Polysyncraton meandratum Monniot, 1993

Kott, Patricia, 2007, New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (part 4), Journal of Natural History 41 (17 - 20), pp. 1163-1211 : 1172-1173

Polysyncraton meandratum Monniot, 1993

( Figure 7B )

Polysyncraton meandratum Monniot 1993, p 6 ; Kott 2001, p 111 and synonymy.

Distribution

Previously recorded (see Kott 2001): Queensland (Caloundra, Capricorn Group); New Caledonia. New records: Queensland (Great Barrier Reef: 17.855 ° S, 146.585 ° E, 43 m, QM G308849 ; 17.605 ° S, 146.355 ° E, 39 m; 17.645 ° S, 146.375 ° E, 27 m, QM G308850 ) .

Description

The colony surface is quilted, the common cloacal canals being deep with the surface depressed over them. A superficial layer of bladder cells overlies a layer of spicules, which is interrupted only over the circular common cloacal canals. Spicules are also present around the zooids but are sparse elsewhere. Black spherical pigment cells are in the basal test. The robust zooids have a long retractor muscle from halfway down the oesophageal neck, the branchial siphon half the length of the thorax and four rows of about 10 stigmata per half row are in the oesophageal buds as well as in the adult pharynx. One colony (QM G308849) is very squashed but the spicules are seen to be similar in form, size and distribution to those previously described for this species.

Remarks

The newly recorded material is as previously described for this species, although the long branchial siphon is reported here for the first time.

Figures

Figure 7. Scanning electron micrographs. (A) Polysyncraton magnetae (QM G308818); (B) Polysyncraton meandratum (QM G308849); (C) Polysyncraton otuetue (QM G308851); (D) Polysyncraton reticulum (QM G323330); (E) Polysyncraton scorteum (QM G323343); (F) Didemnum abradatum (QM G308870); (G) Didemnum astrum (QM G308857); (H) Didemnum candidum (QM G308765).