Ecteinascidia Herdman, 1880

Monniot, Françoise & Monniot, Claude, 2001, Ascidians from the tropical western Pacific, Zoosystema 23 (2), pp. 201-383 : 301-302

Genus Ecteinascidia Herdman, 1880

Ecteinascidia bandaensis Millar, 1975 ( Figs 78 ; 125C )

Ecteinascidia bandaensis Millar, 1975: 268 , fig. 49. Type locality: Banda Sea.

Ecteinascidia jacerens – Monniot C. 1997b: 564 fig 3A-B, Mozambique and Madagascar.

MATERIAL EXAMINED. — Philippines. Bohol Sea, Camiguin Island, N side of White Island, offshore sand cay, 9°15.87’N, 124°39.32’E, 19.IV.1997 ( MNHN P2 ECT 84).

DESCRIPTION

In life this species is opaque. In this collection as in Mozambique and Madagascar, the tunic is white with a red ring around each siphon linked by a red median line ( Fig. 125C ) between them. Inside the rings the siphonal lobes appear as white spots. This species has been briefly described by Millar (1975) and Monniot C. (1997b). Some further details are given here. The musculature is oblique ( Fig. 78A, B ). There are about 20 oral tentacles along a wavy crest and some very small ones irregularly distributed. The prepharyngeal band is circular, made of two unequal blades, the posterior one higher. The dorsal tubercle is urn-shaped, opening by a round hole hidden in a fold of the anterior blade of the prepharyngeal band. The posterior blade of the band makes a short papilla.

The dorsal lamina is made of sharp languets, independent of each other right from their base. The branchial sac has 16 rows of stigmata and about 23 longitudinal vessels per side. The branchial meshes are elongated, with an average of two stigmata each.

The stomach is globular and asymmetrical, linked to the intestine by a protruding ring. The intestine begins with four well-pronounced caeca. The bilobed anus has the shape of pursued lips with a large slit. The massive gonads occupy all the space between the two limbs of the gut. The ovary, poorly developed in these specimens, is encircled by numerous testis follicles, which may spill onto the internal and external sides of the gut ( Fig. 78C, D ).

The sperm duct opens by a papilla against the anus, and the oviduct runs to its right side. We have not found larvae.

This species has been confused with E. jacerens Tokioka, 1954 , which has an oblique musculature but one that makes a plexus between the siphons.

Figures

FIG. 78. — Ecteinascidia bandaensis Millar, 1975; A, B, left and right sides of a zooid; C, D, left and right sides of the gut loop. Scale bar: 1 mm.

FIG. 125. — A, Perophora modificata Kott, 1985; B, Perophora namei Hartmeyer & Michaelsen, 1928; C, Ecteinascidia bandaensis Millar, 1975; D, Ascidia gemmata Sluiter, 1895 s.l.; E, Ascidia ornata n. sp.; F, Ascidia sydneiensis Stimpson, 1855.