RESUMO
A new free-living marine nematode of the family Xyalidae is described from Armação Beach, northeastern Brazil, and the genus Pseudosteineria is reviewed. Pseudosteineria longisetis sp. n. is characterized by having six groups of long subcephalic setae, amphids situated slightly anterior to the groups of subcephalic setae or at the level of the first subcephalic setae, long somatic setae located posteriorly to subcephalic setae and distributed along the body, one papiliform precloacal supplement, and gubernaculum with dorso-caudal apophysis. An emended diagnosis of the genus, an updated list of species and dichotomous identification key, and a pictorial key are given. A comparative table including the main characters of all Pseudosteineria species is also provided.
Assuntos
Cromadoria , Nematoides , Animais , BrasilRESUMO
A new species of free-living marine nematode is described from Itapuã beach, northeast of Brazil. Pomponema veronicae sp. n. differs from other species of Pomponema by having buccal cavity with large pointed dorsal tooth, two subventral teeth and pairs of denticles, gubernaculum with two L-shaped lateral plates and having a membrane at its distal end that connects to L-shaped plate, and presence of a ventral orifice at distal end of L-shaped plates. It also differs from other species in the size of spicules and gubernaculum. The new species is considered most closely related to Parapomponema species because of the L-shaped lateral plates of gubernaculum, but the taxonomic status of Parapomponema was reviewed and Parapomponema and Propomponema are now synonymized with Pomponema. Pomponema cyatholaimoides is considered as a species inquirendum and Pomponema carinatum is accepted as Pomponema loticum. An updated identification key to species of Pomponema is included.
Assuntos
Nematoides , Animais , Brasil , CromadoriaRESUMO
One new species of Parasphaerolaimus is described from a Brazilian estuarine system with intra-uterine development of its offspring. Parasphaerolaimus magdolnae sp. n. is distinguished from other species of the genus by the presence of only one anterior testis, spicules morphology and size and a gubernaculum without dorsal apophysis. The cuticle of the new species is striated and the position of the vulva is far posterior on the body, almost reaching the anus. The taxonomy of Parasphaerolaimus was also re-examined and two other species were transferred from Sphaerolaimus to Parasphaerolaimus after the last revision: P. pentasetus (Pastor de Ward, 1984) comb. n. and P. striatus (Allgén, 1935) comb. n. An updated identification key for all valid species of Parasphaerolaimus is included.
Assuntos
Nematoides , Animais , Brasil , Cromadoria , Feminino , MasculinoRESUMO
New records of nematode species in Brazil, which appeared after or were not mentioned in the last review, are shown in this paper. All environments were considered, including the continental margin. In addition, all studies on marine nematodes in Brazil, including grey literature, ecological papers and book chapters, are listed. Furthermore, information on genera/species richness, dominant genera, and densities is also presented. A total of 11 orders, 72 families, 372 genera, and 450 species of nematodes were recorded in Brazilian marine environments by April 2017. Following problems are discussed: taxonomic lists available only in grey literature, use of outdated identification keys (leading to incorrect identifications), and identifications mostly to putative species or to the genus level.