Catriona venusta (Baba, 1949)

Catriona venusta

No field photograph submitted for this species yet

Description

A small Aeolidacea, body length 4-10 mm. The rhinophores are simple (no rings, no lamellae) — a key diagnostic feature. Cerata in 6-7 oblique rows per side: 1st row 1, 2nd 2, 3rd-4th 3 each, 5th onward 1-2 each. Right (and left) liver branches into 3 oblique rows. The genital orifice opens directly below the 2nd row on the right side; the anus opens just before the inner end of the 4th row. Anterior foot corners rounded. Ground colour orange-yellow; the cerata have a red-purple central vein and yellow tips. The masticatory edge of the jaw plate bears a single row of 12-15 denticles. Radula formula 55-60×0.1.0. The central tooth has a recessed median cusp flanked by 4-6 denticles on each side.

Distribution

Type locality is off Nishi-no-saki, Sagami Bay (500 m offshore, 10 m depth, January 1941, 1 specimen) and Hayama-Samejima, Sagami Bay (intertidal, April 1941, 4 specimens), 5 specimens total. The original description (Baba, 1949) records the species only from Sagami Bay.

Etymology

The specific epithet venusta is Latin for beautiful or graceful. The original description does not give an explicit etymology paragraph; the descriptive sense reflects the brilliant orange-yellow ground with red-purple central veins. The Japanese name "Hanazono-mino-umiushi" (flower-garden aeolid) likewise refers to the beautiful coloration.

Remarks

Originally described as Cratena venusta and later transferred to Catriona. Distinguished from the conspecifically described Cratena anulata and Cratena pinnifera by the simple rhinophores (no rings, no lamellae) and by the orange-yellow ground with red-purple central veins.