Pycnoclavella detorta

Pycnoclavella detorta (Sluiter, 1904) Podoclavella detorta Sluiter, 1904: 6; not Kott, 1957b: 130. Clavelina detorta: Van Name, 1918: 133; Millar, 1975: 209; Monniot, F., 1988: 202; Monniot and Monniot, 2001: 231. Pycnoclavella detorta: Kott, 1990a: 71. Distribution. New records: Queensland (Swain Reefs, QM G305809). The new record confirms that the species is a common component of the West Pacific ascidian fauna (see Kott, 1990a). Larvae are present in the newly recorded specimens (collected in July). Remarks. Podoclavella detorta: Kott, 1957b (BM 1956. 5.2.19) has been re-examined. The specimens are long, narrow, horny stems up to 5 cm long, containing the long oesophageal neck and the slightly expanded distal part of the abdomen. They are joined to one another at their base by short stolons. However, the thoraces have disintegrated, and it was not possible to confirm Kott’s (1957b) description. Apart from the reported four rows of stigmata and longer and horny stalks, these specimens are like P. detorta. At this stage the significance of the reported differences is not known. Clavelina auracea Monniot, 1997a is also similar to P. detorta, except for ferilization of the eggs in a brood pouch at the postero-dorsal corner of the abdomen, five (rather than six) rows of stigmata, and the larvae. Although they lack the usual frontal plate of Clavelina larvae, the larval adhesive organs are not inverted tubes as in Pycnoclavellidae. Monniot (1997a) has not described the cerebral vesicle and it is not clear if an otolith is present or not. The affinities of this species are problematical, although the fertilization of eggs at the posterior end of the thorax suggests that it is closer to Clavelina than to Pycnoclavella.
Published as part of KOTT, PATRICIA, 2003, New syntheses and new species in the Australian Ascidiacea, pp. 1611-1653 in Journal of Natural History 37 (13) on page 1617, DOI: 10.1080/00222930110104258, http://zenodo.org/record/5260089