Tanystylum haswelli Child, 1990

Arango, Claudia P., 2003, Sea spiders (Pycnogonida, Arthropoda) from the Great Barrier Reef, Australia: new species, new records and ecological annotations, Journal of Natural History 37 (22), pp. 2723-2772 : 2733-2734

Tanystylum haswelli Child, 1990

Tanystylum haswelli Child, 1990: 317–319 , figure 2; Stock, 1994: 37–38, figure 12.

Material examined. Turtle Bay, in Cladophora prolifera , 27 March 1997, two X, one W. Holmes Reef, 18 m, collected by scuba amongst the coralline alga Amphiroa sp. , sponges and hydroids, 18 September 1998, one W (coll. Diaz-Pulido).

Description. Trunk length 0.62 mm, width 0.54 mm, not segmented, granulate surface; body circular-shaped, crurigers wide, crowded, with small distal tubercle; ocular tubercle pointing forward; abdomen horizontal, tip curved; proboscis slightly tapering distally. Small buds as chelifores. Palps four-segmented, second segment the longest. Ovigers 10-segmented, first and second segments wider. Legs short, tibiae subequal, long distal spiny spur on first coxa, dorsal nodes covered by short spines on tibiae; cement gland a short dorsal duct; propodus robust, curved, without heel, three heel spines, double row of sole spines; claw half the length of the propodus, auxiliaries longer than half the length of the main claw.

Distribution. This is the second Australian record of the species, originally described from a male collected from Lizard Island, northern GBR (Child, 1990). The female and juveniles were described from material collected around Papua New Guinea (Stock, 1994).

Remarks. Tanystylum haswelli has some similarities with T. hooperi Clark, 1977 from New South Wales in the general appearance of proboscis, legs and abdomen, but the males of T. hooperi have an apophysis on the seventh segment of the ovigers. It is also similar to T. bredini Child, 1970 from the Indo-west Pacific, sharing the lack of apophysis on ovigers, four-segmented palps and shape of ocular tubercle but differs in a more tapering proboscis, two anterior and posterior tubercles on crurigers and shorter terminal palp segment in T. bredini .