Anchistioides willeyi ( Borradaile, 1899 )

Bruce, A. J., 2008, Palaemonoid shrimps from the Australian north west shelf, Zootaxa 1815, pp. 1-24 : 2-3

Anchistioides willeyi ( Borradaile, 1899)

( Fig. 1)

Palaemonopsis willeyi Borradaile, 1899 ,: 410, pls. 36, 37, fig. 7.

Amphipalaemon willeyi – Borradaile, 1917,: 407, pl. 59, fig. 13.

Amphipalaemon willeyi – Gordon, 1935,: 435, figs. 23a, 24a. – Holthuis, 1952,: 18, 214–219, figs. 106, 107. – Bruce, 1991b: 269–272, figs 3g, 29, 30. – Davie, 2002: 221. – Bruce, 2008: (in press).

Material examined. (i) 1 ♀♀, CL, 6.1, 1 juv. ♀, CL 3.5, CMAR Cruise SS05 2007, stn 172, 124.011°S; 13.4565°E, 105m, beam trawl; 16 May 2007, QM W 28399. (ii) 1 ovig . ♀, CL 15.0, idem, QM W 28400.. (iii) 2 ♂, CLs 8.5, 8.0, CMAR Cruise SS 05/2007 082, Imperieuse L 23 transect, 18°27’37”S, 120°08’41”E, 80m, Sherman sled 19 June-2007, NMV J56064 . (iv) 1 ♀, CL 7.5, CMAR Cruise SS 2005/10, stn 170, off Barrow

Island, 20°59’05”S 114°54’25”E to 20°59”40”S 11°54’32”E, 101– 100m, beam trawl, 13 December 2005, coll. G.C. Poore, NMV J54476 .

Diagnosis. A species of Anchistioides lacking a long edentate rostral tip, generally with blunt postorbital tubercles and the second pereiopod fingers as long as or longer than palm length.

Colouration. Highly transparent, with deeply pigmented corneae.

Remarks. The two specimens (i) are complete, the larger ( Fig. 1A) with a rostral dentition of 9/3, the smaller with 10/3. In both the postorbital tubercles are blunt and the rostrum without a long edentate tip. In the larger female the rostrum is 0.8 of the CL with a deeper lamina and in the smaller female, 1.1 times with a shallower lamina. Specimen (ii) ( Fig. 1A) is unusually large, with a vast number of eyed ova, length about 0.85 mm. The rostrum is 0.75 of the CL with a deep lamina and a dentition of 10/6, without a long edentate tip, with the ventral spines slightly abnormal ( Fig. 1B). The postorbital tubercles ( Fig. 1C) are strongly acute and the second pereiopod fingers are longer than the palm on the right side and shorter on the left. The proportions of second pereiopod fingers to palm is variable from 1.05 and 1.25 in the smallest specimen, 0.97 and 1.08, to 0.86 and 1.17 in the largest. The second pereiopod chelae are subequal, about 1.15 of the CL. The occurrence of two forms of second pereiopod chela, with long fingered and short fingered types, in A. willeyi was first noted by Bruce (1976b; 1978). The present specimens indicate that this distinction is not always clear cut. Specimens (iii) both have a rostral dentition of 9/4 with second pereiopod chelae with fingers subequal to palm length or very slightly greater, the postorbital tubercles blunt and the rostra about 0.8 of the CL. Specimen (iv) has a rostral dentition of 8/4, also with the fingers of the second pereiopod subequal to the chela length.

Distribution. Previously reported in Australian waters from Western Australia; Bluff Point, Enderby Island, Dampier Archipelago (Bruce, in press); Northern Territory: Darwin Harbour ( Bruce, 1988), and Queensland: Capricorn Islands; Moreton Bay ( Bruce, 1983). Otherwise known from Kenya, Zanzibar, Tanganyika, Madagascar, Maldive Islands, Singapore, Borneo, Indonesia, South China Sea, Philippines, New Caledonia and Chesterfield Islands.