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1.
Ecological opportunity is often proposed as a driver of accelerated diversification, but evidence has been largely derived from either contemporary island radiations or the fossil record. Here, we investigate the potential influence of ecological opportunity on a transcontinental radiation of South American freshwater fishes. We generate a species‐dense, time‐calibrated molecular phylogeny for the suckermouth armored catfish subfamily Hypostominae, with a focus on the species‐rich and geographically widespread genus Hypostomus. We use the resulting chronogram to estimate ancestral geographical ranges, infer historical rates of cladogenesis and diversification in habitat and body size and shape, and test the hypothesis that invasions of previously unoccupied river drainages accelerated evolution and contributed to adaptive radiation. Both the subfamily Hypostominae and the included genus Hypostomus originated in the Amazon/Orinoco ecoregion. Hypostomus subsequently dispersed throughout tropical South America east of the Andes Mountains. Consequent to invasion of the peripheral, low‐diversity Paraná River basin in southeastern Brazil approximately 12.5 Mya, Paraná lineages of Hypostomus, experienced increased rates of cladogenesis and ecological and morphological diversification. Contemporary lineages of Paraná Hypostomus are less species rich but more phenotypically diverse than their congeners elsewhere. Accelerated speciation and morphological diversification rates within Paraná basin Hypostomus are consistent with adaptive radiation. The geographical remoteness of the Paraná River basin, its recent history of marine incursion, and its continuing exclusion of many species that are widespread in other tropical South American rivers suggest that ecological opportunity played an important role in facilitating the observed accelerations in diversification.  相似文献   

2.
《Comptes rendus biologies》2019,342(5-6):230-235
Discocyrtoides pinorum sp. nov. is described from the conifers forest in Paraná State, Southern Brazil. This is the second species of Discocyrtoides Mello-Leitão, 1923, the other being known from São Paulo State. It is remarkable for having greenish/yellowish spots in the dorsal scutum highly contrasting with the brown background, a feature rare in Mitobatinae, hitherto known only for Ruschia Mello-Leitão, 1940. It is the first record of this genus for Paraná State (WWF Ecoregion NT0101, Araucaria moist forests). Terminology for the male genitalia of the Mitobatinae is defined and illustrated.  相似文献   

3.
A new species of the isoetalean leaf genus Lepidophylloides is described. This Guadalupian species from the Paraná Basin, Lepidophylloides corumbataensis, found as silicified microphylls in the Corumbataí Formation in the municipality of Piracicaba, São Paulo state, in southern Brazil, is the first species of the genus to be formally described for Brazil, and possibly the first for Gondwanaland. This is also the first time that surviving palisade tissue has been found in a species of Lepidophylloides. The new species is compared to known species and shown to be distinct from all previously described from Euramerican and Cathaysian floras. The organization of the xylem in arch-like or crescent-shaped bundles suggests a relation to Cathaysian species. The close association with Lycopodiopsis derbyi stems (which have true leaf scars and must have suffered leaf abscission) suggests that they are different organs from the same species.  相似文献   

4.
Mejdalani G  Silva RS  Garcia C 《ZooKeys》2011,(160):59-71
Tacora johanni, a new species from Rondônia State, North Brazil, is described and illustrated. The new species can be recognized by the male genital features, especially the subgenital plates with the basal half distinctly expanded and with outer lateral margin round, the long and slender preapical pygofer process, and the styles with apical half strongly curved. Also, the genus is recorded for the first time from Venezuela, based on specimens of Tacora saturata Young, 1977, while the female of this species (here described in detail for the first time) shows two unusual features of the genitalia. A key to males of all known Tacora species and a map showing the known distribution of the genus are provided.  相似文献   

5.
A new species of Eigenmannia is described from the Rio Paraná (the Grande, Paranapanema and Tietê basins). This new species is distinguished from all congeners by colouration pattern, position of the mouth, relative depth of posterodorsal expansion on infraorbitals 1 + 2, number of teeth, osteological features, number of rows of scales above lateral line (LL) and morphometric data. Comments on the widened cephalic lateral-line canals of Sternopygidae and a dichotomous key to the species of Eigenmannia from the Rio Paraná Basin are provided.  相似文献   

6.
Evidence for the extinction of the bumblebee Bombus bellicosus in Paraná state, in Brazil, is presented. The species is found in areas covered with open grass fields and shrub vegetation, originally ranging from northwestern Argentina to Paraná, where it reached its northeastern limit. Until the early 1980s, B. bellicosus was relatively abundant in Paraná, when the last known specimens were collected. In recent surveys conducted from 2002 to 2005, no specimens were recovered at sites in which the species was previously known to occur. Possible causes for local extinction of this species are discussed, including habitat conversion, pollution and climate change.  相似文献   

7.
Lorilichus n. g. (Pterolichidae, Pterolichinae) is restricted to the Indo-Australian parrots of the family Loriidae. Assigned to this new genus are Pterolichus (Pseudalloptes) species described by Trouessart in 1884, namely, lobiger (type-species), delibativentris, discifer, cultriventris, emargiventris and securiventris. The first three named species are illustrated and two new species, parvifolius and grandifolius, are described: the five species are from Lorius domicellus (L.).  相似文献   

8.
Records of sympatry between Alouatta caraya and A. clamitans are rare despite their extensive range overlap. An example of their current sympatry and the rediscovery of free-ranging potential hybrids of A. caraya and A. clamitans in the forests of the Upper Paraná River, Southern Brazil, are reported in this paper. Eight groups were observed in the study area: five monospecific groups of A. caraya, two of A. clamitans, and a group containing two adult males and two adult females of A. caraya and a sub-adult male and two adult females identified as Alouatta sp. The color of the last three individuals was a mosaic between the two species; this is consistent with previously described variations in museum specimens collected in the Paraná River in the 1940s that had been identified as potential hybrids. The results from this study emphasize the need for scientific studies in the region of the Ilha Grande National Park, one of the few regions in the Paraná River that currently harbors both howler species. Contribution number 1637 of the Departamento de Zoologia, Universidade Federal do Paraná, Caixa Postal 19020, 81531-980, Curitiba, Paraná, Brasil.  相似文献   

9.
The generic diagnosis of Parancylodiscoides Caballero y C. & Bravo-Hollis, 1961 (Monogenoidea: Dactylogyridae), with three valid species, was amended to include dactylogyrids having: a haptor with dorsal and ventral anchor/bar complexes, 14 hooks (seven pairs) and four reservoirs (two pairs); a dorsal bar with bifurcate ends; hooks with protruding, blunt and slightly depressed thumbs and undilated shanks; a dextroventral vaginal aperture leading to an elongate and oblique vaginal vestibule; a germarium dextral to the testis; a vas deferens looping the left intestinal caecum; a copulatory complex lacking an accessory piece; and two intestinal caeca lacking diverticula and united posterior to the gonads. Parancylodiscoides is most similar to Sundatrema Lim & Gibson, 2009, from which it differs only by the position of the vaginal aperture (sinistroventral in Sundatrema spp.) and by lacking a sucker-like genital pore. New information concerning the number and distribution of haptoral hooks, the relative positions of the gonads and the course of the vas deferens was provided for the type-species, P. chaetodipteri Caballero y C. & Bravo-Hollis, 1961. Parancylodiscoides longiphallus (MacCallum, 1915) Lim & Gibson, 2009 was redescribed based on specimens collected from the Atlantic spadefish Chaetodipterus faber from the Gulf of Mexico off Mississippi and Guaratuba Bay, Paraná, Brazil; its occurrence on the Atlantic spadefish from the Gulf of Mexico, Guaratuba Bay and off Puerto Rico represented new geographical records for this helminth. Parancylodiscoides caballerobravorum Cezar, Luque & Amato, 1999 was considered a junior subjective synonym of P. longiphallus. The monotypic Isohaliotrema Young, 1968 was placed in synonymy with Parancylodiscoides and its type-species, I. platacis Young, 1968, transferred to Parancylodiscoides as Parancylodiscoides platacis (Young, 1968) n. comb.  相似文献   

10.
On the consideration of the morphological characters of its type-species, especially the shape and structure of the aedeagus, the genus Tosevskiana Pavicevic, 1985, is removed from the subfamily Pachydeminae, in which it was originally described, to the subfamily Melolonthinae. The new combination Tosevskiana sithoniensis (Král, 1998) comb. n. is also proposed. Thus, the genus Tosevskiana is now composed of two species localized in the south east of the Balkan Peninsula. In addition, the restoration of the combination Rhizotrogus camusi Antoine, 1959, is based on the examination of the genital segment of the type-specimen.  相似文献   

11.
12.
Abstract

The 20 described species of diurnal moths previously in Simaethis auct. (not Leach, 1815) in New Zealand are transferred to Asterivora n.gen. The genus is described and distinguished from other genera in Choreutidae; genitalia of the type-species are figured. Asterivora oleariae, a new species associated with Olearia lyalli Hook.f. (Asteraceae: Compositae) from The Snares and Stewart Island, is described.  相似文献   

13.
The aim of the present contribution is to describe a partial fossil skull belonging to the catfish genus Sorubim. The specimen originates from the Late Miocene Ituzaingó Formation, at Paraná locality, Entre Ríos Province, Argentina. The material described here (MACN Pv-14224) was determined just to genus because the living species of Sorubim are morphologically similar. Presence of Sorubim is in concordance with the hypothesis indicating that most extant pimelodid genera were already present by the Late Miocene. Present finding constitutes the first fossil record for the genus.  相似文献   

14.
15.

The Crenicichla mandelburgeri species complex from the Middle Paraná shows parallel evolution of ecomorphs to the unrelated C. missioneira species complex from the Uruguay River. In this article, we describe a new species from the C. mandelburgeri species complex that has evolved a parallel morphology and ecology to an unrelated species from the C. missioneira species complex (C. celidochilus). The new species is a pelagic predator that feeds predominantly on fishes and together with C. celidochilus is the only known pelagic species in the large riverine genus Crenicichla. The new species is endemic solely to a small tributary (the Urugua-í) of the Middle Paraná River where it is sympatric and partly syntopic with two other closely related endemic species that, however, differ strongly in their ecomorphologies (one is a generalistic invertivore and the other a specialized molluscivore). Mitochondrial DNA phylogeny finds the new species nested within the widespread C. mandelburgeri. Reduced genome-representation ddRAD analyses, however, demonstrate that this new species is of a hybrid origin and shares ancestry with C. ypo, one of the two studied sympatric species.

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16.
Aim To elucidate the role of vicariance versus dispersal at the microevolutionary scale in annual killifish populations belonging to the Austrolebias bellottii species complex (Rivulidae). Within this complex, A. bellottii and A. apaii have low vagility and occur widely within the study area, making them excellent models for testing biogeographic hypotheses of differentiation. Location South America, in the Paraná–Uruguay–La Plata river basin. Methods Molecular data and morphometric analyses were used to reconstruct the phylogeographic history and morphological variation of 24 populations of two taxa of the A. bellottii species complex. Phylogenetic analyses using maximum likelihood (ML) and Bayesian inference (BI) model‐based methods, estimates of clade divergence times implemented in beast , non‐metric multidimensional scaling, analysis of molecular variance results, and morphological analyses elucidated the role of vicariance versus dispersal hypotheses in population differentiation in the aforementioned river basin. Results In the A. bellottii species complex from the Paraná–Uruguay–La Plata river basin, past allopatric fragmentation from vicariance events seems to be the most plausible scenario for diversification since the Late Miocene and more recently since the Plio‐Pleistocene. The Plio‐Pleistocene vicariance produced the differentiation of three major clades in A. bellottii populations. One clade from the eastern Uruguay River drainage was separated from another in western Uruguay and the Paraná–La Plata River drainages. A later vicariance event split populations to the south (lower Paraná–La Plata Basin) and north (middle Paraná) of the western Paraná River drainage. However, our results do not exclude the possibility of dispersal events among A. bellottii populations from both the Uruguay and Paraná river drainages, which could occur in these river basins during hypothesized connectivity cycles of the Late Pliocene and Pleistocene. Main conclusions Past allopatric fragmentation caused by different vicariance events seems to be the main driver of diversification in the A. bellottii species complex since the Plio‐Pleistocene. However, the current molecular data suggest that populations from both drainages of the Paraná–Uruguay rivers may have experienced cycles of connectivity during the Pleistocene, perhaps including multiple vicariance or dispersal events from populations located in the western lower Uruguay River drainage, which encompassed climatic and geological changes in the Paraná–Uruguay–La Plata Basin.  相似文献   

17.
Clestobothrium gibsoni n. sp. is described from the intestine of the bullseye grenadier Bathygadus macrops (Macrouridae) collected in the northeastern Gulf of Mexico. The new species can be distinguished from both C. crassiceps (Rudolphi, 1819), the type-species of the genus, and C. neglectum (Lönnberg, 1893), the second species in the genus, by its unique ovary, which is transversely elongate and tapered on both ends rather than being U-or H-shaped, and by having more testes (60-65 vs 40-50 and 35-45 per proglottid). The new species is also compared to Bothriocephalus acheilognathi Yamaguti, 1934 and B. kivuensis Baer & Fain, 1954, two species with similar scoleces which have previously been assigned to Clestobothrium . The generic diagnosis of Clestobothrium is amended to include species with either anoperculate or operculate eggs. This is the first report of an adult tapeworm from a species of Bathygadus , and the first report of a species of Clestobothrium Lühe, 1899 (Bothriocephalidae) from the Gulf of Mexico.  相似文献   

18.
19.
The sharpshooter genus Geitogonalia Young was so far known from a single species from Southeastern Brasil—Geitogonalia quatuordecimmaculata (Taschenberg). A new species, Geitogonalia viridis, is described and illustrated in this paper based on males and females from the state of Rio de Janeiro. In addition, the female of G. quatuordecimmaculata is for the first time described and illustrated in detail. Geitogonalia quatuordecimmaculata is a dark species marked with bright orange on the fore wings, whereas the new species has the corium and clavus of the fore wings mostly green. The paraphyses are well developed in G. quatuordecimmaculata, with elongate rami, whereas they are inconspicuous in G. viridis, with the rami modified as a pair of very small sclerites.  相似文献   

20.
Two new species of Coronigoniella Young are described and illustrated: C. osborni, sp. n., from SE. and S. Brazil (Espírito Santo, Minas Gerais, Rio de Janeiro, and Paraná states), and C. formosa, sp. n., from central W. and SE. Brazil (Goiás and Minas Gerais states, and the Distrito Federal). The presence of a sclerotized plate from the abdominal sternum VIII is reported in females of Coronigoniella for the first time. Taxonomic and morphological notes are given for C. spinosa (Osborn) based on specimens from its type-locality in Mato Grosso State. Tettigonia ruficaput (Walker), a species from Colombia previously considered of uncertain taxonomic position, is transferred to Coronigoniella. Possible host plants of C. osborni, sp. n. are Coleus sp. (Lamiaceae), Symphytum sp. (Boraginaceae), and Vernonia sp. (Asteraceae). The genus Coronigoniella is newly recorded from Alagoas, Bahia, Espírito Santo, Goiás, Minas Gerais, Paraná, and São Paulo states, as well as from the Distrito Federal, Brazil. A map showing the known geographic distribution of the two new species is presented. Resumo Duas novas espécies de Coronigoniella Young são descritas e ilustradas: C. osborni, sp. n., do sudeste e sul do Brasil (estados do Espírito Santo, Minas Gerais, Rio de Janeiro e Paraná), e C. formosa, sp. n., do centro-oeste e sudeste do Brasil (estados de Goiás e Minas Gerais, assim como o Distrito Federal). A presença de uma placa esclerosada do esterno abdominal VIII é registrada em fêmeas de Coronigoniella pela primeira vez. Notas taxonômicas e morfológicas sobre C. spinosa (Osborn) são fornecidas, com base em espécimes provenientes da sua localidade-tipo no Estado do Mato Grosso. Tettigonia ruficaput (Walker), uma espécie da Colômbia anteriormente considerada como de posição taxonômica incerta, é transferida para Coronigoniella. Coleus sp. (Lamiaceae), Symphytum sp. (Boraginaceae) e Vernonia sp. (Asteraceae) são possíveis plantas hospedeiras de C. osborni, sp. n. O gênero Coronigoniella é pela primeira vez registrado nos estados de Alagoas, Bahia, Espírito Santo, Goiás, Minas Gerais, Paraná e São Paulo, assim como no Distrito Federal, Brasil. Um mapa mostrando a distribuição geográfica conhecida das duas novas espécies é apresentado.  相似文献   

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