A new species of Polystomoides ward, 1917 (Monogenea: polystomatidae) from freshwater chelonians (Testudines: chelidae) in Brazil

This report describes the first occurrence of Polystomoides brasiliensis n. sp. (Monogenea: Polystomatidae), a new monogenean species in the buccal and pharyngeal cavities of the freshwater turtles in Brazil. Live monogeneans were collected from Hydromedusa maximiliani and Phrynops geoffroanus at the Mariano Procópio Museum's lake, in Juiz de Fora, Minas Gerais, Brazil. Polystomoides brasiliensis differs from all other species of this genus in having 8-9 genital spines, except for Polystomoides uruguayensis, which has 8-10 genital spines. However, the new species differs morphometrically from P. uruguayensis in the greater size of the outer and inner hamuli, as well as having a testis that is proportionally greater than the pharynx and oral sucker. The current study is the first report of monogeneans in chelonians of Brazil, and the first record of helminths in H. maximiliani.     

Six new species of Lepidapedon Stafford, 1904 (Digenea: Lepocreadiidae) from deep-sea macrourid fishes from the Gulf of Mexico and Caribbean Sea, with revised keys to the species of the genus

Species of the genus Lepidapedon are divided into various groups and subgroups based on vitelline distribution relative to the acetabulum and anterior extent of the excretory vesicle. Members of this genus predominantly parasitise gadiform fishes and are commonly collected from relatively deep waters. A recent study of deep-sea helminths from macrourids of the Gulf of Mexico and Caribbean Sea revealed six new species of this genus. L. mexicanensis n. sp., of the elongatum group, elongatum subgroup, differs from other species in this subgroup in proportions (as % of body length), lacking confluent vitelline fields between both the ovary and anterior testis and the testes, and in having a smaller egg and body size. L. nezumiatis n. sp., of the elongatum group, desclersae subgroup, differs from both L. filiformis and L. desclersae in having intermediate egg and body sizes, and a longer oesophagus than prepharynx. L. caribbaei n. sp. and L. longivesicula n. sp., of the garrardi group, congeri subgroup, differ from L. congeri in having a sucker-ratio of 1:<1. L. caribbaei n. sp. and L. longivesicula n. sp. differ from each other in that L. caribbaei n. sp. has numerous long, barb-like, deeply imbedded spines, a less elongate body, an infundibuliform oral sucker, a similar-sized oesophagus and prepharynx, and a caecal bifurcation which is closer to the acetabulum than oral sucker, while L. longivesicula n. sp. has shorter, serrate or plate-like, lightly imbedded, widely to sporadically spaced spines, a more elongate body, a spherical to subspherical oral sucker, a longer oesophagus than prepharynx, and a caecal bifurcation which is closer to the oral sucker than acetabulum. L. desotoensis n. sp., of the rachion group, rachion subgroup, is distinct from both L. luteum and L. abyssensis in having a smaller size, lacking cervical glands or pharyngeal gland cells, and possessing dark-staining particles in the mesenchyme, while it differs from L. abyssensis specifically in having a much longer oesophagus than prepharynx, lateral vitelline fields that are not confluent intertesticularly, and wider eggs. L. zaniophori n. sp., also of the rachion subgroup, differs from both L. cascadensis and L. genge in having a smaller egg size, a shorter prepharynx and oesophagus than pharynx, and vitelline fields that are intertesticular but only slightly encroach between the ovary and anterior testis. L. sammari and L. spiniferi are designated as incertae sedis, and L. quiloni and L. stromateusi are designated as species inquirendae. New parasite keys and host records for Coelorinchus coelorhincus, C. caribbaeus and Nezumia cyrano are offered. Support is given to Lepidapedon probably being the dominant digenean genus in deep water.     

Report on the Polycystididae (Rhabdocoela, Kalyptorhynchia) from Australia, with the Description of Twelve New Species and Six New Genera

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.     

A new species of Gyraulus (Gastropoda: Planorbidae) from Ancient Lake Lugu,Yunnan-Guizhou Plateau,Southwest China

A new aberrant species of the planorbid genus Gyraulus, Gyraulus luguhuensis n. sp., is described from Lake Lugu (Lugu-hu, in Chinese), Southwest China. The generic assignment with Gyraulus is based on features of the genital anatomy that are characteristic for members of that genus, in particular the presence of a chitinized penial stylet. Gyraulus luguhuensis n. sp. differs from most other congeners by its large, thick shell with an elevated spire. Similarly, aberrant shells are known from congeners in other Ancient Lakes worldwide indicating a potentially convergent evolution of shell characteristics in exclusively lacustrine species. Gyraulus luguhuensis differs from other lacustrine Gyraulus species with similarly large shells in having a sub-terminal penis pore and an unkeeled shell.     

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.     

Ultrastructure of the copulatory stylet and accessory spines in Haplopharynx quadristimulus (Turbellaria)

The copulatory organ of Haplopharynx quadristimulus Ax, 1971 (Carolina form, Rieger, 1977) consists of a proximal prostatic vesicle and a distal stylet apparatus comprising a central tubular stylet and four to five peripheral accessory spines. By electron microscopy it could be seen that the stylet and spines were intracellular specializations. The copulatory organ can be interpreted as a specialization of an epithelial canal extending from the testes to the body wall. In the complex stylet apparatus, the epithelium was differentiated into six cell types. The stylet, which was formed in a matrix syncytium next to the prostatic vesicle, extended into the lumen of the stylet canal. The interior of the stylet apparatus contained one group of cells that had thick ciliary rootlets and another that had rootlet-like ribbons.The cells that contain the rootlets enveloped bundles of longitudinally arranged muscles. The accessory spines were formed in cells which lay peripheral to the muscle bundles. The spines, stylet, rootlet-like ribbons, and rootlets had similar patterns of periodic cross striations. The similarity in striation patterns suggests that the accessory spines and stylet are composed of modified ciliary rootlets.     

Descriptions of Chitwoodius brasiliensis n.sp., Chitwoodius rusticulus n.sp., and Vancterlindia venata n.sp. (Dorylaimida: Tylencholaimidae: Vanderlindiinae)

Chitwoodius brasiliensis n.sp. is described from soil around plant roots in Vicosa, MG State, Brazil. It has a body 1.9 mm (1.6-2.5) long, odontostyle and odontophore 33 μm (31-37) and 34 μm (31-36) long, respectively, and males with spicules 59-61 μm long. Chitwoodius rusticulus n.sp. from Colombian rain forest differs from other species of the genus in having a weakly muscular anterior part of the oesophagus, a pore-like vulva, and an unsclerotized vagina. Vanderlindia venata n.sp. from lucerne soil in South Kilimanjaro, Tanzania, differs from the type and only other known species of its genus in having a smaller and less slender body (L = 3.34 mm [3.15-3.71], a = 50 [46-53]), odontostyle 2.3-2.5 times lip region width long, and stylet guiding ring located at 1.2-1.4 times lip region width from anterior end.     

Carassotrema koreanum Park, 1938 (Trematoda, Waretrematidae) and a new species of this genus from fresh water fishes of North Vietnam]

In freshwater fishes of North Viet-Nam were found representatives of the family Waretrematidae, Carassotrema koreanum and a new species of this genus, C. ginezinskajae sp. n., close to C. koreanum and differing from it in the structure and extent of yolk glands, relatively larger sizes of the pharynx and suckers, the location of spines and body shape. The described species differs from the other species of this genus, C. mugilicola, in the shape and location of testis, structure and location of yolk glands, intestine extent, size of suckers and pharynx, presence of cirrus, location of spines on the body and in other characters. Asymphylodora pavlovskajae Ha Ky, 1969 and Asymphylodora ginezinskajae Ha Ky, 1969 are reduced to synonyms of Carassotrema koreanum and C. ginezinskajae sp. n.     

A new species of the genus Goezia Zeder, 1800 (Nematoda: Anisakidae) from the fish,Mastacembelus armatus (Lacep.) from West Bengal,India

Goezia moraveci n. sp. is described from light microscope and scanning electron microscope studies of the specimens recovered from the freshwater fish Mastacembelus armatus from West Bengal, India. G. moraveci differs from other species of the genus in having a small body size, the excretory pore posterior to the level of the nerve-ring, a very short, wide intestinal caecum and a long ventricular appendage (ratio 1: 6–15), a different number and arrangement of caudal papillae, and cuticular spines surrounding the bases of the caudal papillae. This represents the first species of the genus from a piscine host in India.     

Tetrameres (Tetrameres) megaphasmidiata n. sp. (Nematoda: Tetrameridae), a parasite of the two-banded plover, Charadrius falklandicus, and white-rumped sandpiper, Calidris fuscicollis, from Patagonia, Argentina

Tetrameres (Tetrameres) megaphasmidiata n. sp. is described from the proventriculus of the two-banded plover, Charadrius falklandicus, and the white-rumped sandpiper, Calidris fuscicollis, from Patagonia, Argentina. The new species shares with T. (T.) nouveli, T. (T.) paradisea, T. (T.) prozeskyi, T. paraaraliensis, T. (T.) cladorhynchi, and T. lobybicis the absence of the right spicule and the presence of 4 rows of somatic spines. Tetrameres (T.) megaphasmidiata n. sp. differs from the first 4 species mainly by its longer left spicule. The new species can be distinguished from T. (T.) cladorhynchi by the extension of the lateral alae, the number and arrangement of the caudal papillae, and the absence of polar filaments in the eggs. Tetrameres lobybicis differs from the new species by having shorter rows of dorsal spines and a different number and arrangement of the caudal papillae. This report is the first record of a species of Tetrameres in C. falklandicus and C. fuscicollis.     

TWO NEW SPECIES OF THE GENUS ISLAMIA RADOMAN, 1973 FROM ITALIAN ISLANDS (PROSOBRANCHIA, HYDROBIIDAE)

Two new Italian species of the genus Islamia (Prosobranchia:Hydrobiidae), one living in eastern Sicily (I. cianensis), andone on Elba Island (Tuscan Archipelago, Italy) (I. gaiteri)are described. The two species are distinguished on the basisof shell and anatomical characters, mainly those of the malegenitalia. I. cianesis n. sp. is characterized by a valvatoidshell and a penial lobe with internal band of glandular tissuenot distinct in its lower portion from the penis body but bulgingapically as a small knob. I. gaiteri n. sp. is characterizedby a planispiral shell and a small lateral penial lobe withoutinternal glandular tissue. (Received 20 December 1993; accepted 27 June 1994)     

Six new species of Rhamnocercus Monaco,Wood & Mizelle, 1954 (Monogenea: Diplectanidae) infecting the gills from South American sciaenid fishes

A parasitological survey searching diplectanids (Monogenea: Diplecatnidae) infesting the gills of marine fishes from South America was carried out during the 2019–2020 period. The gills of four sciaenid species, 2 Cheilotrema fasciatum Tschudi, 1 smalleye croaker Nebris microps Cuvier, 2 royal highhat Pareques lanfeari (Barton), and 1 minor stardrum Stellifer minor (Tschudi), were sampled. Six new species of Rhamnocercus Monaco, Wood & Mizelle, 1954 were described: Rhamnocercus chacllae n. sp. and Rhamnocercus chaskae n. sp. from P. lanfeari, Rhamnocercus fasciatus n. sp. from C. fasciatum, Rhamnocercus microps n. sp. from N. microps, and Rhamnocercus rimaci n. sp. and Rhamnocercus tantaleani n. sp. from S. minor. Rhamnocercus chacllae n. sp. can be differentiated from its congeners by its L-shaped male copulatory organ (MCO) and by having an anteromedial slight notch at ventral bar. Rhamnocercus chaskae n. sp. differs from the other species of the genus by its long and straight MCO with bifid distal end and by having haptoral accessory spines at level of ventral bar with quadrifid distal portion. Rhamnocercus fasciatus n. sp. is characterized by possessing a straight and long MCO with truncated distal end, haptoral accessory spines at level of ventral bar with bifid distal portion, dorsal bars with a knob at lateral extremity, and a large vagina with bell-shaped. Rhamnocercus microps n. sp. differs from all congeners mainly by having a short and straight MCO with the distal end of internal tube spatulate and uncovered by external tube. Rhamnocercus rimaci n. sp. is can be distinguished from all other species of Rhamnocercus by having an almost J-shaped MCO with the distal end of external tube slight expanded and the distal end of internal tube narrow and uncovered by external tube. Rhamnocercus tantaleani n. sp. is mainly characterized by its MCO, which is tubular and straight, having the distal end of external tube bifurcated (right branch well-expanded and left branch narrow) and the distal end of internal tube enveloped by left branch of the external tube. This is the first data on the parasites of P. lanfeari, a little known, but popular fish in local markets from Peru. Rhamnocercus microps n. sp. is the first described species of Rhamnocercus in Brazil. The present finding brings to 12, the number of known species of Rhamnocercus. A key to Rhamnocercus species is provided.

     

<Emphasis Type="Italic">Petasiger islandicus</Emphasis> n. sp. (Digenea: Echinostomatidae) in the horned grebe <Emphasis Type="Italic">Podiceps auritus</Emphasis> (L.) (Aves: Podicipedidae) from Iceland

Petasiger islandicus n. sp. is described and figured from a demographically isolated population of the horned grebe Podiceps auritus auritus (L.) in Lake Myvatn (Iceland). This new species belongs to the group of species with 19 collar spines which possess a large elongate-oval cirrus-sac, well-developed pars prostatica and massive bulb-like cirrus. Within this group, P. islandicus appears most similar to P. oschmarini Kostadinova & Gibson, 1998, a form with similar body dimensions described from the same host, but differs in having a larger head collar, collar spines, oral sucker, pharynx, testes and sucker-width ratio, and a smaller cirrus-sac, cirrus and eggs. Two Nearctic species resemble P. islandicus in general morphology but differ as follows: P. pseudoneocomense Bravo-Hollis, 1969 has a larger body and collar width, notably shorter collar spines, smaller testes and sucker-width ratio, and a shorter but much wider cirrus-sac which is also smaller relative to the ventral sucker and almost entirely anterior to it; and P. caribbensis Nassi, 1980 has a smaller body, shorter collar spines and a seminal vesicle which is small in relation to the cirrus-sac, vitelline fields reaching anteriorly to the level of the genital pore and the intestinal bifurcation is located more anteriorly.     

A new species of Procolobomatus Castro Romero, 1994 (Copepoda: Philichthyidae) endoparasitic in a deepwater longtail red snapper (Actinopterygii: Lutjanidae) off Ishigaki Island, Japan, with records of philichthyid copepods reported from Asian waters

A new species of the Philichthyidae Vogt, 1877 (Copepoda: Poecilostomatoida), Procolobomatus hoi n. sp., is described based on adult female specimens recovered from the cephalic sensory canals of Etelis coruscans Valenciennes (Actinopterygii: Lutjanidae) caught off Ishigaki Island, the Ryukyu Islands, southern Japan. The new species differs from its congeners by having the following combination of characters: a long medial cephalic lobe about one-third the length of the body; an armature of five spines on the distal exopodal segment of leg 2; one long apical seta on the papillose leg 4; a caudal ramus armed with one medial and four terminal setae (two middle setae are inflated); and spinulose ornamentation covering the body. Procolobomatus hoi n. sp. is the first member of the genus reported from the western Pacific Ocean and from a host of the family Lutjanidae. Previous records of philichthyid copepods from Asian waters are also reported.     

Two New Proschizorhynchus Species from the Coast of Massachusetts, USA (Turbellaria, Kalyptorhynchia)1

Proschizorhynchus nahantensis sp. n. and Proschizorhynchus papillatus sp. n. are described and their taxonomy discussed. P. nahantensis is characterized by its penis papilla which has a proximal spherical and distal tubular portion. A simple stylet is present. The female system is distinguished by the external opening of the vagina and the prominent bursal mouthpiece. P. papillatus is distinguished by the two muscle layers of the copulatory organ, the large straight stylet in the penis papilla, a single gonopore and uterus. Notes on the ecology of the species are included. Views are given on the taxonomy of the genus Proschizorhynchus Meixner, 1928.     

A new species of Gieysztoria (Platyhelminthes, Rhabdocoela) from Argentina and a kinship analysis of South American species of the genus

This study describes a new species of Gieysztoria found in lentic environments in Argentina. Gieysztoria falx sp. n. appears to be closely related to G. therapaina and G. intricata , and is differentiated principally by the presence of two strongly developed pincer-shaped spines of the cuticular stylet. A preliminary analysis of the phylogeny among the South American species of this genus is undertaken, and the monophyly verified. This study constitutes the first approach to interpreting these relationships.     

Comparative ultrastructure of the terminal portions of the male copulatory apparatus in Planorbidae (Gastropoda: Pulmonata)

Terminal portions of the male copulatory apparatus of Planorbis planorbis, Segmentina oelandica, and Anisus vortex were studied using whole-mount preparations, serial semi-thin sections, and transmission electron microscopy. In the latter species, stylet formation was investigated at several stages of postembryonic development. Organization of the penial distal portion in the species studied varies greatly. In P. planorbis, the distal end of the penis lacks developed papillae and is armed with a stylet built up of the covering epithelial cells of the penis proper. In A. vortex, the stylet is formed by the secretory activity of the middle cells of the distal portion of the penis. To the time of maturation, the cells encompassing the stylet are broken down exposing its solid chitinous structure and characteristic shape. In S. oelandica, the distal end of the penis bears the long probably flexible papilla with the characteristics of an internal ‘skeleton,’ organized as a line of connective tissue cells and a system of hydrocoelic cavities.     

5 new species of blackflies (Diptera: Simuliidae) from Siberia, the Far East and Central Asia

Five new species of the family Simuliidae Stegopterna byrrangii Yankovsky, sp. n. and Cnephia chaurensis Yankovsky sp. n., from Taimyr peninsula, Metacnephia olyutorii Yankovsky sp. n. from Kamchatka, Metacnephia karakechensis Yankovsky sp. n. and Montisimulium sonkulense Yankovsky sp. n. from Kirghizia, are described. Stegopterna byrrangii differs from related species: in male--from all known species of the genus by peculiar form of apical end of gonostyles, when apical spine is approximately parallel to inner surface of gonostyle; in female--from all known species of the genus by very long genital lobes (their length twice more than width), from S. longicoxa Rubzov, 1971 and S. duodecimata (Rubzov, 1940) by long stem of genital fork, absence of anterolateral sclerotized projections of branches of genital fork; in pupa--from all known species of the genus by number of filaments of respiratory organ (14-16, when in other species no more than 12). Cnephia chaurensis differs from related species: in male--from C. intermedia Rubzov, 1956 and C. toptchievi Yankovsky, 1996 by absence of medial projection or ridge of gonosternum, from C. intermedia by widened body of gonosternum, from C. toptchievi by ridge on gonocoxites and wide triangular projections near base of arms of gonosternum; in female--from C. intermedia by sclerotized finger-like anterolateral projections of branches of genital fork, subdivision of branches into two lobes, wide flat apical end of stem of genital fork. Metacnephia karakechensis differs from related species: in male--from M. subalpina (Rubzov, 1956) by form of gonostyles, absence of triangular medial projection of gonosternum, short widened gonofurca and more number of spines in parameres, from M. kirjanovae (Rubzov, 1956) and M. slepjani (Rubzov, 1967) by triangular body of gonosternum, widened gonostyles, more number of spines in parameres; in larva--from M. subalpina by more number of rays of primary fan of premandibles, less number of ridges of hooks in posterior attachment organ, from M. kirjanovae by short thick antennae; in pupa--from M. subalpina by character of divergence of upper thick filaments of respiratory organ, from M. kirjanovae by presence of thick filaments of the organ. Metacnephia olyutorii differs from related species: in female--from M. larunae Worobez, 1984 and M. aldanica Worobez, 1987 by thick sclerotized anterolateral projections of branches of genital fork, from M. taimyrica Patrusheva, 1976 by 1-ended (not 3-ended) anterolateral projections of branches of genital fork, large (not shortened) anal lobes, from M. crassifistula (Rubzov, 1956) by very long stem of genital fork. Montisimulium sonkulense differs from related species: in male--from M. brachystylum (Rubzov, 1976) by more prolonged gonostyles, less number of spines of parameres, from M. ocreastylum (Rubzov, 1956) by form of gonostyles, from M. odontostylum (Rubzov, 1947) by more number of spines of parameres; in female--from M. brachystylum and M. odontostylum by stricktly developed posteromedial projections of branches of genital fork, from species having posteromedical projections of branches of genital fork--from M. (ABSTRACT TRUNCATED)