Pyura irregularis ( Herdman, 1882 )

Monniot, Francoise, 2021, New records of deep-sea ascidians (Tunicata, Ascidiacea) from the New Caledonia region, Zootaxa 4996 (3), pp. 443-468 : 457-458

Pyura irregularis ( Herdman, 1882)

Figure 14

Station: Kanacono CP 4739. One specimen.

Pyura irregularis: Kott 1985 and synonymy; Monniot F. & Monniot C. 2003. The tunic is brown and corrugated ( Fig. 14C ). The siphons are distant of one third of the body width. The body wall is thick with a dense musculature. The oral tentacles have only short and spaced first-order ramifications of ( Fig. 14D ). The long U-shaped dorsal tubercle is included in a particularly deep V of the prebranchial band ( Fig. 14D ). The dorsal lamina has numerous pointed languets. The branchial sac has nine entire branchial folds on each side and an incomplete fold close to the endostyle ( Fig. 14A ). In a specimen 4cm in length the formula on the right side is: E – 3 (4) 3 (11) 6 (19) 8 (22) 8 (30) 8 (34) 6 (32) 6 (32) 5 (25) 4 (16) 1 – DL

There are three–five stigmata per mesh between the folds and parastigmatic vessels are present. The gut loop is particularly large ( Fig. 14B ). The hepatic gland is in two voluminous cauliflower-shaped masses. The anus has eight lobes. There is one long ramified gonad on each side: the oviduct and sperm duct open in joined papillae. Large endocarps cover the gonad lobes, some are present on the right body wall, and numerous endocarps protrude along the entire intestine. There is a narrow atrial velum.

All characters well correspond to Kott’s (1985) specimens and to the specimens already collected from New Caledonia (Monniot F. & Monniot C. 2003, Fig. 42).

Figures

FIGURE 14. Pyura irregularis. A, branchial tissue; B, body ventrally opened; C, one specimen; D, oral tentacles and dorsal tubercle. Scale bars = 1cm.