Ampithoidae * Author Hughes, L. E. Author Lowry, J. K. text Zootaxa 2009 2009-10-08 2260 1 153 219 https://www.biotaxa.org/Zootaxa/article/view/zootaxa.2260.1.8 journal article 10.11646/zootaxa.2260.1.8 1175-5326 5322208 Ampithoe cookana Peart, 2007 ( Figs 1 , 2 ) Ampithoe cookana Peart, 2007b: 13 , figs. 7–10 (key). Material examined. 3 unsexed, AM P76242 (1974) ; 1 unsexed, AM P76244 ( QLD 1975 ) ; 6 unsexed, AM P76243 ( QLD 1978 ) ; 6 unsexed, AM P76241 ( QLD 1999 ) ; 1 male ‘ A’ dissected, 7.0 mm, 3 slides, AM P76240 ( QLD 2000 ) ; 1 dissected male ‘B’, 7.2 mm , 3 slides, AM P76239 ( QLD 2000 ) ; 1 female dissected, 6.5 mm , 3 slides, AM P76238 ( QLD 2000 ) . Type locality. North ledge, Cook Island , New South Wales ( 28º11.44’S 153º34.67’E ), living in Chlorodesmis sp. , 12 m . Description. Based on ‘B’ male, 7.2 mm , AM P76239. Head. Head as long as deep. Antennae 1–2 missing [in female paratype antenna 1 longer than antenna 2; peduncular article 1 subequal to article 2 with 4 robust setae along posterior margin; flagellum 29 articles; accessory flagellum absent. Antenna 2 peduncle with dense setose clumps on articles 3 to 5; article 4 subequal in length to article 5; flagellum 6+ articles]. Mandible molar well developed, triturating, accessory setal row with 5 serrate robust setae; palp 3–articulate, marginally setose; article 1 shorter than article 2, slender setae present; article 2 subequal in length to article 3. Lower lip outer plates notched, forming a medial excavation, lateral lobe distinctly longer than medial lobe; mandibular lobe with curved margins, rounded apically. Maxilla 1 inner plate with more than 4 slender setae; palp article 2 slender. Maxilliped outer plate with row of large robust setae along medial margin. Pereon. Coxae 1–4 deeper than broad. Gnathopod 1 smaller than gnathopod 2; coxa subequal to coxa 2, anteroventrally produced, anterior margin straight, anteroventral corner narrowly rounded; basis shorter than coxa, anterodistal lobe rounded, with 1 slender seta; merus posterodistal lobe acute; carpus about 1.5 x as long as broad, shorter than propodus, anterior margin with 1 robust seta, posterior margin straight; propodus narrow, subrectangular; palm transverse acute, convex, with rounded posterodistal corner, with 1 robust seta defining palm; dactylus slightly overreaching palm, inner margin crenate. Gnathopod 2 coxa without long, plumose setal fringe on ventral margin, basis with medial fringe of long, slender setae, anterodistal corner with 4 robust setae; merus margin without lobe; carpus shorter than propodus, subtriangular, with 7 robust setae along anterior margin; propodus broad, less than 1.5 x as long as broad, subrectangular, not produced into an anterodistally setose lobe; palm acute, excavate, with posterodistal tooth of medium length (length 2 x breadth), apically subacute, without palm defining robust seta; dactylus equal in length to palm, tapering evenly, apically acute, inner margin crenate. Pereopods 3–4 basis slightly expanded; merus longer than carpus. Pereopods 5–7 simple. Pereopod 6 basis posterior margin sinusoidal, with several marginal robust setae; distal articles slender; propodus not expanded distally, with 2 anterodistal striated robust setae; dactylus slightly curved. Pleon. Epimera 2–3 posteroventral corner broadly rounded. Uropod 1 peduncle with more than 13 robust setae, with short fringe of slender setae (less than 0.5 x length of peduncle), distoventral spine absent; rami subequal in length; outer ramus slender, length about 5–6 x as long as broad, with 9 marginal robust setae. Uropod 2 peduncle with 2 robust setae; outer ramus with 8 lateral robust setae; inner ramus with 9 lateral robust setae. Uropod 3 peduncle longer than broad, more than 2 x length of rami, without marginal slender setae, with 5 distal robust setae, with 5 distal slender setae; outer ramus with 2 large recurved distal robust setae, without lateral robust or slender setae; inner ramus with 6 distal slender setae, without lateral robust setae. Telson subtriangular, apically rounded, with small apical cusp on each distolateral corner, with 3 pair of lateral and1 pair of apical slender setae, and with 2 pair of lateral and 1 pair of apical plumose setae. FIGURE 1. Ampithoe cookana Peart, 2007b , male ‘A’, 7.0 mm, AM P76240, One Tree Island, Great Barrier Reef. FIGURE 2. Ampithoe cookana Peart, 2007b , male ‘A’, 7.0 mm, AM P76240, female, 6.5 mm, AM P76238, One Tree Island, Great Barrier Reef. Female (sexually dimorphic characters). Based on female, 6.5 mm , AM P76238. Gnathopod 1 subequal in size to gnathopod 2; coxa anterior margin slightly concave, anteroventral corner rounded; basis with 3 slender setae; carpus anterior margin with slender setae; palm subacute, straight. Gnathopod 2 basis anterodistal corner with 2 slender setae; palm entire, with rounded posterodistal corner, with 1 robust seta defining palm. Habitat. Chlorodesmis sp. , dead Acropora sp. coral with epiphytes. Remarks. Ampithoe cookana belongs to a group of Ampithoe species with a posterodistal tooth defining the palm of male gnathopod 2. This group includes: A. akuolaka J.L. Barnard, 1970 ; A. katae Peart, 2007b ; A. platycera Sivaprakasam, 1971 , A. rachanoi Peart, 2002 , A. waialua J.L. Barnard, 1970 and the species complex associated with A. ramondi Audouin, 1826 . Ampithoe cookana may be distinguished from these species by the male gnathopod 2 propodus which lacks the anterodistal hood and the gnathopod 1 palm which is convex. Within the GBR Ampithoe cookana is similar to A. katae , however A. katae has an anterodistal hood on gnathopod 2 and is more setose along the anterodistal propodus margin. Distribution. Australia . New South Wales : Cook Island ( Peart 2007b ). Queensland : One Tree Island (current study).