Aplidium multiplicatum Sluiter, 1909

KOTT, PATRICIA, 2003, New syntheses and new species in the Australian Ascidiacea, Journal of Natural History 37 (13), pp. 1611-1653 : 1629-1630

Aplidium multiplicatum Sluiter, 1909

Aplidium multiplicatum Sluiter, 1909: 101 ; Kott, 1992a: 567 and synonymy.

Aplidium controversum Monniot and Monniot, 1996: 135 ; 2001: 207.

Distribution. New records: Queensland (Swain Reefs, QM G308426, G308422, G308425). This commonly encountered species has a wide range in the western Pacific from Hong Kong, the Philippines, Kiribati, Majura Atoll, Truk, Ponape and the Palau Is to Darwin and around the Australian coast. Although Kott (1992a: 567) states that it does not occur across the southern coast of the continent the species has been reported in St Vincent Gulf and off the Yorke Peninsula in South Australia.

Description. The colonies have the characteristic colourless translucent test with soft vermilion zooids with a yellow thorax along each side of branching common cloacal canals with common cloacal apertures at junctions of the canals and opaque white granular material in the soft test that surrounds each zooid. Some Prochloron is on the surface. Larvae, in the newly recorded colonies, have a circle of lateral vesicles around the anterior half of the trunk. The three antero-median adhesive organs are very shallow (see Kott, 1992a).

Remarks. Monniot, F. (1987), following Tokioka (1953, 1967) and Kott (1963) thought specimens from New Caledonia were synonymous with the eastern Pacific A. californicum (Ritter and Forsyth, 1917) . Kott (1992a) assigned western Pacific and Australian specimens to A. multiplicatum Sluiter, 1900a , and included A. californicum: Monniot, F., 1987 from French Polynesia (but not the eastern Pacific species) as a synonym. Monniot and Monniot (1996) rejected that synonymy because the specimens require re-examination and erected a new species, A. controversum Monniot and Monniot, 1996 , a wide-ranging western Pacific species (from New Caledonia, Palau Is and Australia) distinguished from A. multiplicatum by the presence of two rows of testis follicles in the posterior abdomen. However, testis follicles of the more than 60 specimens that Kott (1992a) examined, often are bunched, but are spread out in two rows in relaxed zooids and the degree of contraction affects the extent to which they are bunched (see Millar, 1975; Kott, 1992a). Valid grounds to separate these species are not available. Characteristic of the species, to which all authors refer, is the soft, translucent test and the rows of zooids. Of the synonyms of A. multiplicatum set out in Kott (1992a), the material described by Tokioka (1967), Van Name (1918), Nishikawa (1984) and A. californicum: Monniot, F., 1987 is consistent both in geographic range and morphology with the present species (see Kott, 1992a).

In the detailed discussion of the synonymy of A. multiplicatum, Kott (1992a) specifies its difference from A. californicum , a distinct eastern Pacific species. The redescription of specimens of A. californicum from British Columbia (Monniot and Monniot, 1996) establishes that these specimens are an Aplidium species , but does not establish a distinction between A. californicum and A. multiplicatum (except for fewer stomach folds). This redescription is irrelevant to the establishment of A. controversum as a species distinct from A. multiplicatum .