Phylladiorhynchus cf. pusillus ( Henderson, 1885 )

Ahyong, Shane T., 2007, Decapod Crustacea collected by the NORFANZ Expedition: Galatheidae and Polychelidae, Zootaxa 1593, pp. 1-54 : 42

Phylladiorhynchus cf. pusillus ( Henderson, 1885)

( Fig. 20 B, 22)

Galathea pusilla Henderson, 1885: 407 [type locality: off New South Wales, Australia]; 1888: 121, pl. 12: figs. 1, 1a, b. Galathea integra Benedict, 1902: 248 [type locality: off Honshu, Japan].

Galathea lenzi Rathbun, 1907: 49 , pl. 3: fig 1 [type locality: Corral, Chile].

Phylladiorhynchus pusillus .— Haig, 1973: 282.— Baba 1974: 381; 1991: 486–487, fig. 4e, f; 2005: 305 [synonymy].

Material examined. Norfolk Ridge: NIWA 28065, 1 female (8.7 mm), southern Norfolk Ridge, 33°23.41’S, 170°11.58’E, 469–526 m, TAN0308/126 #87, 31 May 2003.

Southeastern Australia: AM P17563, 2 males (4.9–5.5 mm), 1 female (4.7 mm), S and SW of Mount Cann, Gippsland, Victoria, Australia, 120–183 m; AM E6158, 1 male (6.9 mm), S of Cape Everard, Victoria, Australia, with rhizocephalan.

Colour in life. Carapace and abdomen transparent, pale yellow-orange; with orange-red marginal spines and rostrum. Chelipeds clear, diffuse pink-red; spines orange-red. Fingers crossed by white band. Walking legs with diffuse, clear orange-red banding.

Remarks. The single NORFANZ specimen agrees with several ‘large’ Australian and New Zealand specimens reported as P. pusillus by Haig (1973) and Baba (1991), respectively, in their straight or almost straight rather than distinctly convex rostral margins. Phylladiorhynchus pusillus sensu stricto bears convex rostral margins ( Baba 1991) and generally does not exceed about 5 mm carapace length. The rostral condition of these ‘aberrant’ specimens appears not to be an allometric artefact, being stable across a wide size range ( Fig. 22 ). As presently understood, P. p u s i l l u s could be a composite taxon, so present specimens are only tentatively identified pending a review of Phylladiorhynchus by K. Schnabel (NIWA).

Distribution. Western Indian Ocean to eastern Australia, New Zealand, the Chesterfield Islands, to Japan, San Félix, and the Juan Fernández Islands; intertidal to 580 m ( Baba 2005).

Figures

FIGURE 22. Phylladiorhynchus cf pusillus (Henderson, 1885). A – J, female, 8.7 mm, TAN 0308 / 126 (NIWA 28065). K – M, female 4.7 mm, male 4.9 mm, male 5.5 mm, off Victoria, Australia (AM P 17563). N, male 6.9 mm, off Victoria, Australia (AM E 6158). A, dorsal. B, left antennule, ventral view. C, left antenna, ventral view. D, right third maxilliped, lateral view. E, third and fourth sternites. F, telson. G, right cheliped, lateral view. H – J, right pereopods 2 – 4. Scale: A, G – J = 1.0 mm; B – F = 0.5 mm; K – N = 0.7 mm.

FIGURE 20. A, Paramunida labis Macpherson, 1996, ovigerous female, 7.9 mm, TAN 0308 / 025 (NIWA 28075). B, Phylladiorhynchus cf. pusillus (Henderson, 1885), female, 8.7 mm, TAN 0308 / 126 (NIWA 28065).