Macrophthalmus, DESMAREST, 1823

Martin, Joel W. & Haney, Todd A., 2005, Decapod crustaceans from hydrothermal vents and cold seeps: a review through 2005, Zoological Journal of the Linnean Society 145 (4), pp. 445-522 : 496

GENUS MACROPHTHALMUS DESMAREST, 1823 MACROPHTHALMUS HIRTIPES ( HELLER, 1862)

Type locality: South Pacific Ocean, New Zealand, Auckland Harbour (from McLay, 1988) .

Known range: Endemic to New Zealand: North, South and Stewart Islands, and possibly Campbell Island ( McLay, 1988: 336).

Occurrence at vents or seeps: Whale Island, New Zealand.

Remarks: Specimens of this species were collected by Russian divers at relatively shallow (30–40 m) hydrothermal seeps off Whale Island, a volcanic island at the southern end of the Kermadec Arc ( R. Webber, pers. comm.; see also Kamenev et al., 1993; Clark & O’Shea, 2001). The species is a New Zealand endemic that is normally found in the lower intertidal zone to a depth of only 13 m (although records from the stomach of a snapper may indicate depths to 40 m or more; R. Webber, pers. comm.; and see McLay, 1988). It is almost certainly a vagrant at this hydrothermal site. The species is known to burrow deeply into black (presumably anoxic) sediments, and so it may to some degree be pre-adapted for taking advantage of an environment rich in sulphide-eating bacteria. Kamenev et al. (1993) reported it at a range of temperatures (17–81°C) within a ‘volcanic depression’ near Whale Island, suggesting the species is fairly heat-tolerant.

Crabs collected at deeper sites (to 42 m) were taken with a 0.25-m 2 grab device; when collected they buried themselves in the sediment within the grab, which under normal circumstances would be a logical escape response but which, because of the hydrothermally heated sands off Whale Island, resulted in their death by cooking ( R. Webber, pers. comm.).