Olavius cornuatus sp.n. (Oligochaeta, Tubificidae) from Georges Bank (NW Atlantic)

Olavius cornuatus sp.n. is described from Georges Bank off Massachusetts. It is distinguished from other species of Olavius Erséus, 1984 by its curved, horn-shaped atria ending in large, protrusible penes and up to six ectally hooked penial setae per bundle.     

New and Little-Known Species of Deep-sea Tubificidae (Oligochaeta) from the North-West Atlantic

Eight species of Tubificidae are reported from deep-sea samples taken south of Massachusetts. Phallodrilus grasslei sp. n., with heavily muscular vasa deferentia, and penial setae, two per bundle, oriented with ectal ends obliquely pointing towards the anterior, and P. rostratus sp. n., with a long and narrow, snout-like prostomium, heavily muscular, tripartite atria, and small, hooked penial setae, about five per bundle, are described. Phallodrilus biparis Erséus, previously known only from off France in the north-east Atlantic, is reported and depicted. Taxonomic notes are provided for Adelodrilus voraginus (Cook), A. fimbriatus Erséus, Bathydrilus asymmetricus Cook, and B. atlanticus Erséus. The depth distribution of all eleven deep-sea tubificid species known to occur south of Massachusetts are briefly discussed.     

Marine Oligochaeta from the Koster Area, West Coast of Sweden, with Descriptions of Two New Enchytraeid Species

A total of 28 species of marine Oligochaeta (belonging to the families Naididae, Tubificidae and Enchytraeidae) are reported from eulittoral and sublittoral sediment samples taken in the Koster area on the Swedish West Coast. Lumbricillus algensis sp.n. and Grania ovitheca sp.n. are described and their morphological and taxonomical relations to other enchytraeids are discussed. L. algensis is characterized mainly by its spermathecae, which project into segment VI, and by its very large penial bulbs. G. ovitheca possesses no dorsal setae, the ventral setae being present posterior to the clitellum only, and its spermathecae consist of a narrow duct and a large egg-shaped to oval ampulla, filling most of the coelom of segment V. Four sublittoral species, Limnodriloides barnardi (Tubificidae), Lumbricillus semifuscus, Marionina sublitoralis and Grania roscoffensis (all Enchytraeidae) are reported as new to the Swedish fauna.     

Four new interstitial species of marine Oligochaeta representing a new family

A new oligochaete family, Randiellidae, is established for R. multitheca sp.n. (from the continental shelf off the east coast of the U.S.A.), R. litoralis sp.n. (from Oregon, U.S.A.), R. caribaea sp.n. and R. minuta sp.n. (both from Guadeloupe and Martinique), all members of a new marine genus Randiella. The species are characterized by small single-pointed and somewhat sigmoid somatic setae, slender (generally hair-like) modified genital setae in segment X, sperm funnels in X (if one pair), or in X and XI (if two pairs), very simple male ducts lacking atria, clitellum over XII-XIII, and multiple spermathecae in VII and/or VIII.     

The marine Tubificidae (Oligochaeta) of the barrier reef ecosystems at Carrie Bow Cay, Belize, and other parts of the Caribbean Sea, with descriptions of twenty-seven new species and revision of Heterodrilus, Thalassodrilides and Smithsonidrilus

Fifty-nine species of Tubifieidae are recorded from Belize on the Caribbean side of Central America. Twenty-five are new to science: Ainudrilus geminus sp.n., Heronidrilus gravidus sp.n., Heterodrilus flexuosus sp.n., H. ranus sp.n., H. modestus sp.n., Coralliodrilus rugosus sp.n., C. randyi sp.n., Phallodrilus compactus sp. n., P. singularis sp.n., P. vicinus sp.n., P. nasutus sp.n., P. bipartitus sp.n., Inanidrilus reginae sp.n., Olavius finitimus sp.n., O. vacuus sp.n., O. (Olavius) pravus sp.n., Bathydrilus vetustus sp.n., B. egenus sp.n., Thalassodrilides bruneti sp.n., Limnodriloides anxius sp.n., L. major sp.n., L. sacculus sp.n., L. adversus sp.n., Smithsonidrilus appositus sp.n., S. involutus sp.n. Phylogenetic analyses indicate that Heterodrilus Pierantoni, 1902, Thalassodrilides Brinkhurst & Baker, 1979, and Marcusaedrilus Righi & Kanner, 1979, are paraphyletic taxa as previously defined. They are therefore revised to include also apomorphic species earlier attributed to separate genera; in so doing, Marcusaedrilus becomes a junior synonym of Smithsonidrilus Brinkhurst, 1966. Smithsonidrilus pauper sp.n. (Peru), and S. multiglandularis sp.n. (Florida and Puerto Rico) are also described, and Limnodriloides claviger Erséus, 1982 is regarded as a synonym of L. pierantonii (Hrabě, 1971).     

Taxonomic Revision of the Marine Genus Heterodrilus Pierantoni (Oligochaeta,Tubificidae)1

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 Hrabě, 1963.     

Taxonomic Studies of Phallodrilinae (Oligochaeta, Tubificidae) from the Great Barrier Reef and the Comoro Islands with Descriptions of Ten New Species and One New Genus

A taxonomic and morphological account of a collection of Phallodrilinae from coralline sands at Heron Island in Australia's Great Barrier Reef is given. Ten new forms are described: Jamiesoniella athecata gen. et sp.n. Phallodrilus rectisetosus heronensis subsp.n. P. geniculatus sp.n. P. filithecatus sp.n. P. clavatus sp.n. (latter three all devoid of an alimentary canal), Bathydrilus superiovasatus sp.n. Coralliodrilus atriobifidus sp.n. C. oviatriatus sp.n. C. parvigenitalis sp.n. and the gutless C. avisceralis sp.n. Morphological notes are given for Phallodrilus albidus Jamieson, 1977 and Bathydrilus rohdei (Jamieson, 1977). The new meiobenthic genus Jamiesoniella is characterized by having simple atria with only one pair of prostate glands, which are attached to ectal parts of atria, and by lacking spermathecae and penial setae, The genus is probably related to Aktedrilus Knöllner and Bacescuella Hrabě. A gutless species, Phallodrilus comorensis sp.n. is described from the Comoro Islands in the Mozambique Channel (W Indian Ocean).     

Taxonomic Studies on the Marine Genera Aktedrilus Knöllner and Bacescuella Hrabe' (Oligochaeta, Tubificidae), with Descriptions of Seven New Species

The taxonomy and morphology of Aktedrilus Knöllner, 1935 and Bacescuella Hrabe' 1973 (subfamily Phallodrilinae), both common genera of the marine, littoral meiofauna, were studied on the basis of material from various geographical areas. A. monospermathecus Knöllner, 1935 is redescribed from France and Scotland. A. magnus sp.n., A. hrevis sp.n., A. curvipenis sp.n. and A. floridensis sp.n. are described from Italy, Brazil, France and Florida, respectively. Two very closely related forms are described from the Pacific: A. locyi sp.n. (California) and A. parviprostatus sp.n. (Great Barrier Reef). B. mediterranea sp.n. is described from Italy, and new European records are given forB. arclica Erséus, 1978 andfi. parvithecata Erséus, 1978. Both genera are characterized by having two pairs of prostate glands, well developed penes, and unpaired, mid-dorsal spermatheca (if present). The species of Bacescuella transfer their sperm by means of external spermatophores, structures that are not developed in Aktedrilus. The eight species of Aktedrilus are largely distinguished by means of the morphology of the spermatheca, penes and prostates. The four species of Bacescuella differ principally from each other in the length of the vasa deferentia, and in the morphology of the prostates and copulatory organs. Most Bacescuella species lack spermatheca.     

Redescriptions of Phallodrilus parthenopaeus Pierantoni and P. obscurus Cook (Oligochaeta, Tubificidae)

The type species of Phallodrilus Pierantoni, 1902, P. parthenopaeus Pierantoni, 1902; is redescribed on the basis of new material from W Scotland. The species is characterized by its specific spermathecal and penial setae, its very slender atria, and its long spermathecal ducts. Sexually fully mature specimens of P. obscurus Cook, 1969 are described for the first time, on the basis of material from New Jersey (E USA). The new material shows that this species possesses 5 to 9 penial setae in each ventral bundle of segment XI, and that its atria are coated with a relatively thick musculature.     

New species of the genus Trichodrilus (Oligochaeta, Lumbriculidae)

Five new species of the genus Trichodrilus are described: Trichodrilus longipenis. sp. n. T: rouchi sp. n. T. capilliformis sp. n. and T. angelieri sp. n. from hyporhcic waters of the Iberian Peninsula and France. and T. bonheurensis sp. n. from superticial waters of France. The new taxa contribute with some new features to an amended diagnosis of the genus: presence of modified penial setae, four pairs of spermathecae, hair-like dorsal setae and glandular pads in the epidermis.     

Sylphella puccoon gen. n., sp. n. and two additional new species of aquatic oligochaetes (Lumbriculidae,Clitellata) from poorly-known lotic habitats in North Carolina (USA)

Three new species of Lumbriculidae were collected from floodplain seeps and small streams in southeastern North America. Some of these habitats are naturally acidic. Sylphella puccoon gen. n., sp. n. has prosoporous male ducts in X–XI, and spermathecae in XII–XIII. Muscular, spherical atrial ampullae and acuminate penial sheaths distinguish this monotypic new genus from other lumbriculid genera having similar arrangements of reproductive organs. Cookidrilus pocosinus sp. n. resembles its two subterranean, Palearctic congeners in the arrangement of reproductive organs, but is easily distinguished by the position of the spermathecal pores in front of the chaetae in X–XIII. Stylodrilus coreyi sp. n. differs from congeners having simple-pointed chaetae and elongate atria primarily by the structure of the male duct and the large clusters of prostate cells. Streams and wetlands of Southeastern USA have a remarkably high diversity of endemic lumbriculids, and these poorly-known invertebrates should be considered in conservation efforts.     

Two New Genera of Marine Tubificidae (Oligochaeta) from Australia's Great Barrier Reef

Macquaridriloides gen.n. is established for M. heronae from Heron Reef in Queensland, Australia. The species is characterized principally by its lack of spermathecae, and its elaborate male efferent ducts, each of which consists of (1) a ciliated vas deferens, (2) a ciliated and muscular atrium with diffuse prostates, and (3) a stout muscular, non-ciliar ejaculatory duct opening into a large copulatory sac surrounded by posterior prostates. The genus appears closely related to Macquaridrilus Jamieson, 1968, the habitat and zoogeography of which are briefly discussed. Heronidrilus gen.n. is established for H. fastigatus sp.n. and H. bihamis sp.n. both from Heron Reef. This genus is closely related to Macquaridriloides , but the two species differ from M. heronae in that they possess spermathecae and lack ejaculatory ducts.     

Tubificidae (oligochaeta) from the Ross Sea (Antarctica), with descriptions of one new genus and two new species

Three species,Torodrilus gelidus sp. nov. (subfamily Rhyacodrilinae),Rossidrilus terraenovae gen. et sp. nov. (Limnodriloidinae), and a second unnamed species of Limnodriloidinae, are reported from marine sediments in Terra Nova Bay, Ross Sea. Torodrilus gelidus is distinguished fromT. lowryi Cook, 1970 by its setal pattern (with few exceptions, both anterior and posterior setae are single-pointed in sexually mature specimens ofT. gelidus) and the morphology of its male protuberances (the latter folded over a midventral bursa in segment XI).Rossidrilus terraenovae is characterized by large diverticula attached to the oesophagus in the posterior part of segment IX, unpaired male and spermathecal pores, heavily muscular and entally ciliated atrial ampullae, elongate prostatic pads, and a deep, unpaired and muscular, copulatory sac. It is the first species of its subfamily to be described from Antarctic waters.     

Taxonomic Revision of the Marine Genera Bathydrilus Cook and Macroseta Erséus (Oligochaeta, Tubificidae), with Descriptions of Six New Species and Subspecies

Macroseta Erséus, 1975 is considered a junior synonym to Bathydrilus Cook, 1970 after examination of the type material of B. asymmetricus Cook, 1970. Bathydrilus is defined mainly by its organization of the male duct: vas deferens entering ectal half of atrium, one prostate gland attached to ectal part of atrium, near entrance of vas deferens, another prostate attached to apical, ental end of atrium. B. atlanticus sp.n., B. hadalis sp.n., B. meridianus sp.n., B. graciliatriatus sp.n. and B. longus sp.n. are described from specimens collected from various parts of the world; most of the species are deep-sea forms. Phallodrilus rohdei Jamieson, 1977 and Phallodrilus adriaticus Hrabe', 1971 are transferred to Bathydrilus , and a Caribbean/Bermudian form is described as B. adriaticus trisetosus subsp.n. The taxonomy and morphology of the different species, including B. rarisetis (Erséus, 1975) comb.n., are discussed. Bathydrilus is included in the sub-family Phallodrilinae. It appears closely related to Phallodrilus Pierantoni, 1902, from which it is distinguished principally by differences in the relative positions of the vasa deferentia, the atria and the prostate glands.     

A test of monophyly of the gutless Phallodrilinae (Oligochaeta, Tubificidae) and the use of a 573-bp region of the mitochondrial cytochrome oxidase I gene in analysis of annelid phylogeny

A 573-bp region of the mitochondrial gene cytochrome c oxidase subunit I (COI) of two species of Inanidrilus Erséus and four species of Olavius Erséus (Phallodrilinae, Tubificidae) is used in a parsimony analysis together with a selection of 35 other annelids (including members of Polychaeta, Pogonophora, Aphanoneura, and the clitellate taxa Tubificidae, Enchytraeidae, Naididae, Lumbriculidae, Haplotaxidae, Lumbricidae, Criodrilidae, Branchiobdellida and Hirudinea), and with two molluscs as outgroups. The data support the monophyly of the Olavius and Inanidrilus group, with a monophyletic Inanidrilus . However, parsimony jackknife analyses show that most of the other groups are unsupported by the data set, thus revealing a large amount of homoplasy in the selected gene region. Practically no information is given of within/between family relationships except for a few, closely related species. This suggests that the analysed COI region is not useful, when used alone, for inferring higher level relationships among the annelids.     

Inanidrilus bulbosus gen. et sp.n., a Marine Tubificid (Oligochaeta) from Florida, USA

Inanidrilus bulbosus gen. et sp.n. is described from subtidal sands near Miami, Florida. The species lacks alimentary canal, but it possesses highly modified penial setae and an unpaired dorsal spermatheca. It appears closely related to Phallodrilus Pierantoni, but since it is devoid of anterior prostate glands, which are attached to the ental ends of the atria in Phallodrilus , a new monotypic genus, Inanidrilus gen.n., is established.     

A new lumbriculid genus and species from North America (Clitellata,Lumbriculidae)

Secubelmis limpida n. sp., n. gen., is described from Montana, U.S.A. The monotypic genus resembles the lumbriculid genera Rhynchelmis and Tatriella in having atria in X, spermathecae in VIII, and semi-prosoporous male ducts. It differs from Tatriella in having paired atria and spermathecae, and from Rhynchelmis in having petiolate atria. The single prostate gland is unique within the Lumbriculidae. The new species appears to have a restricted range in the northern Rocky Mountains.     

A generic revision of the Phallodrilinae (Oligochaeta, Tubificidae)

The generic classification of the subfamily Phallodrilinae (with a total of 252 species) is revised according to phylogenetic principles. Morphological character patterns are assessed under the principle of maximum parsimony, but due to the poor resolution and instability in the resulting cladograms, the analysis is supplemented with intuitive weighting of synapomorphic similarities. Thirty-one genera are recognized. The former definition of the type genus Phallodrilus Picrantoni, 1902, is revised and the members of this genus are reclassified into 20 taxa, each hypothesized to be monophyletic: Phallodrilus s.str . (revised to contain the type species only), Somalidrilus gcn.n., Milliganius gen.n., Phallodriloides gen.n., Albanidrilus gen.n., Abyssidrilus gen.n., Paraktedrilus gen.n., Uniporodrilus Erséus, 1979, Inermidrilus gen.n., Gianius gen.n., Mexidrilus gen.n., Peosidrilus Baker & Erséus, 1979, Atlantidrilus Erséus, 1983, Thalassodrilus Brinkhurst, 1963, Pirodrilus gen.n., Pirodriloides gen.n., Marionidrilus gen.n., Pectinodrilus gen.n., Pacifidrilus gen.n. and Pseudospiridion gen.n. Nine new species are described from the Northwest Atlantic: Phallodriloides pinnulatus sp.n., Abyssidrilus opulentus sp.n., A. potens sp.n., A. altoides sp.n., Mexidrilus obtusus sp.n., Peosidrilus dalei sp.n., P. aduncus sp.n., P. riseri sp.n., and Atlantidrilus hamulus sp.n. The genus Discordiprostatus Baker, 1982, is synonymized with Nootkadrilus Baker, 1982.