Observations on two Rhabdochona species (Nematoda: Rhabdochonidae) from freshwater fishes in Argentina, including description of Rhabdochona fabianae n. sp

Helminthological examination of specimens of the freshwater fishes Bryconamericus iheringi Boulenger, 1887 (Characidae) and Jenynsia multidentata (Jenyns, 1842) (Anablepidae), collected from Medina River, Province of Tucuman, Argentina, revealed the presence of 2 species of parasitic nematodes, Rhabdochona fabianae n. sp. and Rhabdochona acuminata (Molin, 1860) (Rhabdochonidae). Rhabdochona fabianae n. sp. was characterized by the presence of 16 anterior teeth in the prostom and filamented eggs in females. Rhabdochona acuminata was recorded for the first time in the north of Argentina.     

Rhabdochona parastromatei sp.n. (Nematoda, Rhabdochonidae) from the Fish Parastromateus niger (Bleeker) of the Karachi Coast

Rhabdochona (Rhabdochona) parastromatei sp.n. is characterized by its relatively large body size, 16 teeth in pros tome, right spicule 0.48-0.50 mm and left 0.10-0.12 mm in length, 9–10 pairs of caudal papillae, a single adanal papilla, eggs in female 0.029-0.044 by 0.018-0.025 mm in size, and by having a marine fish host.     

Spinitectus mexicanus n. sp. (Nematoda : Cystidicolidae) from the intestine of the freshwater fish Heterandria bimaculata in Mexico

A new nematode, Spinitectus mexicanus n. sp., is described on the basis of the specimens recovered from the intestine of Heterandria bimaculata (Heckel) (Poeciliidae, Cyprinodontiformes) from 3 rivers of the Papaloapan River basin (type locality La Basura River), Los Tuxtlas, Veracruz State, Mexico. It differs from its congeners mainly in having the spination of the cuticle separated into 4 longitudinal sectors, each with posteriorly diminishing numbers of larger spines at the anterior part of body. It is the first species of Spinitectus described from a poeciliid fish and the second reported from freshwater fishes in Mexico.     

Occurrence and maturation of Rhabdochona gnedini (Nematoda: Rhabdochonidae) in the barbels of the Sousa River, Portugal

Data on the seasonal occurrence and maturation of Rhabdochona gnedini Skrjabin, 1946 in its definitive host, the barbel Barbus bocagei, from the Sousa River, in northern Portugal, are presented. Monthly samples were taken from November, 1998 to October, 1999. A total of 178 fish specimens were inspected. R. gnedini occurred with high prevalences during whole year, attaining the highest values of intensity in summer (overall prevalence and mean intensity 85% and 31, respectively). A clear annual cycle of maturation was observed; females with mature eggs occurred in spring and summer. Unidentified Rhabdochona larvae were recorded from the trichopteran larvae Hydropsyche sp. (prevalence and intensity 29% and one to 34, respectively). These larvae are presumptive intermediate host for R. gnedini.     

Huffmanela mexicana n. sp. (Nematoda: Trichosomoididae) from the marine fish Sphoeroides annulatus in Mexico

A new species of trichosomoidid nematodes, Huffmanela mexicana n. sp., is established on the basis of its egg morphology and biological characters. The dark-shelled, embryonated eggs of this histozoic parasite occur in masses in the inner layer of the swimbladder wall of the bullseye puffer fish Sphoeroides annulatus Jenyns, 1843 (Tetraodontidae, Tetraodontiformes) off the Pacific coast of Mexico (Sinaloa State) and are characterized mainly by their shape and size (63-69 x 30-33 microm), an aspinose surface, relatively small polar plugs, and their thick egg wall (4-5 microm). A key to Huffmanela species based on egg morphology is presented.     

Paracapillaria epinepheli n. sp. (Nematoda: Capillariidae) from the red grouper Epinephelus morio (Pisces) from Mexico

A new nematode species, Paracapillaria epinepheli, is described from the stomach of the marine fish Epinephelus morio (Valenciennes), the red grouper, (Serranidae, Perciformes) from coastal waters of the Gulf of Mexico in Yucatan, southeastern Mexico. It is characterised mainly by its small body (body length of male and female 2.73–3.22 mm and 5.94–6.35 mm, respectively), number (31–36) and structure of the stichocytes, length of the spicule (0.180–0.195 mm), structure of the male caudal bursa (considerably reduced), structure and size of the eggs (size 0.057–0.063 × 0.027–0.030 mm), and by their site within the host. It is the second Paracapillaria species known to occur in the marine and estuarine fishes of the Gulf of Mexico.     

Spirocamallanus cricotus sp. n. and S. halitrophus sp. n. (Nematoda: Camallanidea) from fishes in the northern Gulf of Mexico

Spirocamallanus cricotus sp. n. (= S. pereirai, in part) and S. halitrophus sp. n. are described from marine fishes of the northern Gulf of Mexico. Spirocamallanus cricotus has a ledge anterior to the basal ring in the buccal capsule, similar spicules with a ratio of 1:1.4 to 2.1, 3 pre- and 5 postcloacal papillae, and 8 rectal glands in the female; S. halitrophus lacks the ledge and possesses dissimilar spicules with a ratio of 1:1.3 to 1.8, 3 pre- and 6 postcloacal papillae, and 4 rectal glands in the female.     

Cucullanus bonaerensis n. sp. (Nematoda: Cucullanidae) parasitizing Urophycis brasiliensis (Pisces: Phycidae) from Argentinean waters

A total of 8 specimens of Urophycis brasiliensis (Kaup, 1858) from waters off Mar del Plata, Argentina (38 degrees 08'S, 57 degrees 32'W), were examined for parasitic nematodes. A new nematode species, Cucullanus bonaerensis n. sp., is described (prevalence 50%, mean intensity 15.5). The new species differs from its congeners in the distribution pattern of caudal papillae (particularly fourth pair) and phasmids, length of the body and spicules, and by the position of the excretory pore (in the posterior third of esophagus). Species of Cucullanus, reported previously as C. heterochrous Rudolphi, 1812, and Cucullanus sp. from U. brasiliensis from Puerto Quequén, Argentina (38 degrees 37'S, 58 degrees 53'W), are considered as members of the new species.     

Halalaimus algeriensis n. sp. (Nematoda) from the Sahara

During a trans-Saharan expedition in 1980 a number of samples were collected from stagnant and running fresh and slightly saline water bodies. One of them, collected from the Oued En-Namous in a small oasis yielded several interesting nematodes, among which was a newHalalaimus species described herein asHalalaimus algeriensis n. sp. It comes close toH. minusculus Tchesunov, 1978, but differs in tailshape, absence of males and habitat. It also resembles the marine speciesH. gracilis de Man, 1888, but differs in the relative length of the anterior setae, the absence of a lateral field and absence of males. The new species can be differentiated fromH. stammeri Schneider, 1940, the only fresh water species found hitherto, by its shorter body, more anterior and wider fovea, and the length and position of the anterior setae. The various juvenile stages can be separated on the basis of body length, foveal length and genital primordium.     

A new species of Rhabdochona Railliet, 1916 (Nematoda: Rhabdochonidae) from cyprinid fishes in the Western Ghats Region,India

A new nematode species, Rhabdochona (Globochona) puntii n. sp. (Rhabdochonidae), is described based on specimens collected from the intestine of the pool barb Puntius sophore (Hamilton) and Neolissochilus hexastichus (McClelland) (both Cyprinidae) from the Gadhena River, the Western Ghats, Maharashtra State, India. The nematode was also found in Wallago attu (Bloch & Schneider) which probably acts as postcyclic host. Rhabdochona (Globochona) puntii n. sp. differs markedly from its congeners in the body size, the number and distribution of caudal papillae, in the presence of an unpaired papilla-like structure on the anterior cloacal lip, and in having unusual shape and structure of the terminal crown of mucrons. This is the seventh species of the subgenus Globochona Moravec, 1972 reported from freshwater Indian fishes.     

Heliconema brooksi n. sp. (Nematoda: Physalopteridae) from the ophichthid eel Ophichthus gomesi in the Gulf of Mexico

Heliconema brooksi n. sp. is described from the shrimp eel, Ophichthus gomesi, in Mississippi Sound. This species is distinguished from other members of the genus by possessing in the male 40 or more tessellated longitudinal ridges, a spicule ratio averaging 1:10.6, 4 precloacal papillae, and 6 postcloacal papillae. Females have a protruding vulvular flap. Both sexes have a prominent sclerotized cardium. Heliconema brooksi is morphologically most closely related to Heliconema heliconema. A juvenile worm from the white shrimp, Penaeus setiferus, in the same locality may be the infective stage.     

Coslenchus capsici n. sp. (Nematoda: Tylenchidae) from India

Coslenchus capsici n. sp., from around the roots of Capsicum annuum at Kulu (H.P.), India, is characterized by a large number of cuticular ridges (17+17 + lateral fields), a smooth head with a well-sclerotized framework and a forwardly inclined vagina with swollen walls.     

Trichodorus persicus n. sp. (Nematoda: Trichodoridae) from Iran

Trichodorus persicus n. sp. is described from the Caspian region of Iran, where it was found in woodland and orchard soil. Males of the new species usually have two ventral cervical papillae anterior to the excretory pore but posterior to the base of the onchiostyle; there are three ventromedian preanal supplements, the posterior one lying near the heads of the retracted spicules; the spicules are 51–61 m long with faint transverse striations distally. Females have two pairs of lateral body pores, large rounded sclerotized thickenings at the vulva and the vagina tapers inwards in lateral view.     

Xiphinema bacaniboia n.sp. (Nematoda: Dorylaimida) from Fiji

Summary Xiphinema bacaniboia n.sp. is described from rain forest in Fiji. Adult females are characterized by their spiral shape on heat death, slightly offset lip region, total stylet length of 270–292 m, post-median vulva, paired, opposed genital branches with greater development of the anterior one, absence of a Z organ and the presence of a broadly rounded tail, flattened ventrally with no blind canal. The species is differentiated from X. ingens Luc & Dalmasso, 1964, X. macrostylum Esser, 1966 and X. riocaquetae Hunt, 1982. ac]19830610     

Mylonchulus sessus n.sp. (Nematoda: Mononchida) from Brunei

Summary Mylonchulus sessus n.sp. is described. It is close to M. sigmaturus and M. dentatus and was found in soil from around tomato from Brunei. It has an exceptionally well developed and differentiated female reproductive system which is rather unusual in Mylonchulus and, although close to M. sigmaturus and M. dentatus differs from both in having wider amphids and smaller submedian teeth.     

Criconemella anastomoides n. sp. (Nematoda: Criconematina) from Pakistan

Criconemella anastomoides, described and illustrated herein, is characterized by the presence of regular anastomosis on the body, two zig zag lateral lines, stylet knobs sloping posteriorly, short stylet, and short body length.     

Passeristrongylus amandavae n. g., n. sp. (Nematoda: Trichostrongyloidea) from the small intestine of the passeriform bird Amandava subflava

Summary Passeristrongylus amandavae n. g., n. sp. is described from the small intestine of Amandava subflava, recently imported from Africa. After discussing the systematic classification the new genus is classified within the subfamily Ornithostrongylinae. The genus is characterized by its synlophe consisting of oblique longitudinal ridges, mainly on the right side of the worms. ac]19840501