Staurotheca sp.

Cantero, A. L. Peña & Vervoort, W., 2003, Species of Staurotheca Allman, 1888 (Cnidaria: Hydrozoa: Sertulariidae) from US Antarctic expeditions, with the description of three new species, Journal of Natural History 37 (22), pp. 2653-2722 : 2712

Staurotheca sp.

(figure 20)

Material examined. 12/1002, one fragment ca 47 mm long, with male gonothecae ( USNM 1003296).

Description. General colony structure unknown due to the scarcity of material available. Hydrothecae arranged in decussate verticils of four hydrothecae (figure 20A), forming eight longitudinal rows. Hydrothecae (figure 20A–E) sunken into branch for approximately two-thirds of their volume and adnate for almost full adcauline length; sharply curving outwards at half their length. Perisarc of hydrothecae strongly developed, particularly at diaphragm. Hydrothecal aperture circular, tilted downwards, forming an acute angle with long axis of branch; rim even and frequently with renovations. Without mushroom-shaped diaphragm.

Male gonothecae present, arising at the hydrothecal base. Gonotheca fusiform (figure 20F), provided with a small distal neck, bearing a circular aperture. Distal fourth of gonothecal wall striated.

Remarks. By the absence of a mushroom-shaped diaphragm and in the shape of the hydrotheca, Staurotheca sp. is allied to S. polarsterni (cf. table 6). However, the scarcity of available material, which makes it impossible to evaluate the shape of the colony and the pattern of branching, prevents us from referring this material to any of the known species.

Ecology and distribution. The material of Staurotheca sp. was collected at a depth of 265 m off Elephant Island ( South Shetland Islands) .