Didemnum moseleyi ( Herdman, 1886 )

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 : 2448-2450

Didemnum moseleyi ( Herdman, 1886)

( Figures 9A , 16C , 20G )

Leptoclinum moseleyi Herdman 1886, p 272 .

Didemnum moseleyi: Kott 2001, p 211 and synonymy; 2004a, p 753; 2004c, p 40.

Distribution

Previously recorded (see Kott 2001, 2004a): Western Australia (off Port Hedland); Queensland (Currumbin to Capricorn Group, Mackay); Indonesia; Philippines; Palau Is; Tokara Is; New Caledonia; Indian Ocean. New records: Western Australia (W of Pt Cloates, WAM 175.93; Cockburn Sound, WAM 310.89); Northern Territory (Bynoe Harbour, QM G308713).

Description

Newly recorded colonies are of the usual sheet-like encrusting form with crowded spicules of the usual diverse forms, horizontal common cloacal cavities and small zooids with seven coils of the vas deferens. Larvae are present in the colony from Bynoe Harbour collected in May and are described for the first time. The trunk is 0.55 mm long, the tail is wound almost the whole way around it and there are six finger-like lateral ampullae, each with a terminal cap of columnar cells along each side of the three antero-median adhesive organs. Remarks

This widely occurring tropical species has been recorded only once before from Western Australia; and Cockburn Sound is the most southerly record for it.

Figures

Figure 9. (A) Didemnum moseleyi (QM G308713): larva. (B, C) Didemnum plebeium sp. nov. (WAM 155.93, holotype): (B) thorax; (C) larva. Scale bars: 0.1 mm.

Figure 16. Scanning electron micrographs of the calcareous spicules of: (A) Didemnum incanum (SAM E3238); (B) Didemnum leopardus sp. nov. (QM G308719, holotype); (C) Didemnum moseleyi (WAM 175.93); (D) Didemnum plebeium sp. nov. (WAM 155.93, syntypes); (E) Didemnum stragulum (WAM 162.93); (F) Didemnum ternerratum (SAM E3240); (G) Trididemnum amiculum (SAM E3263); (H) Trididemnum areolatum (QM G308746).

Figure 20. In situ images of: (A) Didemnum fragum (SAM E3266); (B) Didemnum fuscum (QM G308730); (C) Didemnum incanum (SAM E3252); (D) Didemnum jucundum (SAM E3236); (E) Didemnum leopardus (QM G308719, holotype); (F) Didemnum microthoracicum (SAM E3256); (G) Didemnum moseleyi (QM G308713); (H) Didemnum pellucidum (SAM E3271).