Didemnum candidum Savigny, 1816

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 : 1177-1178

Didemnum candidum Savigny, 1816

( Figure 7H ) Didemnum candidum Savigny 1816, p 194 ; Kott 2001, p 157 and synonymy; 2004b, p 2489.

Distribution

Previously recorded (see Kott 2004b): Western Australia ( Ashmore Reef, Kimberley coast); Queensland (Great Barrier Reef); Gulf of Suez; Gulf of Arabia; West Indian Ocean. New record: Queensland (Noosa Heads, QM G308765).

Description

In life, the colony is a red sheet, with relatively small (to 0.05 mm diameter) stellate spicules crowded throughout. The spicule rays are rod-shaped, but sometimes obelisk-shaped with a blunt conical rather than rounded tip.

Remarks

Its location on the New South Wales coast is the most southerly so far recorded for this species. Its morphology is very conservative and the species is similar to Didemnum coralliforme Kott, 2004a and D. madeleinae (F. and C. Monniot, 2001) which have spicules the same size, but with more pointed rays, the former with longer rays, and the latter with short and conical rays. Didemnum delectum Kott, 2001 is temperate and has smaller spicules, but it otherwise resembles the present species.

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).