Systematic position of some nearctic Heligmosomoidea (Nematoda: Trichostrongylina) from the U.S. National Parasite collection and their description

The systematic position of some heligmosomoid nematodes from rodents, deposited in the U.S. National Parasite Collection (USNPC), is revised, mainly through the study of their synlophe, which in all cases was unknown or insufficiently described. The material was registered as different species of Longistriata Schulz, 1926, a genus whose representatives are only parasitic in Holarctic insectivores. Longistriata norvegica Dikmans, 1935, parasitic in Rattus sp. becomes a synonym of Hassalstrongylus aduncus (Chandler, 1932). Specimens registered as Longistriata dalrymplei Dikmans, 1935, from Ondatra zibethicus, are confirmed to belong to Carolinensis (Travassos, 1937). Specimens registered as Longistriata noviberiae Dikmans, 1935, parasitic in Sylvilagus floridanus alacer, were found to belong to Vexillata, and Vexillata noviberiae n. comb. is here proposed. This is the first record of a species of Vexillata in a lagomorph. Other specimens registered as Longistriata norvegica, parasitic in Geomys floridanus austrinus, were also found to be an undescribed species of Vexillata (Hall, 1916), which is named Vexillata chitwoodi n. sp. This is similar to Vexillata chabaudi Yoyotte-Vado, 1972, Vexillata petteri Durette-Desset, 1970, Vexillata scorzai Guerrero, 1984 and Vexillata tejerai Guerrero, 1984, all having the same number of cuticular ridges (4 dorsal, 5 ventral) and the division of the dorsal ray at its apex. The most related species is V. chabaudi, which is differentiated from the new species by rays 4 not curved distally, by thick rays 8, and by a dorsal ray enlarged at the level of the arising of rays 8.     

A new species of Vexillata (Nematoda: Trichostrongylina: Ornithostrongylidae) parasite of Heteromys desmarestianus (Rodentia: Heteromyidae) from Costa Rica

In July 1999, 2 heteromyid rodents Heteromys desmarestianus Gray, 1868, were collected from the Area de Conservación Guanacaste, Costa Rica, and examined for parasites. Individuals of a new species of Vexillata (Travassos, 1937) Durette-Desset, 1970, were found from the intestine of hosts. Vexillata brooksi n. sp. differs from all other congeners by the presence of spicules divided at the tip instead of simple spicules. The new species closely resembles Vexillata legallae Denke, 1977, and Vexillata convoluta (Caballero and Cerecero, 1943); however, it can be distinguished from both species by possessing a smaller number of cuticular ridges at the posterior part of the body in males (9 vs. 11 and 12, respectively) and by the absence of a carene at this level.     

Vexillata liomyos n. sp. (Nemata: Ornithostrongylidae) from Liomys pictus (Rodentia: Heteromyidae) from Mexico, with comments on the synlophe of Vexillata armandae.

Individuals of a new species of Vexillata were collected from the small intestines of Liomys pictus from the Estaci6n de Biología Chamela, in Jalisco State, Mexico. The new species shows an array of characters that allow us to recognize it as a member of Vexillata; however, it can be distinguished from other species of the genus in that males possess an asymmetrical caudal bursa, females possess a characteristic cuticular inflation at the level of the ovijector, and both sexes possess a synlophe with 9 ridges at the midbody. Additional detail of the synlophe of Vexillata armandae Gardner et al., 1994 from Chaetodipus hispidus in New Mexico shows that both sexes have 12 cuticular ridges just posterior to the cephalic inflation, and in the posterior region of the body, females have 9 ridges of equal size while males possess 11 equal-sized ridges. In both sexes, the carene disappears at the posterior end of the body.     

Phylogenetic relationships among species of Stilestrongylus Freitas, Lent and Almeida, 1937 (Trichostrongyloidea: Heligmonellidae: Nippostrongylinae), parasites of myomorph rodents (Rodentia: Muridae) in the Neotropics

The phylogenetic relationships of 14 species of Stilestrongylus were analyzed using the comparative morphology of 21 characters. We obtained 2 shortest trees of 50 steps, with a consistency index of 0.540 and 25 apomorphic character states. Ingroup monophyly was supported on these trees by 2 and 3 synapomorphies, respectively, and the ingroup was defined by the following characters: greater number of ventral ridges relative to the number of ridges dorsally, asymmetric bursa, and externodorsal rays differing in size. Sister-group relationships among Stilestrongylus and the other genera designated as outgroups are relatively consistent with those postulated by Durette-Desset's in a classification of the Nippostrongylinae. The ancestor of the species groups comprising Hassalstrongylus, Guerrerostrongylus, and Stilestrongylus originated and diversified in murids in the Neotropical region. Species of Hassalstrongylus occur in rodents between southeastern North America and the eastern part of South America (Brazil and Argentina), whereas species of Guerrerostrongylus and Stilestrongylus diversified exclusively in rodents in the Neotropics.     

Trichostrongylina (Nematoda) parasitic in Phyllotis sp. (Rodentia: Sigmodontinae) from Argentina, with description of three new species

The Trichostrongylina parasitic in the leaf-eared mouse Phyllotis sp. (Sigmodontinae) from the Province of Catamarca, Argentina are studied. Three new species of Stilestrongylus Freitas, Lent and Almeida, 1937 (Heligmosomoidea: Heligmonellidae: Nippostrongylinae) are described. Stilestrongylus andalgala n. sp. is distinguished from the most closely related species S. moreli Diaw, 1976 parasitic in Auliscomys boliviensis from Bolivia, by the absence of a common trunk of right rays 2 and 3, by left ray 4 shorter than ray 5, and by the shape of the female tail, without a mucron. Stilestrongylus catamarca n. sp. is distinguished from all the other species in the genus by hypertrophied rays 2, larger than rays 3, and from the closely related species Stilestrongylus barusi Durette-Desset, 1971, parasitic in Sigmodontomys alfari from Colombia, by right ray 4 longer than ray 5 and left ray 4 shorter than ray 5, by a larger spicule length/body length ratio (22.6% vs. 7.2%), and by the presence of a mucron on the female tail. Stilestrongylus gracielae n. sp. most closely resembles Stilestrongylus azarai Durette-Desset and Sutton, 1985, parasitic in Akodon azarae and in Graomys griseoflavus, and Stilestrongylus franciscanus Digiani and Durette-Desset, 2003, also parasitic in G. griseoflavus, both from Argentina. These latter differ from the new species by the right lobe of the caudal bursa: in S. azarai rays 4, 5 and 6 arise at same level from their common trunk and in S. franciscanus right rays 4 and 5 diverge at their distal extremity. Lamanema chavezi Becklund, 1963 (Molineoidea: Molineinae), a parasite of South American camelids, is reported in rodents for the second time.     

Two new species of Nippostrongylinae (Nematoda: Trichostrongylina: Heligmonellidae) from the grey leaf-eared mouse Graomys griseoflavus (Sigmodontinae) in Argentina

Two new species of Nippostrongylinae, Hassalstrongylus puntanus n. sp., and Stilestrongylus franciscanus n. sp. are described from the intestine of the grey leaf-eared mouse Graomys griseoflavus (Waterhouse, 1837) (Sigmodontinae) from the Province of San Luis, Argentina. Hassalstrongylus puntanus n. sp. is distinguished from the most closely related species H. dollfusi (Díaz-Ungría, 1963), a parasite of Mus musculus from Venezuela by longer rays 2, shorter rays 4, proximal half of the dorsal ray non-enlarged and a non-retractile female tail. Stilestrongylus franciscanus n. sp. is distinguished from the most closely related species S. flavescens Sutton & Durette-Desset, 1991, a parasite of Oryzomys flavescens from Argentina, by rays 2 and 3 diverging separately from common trunk of rays 2 to 6, and by right ray 3 arising from this trunk more distally than ray 6. Stilestrongylus azarai Durette-Desset & Sutton, 1985, a parasite of Akodon azarae from Buenos Aires, Argentina, was also found parasitizing G. griseoflavus, representing new host and locality records. Some additional morphological data for this species are also provided.     

2 new species of Stilestrongylus (Nematoda: Heligmonellidae) parasites of Peromyscus (Rodentia: Cricetidae) from Mexico

Stilestrongylus peromysci n. sp. collected from Peromyscus difficilis (Hidalgo state, México), differs from other species in the genus in number of the spines (30) in the synlophe (both sexes) and because the eighth ray arises from the root of the ninth ray; S. hidalguensis n. sp. parasitised Peromyscus sp. and differs from all other congeneric species in the presence of 24 spines in the male synlophe and in the arrangement of the bursal rays (2-2-1 in the right lobe and 2-3 in the left lobe). A key to the species of Stilestrongylus is provided.     

A new species of Tetrastemma (Nemertea: Enopla: Monostiliferoidea) from Ria de Foz, north-western Spain, found living in the mantle cavity of the bivalve mollusc Scrobicularia plana

A new species of monostiliferoidean nemertean, Tetrastemmafozensis , from the mantle cavity of the bivalve mollusc Scrobicularia plana , in the Ría de Foz, north-western Spain, is described and illustrated. Other nemerteans from the mantle cavity of Scrobicularia collected in Poole Harbour, southern England, are provisionally identified as conspecific with the Ria de Foz material, but show certain anatomical differences whose taxonomic significance cannot at present be assessed.     

The systematic position of some nippostrongyline nematodes (Trichostrongylina: Heligmosomoidea) parasitic in Argentinean sigmodontine rodents

The systematic position of two nippostrongyline nematodes described from Argentinean sigmodontine rodents is clarified. The first species, Hassalstrongylus multiovatus Suriano & Navone, 1992, parasitic in Akodon simulator Thomas from the province of Tucumán, was studied on the basis of type and voucher material. H. multiovatus is proposed as a junior synonym of Trichofreitasia lenti Sutton & Durette-Desset, 1991, a parasite described from Oligoryzomys flavescens (Waterhouse) in the province of Buenos Aires. The holotype and three of seven paratypes deposited as H. multiovatus were identified as T. lenti. One male paratype was identified as Guerrerostrongylus uruguayensis Sutton & Durette-Desset, 1991, a parasite described from O. flavescens in Uruguay. Three female paratypes were identified as Guerrerostrongylus sp. The second species, Stilestrongylus scapteromys Suriano & Navone, 1996, parasitic in Scapteromys aquaticus Thomas from the province of Buenos Aires, was studied on voucher material. Stilestrongylus scapteromys and Malvinema frederici Digiani, Sutton & Durette-Desset, 2003, the type-species of Malvinema Digiani, Sutton & Durette-Desset, 2003, were described from the same host and geographical region. As they are considered to refer to one and the same taxon, the new combination Malvinema scapteromys n. comb. is proposed for this species.     

Recent introduction of the dominant tunicate,Pyura praeputialis (Urochordata,Pyuridae) to Antofagasta,Chile

The large sessile tunicate Pyura stolonifera (Pleurogona: Stolibranchiata: Pyuridae), has been regarded as a complex taxon with disjointed distributions, including Australia (Pyura stolonifera praeputialis), South Africa (Pyura stolonifera stolonifera) and South America (Chile, Antofagasta: Pyura sp., the 'piure de Antofagasta'), and has been cited under at least five taxonomic combinations. The 'piure de Antofagasta' is a competitively dominant species in rocky intertidal habitats and shows a limited geographical range (60-70 km) exclusively inside the Bay of Antofagasta. Using cytochrome oxidase I (COI) mitochondrial sequence data from Pyura specimens of the three taxa we tested whether the Chilean taxon represents: (i) a Gondwana relict; (ii) a more recently divergent species; or (iii) a recently introduced species. The results suggest that the Chilean taxon is a recent introduction to Chile from Australian populations and that Pyura stolonifera praeputialis, from Australia, and the 'piure de Antofagasta' are geographical populations of a single species: Pyura praeputialis; whereas the South African taxon represents a second species: Pyura stolonifera.     

Cross-species utility of microsatellite markers in trichostrongyloid nematodes

The development of microsatellite markers for parasitic nematodes has been hampered by technical difficulties in isolation and PCR amplification. We have investigated the potential for circumventing these problems using microsatellites from 3 trichostrongyloid species on a panel of 7 species. Ten of the 22 PCR primer pairs tested amplified in species other than the target species, usually in closely related species, and 2 new variable loci were discovered in the sheep parasite Trichostrongylus vitrinus. This study provides evidence that cross-species testing of microsatellite primers can be an effective alternative to isolation de novo.     

Eight new species of Marasmodes (Asteraceae,Anthemideae) from South Africa

During a stay at the Kirstenbosch Research Centre in Cape Town (South Africa), several groups of Asteraceae were studied. One of these was the genus Marasmodes (tribe Anthemideae). After a careful taxonomic study of additional material, including the first species described by A. P. de Candolle, the author has concluded that eight collections should be considered as new species. These new species are described and their relationships with the most similar species of the genus are discussed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 330–342.     

DNA barcoding of fishes of Laguna de Bay, Philippines

Laguna de Bay, the largest lake in the Philippines, is an important part of the country's fisheries industry. It is also home to a number of endemic fishes including Gobiopterus lacustris (Herre 1927) of family Gobiidae, Leiopotherapon plumbeus (Kner 1864) of family Terapontidae, Zenarchopterus philippinus (Peters 1868) of family Hemiramphidae and Arius manillensis Valenciennes 1840 of family Ariidae. Over the years, a steady decline has been observed in the abundance and diversity of native fishes in the lake due to anthropogenic disturbances. In this study, a total of 71 specimens of 18 different species belonging to 18 genera, 16 families, and seven orders were DNA barcoded using the mitochondrial cytochrome c oxidase subunit I (COI) gene. All of the fish species were discriminated by their COI sequences and one endemic species G. lacustris, showing deep genetic divergence, was highlighted for further taxonomic investigation. Average Kimura 2-parameter genetic distances within species, family, and order were 1.33%, 18.91%, and 24.22%, respectively. These values show that COI divergence increases as taxa become less exclusive. All of the COI sequences obtained were grouped together according to their species designation in the Neighbor-joining tree that was constructed. This study demonstrated that DNA barcoding has great potential as a tool for fast and accurate species identification and also for highlighting species that warrant further taxonomic investigation.     

Abomasal parasites in wild sympatric cervids, red deer, Cervus elaphus and fallow deer, Dama dama, from three localities across central and western Spain: relationship to host density and park management

A survey of abomasal parasites in cervids from Central Spain was conducted at 3 sites, Quintos de Mora (Toledo), Malué?ez de Arriba (Cáceres), and La Herguijuela (Cáceres). Commonly occurring helminths belonged to 3 polymorphic species of the Ostertagiinae: Spiculopteragia asymmetricalS. quadrispiculata, Ostertagia leptospicularis/O. kolchida, and O. drozdzi/O. ryjikovi. Trichostrongylus axei was found in very few cases. Ostertagia drozdzi/O. ryjikovi and the minor male morphotype, S. quadrispiculata, are reported for the first time in red deer from Spain. The 3 ostertagiine species are also reported for the first time in fallow deer from Spain. These 3 species of Ostertagiinae are primarily parasites of cervids, and nematode species characteristic of domestic ruminants were not present. Prevalence of infection by gastrointestinal parasites in cervids was high, ranging from 97.5 to 100%, across the 3 areas sampled. Mean intensity of infection and abundance showed a positive relationship to the population density of red deer. Helminth burdens were higher in fallow deer than in the sympatric red deer and may reflect the gregarious social structure and different foraging patterns of fallow deer.     

Increasing numbers of bird species result from taxonomic progress,not taxonomic inflation

The impact and significance of modern taxonomy on other fields in biology have been subjects of much debate. It has been proposed that increasing numbers of vertebrate species are largely owing to ‘taxonomic inflation’. According to this hypothesis, newly recognized species result from reinterpretations of species limits based on phylogenetic species concepts (PSCs) rather than from new discoveries. Here, I examine 747 proposals to change the taxonomic rank of birds in the period 1950–2007. The trend to recognize more species of birds started at least two decades before the introduction of PSCs. Most (84.6%) newly recognized species were supported by new taxonomic data. Proposals to recognize more species resulted from application of all six major taxonomic criteria. Many newly recognized species (63.4%) were not based exclusively on PSC-based criteria (diagnosability, monophyly and exclusive coalescence of gene trees). Therefore, this study finds no empirical support for the idea that the increase in species is primarily epistemological rather than data-driven. This study shows that previous claims about the causes and effects of taxonomic inflation lack empirical support. I argue that a more appropriate term for the increase in species is ‘taxonomic progress’.     

Phylogeny of Philippine slender skinks (Scincidae: Brachymeles) reveals underestimated species diversity, complex biogeographical relationships, and cryptic patterns of lineage diversification

The spectacular, virtually endemic radiation of Philippine semi-fossorial skinks of the genus Brachymeles represent one of the few radiations of scincid lizards to possess both fully limbed and limbless species. And yet, nothing is known of the phylogenetic relationships of this exceptional group. Morphologically similar body plans have made it difficult to assess species-level diversity, and the genus has long been recognized as one of the more modest radiations of southeast Asian lizards. However, recent large-scale survey efforts have resulted in the discovery of numerous new species, and taxonomic studies indicate that the diversity within the genus Brachymeles is grossly underestimated. In this study we provide the first robust estimate of phylogenetic relationships within the genus Brachymeles using a multi-locus dataset and nearly complete taxonomic sampling. We provide statistical tests of monophyly for all polytypic species and two widespread limb-reduced species and our results indicate wholesale deviations from past summaries and taxonomic evaluations of the genus. With few exceptions, we are able to reject the monophyly of all polytypic and widespread species, thereby validating the need for large-scale taxonomic revisions. Our results reveal that the limbless, monotypic, genus Davewakeum is nested within Brachymeles. Mapping of body form on our preferred phylogenetic tree suggests that limb-reduction and digit loss has occurred on multiple occasions in the history of the genus. A Bayesian reconstruction of ancestral areas indicates strong statistical support for a minimum of five major dispersal events that have given rise to a major component of the observed species diversity on separate Pleistocene aggregate island platforms of the archipelago.     

Updated checklist and DNA barcode‐based species delimitations reveal taxonomic uncertainties among freshwater fishes from the mid‐north‐eastern Caatinga ecoregion,north‐eastern Brazil

The mid‐north‐eastern Caatinga is a semiarid freshwater ecoregion in North‐eastern Brazil that is dominated by temporary rivers and is currently classified as one of the least ichthyologically‐known ecoregions in the world. The present study aimed to provide an updated checklist of mid‐north‐eastern Caatinga ecoregion (MNCE) freshwater fish species and evaluate their taxonomic identity using morphology, DNA barcoding and multiple species delimitation approaches. After reviewing published studies and ichthyological collections, 119 species were identified. Among these were 94 putatively valid native and 14 non‐native species, five undescribed native species, four new records for the MNCE, 11 potential cases of misidentification and 14 species listed as inquirenda. Additionally, 252 individuals from 49 species were barcoded, revealing three potential taxonomic synonyms. The combined molecular approaches estimated a total of 91 native species, although a finalized species list for the MNCE awaits additional taxonomic revisions and field surveys. This study provides the most up‐to‐date species checklist for the MNCE and a molecular reference database for identifying MNCE fishes with DNA barcodes. Results highlight the need to integrate traditional taxonomy with molecular approaches to correctly identify species, especially in taxonomically problematic ecoregions such as the MNCE.