Pseudomastus deltaicus gen. et sp.n. (Polychaeta: Capitellidae) from a shallow water bay in the North- Western Mediterranean Sea

Specimens of Pseudomastus deltaicus gen. et sp.n. (Capitellidae), were collected from muddy bottoms in Els Alfacs Bay (Ebre Delta), a semi-enclosed shallow water area. The main diagnostic characteristics are the possession of 12 thoracic setigers, of which the first 10 have only capillary setae and the last two have capillary notosetae and neuropodial hooded hooks, and presence of branchiae in the abdominal region. Pygidium bearing three anal cirri.     

Acanthopale perkinsi gen. et sp.n. (Polychaeta, Chrysopetalidae) from Cuba and Florida

Acanthopale perkinsi gen. et spa, from coral reefs near the Isle of Pines, Cuba, and from off the coast of Florida is described. The genus is characterized principally by the shape and distribution of paleae, insertion of the median antenna, and presence of a caruncle and a mouth cover. Notosetae (paleae) are similar in shape to the stalks of a rosebush, with two perpendicular series of alternate spines. Paleae of the anterior group are approximately one third the length of those of the posterior group, which are very long and slender. The new genus is discussed and compared with the other genera of Chrysopetalidae.     

Syllidae (Annelida, Polychaeta) from the Caribbean coast of Venezuela

Venezuela possesses a great variety of coastal environments allowing for a high diversity of marine species. However, systematic studies on marine invertebrates are scarce, especially on polychaetes. The family Syllidae is poorly known, and only 14 genera and 42 species have been reported from this country. A total of 13 genera and 26 species the Syllidae were identified from benthic samples collected on different substrata of the northeastern coast of Venezuela. Of these, seven genera and 16 species constitute new records for Venezuela: Odontosyllis guillermoi, Syllides floridanus, Salvatoria clavata, Salvatoria limbata, Sphaerosyllis longicauda, Parapionosyllis longicirrata, Trypanosyllis parvidentata, Trypanosyllis vittigera, Opisthosyllis sp., Syllis amica, Syllis armillaris, Syllis gracilis, Syllis pseudoarmillaris, Syllis vittata, Parasphaerosyllis indica and Myrianida convoluta.     

Sabellaria wilsoni sp.n. (Polychaeta, Sabellariidae) from the southeast coast of Brazil

A new species of Sabellaria is described from the southeast coast of Brazil and compared with related species known from South or North America.     

Polkepsilonema mombasae gen. et sp.n. andPternepsilonema servaesae gen. et sp.n. (Nematoda,Epsilonematidae) from East African coasts

Two new genera and species from Kenyan tidal areas,Polkepsilonema mombasae gen. et sp.n. andPternepsilonema servaesae gen. et sp.n., are described. Both are characterized by the presence of at least fourteen subcephalic setae and by thick thorns on the ventral body region of males. In the first genus, eight to ten subcephalic setae are situated anterior to the amphid, and the ambulatory setae are bisinuous. In the second, the subcephalic setae are situated at the posterior edge of the rostrum, and the ambulatory setae are straight.A key to the 13 genera of the Epsilonematidae is presented.Abbreviations a body length divided by maximum body diameter - abd body diameter at level of anus - amph % diameter of amphid as a percent of head diameter - Asl length of anteriormost ambulatory seta of external subventral row - b body length divided by pharyngeal length - c body length divided by tail length - cs length of cephalic setae - dcs distance from rostrum edge to cephalic setae - gub length of gubernaculum - L body length - lct length of copulatory thorns - lpt length of precloacal thorns - mbd maximum body diameter of posterior body region - (mdb) minimum body diameter - mbd/(mbd) maximum body diameter divided by minimum body diameter - mbd ph body diameter at level of pharyngeal bulb - N number of body rings - ph length of pharynx - spic length of spicule measured along the arc - SSph length of subdorsal somatic setae in pharyngeal region - t tail length - tmr length of nonannulated tail region - V position of vulva as a percentage of total body length from anterior     

Sphinctocystis phyllodoces gen. n., sp. n. (Eugregarinida: Lecudinidae)--a new gregarine from Phyllodoce citrina (Polychaeta: Phyllodocidae)

A new species of aseptate gregarine, Sphinctocystis phyllodoces gen. n., sp. n., from the gut of a polychaete Phyllodoce citrina Malmgren, 1865 from White Sea is described. The electron and light microscopic data on trophozoits are presented. Taxonomy of the described species is discussed. Certain ultrastructural characters are included in generic and specific diagnoses. Order Eugregarinida Leger, 1900; suborder Aseptata Chakravarty, 1960; family Lecudinidae Kamm, 1922. GENUS: Sphinctocystis gen. n. TYPE SPECIES: Sphinctocystis phyllodoces sp. n. DIAGNOSIS: Characters of the family. Free trophozoits elongated, often with several annular constrictions. Anterior end asymmetric, without hooks, not separated from the body, with small apical papilla encircled by smooth area. Epicyte "classical", without additional axial formations at the tops of folds; epicytic folds high, monomorphic in cross sections, finger-shaped, with parallel sidewalls. In the gut of polychaetes. DIFFERENTIAL DIAGNOSIS: The new genus differs from Lecudina by having asymmetric anterior end, developed smooth area around the apical papilla, and monomorphic epicytic folds looking finger-shaped in cross sections. It also differs from Lankesteria by the absence of additional axial formations at the tops of the epicytic folds. It differs from both named genera by presence of annular constrictions on the trophozoit body. Sphinctocystis phyllodoces sp. n. DIAGNOSIS: Characters of the genus. Free trophozoits elongated, large, up to 617 x x 77 um. The average height of epicytic folds 976 nm, thickness 194 nm; there are 6-8 apical filaments and rippled dense structures per fold. Nucleus spherical (ellipsoid after fixation), 24-52 microm along longest axis, localised in anterior third of the body, carries several karyosomes of various size; 25-30 nm thick fibrils (possible fragments of nucleolonema) may be present in karyolymph. Other stages unknown. TYPE SERIES: Microscope preparation with 7 trophozoits, Karacci's haematoxylin stained, is kept in the Zoological museum of the Moscow State University (collection number: Z-1). TYPE HOST: Phyllodoce citrina Malmgren, 1865 (Polychaeta: Phyllodocidae). LOCALISATION: Mid-gut. TYPE LOCALITY: White Sea Biological Station of the Moscow State University, Yeremeyevsky Rapid, Velikaya Salma Strait, Kandalaksha Bay, White Sea.     

Sphaerodoridae (Annelida, Polychaeta) from the region of the Gibraltar Strait with description of Euritmia hamulisetosa gen. et sp.n.

Euritmia hamulisetosa gen. et sp. n. is characterized by many rows of sessile macrotubercles without terminal papillae; all anterior appendages are short and setae simple. Three others species of Sphaerodoridae collected from the Gibraltar Strait region are Ephesiella abyssorum, Sphaerodoridium claparedeii and Sphaerodoropsis minutum. Sphaerodoropsis capense (Day, 1963) is transferred to the new genus Euritmia .     

Trochonerilla mobilis gen. et sp.n., a meiofaunal nerillid (Annelida, Polychaeta) from a marine aquarium in Moscow

A nerillid species new to science is described from the marine aquarium system of Moscow Zoo. Trochonerilla mobilis gen. et sp.n. is characterized by eight chaetigerous segments, three antennae, absence of palps, parapodia with two bundles of simple chaetae and pygidium with two anal cirri. In contrast to other eight-segmented nerillids, Trochonerilla mobilis are very active and mobile animals. They are also able to swim through the water column by means of the strong ring of cilia on the first chaetigerous segment. Their geographical origin is unknown.     

Rostromysis bacescuii gen. et sp. nov. and Megalopsis den-ticauda gen. et sp. nov. (Crustacea -- Mysidacea) from the south-west coast of Australia

Rostromysis bacescuii gen. et sp. nov. and Megalopsis denlicaudagen. et sp. nov. belonging to the tribe Leptomysini are describedfrom the south-west coast of Australia. The characters uniqueto the genus Rostromysis are the unusually long club-shapedrostrum and the large delicate lamella-like pleopods of thefemale, thus easily distinguishing it from the allied generaTenagomysis and Doxomysis. The genus Megalopsis is closely alliedto Leptomysis, Prionomysis and Promysis but is readily distinguishablein having a short linguiform uncleft telson with a pair of medianplumose setae.     

Crepidula beklemishevi gen. et sp. n. and Dimeiospora palustris gen. et sp. n. (Microspora: Amblyosporidae)--new microsporidian genera and species from blood-sucking mosquitoes (Diptera: Culicidae) from the south of the western Siberia

Microsporidia parasitizing the adipose body of mosquito larvae of Anopheles beklemishevi and Aedes punctor has been studied. Two new genera of microsporidia are described based on lightmicroscopic and ultrastructural characteristics of spores and sporogony stages. The spore wall of Crepidula beklemishevi gen. n. et sp. n. is formed by two-membrane exospore, thick exospore, bilayer endospore and thin plasmolemma. Spores with single nucleus, polar filament anisofilar, with 6-7 coils (2+ 4-5), polaroplast consisting of three parts: macrochelicoidal, microhelicoidal and lamellar. Fixed spores 4.2 +/- 0.22 x 2 +/- 0.01 microns. The sporogony of Dimeiospora palustris gen. et. n. results in spore formation of two different types. Spores of the first type are oviform, with thick wall, single-nuclear, 6.1 x 4.9 microns. Spore wall with three layers, about 370 nm. Exospore electron-dense, subexospore moderately electrondense. Exospore and subexospore irregularly pleated on the almost spore surface and slightly thinner on anterior end only. Endospore electron-translucent. Polar filament anisofilar, with 9 coils (3 + 6). Polaroplas consists of three parts: lamellar, fine bubbled, and coarse bubbled. Spores of the second type broad-ovate, with apical pole narrower, distal pole concave, 4.6 x 3.7 microns. Spore wall with three layer, 355 nm. Exospore on the apical end irregularly pleated, consists of thin electrondense exospore, subexospore of variable electron density, endospore electron-translucent. Polar filament anisofilar, with 13 coils (3 + 10). Polaroplast has two parts: lamellar and vesicular.     

Platynereis nadiae sp. n. (Polychaeta: Nereididae) from Italian coasts

A new species, Platynereis nadiae sp. n. (Polychacta: Ncrcididac), from thc Mediterranean Sea is described. It is clearly distinguished from the other Platynereis species by the distribution and the morphology of the homogomph falciger setae and by the structure of thc tcntacular cirri.     

Procyonostrongylus muelleri gen. et sp. n. (Metastrongyloidea: Angiostrongylidae) from the raccoon (Procyon l. lotor)

Procyonostrongylus muelleri gen. et sp. n. from under the epithelium of the epiglottis of Procyon l. lotor is distinguished by 1) the absence of lips; 2) a highly developed reinforced bursa with a deep terminal incision; 3) highly developed toothlike dorsal rays; 1) greatly reduced externodorsal rays; and 5) the terminal or subterminal anus and vulva in the female.     

Didelphostrongylus hayesi gen. et sp. n. (Metastrogyloidea: Filaroididae) from the opossum, Didelphis marsupialis.

Didelphostrongylus hayesi gen. et sp. n. from the opossum, Didelphis marsupialis, is distinguished from other genera of the Angoistrongylinae by the structure of the dorsal and lateral rays, complex gubernaculum, and ovoviviparity. Third-stage larvae developed in Mesodon perigraptus and Triodopsis albolabris. The prepatent period was 22 days in experimentally infected opossums.     

Antaretylus humus n. gen., n. sp. from the Subantarctic (Nematoda: Tylenchoidea)

Antarctylus humus n. gen., n. sp. from peat soil in the subantarctic is proposed. It can be distinguished from the most closely related genus Helicotylenchus by the arrangement of the esophageal glands, the broadly rounded lip region, and the tapering pointed tail in the female.