Itaipusa variodentata (Karling, Mack-Fira & Dörjes, 1972) Karling, 1978

New locality. Santa Cruz Island, stations IX5 b, IX5 d, IX6 b, rock pools.

Known distribution. Hawaii (Karling et al. 1972).

Material. Four specimens studied alive, 28 specimens serially-sectioned (ZMUG 23289-23316).

Remarks. The complex structure and orientation of the organs in the specimens studied alive are in accordance with the observations of Karling et al. (1972) on specimens from Hawaii. On sections it is clear that the epidermis is cellular, showing distinctly-delimited epidermal cells as was mentioned in the original description (Karling et al. 1972). The Galapagos specimens (3 mm long) are, however, clearly larger than those from Hawaii (Karling et al. 1972: 2 mm). The two hooks of the copulatory organ clearly differ in size in comparison with those from Hawaii. The smaller hook measures 52−108 µm (x = 86 µm; n = 4), whereas the larger one measures 75−140 µm (x = 102 µm; n = 4). This is significantly larger than what was observed by Karling et al. (1972): 30 µm for the small hook and 37 µm for the large hook. However, since no other differences could be observed and since molecular data are lacking in order to back up a splitting of the species, we deliberately choose not to describe the population from the Galapagos as a separate species for the time being.