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. 4 e, 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).