Taxonomic revision of the marine genus Heterodrilus Pierantoni (Oligochaeta, Tubificidae).
Zoologica Scripta
10(2): 111-132.
Publication
Available for editors
Marine tubificids possessing trifid anterior setae are morphologically and taxonomically reviewed, on the basis of material from the Atlantic and Pacific Oceans. Heterodrilus Pierantoni, 1902 is revised to include thirteen species, H . arenicolus Pierantoni, 1902, H . minisetosus sp.n., H. ascensionensis sp.n., H . queenslandicus (Jamieson, 1977), H . lacertosus sp.n., H . scitus sp.n., H . keenani sp.n., H. claviatriatus sp.n., H . subtilis (Pierantoni, 1917), H . jamiesoni sp.n., H. occidentalis sp.n., H. pentcheffi sp.n., and H . bulbiporus sp.n. The genus is briefly defined: marine tubificids with trifid setae in preclitellar segments (with H . subtilis as the only exception); paired spermathecae located in segment X; vasa deferentia entering apical, ental ends of slender, ciliated atria, which bear broadly attached masses of prostate glands; paired male pores, and generally with penial setae arranged in bisetal bundles. Heterodriloides gen.n. is established for H . quadrithecatus sp.n., distinguished from Heterodrilus by two main features: its spermathecae are located in XII, with a supplementary pair generally located in XI; and its vasa enter the ectal part of the atria. Giereidrilus gen.n., a third genus with trifid setae, is established to include Phallodrilus ersei Giere, 1979 and G. inermis sp.n. Both species have unpaired spermathecal and male pores, and their atria are not ciliated. Heterodrilus, Heterodriloides and Giereidrilus are placed in the subfamily Rhyacodrilinae Hrabe, 1963.