Utelga heinckei ( Attems, 1897 ) Karling, 1954

Reygel, Patrick C., Willems, Wim R. & Artois, Tom J., 2011, Koinocystididae and Gnathorhynchidae (Platyhelminthes: Rhabdocoela: Kalyptorhynchia) from the Galapagos, with the description of three new species, Zootaxa 3096, pp. 27-40 : 39

Utelga heinckei ( Attems, 1897) Karling, 1954

Locality. Santa Cruz Island, Station IX6 b, rock pools.

Known distribution. North Atlantic: West Coast of USA, North Sea, Skagerrak, Irish Sea, Irish Atlantic coast (see Karling 1980 and references therein; Willems et al. 2007).

Material. One individual studied alive, one sagittally-sectioned specimen ( ZMUG 23322).

Remarks. The internal structure is in accordance with the observations and remarks by Karling (1954, 1980). The epidermis is clearly cellular, as was mentioned by Karling (1954). One of the hooks associated with the copulatory organ is 40 µm long, slightly larger than the other two (35 µm). These two smaller hooks also differ slightly in shape from the third, larger hook. Their basal plate is smaller and the gutter-shape of the spine-like part is less prominent. Although the measurements are slightly larger, they correspond well with earlier data (e.g. Karling 1954: 22.5−28 µm; Karling 1980: 22−35 µm; Willems et al. 2007: 10−23 µm). Difficulties with interpretation of shape and size of the hooks are mentioned by Willems et al. (2007).