Turbellarian taxonomic database

Abstract / Notes

Twelve new species of Polycystididae Graff, 1905 are described from the Australian east coast. Nine of them
could not be placed in any of the existing genera, and therefore six new genera are erected. Alchoides n.
gen. differs from all other polycystidid genera by the presence of a bundle of glands that opens into the
distal part of the male atrium (accessory vesicle type V). Two species are included in the genus, A.
alchoides n. sp. and A. dittmannae n. sp., which differ from each other in the shape of the stylet. Ametochus
gehrkei n. gen n. sp. can be distinguished from other polycystidids by the presence of a prostate vesicle
type III associated with a prostate stylet type III, combined with the presence of an accessory stylet type
III, while a prostate stylet type II is lacking. Typical for Arrawarria inexpectata n. gen n. sp. is the
combined presence of an armed cirrus with a prostate vesicle type II connected to a prostate stylet type II.
Two species are assigned to the new genus Duplexostylus n. gen.: D. rowei n. sp. and D. winsori n. sp. These
two species have two unique features: a prostate vesicle type IV directly connected to a prostate stylet type
III and an asymmetrical septum that surrounds the proximal part of the male atrium. They can be distinguished
from each other by differences in the detailed construction of their stylets. Two new species are placed in
the new genus Stradorhynchus n. gen.: S. caecus n. sp. and S. terminalis n. sp. They have unpaired gonads and
a prostate vesicle type IV connected to a prostate stylet type IV, which combination of characters makes them
unique within the Polycystididae. The two species differ from each other in the shape and size of the stylet.
Triaustrorhynchus armatus n. gen., n. sp. is the first species of the Polycystididae to have three types of
stylet in the male atrium: a prostate stylet type II, a prostate stylet type III and an accessory stylet type
III. Three new species could be placed in existing genera: Cincturorhynchus monaculeus n. sp.,
Paraustrorhynchus caligatus n. sp. and Polycystis australis n. sp. All three differ from their congeners in
the form and dimensions of their stylets. All newly described species are discussed, giving their
similarities and differences with resembling species. Austrorhynchus hawaiiensis Karling, 1977 is reported
for the first time in Australia, and the Australian population is compared with populations from other
regions. The presence of Gyratrix hermaphroditus Ehrenberg, 1831, one new species of Paulodora Marcus, 1948
and a new genus of Typhlopolycystidinae Evdonin, 1977 is mentioned.

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