A review of the Australian species of Ampithoe Leach, 1814 (Crustacea: Amphipoda: Ampithoidae) with descriptions of seventeen new species Peart, Rachael A. Zootaxa 2007 2007-08-31 1566 1 1 95 66GS6 Peart, 2007 Peart 2007 [151,378,1856,1882] Malacostraca Ampithoidae Ampithoe Animalia Amphipoda 12 13 Arthropoda species cookana sp. nov.  ( Figs. 7–10)   Type material.  Holotype: AMP61832, male, 6 mm, north ledge, Cook Island, NSW, 28°11.44’S 153°34.67’E,  8 Jun 1983, 12 m, on  Chlorodesmissp., E. Ho& K. Attwood.  Paratype: AMP61833, female, 8 mm, type locality.   Diagnosis. Antenna 2 slender, similar to antenna 1, with short, dense setae on ventral margin. Lower lip with lateral lobe longer than medial lobe. Maxilla 1 inner plate with 6 slender setae. Gnathopod 1 carpal lobe truncated; carpus shorter than propodus; palm convex, without midmedial tooth, without posterodistal tooth defining palm; dactylus subequal in length to palm. Gnathopod 2 without densely setose margins; basis posterodistal lobe large and rounded, with three slender setae; carpus shorter than propodus; palm acute, excavate, without midmedial tooth, with small subacute posterodistal tooth defining palm, without defining robust setae; dactylus subequal in length to palm. Pereopod 3 basis expanded; merus narrow. Pereopods 5–7 simple. Pereopod 5 merus subrectangular. Uropod 3 peduncle with 5 distal robust setae, outer ramus shorter than inner ramus, without patch of small conical lateral denticles, without lateral setal fringe; inner ramus with 3 distal robust setae. Telsondistally truncate, apical cusps small.   Description. Based on holotypemale, 6 mm, AM P61832. Headas long as deep. Mandiblemolar with 5 or 6 robust setae in the accessory setal row; palp stout, long, setose along posterior margin, article 1 shorter than article 2 (0.34 x), article 2 longer than article 3 (1.16 x), article 3 longer than article 1 (2.53 x). Lower lipmandibular lobe with curved margins, subacute apically. Maxilla 1palp with apical robust setae. Maxilla 2inner plate narrow, outer plate broader. Maxillipedouter plate with developed setation (robust setae large).   FIGURE 9.  Ampithoe cookana  sp. nov., holotype, male, AM P61832, 6 mm. Paratype, female, AM P61833, 8 mm. Cook Island, New South Wales, Australia. Scales represent 0.5 mm.  Pereon. Gnathopod 1without densely setose margins; coxa larger than gnathopod 2 coxa, produced distoventrally, distoventral margin rounded, anterior margin straight, ventral margin with a row of small setules along ventral margin; basis shorter than coxa, with sparse (sometimes plumose) slender setae, posterodistal lobe small and rounded, 2 or 3 slender setae; merus produced to form a small, rounded distoventral lobe, anterior margin with setae absent; carpus longer than merus, subtriangular, anterior margin with more than 3 robust setae; propodus narrow (length 1.76 x width), subrectangular; palm with 1 defining robust seta; dactylus inner margin denticulate. Gnathopod 2coxa ventral margin, with a row of small setules; basis shorter than coxa, with sparse slender setae; merus produced to form a short, rounded distoventral lobe, anterior margin with setae absent; carpus longer than merus, subtriangular, anterior margin with more than 4 robust setae; propodus broad (length 1.12 x width), ovoid, not produced into an anterodistally setose lobe; dactylus tapering evenly, acute, inner margin denticulate. Pereopod 5basis with marginal robust setae, with medial slender setae; distal articles slender; propodus not expanded distally, subrectangular, with 4 distal simple striated robust setae; dactylus strongly curved. Pereopod 6basis posterior margin rounded proximally, straight distally, without marginal robust setae, without medial slender setae; merus subrectangular; propodus not expanded distally, with 3 distal simple striated robust setae; dactylus strongly curved. Pereopod 7basis with marginal robust setae, without medial slender setae; propodus defined distally by 3–5 simple robust setae.   FIGURE 10.  Ampithoe cookana  sp. nov., holotype, male, AM P61832, 6 mm. Cook Island, New South Wales, Australia. Scales represent 0.5 mm for pereopods 3, 5–7 and 0.2 mm for uropods 1–3 and telson. Pereopod 4 not illustrated, as it is identical to pereopod 3.  Pleon. Epimeron 3posteroventral corner broadly rounded. Uropod 1peduncle with more than 5 robust setae, with long setal fringe; inner ramus slightly longer than outer ramus, with more than 5 marginal robust setae, slender setae absent; outer ramus with more than 5 marginal robust setae, slender setae absent. Uropod 2peduncle with 3–5 robust setae, setal fringe absent; inner ramus slightly longer than outer ramus, with more than 5 marginal robust setae, slender setae absent; outer ramus with more than 5 marginal robust setae, slender setae absent. Uropod 3peduncle longer than broad (1.49 x width), long with respect to rami length (2.24 x), marginal robust setae absent, marginal slender setae present, with 3–5 distal slender setae; inner ramus with more than 5 distal slender setae.  Telsonwith apical and lateral slender setae.  Female(sexually dimorphic characters). Based on paratype, female, 8 mm, AMP61833. Antenna 1longer than antenna 2; peduncular article 1 subequal in length to article 2 (0.98 x), article 2 longer than article 3 (3.05 x), article 3 shorter than article 1 (0.33 x); primary flagellum with 30 articles; accessory flagellum absent. Atenna 2slender, similar to antenna 1, with short, dense setae on ventral margin; peduncular article 4 subequal in length to article 5; flagellum in complete with 6–10 articles.  Gnathopod 1subequal in size to gnathopod 2; coxa subequal in size to gnathopod 2 coxa; basis subequal in length to coxa; merus produced to form a short, subacute distoventral lobe; carpus subequal in length to propodus, anterior margin with slender setae only; palm not defined by robust setae; dactylus overreaching the palm. Gnathopod 2basis posterodistal lobe small and round, with 2 or 3 slender setae; merus produced to form a small, subacute distoventral lobe; carpus anterior margin with 1 robust seta and slender setae; palm entire, without tooth defining palm, defined by 1 robust seta.   Etymology. This species name is derived from the name of the typelocality, Cook Island.   Remarks.  Ampithoe cookana  sp. nov.resembles  A. katae  sp. nov.and  A. rachanoi Peart, 2002from Thailand, in having simple pereopods 5–7, an entire gnathopod 1 palm, gnathopod 2 has sparsely setose margins and a palm without a midmedial tooth. Of these species,  A. cookanamost closely resembles  A. katae, differing chiefly in the following features: three slender setae on the gnathopod 2 basal lobe (  A. kataehas one robust seta on gnathopod 2 basal lobe), 3 or 4 instead of 1 robust setae on the anterior margins of gnathopods 1 and 2 carpus, and the gnathopod 2 propodus bears an anterodistally setose lobe (absent in  A. katae)  Habitat.  Ampithoe cookanaoccurs in turtle grass,  Chlorodesmissp.at a depth of  12 m.   Distribution. Cook Island, New South Wales, Australia. P61832 1983-06-08 AM E. Ho & K. Attwood -28.190666 Cook Island 12 153.57784 12 13 1 holotype P61833 AM 13 14 12 13 1 paratype P61833 AM 17 18 1 paratype