11’S 145 49.53’E, rubble encrusted dead Acropora plates, also some pieces from caves and overhangs, 36 m and 21 m, coll. J. D. Thomas, 22 Feb.1990, stn JDT/PNG-59c .

Type locality. – Dam Awan, 5 09.27’S 145 49.86’E, Madang Lagoon , Papua New Guinea .

Description. – Head laterocephalic margin without spine, ventrolateral corner an acute spine; eyes ovate. Antenna 1 peduncular article 1 with posterodorsal spines, without posteroventral spine; peduncular article 2 with small posterodorsal spine, without posteroventral spine. Maxilla 1 palp reduced, shorter than outer plate, 2-articulate.

Pereon. Gnathopod 1 coxa small, ventrally truncated, ventral margins smooth. Gnathopod 2 coxa small, ventrally truncated, ventral margins smooth. Pereopod 3 coxa posteroventrally subacute, ventral margins smooth. Pereopod 4 coxa ventral margins smooth. Pereopod 5 coxa posteroventral corner broadly rounded; basis posterodorsal corner subquadrate, posterior margin without spines, smooth, posteroventral corner rounded; merus posteroventral lobe as long as or longer than carpus. Pereopod 6 coxa posteroventral corner subquadrate; basis posterodorsal corner subquadrate, posterior margin without spines, smooth, posteroventral corner with 2 small spines; merus posteroventral lobe as long as or longer than carpus. Pereopod 7 coxa subquadrate; basis posterodorsal corner subquadrate, posterior margin without spines, strongly serrate, posteroventral corner with small spine; merus posteroventral lobe produced about halfway along carpus. Pereonite 7 without mid-dorsal carina, dorsodistal margin slightly to strongly produced, with 2 small posterior spines.

Pleon. Pleonite 1 without mid-dorsal carina, dorsodistal margin strongly produced, shield-like, with 2 large spines. Pleonite 2 with a broadly rounded low mid-dorsal carina, dorsodistal margin not produced, with 2 large spines. Pleonite 3 without mid-dorsal carina, dorsodistal margin not produced, with 2 straight spines. Epimeron 1 posterior margin without mid-lateral spines; posteroventral corner rounded. Epimeron 2 posterior margin without mid-lateral spines, posteroventral corner produced into a spine. Epimeron 3 posterior margin with 1 ventrolateral, recurved, smooth spine, posteroventral corner produced into a, smooth spine. Telson notched, slightly longer than broad, parallel sided, with pair of distal fine setae.

Remarks. – The posteroventral corner of pereopod 6 basis is unique among the described species of Iphimedia in having two small spines. In addition the combination of a subquadrate posterodorsal corner on the basis of pereopod 6 and a strongly produced, shield-like dorsodistal margin on pleonite 1 further distinguishes this species from all others.

Distribution. – Papua New Guinea.

Etymology. – Named for Dam Awan, the type locality.

Figures

Fig.15. Iphimedia damawan, new species, ovigerous female, 3.6 mm, AM P64443, Dam Awan, Madang Lagoon, Papua New Guinea.

Fig.16. Iphimedia damawan, new species, ovigerous female, 3.6 mm, AM P64443, Dam Awan, Madang Lagoon, Papua New Guinea. Scale bar = 0.1mm.

Fig.17. Iphimedia damawan, new species, ovigerous female, 3.6 mm, AM P64443, Dam Awan, Madang Lagoon, Papua New Guinea. Scale bar = 0.1mm.