Bamarooka tropicalis Lowry & Stoddart, 2002

Lowry, J. K. & Stoddart, H. E., 2009, Amaryllididae *, Zootaxa 2260 (1), pp. 128-131 : 128-131

Bamarooka tropicalis Lowry & Stoddart, 2002

( Figs 1 , 2 , Pl. 1A)

Bamarooka tropicalis Lowry & Stoddart, 2002: 192 , figs 58–60. –– Lowry & Stoddart, 2003: 44.

Type locality. North-west of Port Hedland, North West Shelf, Western Australia, eastern Indian Ocean (19°29'S 118°52'E) .

Material examined. 1 unsexed, AM P37094 (JML 17-10-2); 1 unsexed, AM P37095 (JML 81-26-11-4); 1 unsexed, AM P37092 (QLD 21); 4 unsexed, AM P37093 (QLD 27/28); 1 unsexed, AM P70987, 1 unsexed, AM P71010, 3 unsexed, AM P71143 and 1 male, 4.0 mm, AM P78940 (QLD 1707); 2 unsexed, AM P71114 (QLD 1710); 3 unsexed, AM P78499 (QLD 1852); 2 unsexed, AM P78498 (QLD 1869); 1 unsexed, AM P78497 (QLD 1893); 1 unsexed, AM P75656 (QLD 1918); 1 unsexed, AM P75655 (QLD 1920) .

Description. Based on male, 4.0 mm, AM P78940.

Head. Head much deeper than long, anterior margin with notch extended into a slit; rostrum absent; eye elongate, reniform. Antenna 1 peduncular article 1 not ball-shaped proximally, distal margin with small medial spine; peduncular article 2 medium length; flagellum with weak 1-field callynophore, calceoli absent. Antenna 2 flagellum about as long as that of antenna 1, with calceoli on proximal articles. Mouthpart bundle subconical. Epistome/upper lip almost straight in lateral view. Mandible lacinia mobilis a stemmed, distallycusped blade; accessory setal row with intermediate setae; palp article 2 with 1 posterodistal seta, article 3 without A3-setae. Maxilliped outer plate with distal margin smooth, medial margin without notch.

Pereon. Gnathopod 1 carpus shorter than (0.8 x) propodus; propodus, posterior margin without robust setae. Gnathopod 2 palm slightly acute, with no lateral robust setae, 1 medial robust seta. Pereopods 3 and 4 merus and carpus without setal fringe. Pereopod 4 coxa with anterior margin slightly obtuse, posterior margin rounded, anteroventral corner rounded. Pereopods 5–7 with distal articles elongate, dactyli short and stocky. Pereopod 5 basis expanded posteriorly, rounded with sloping posteroproximal shoulder. Pereopod 7 basis rounded posteriorly, posteroventral corner rounded, posteroventral margin straight.

Pleon. Epimeron 3 posterior margin smooth, with notch well above rounded posteroventral corner. Uropod 1 peduncle dorsolateral margin with 3 robust setae. Uropod 2 inner ramus slightly constricted. Uropod 3 rami lanceolate; without plumose setae; outer ramus 1-articulate. Telson moderately cleft (about 36%).

Female (sexually dimorphic characters). Antenna 1 flagellum without callynophore. Mandible palp article 2 without posterodistal seta.

Habitat. Bamarooka tropicalis has been found with algae, seagrasses, sediments, ascidians, bryozoans and hydroids, but most commonly among corals and coral rubble in 3–40 m depth.

Remarks. Bamarooka tropicalis is a widespread species in tropical Australia. It is currently the only species of Bamarooka known from the GBR. It can be separated from other GBR lysianassoids by its elongate head. Bamarooka anomala and B. tropicalis are the only species in the genus with elongate, reniform eyes. They are easily distinguished from each other by their fifth pereopods, which have a linear basis in B. anomala and an expanded basis in B. tropicalis .

The shape of pereopod 7 basis is slightly variable within the species. In populations from the North West Shelf the posteroventral margin is almost always rounded; in east coast populations it varies from rounded to almost straight (as in illustrated specimen).

Distribution. Australia. Queensland: Northwest Islet, Hammond Island and Goodes Island, Torres Strait (current study); Lizard Island ( Lowry & Stoddart 2002, current study). Western Australia: North West Shelf ( Lowry & Stoddart 2002). Northern Territory: Darwin, New Year Island, McCluer Island ( Lowry & Stoddart 2002).

Figures

FIGURE 1. Bamarooka tropicalis Lowry & Stoddart, 2002, male, 4.0 mm, AM P78940, north-east of North Point, Lizard Island, Great Barrier Reef.

FIGURE 2. Bamarooka tropicalis Lowry & Stoddart, 2002, male, 4.0 mm, AM P78940, north-east of North Point, Lizard Island, Great Barrier Reef.