Neyraiella distinctus n. sp. (Oxyurida, Blattophilidae) parasite of nymphs of Gryllodes laplatae sauss (Orthoptera, Gryllidae) in Argentina

Neyraiella distinctus n. sp. was found parasitizing nymphs of the cricket Gryllodes laplatae Sauss in City Bell, Argentina. This species was characterized by having the excretory pore in the posterior end of the basal bulb, vulva protruding with one lip well developed in the 1/3 end of the body, anus of the female with wings, male with a single spicule without any sculpture, gubernaculum and bursa are absent, six pairs of genital papillae arranged in two preanal pairs, one adanal pair and three postanal pairs, and the tail appendage in both sexes was short and conic

A new species of Hammerschmidtiella Chitwood, 1932 (Nematoda, Thelastomatidae) parasite of the brown cockroach Periplaneta brunnea Burmeister, 1838 (Blattodea, Blattidae) from Argentina

A new species of the genus Hammerschmidtiella, H. eltalaensis sp. nov. parasitizing a brown cockroach Periplaneta brunnea Burmeister from El Tala river, Catamarca, Argentina, is described and illustrated. It is characterized by having the cuticle striated, without lateral alae, mouth with three toothed lips and eight labial papillae, amphids small and pore shaped, buccal capsule short, wide, with four mobile teeth, oesophagus with metacorpus valvate, isthmus cylindrical and thin surrounded by nerve ring, and a rounded basal bulb heavily muscled and valvate, the vulva is slightly protruding and lies in the anterior third of the body, didelphic, prodelphic, eggs small and elongate, the male with one spicule, without gubernaculum, the genital papillae arranged in one pair of small preanal papillae, and two postanal papillae, one pair is the base of the tail appendage. Tail appendage very long, thin, and reaching almost one third of the length of the body in the female. In the male the posterior end of the body abruptly truncated posterior to anus with spine-like long tail appendage.Centro de Estudios Parasitológicos y de Vectore

South American species of Paragordius Camerano, 1897 (Gordiida, Nematomorpha), with redescription of Paragordius minusculus and a description of a new species

Paragordius is a genus of Gordiida with a worldwide distribution, but with a scarce specific diversity. Sixteen species of the genus Paragordius have been described so far. In many cases, as with the other genera of Gordiida, the original descriptions of the species are insufficient due to the limitations of the techniques employed. In this work the holotypes of P. minusculus and P. esavianus are redescribed by scanning electron microscopy (SEM), a new species of Paragordius is described, the distribution for P. esavianus and P. varius is enlarged and a new host record of P. esavianus is presented.Facultad de Ciencias Naturales y Muse

Interactive effects of ocean acidification and ocean warming on Pacific herring (Clupea pallasi) early life stages

The synergy of ocean acidification and ocean warming may lead to negative effects in marine organism responses that would be absent under single stressors. While adult fish are effective acid-base regulators, early life stages may be more susceptible to environmental stressors. Pacific herring are ecologically and economically important forage fish native to the U.S. Pacific Northwest (PNW), and several herring populations in the PNW have experienced reductions in stock abundance. Studies to date have focused on Atlantic herring, and little is known about the response of Pacific herring to ocean acidification and warming. Therefore, this study focused on the combined effects of ocean acidification and warming on Pacific herring early life stages. We incubated Pacific herring embryos under a factorial design of two temperature (10°C, 16°C) and two pCO2 (600 µatm, 1200 µatm) treatments from fertilization until hatch (11 to 15 days depending on temperature). Elevated pCO2 was associated with a small increase in embryo mortality. However, elevated temperature was associated with greater embryo mortality, greater embryo heart rates and yolk areas upon hatch, lower percent normal hatch, and decreased larval lengths. The interaction of elevated temperature and pCO2 was associated greater embryo respiration rates and yolk areas. This study indicates that temperature will likely be the primary global change stressor affecting Pacific herring embryology, and interactive effects with pCO2 may introduce additional challenges

A new species of Protrellus Cobb, 1920 (Nematoda, Thelastomatidae) parasite of the field cockroach Blatella vaga Hebard, 1919 (Blattodea, Blattidae) from Catamarca, Argentina

A new species of the genus Protrellus, P. blatta sp. nov. parasitizing a field cockroach Blatella vaga Hebard, 1919, from El Tala river, Catamarca, Argentina, is described and illustrated. It is characterized by having the mouth opening circular, the buccal capsule with eight very small teeth, the nerve ring around oesophageal corpus, the excretory pore anterior to vulva, the vulva anterior to base of oesophagus, didelphic, the posterior ovary reflexed anterior to rectum, about one third of a body length from posterior end, the egg ellipsoidal, colourless, bearing a lateral cuticular crest, tail conical, with long filiform projection, the male with testis single, outstretched, one spicule, very small, short and straight, gubernaculums absent, the genital papillae arranged in three pairs of ventrolateral papillae, of which the first pair are close together and preanal position, two pairs postanal, tail conical and short, less than one twentieth of total body. A taxonomic key of Protrellus species is given.Centro de Estudios Parasitológicos y de Vectore

Neyraiella distinctus n. sp. (Oxyurida, Blattophilidae) parasite of nymphs of Gryllodes laplatae sauss (Orthoptera, Gryllidae) in Argentina

Neyraiella distinctus n. sp. was found parasitizing nymphs of the cricket Gryllodes laplatae Sauss in City Bell, Argentina. This species was characterized by having the excretory pore in the posterior end of the basal bulb, vulva protruding with one lip well developed in the 1/3 end of the body, anus of the female with wings, male with a single spicule without any sculpture, gubernaculum and bursa are absent, six pairs of genital papillae arranged in two preanal pairs, one adanal pair and three postanal pairs, and the tail appendage in both sexes was short and conic.Facultad de Ciencias Naturales y Muse

South American species of Paragordius Camerano, 1897 (Gordiida, Nematomorpha), with redescription of Paragordius minusculus and a description of a new species

Paragordius is a genus of Gordiida with a worldwide distribution, but with a scarce specific diversity. Sixteen species of the genus Paragordius have been described so far. In many cases, as with the other genera of Gordiida, the original descriptions of the species are insufficient due to the limitations of the techniques employed. In this work the holotypes of P. minusculus and P. esavianus are redescribed by scanning electron microscopy (SEM), a new species of Paragordius is described, the distribution for P. esavianus and P. varius is enlarged and a new host record of P. esavianus is presented.Facultad de Ciencias Naturales y Muse