Pyura vittata ( Stimpson, 1852 )

Monniot, Françoise, 2009, Some ascidians from Indonesian marine lakes (Raja Ampat Islands, West Papua), Zootaxa 2106, pp. 13-40 : 37-38

Pyura vittata ( Stimpson, 1852)

( Figures 18 B, 20)

Cynthia vittata Stimpson, 1852: 230

Pyura vittata: Monniot F. & Monniot C. 2008 and synonymy.

Material. Indonesia. West Papua, Gam Island, Danau Ctenophore marine lake, 00°27.289’S – 130°29.580’E, 10.5m, 26/XI/2007, coll;L.J. Bell and L.E. Martin, DCG 0 0 4 ( MNHN S2 PYU 428); West Papua, Gam Island, Danau A Gam marine lake, 00°26.518’S – 130°41.134’E, 0.5m, 26/XI/2007, coll. L.J. Bell and L.E Martin, DAG 0 57 ( MNHN S2 PYU 429).

Description. Agglomerated or isolated, the specimens about 20mm in length are covered with epibionts and some sedimentary particles ( Fig. 18 B). The siphons are retracted when fixed and show iridescent spinules. The upper part of the body is corrugated around the apertures, smoother ventrally. Out of the tunic, the body wall is thin with strong muscles in sphincters around the siphons and radiating muscular bundles extend from them on a half dorsal part of the body. The tentacles have one order of ramifications. About 15 longitudinal vessels are on the 6 branchial folds ( Fig. 20 A), and 3 to 5 between the folds. At the oesophageal entrance each vessel ends in a long papilla. The first intestinal loop is long, the second is variable but always curved ( Fig. 20 B). Endocarps are present along the whole external side of the intestine. The hepatic gland consists of several lobes of dense diverticula on the thin elongated stomach. The gonads ( Fig. 20 B) of the typical pyurid shape, have endocarps on their lobes. Both oviducts and sperm ducts are long and open close to each other with the anus at the cloacal aperture. The body wall is devoid of endocarps.

The needle-shaped spinules 0.15mm long are very dense ( Fig. 20 D). In light microscopy ( Fig. 20 C) a small bulb appears in transparency at their attachment in an extended part of the siphonal lining, which cannot be seen in electron microscopy.

This widely distributed species was previously collected in marine lakes from Palau ( Monniot F. & C. 2008).

Figures

FIGURE 20. Pyura vittata: A, branchial sac; B, body opened along the ventral line; C, D spinules of the siphonal lining: C, in light microscopy on flattened tissue; D, with SEM, scale bar = 100 µm.

FIGURE 18. A, Pyura elongata. B, Pyura vittata.