Polysyncraton cuculliferum ( Sluiter, 1909 )

Kott, Patricia, 2005, New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (Part 3), Journal of Natural History 39 (26), pp. 2409-2479 : 2427-2428

Polysyncraton cuculliferum ( Sluiter, 1909)

( Figures 4A , 18G )

Diplosomoides cuculliferum Sluiter 1909, p 90 .

Polysyncraton cuculliferum: Kott 2002a, p 30 and synonymy; 2004b, p 2476; 2004c, p 40.

Distribution

Previously recorded (see Kott 2002a, 2004b): Northern Territory (Darwin, Bynoe Harbour); Queensland (Great Barrier Reef); Indonesia. New record: Northern Territory (Bynoe Harbour, QM G308715).

Description

The newly recorded colonies, spicules, zooids, and larvae are as previously described. The specimen differs from others in the distribution of spicules which do not form an opaque layer at the surface, although the branchial lobes, like six-petalled daisies, protrude from the surface of the colony, one petal usually being larger than the others. Also, spicules are present in the basal and the central test mass with some mud and other debris. Clumps of zooids are suspended in the extensive common cloacal cavity in test ligaments connecting the surface with the basal or central test. Larvae are found to have particularly large external horizontal ampullae on the left side and this has been confirmed in larvae previously recorded.

Remarks

The surface of the colony, with the spicule-filled lobes protruding from the surface, resembles the surface of some colonies of Didemnum cygnuus Kott, 2001 and Polysyncraton papyrus Kott, 2001 (see below). The common cloacal cavities are better developed in the newly recorded colony than has been reported previously. The appearance of the living colony, including its greenish colour, is identical with that shown by Kott (2001, Plate 5B) as is the colony from South Shell I., Darwin (QM G308604: Kott 2004b). Kott (2004b) is wrong in referring to the larval external horizontal ampulla on the right side of the larval trunk (it is always on the left); and the specimen from which the larva was taken is QM G308616 (not QM G308608 sic).

Figures

Figure 4. (A) Polysyncraton cuculliferum (QM G308715): larva. (B–D) Polysyncraton galaxum (SAM E3250): (B) thorax; (C) gut loop; (D) larva. Scale bars: 0.1 mm.

Figure 18. In situ images of: (A) Leptoclinides decoratus (SAM E3257); (B) Leptoclinides frustus (SAM E3255, holotype); (C) Leptoclinides imperfectus (SAM E3243); (D) Leptoclinides lissus QM G308709); (E) Leptoclinides rigidus (QM G308708); (F) Leptoclinides seminudus (SAM E3264); (G) Polysyncraton cuculliferum (QM G308715); (H) Polysyncraton galaxum (SAM E3261).