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Pictorial guide for valid species of Paracyatholaimus. Part 1, beginning. Simplified images of species come from the published descriptions: arcticus-Kreis, 1963; botosaneanui-Andrássy, 1973; chilensis-Gerlach, 1953b; diva-orig.; dubiosus-Meyl, 1954; duplicatus-Gerlach, 1964b; helicellus-Wieser, 1954a; intermedius-Gerlach, 1953a; lewisi-Coomans et al., 1985; occultus-Gerlach, 1956; paucipapillatus-Gerlach, 1955; pentodon-Riemann, 1966.
Source publication
Three new nematode species were found in the Angola Basin (south-east Atlantic Ocean) at depths of about 5500 m. Paracyatholaimus diva sp. nov. (Cyatholaimidae) is characterised by outer labial and cephalic setae of about 3–5 µm, multispiral amphidial fovea with six turns in males and four turns in females situated at the level of the dorsal tooth,...
Contexts in source publication
Context 1
... Salvador. 12 Paracyatholaimus pentodon Riemann, 1966. Riemann, 1966 Gerlach, 1967. Gerlach, 1967, Abb. 15 a-e; Red Sea. 19 Paracyatholaimus separatus Wieser, 1954. Wieser, 1954b, Abb. 12 a-c; Mediterranean. 20 Paracyatholaimus spinulosus Jensen, 1985. Jensen, 1985 fig. 7 A-F; Gulf of Mexico. 21 Paracyatholaimus ternus Wieser, 1954. Wieser, 1954a fig. 108 a-e; Chile. 22 Paracyatholaimus truncatus (Cobb, 1914 ). Cobb, 1914: 60-62, fig. 17 (=Cyatholaimus truncatus); Flor- ida, fresh or brackish water. Micoletzky, 1922: 377 (to subgenus Paracyatholaimus). Finding of Riemann (1970) in a similar habitat at the Caribbean coast of Colombia may be doubtful because of the lesser male body length ...
Context 2
... 1967, Abb. 15 a-e; Red Sea. 19 Paracyatholaimus separatus Wieser, 1954. Wieser, 1954b, Abb. 12 a-c; Mediterranean. 20 Paracyatholaimus spinulosus Jensen, 1985. Jensen, 1985 fig. 7 A-F; Gulf of Mexico. 21 Paracyatholaimus ternus Wieser, 1954. Wieser, 1954a fig. 108 a-e; Chile. 22 Paracyatholaimus truncatus (Cobb, 1914 ). Cobb, 1914: 60-62, fig. 17 (=Cyatholaimus truncatus); Flor- ida, fresh or brackish water. Micoletzky, 1922: 377 (to subgenus Paracyatholaimus). Finding of Riemann (1970) in a similar habitat at the Caribbean coast of Colombia may be doubtful because of the lesser male body length (1050 vs 1600 µm), strong conical inner labial papillae, other pattern of four ...
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Because of their relatively simple body plan, the number of morphological characters used to differentiate between closely related nematode genera is often limited. In addition, boundaries among genera sometimes become blurred due to the appearance of new trait combinations as more new species are described. Molecular phylogenetic analyses can addr...
Four new species of marine nematodes were collected from the continental shelf of the Potiguar Basin in northeastern Brazil. Zalonema vicentei sp. n. and Zalonema mariae sp. n. are characterized by having multispiral fovea amphidialis, lateral alae and ventral ala. These features also are found in Pseudochromadora, Desmodorella and Psammonema. They...
Citations
... Since then 31 species of this genus were described, but the majority of them have been transferred in Marylynnia Hopper, 1972 and Paracyatholaimus Stekhoven, 1950 genera, or declared species inquirendae (e.g. Tchesunov, 2008). The main problem of Longicyatholaimus is that likely these species are not abundant in the sediments and consequently the descriptions are based on few specimens and often only on females. ...
Longicyatholaimus maldivarum was a species erected by Gerlach in 1964 from specimens found in the Maldivian archipelago. Due to the finding of additional representatives of this species, L. maldivarum is re-described with the addition of new morphological details mainly about males, because the information about female in the original description are very scarce. The newly found specimens showed a total body length higher than in the type specimens (1936–2063 µm vs. 1330 µm long) as well as the ratio of the total body length divided by maximum body diameter (22–28 vs. 27). The multispiral amphideal fovea showed 5 turns vs. 4 turns and Gerlach did not notice the presence of sub-ventral teeth that were clearly observed in the present specimens. The copulatory apparatus that perfectly matched the Gerlach description showed a central lamella mainly visible under confocal microscopy. A slightly lower ratio of the spicule length divided by anal body diameter (1 vs. 1.4) and longer gubernaculum (25–32 vs. 25 µm long) were noticed as well. Pre-cloacal supplements appeared very interesting for the presence of stout and conical setae protruding from cup-shaped structures. Supplements were more than in type species (8–9 vs. 7). Also the tail revealed some differences with a lower ratio of its total length divided by anal body diameter 6 vs. 7–8. The current list of 15 valid species of the genus was reduced to 10 species. In detail, we considered Longicyatholaimus heterurus and Longicyatholaimus sp. 3 species inquirendae for the absence of male specimens in the original description. We also excluded L. filicaudatus and L. tenuicaudatus because they were considered species inquirendae by Wieser & Hopper (1967) and L. zosterae because it was transferred by Lorenzen (1972) to the genus Paralongicyatholaimus. The new morphological details observed for Longicyatholaimus maldivarum and the modified number of valid species of the genus required also a revision of the identification key.
... (Diagnosis (modified after Tchesunov, 2008 ): Paracanthonchinae . Lateral differentiation hardly developed. ...
... Paracyatholaimus was established by Micoletzky in 1922. Up to now, 30 species have been recorded worldwide (Gerlach and Riemann 1973; Platt and Warwick 1988; Tchesunov 2008). But, according to the review of this genus by Tchesunov (2008), only 23 of these species are valid. ...
... Up to now, 30 species have been recorded worldwide (Gerlach and Riemann 1973; Platt and Warwick 1988; Tchesunov 2008). But, according to the review of this genus by Tchesunov (2008), only 23 of these species are valid. A key for identification of the valid species including two new species is provided. ...
Two new free-living marine nematode species of Paracyatholaimus Micoletzky, 1923 Paracyatholaimus qingdaoensis sp. nov. and Paracyatholaimus huanghaiensis sp. nov. from the Yellow Sea, China are described. Paracyatholaimus qingdaoensis sp. nov. is characterized by cylindrical body with conical tail; spicules reverse S-shaped, distally pointed; gubernaculum plate, with two cusps at distal end, parallel to the spicules; 10 thick setose precloacal supplements in a 5 + 5 arrangement, anterior group of five supplements located at a protuberance. Paracyatholaimus huanghaiensis sp. nov. is characterized by a cylindrical body with conic-cylindrical tail; slender spicules curved, distally pointed; gubernaculum handle-shaped, expanding distally to a plate, with some sawteeth at distal end; three papillose precloacal supplements, each papilla protruding conically with cuticularized narrow ducts. A key for identification of species of Paracyatholaimus is proposed. http://www.zoobank.org/urn:lsid:zoobank.org:pub:0A8E40E5-AE7A-47DA-B755-61E1D088C1E9
... Malyutina et al., 2001; Gad, 2003; Mursch et al., 2008; Willen, 2008). One paper with descriptions of three new nematode species has been also published (Tchesunov, 2008). ...
The genus Acantholaimus (Chromadoridae: Nematoda) is one of the most species-rich deep-sea nematode genera. The descriptions of two new species and supplemental descriptions of five known species from the Angola Basin (south-east Atlantic Ocean) and a depth of about 5500 m are given. Acantholaimus formosus sp. nov. is characterized by a spindleshaped body with narrow elongated anterior end, the position of amphideal fovea on the apical tip of the body and by robust rugae and onchia. Acantholaimus skukinae sp. nov. is characterized by its cylindrical body shape; short outer labial, cephalic, cervical, and somatic setae; large amphideal fovea; the position of its amphideal fovea (situated relatively
far from the head end); and relatively small onchia. Acantholaimus angustus was previously found in the Peru Basin (central-eastern Pacific) and the Clarion–Clipperton Nodule Province (Equatorial Pacific), about 13,000 km apart from the nearest previous location of finding. The type location of A. verscheldi is the Kenyan coast of the Indian Ocean. New specimens of this species were found about 8000 km apart from the type location. Acantholaimus akvavitus, A. iubilus and A. quintus were previously found in different parts of the Atlantic and the Pacific.
Species of Pomponema have been reviewed and key for identification of Pomponema species has been provided. At the same time, one new species, Pomponema multisupplementa sp. nov. from the Yellow Sea is described. Pomponema multisupplementa sp. nov. is characterized by spindle body with lateral differentiation of three longitudinal rows of large dots; male head sensilla in the 6 + 6 pattern, four cephalic setae missing; females with four cephalic setae and their head sensilla in the 6 + 10 pattern; spiral amphidial fovea look like oval-shaped; pharynx with a oval posterior bulb; spicules curved with proximal cephalate and distal tapered; gubernaculum plate, hooked anteriorly, arcuate and parallel to spicule, without dorsocaudal apophysis; 72-76 tubular precloacal supplements; tail conical with distal third cylindrical.
Of 104 papers on nematodes published in Zootaxa from 2007 to 2012, seventy five, by 136 authors from 27 countries, described eight new genera and 155 new species. A bibliographic analysis of these papers and a list of new genera and species are presented in this paper.
Four new species of the genus Desmodora are described from the South Atlantic off the south-eastern coast of the State of Rio de Janeiro, Brazil. Desmodora porosum sp. nov. is characterized by sexual dimorphism in the shape of the amphids, which are closed loop-shaped in males, and multispiral amphids in females. A case of intersexuality was found in the species, with a functional female gonad. Desmodora profundum sp. nov. is characterized by filiform spicules with a capitulum, buccal cavity with one dorsal and one small ventral tooth, tail cylindrical with a terminal spinneret, and wider rings in the neck region than on the rest of the body. Desmodora veronicae sp. nov. possesses cryptospiral amphids, a buccal cavity with one dorsal tooth and two smaller ventral teeth, 14 tubular pre-cloacal supplements, two ventral cuticular protruberances on the tail, and curved spicules with a capitulum and velum. Desmodora curvatum sp. nov. has the cuticle finely striated, without somatic setae, multispiral amphids, and a gubernaculum without apophysis, curved dorsally with the tip directed toward the end of the body.
