Acryptolaria gracilis ( Allman, 1888 )

Watson, Jeanette E., 2018, Some Hydroids (Cnidaria, Hydrozoa) from the Great Australian Bight in the collection of the South Australian Museum, Zootaxa 4410 (1), pp. 1-34 : 2-3

Acryptolaria gracilis ( Allman, 1888)

Figure 1A

Cryptolaria gracilis Allman, 1888: 42 , pl. 20, figs 2, 2a.— Farquhar, 1896: 461.— Hutton, 1904: 320. Acryptolaria gracilis .— Totton, 1930: 162.— Ralph, 1958: 314, fig. 3b–d. — Watson & Vervoort, 2001: 157, fig. 4a–c.— Vervoort & Watson, 2003: 46, fig. 6D, E.— Bouillon et al, 2006: 338.

Material examined. SAM H2321, preserved colony and one microslide ( SAM H2566). Cascade Seamount, Tasman Sea, (43.96° S, 150.48° E), 297 km off Southeast Cape, Tasmania, trawl, 760–910 m, coll: R. Southcott, 10/11/1990 .

Remarks. Branches of a single colony or an entire colony 65 mm high. Colour (preserved material), pale yellowish green.

The material is identical with descriptions of Acryptolaria gracilis by Watson & Vervoort (2001) and Vervoort & Watson (2003).

Branching is more or less planar, the branches fascicled to the tip of colony. The annular rings on the hydrothecae were assumed to be overgrowth by cauline polysiphonic tubes by Watson & Vervoort (2001). Their fig. 4c however, shows a few distal rings on the hydrotheca distinct from the fasciculations. The present material clearly shows that the annular rings are not due to polysiphonic tubes but are bodily thickenings of the hydrotheca. Distribution. New Zealand, Great Australian Bight, Cascade Seamount.