Tenellia perca (Marcus, 1958)
|Maximum size: 15 mm.
The body and cerata of this species are translucent white with opaque
white and olive
flecks. The finger-shaped, dorso-lateral cerata are arranged in 6-10
transverse rows and, in adult
animals, can be unusually elongate. The digestive gland ranges from
olive green to brown to
black and is visible through the cerata. In Hawaiian specimens, the
have two subapical white bands rather than one. The rhinophores are
smooth and there is dark pigment on the head in
front of them.
Thought to be
introduced, Tenellia perca has
been found in fouling communities on
floating docks and thermal pollution tables at Coconut Island in
Kaneohe Bay, Oahu. In Hawaii, it is known to feed on the sea anemone, Aiptaisia sp. (Terry
Gosliner, pers. com.) (Note 1)
Oahu: Tenellia perca is native
to the Caribbean from Florida to Brazil but is now also found in
California, New Zealand, Ghana, West Africa and the Mediterranean.
It was first recorded in Hawaii from Kaneohe Bay, Oahu by Terry Gosliner in
Oct. 1972 and is listed in Gosliner, 1980 and Kay, 1979 as Cuthona perca.
Gosliner: Kaneohe Bay, Oahu; Oct. 1972.
Observations and comments:
1: The Aiptasia referred to was probably Aiptasia diaphana, now Exaiptasia diaphana.