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.     

An unusual blood sequestering tapeworm (Sanguilevator yearsleyi n. gen., n. sp.) from Borneo with description of Cathetocephalus resendezi n. sp. from Mexico and molecular support for the recognition of the order Cathetocephalidea (Platyhelminthes: Eucestoda)

Sanguilevator yearsleyi n. gen., n. sp. and Cathetocephalus resendezi n. sp. are described from the Broadfin shark, Lamiopsis temmincki, in Malaysian Borneo and Carcharhinus leucas in Mexico, respectively. The new genus is unusual in its possession of internal chambers and channels in its scolex that appear to house extensive quantities of host white and red blood cells, respectively. Histology reveals an extremely intimate association between host tissue and the surface of the apical pad of the scolex. Positive staining with periodic acid-Schiff of the surface of the pad of the scolex and the linings of the chambers and channels suggests that an adhesive substance may be produced in these regions. However, explanations for how and why host blood cells come to reside within the scolex remain elusive. Cathetocephalus resendezi n. sp. is distinctive in the form of the papillae in the papillate band of the scolex and also in the inconspicuous nature of the rugose base of the scolex. Scanning electron microscopy of both new taxa as well as Cathetocephalus thatcheri, Cathetocephalus australis and an undescribed species of Cathetocephalus collected from Carcharhinus amboinensis in Australia, suggests that the papillae surrounding the pad of the scolex are of significant taxonomic utility in distinguishing among species in these groups. Parsimony and Bayesian analyses of sequence data (766 bases of 18S rDNA and 405 bases of 28S rDNA) generated from ethanol preserved specimens of C. thatcheri and S. yearsleyi, when compared with equivalent data available for 40 cestode species in GenBank, resulted in trees that support previous propositions that Cathetocephalus should be placed in the order Cathetocephalidea. The results suggest that Sanguilevator should also be considered to belong to this order.     

Molaetherium heissigi n. gen., n. sp., an unusual mammal from the Early Oligocene of Germany (Mammalia: Palaeanodonta)

A new genus and species of epoicotheriid,Molaetherium heissigi, is described from the Early Oligocene of Grafenmühle 22, near Pappenheim, Bavaria. It is a tiny, highly fossorial form, closely related to the North American genusEpoicotherium. Asia is considered the center of origin of the suborder Palaeanodonta; from there it dispersed to North America and Europe.     

Sarcocystis lindsayi n. sp. (Protozoa: Sarcocystidae) from the South American opossum, Didelphis albiventris from Brazil

A new species, Sarcocystis lindsayi n. sp., is proposed for a parasite resembling Sarcocystis falcatula. It was obtained from the lungs and muscles of budgerigars (Melopsittacus undulatus) fed sporocysts from a naturally-infected South American opossum, Didelphis albiventris, from Jaboticabal, Brazil. Sarcocysts of S. lindsayi n. sp. in budgerigars are microscopic, up to 600 microm long and up to 50 microm wide. The cyst wall is up to 2 microm thick. Ultrastructurally, the sarcocyst wall consists of numerous slender villar protrusions (up to 2.0 microm long and up to 0.3 microm wide), each with a stylet at its tip. Schizonts in cell culture divide by endopolygeny leaving a residual body. Sporocysts are approximately 12 x 7 microm. The parasite is genetically distinct from other organisms that also cycle between opossums and avian species and resemble S. falcatula. Diagnostic genetic variation has been observed in the nuclear large subunit ribosomal RNA gene, the internal transcribed spacer (ITS-1), and each of two other genetic loci. Although the structure of the sarcocyst wall may not provide sufficient grounds for differential diagnosis, several other attributes including schizont morphology and genetic variation at each of these genetic loci permit identification of S. lindsayi n. sp.. Natural intermediate hosts for S. lindsayi n. sp. are not known, and fuller characterization of these and other Sarcocystis species would benefit from experimental avian hosts that are more permissive to the maturation of sarcocysts.     

Calispadella alata n. gen., n. sp., the first chaetognath recorded from a hydrothermal vent site (Mid-Atlantic Ridge)

Calispadella alata n. gen., n. sp., is the first chaetognathdescribed from a hydrothermal vent field (Mid-Atlantic Ridge,depth 1600 m). It belongs to the family Spadellidae (presenceof transverse muscles in trunk and long tail segment). Thereis a pair of lateral fins making no contact with the body posteriorly;these free wing-like extensions end in festoons provided distallywith patches of adhesive cells. This unique feature in a deepbentho-planktonic species can be seen as an adaptation to adhereat times to the substrate to resist local turbulences producedby the hydrothermal fluids. This may also indicate that thisnew genus is phylogenetically close to the neritic genus Paraspadella,which has adhesive finger-like processes. Calispadella alatais sexually precocious as reported for other deep chaetognaths,contrary to most deep living organisms which exhibit delayedsexual maturity. This feature might be a means to increase thepossibility of mating in scarce populations.     

Sauertylenchus labiodiscus n. gen., n. sp., from Australia (Nematoda:Tylenchorhynchinae)

Sauertylenchus labiodiscus n. gem, n. sp. is described and illustrated from soil around Rhagodia sp. in Australia. It can be distinguished from the most closely related genus Tylenchorhynchus Cobb, 1913 by the distinctly set-off, rounded, lip region with a conspicuous labial disc, and long thin stylet. The face view and spicules of Sauertylenchus labiodiscus are illustrated with scanning electron micrographs. The subfamilies Tylenchorhynchinae and Merlininae ale discussed.     

Yunotrechus diannanensis n. gen., n. sp., the first troglobitic trechine (Coleoptera: Carabidae) from a tropical area of China

In the present paper Yunotrechus diannanensis n. gen., n. sp. is described and illustrated from two limestone caves which are close to each other in Wenshan and Maguan counties of southern Yunnan Province, southwestern China. Yunotrechus is an anophthalmoid, not directly related to any hypogean trechine genera hitherto known in Yunnan or in southeastern Asian countries because all of them are aphaenopsoids, with elongated prothorax and tumid propleura. The phylogenetic position of Yunotrechus within Trechinae in China or southeastern Asia remains unclear, although it may be related to Superbotrechus Deuve & Tian 2009, which was recorded from western Hubei Province, central China, and Sichuanotrechus Deuve 2006, which was recorded from northern Sichuan Province, southwestern China. Y. diannanensis n. sp. is the first troglobitic trechine beetle discovered in a tropical area of China.     

Lusitaneura covensis n. gen., n. sp., first Caloneurodea from the Carboniferous of Portugal (Insecta: Pterygota: Panorthoptera)

Lusitaneura covensis n. gen., n. sp., from the Late Carboniferous (Lower Stephanian C) of the Douro Basin (NW of Portugal), is the first Portuguese representative of the Palaeozoic insect order Caloneurodea.     

Galaxitaenia toloi n. gen., n. sp. (Eucestoda: Pseudophyllidea) from Galaxias platei (Pisces: Osmeriformes, Galaxiidae), in the Patagonian region of Argentina

Galaxitaenia n. gen. (Eucestoda: Pseudophyllidea) is proposed to accommodate Galaxitaenia toloi n. gen., n. sp. from Galaxias platei, a freshwater fish inhabiting Andean lakes in Argentine Patagonia. Galaxitaenia belongs to the Triaenophoridae because it possesses a marginal genital pore, a ventral uterine pore, and a follicular vitelline gland. The new genus can be distinguished from other triaenophorids by the following combination of characters: a scolex with a prominent rectangular apical disc without hooks, grooves, or indentations; neck present; segments wider than long to quadrangular; testes in 2 lateral fields, often connected anteriorly; cirrus unarmed; an ovary situated posteriorly; a vagina posterior to the cirrus sac; vitelline follicles medullary, in 2 ventral fields forming 2 wings interrupted medially; a uterus saccate to branched; and eggs without operculum. The types, distribution, and density of microtriches were analyzed on the surface of the tegument of scolex, neck, and immature segments. The presence of tumuli were observed on the apical disc of the scolex. Galaxitaenia toloi n. sp. is the first triaenophorid species recorded in a South American freshwater fish and the fourth helminth parasitizing the intestine of G. platei.     

Saetheriella amplicristata gen. n., sp. n., a new Orthocladiinae (Diptera: Chironomidae) from Tennessee

The generic diagnosis of the male imago of a new genus of the subfamily Orthocladiinae (Chironomidae), Saetheriella is given. The genus is characterized by protruding, hairy eyes; antenna with straight, apical seta; antepronotum reduced; squama without setae; Cu₁ distinctly downcurved; and anal point short, triangular, covered with microtrichia and with two strong, lateral setae. The genus is close to Gynnidocladius Sublette & Wirth, Unniella Sæther and Parakiefferiella Thienemann. The distribution of the genera shows evidence of a Gondwanian connection. The male imago of the only included species S. amplicristata sp. n. is described.     

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.     

The unique lungworms (Nematoda: Metastrongyloidea) of the opossum (Didelphis marsupialis linnaeus)

Summary Prestwoodia delicata (Travassos, 1946) Anderson, 1978, Heterostrongylus heterostrongylus Travassos, 1925 and Didelphostrongylus hayesi Prestwood, 1976 are redescribed on the basis of new collections of specimens from Didelphis marsupialis from North and South America. The three genera are unique to the opossum. Prestwoodia from the nasal sinuses is most similar to Troglostrongylus of Felidae. Heterostrongylus and Didelphostrongylus are similar in size and certain other features such as their six prominent lips and reduced bursae. The dorsal ray in the former, however, consists of a large, rounded lobe whereas in the latter, it is divided into two long branches. Didelphostrongylus is found under the pleura whereas Heterostrongylus is found in the bronchi. ac]19790102