Ectoparasitism by Eutrombicula alfreddugesi larvae (Acari: Trombiculidae) on Liolaemus tenuis lizard in a Chilean fragmented temperate forest

We compared parasite load (prevalence and mean intensity) of Eutrombicula alfreddugesi larvae on the lizard Liolaemus tenuis sampled during January 2006 and 2007 from the interior and edges of large forest tracts in the coastal Maulino Forest (35 degrees 59'S, 72 degrees 41'W) and from nearby forest fragments (1.5-20 ha). All lizards were parasitized by chiggers regardless of location (prevalence, 100%); however, mean intensity of infestation was significantly lower at forest fragment edges compared with either large forest interiors or forest edges. We attribute differences in mean intensity to differences in microclimate among localities; maximum air temperature was significantly higher and relative humidity significantly lower in fragment edges compared with either large forest tract interior or edges.     

Sintopy of two Tropidurus lizard species (Squamata: Tropiduridae) in a rocky Cerrado habitat in central Brazil.

We studied the ecology of Tropidurus itambere and T. oreadicus that occur syntopically in rocky habitats of Cerrado vegetation in central Brazil during the dry season (April to September 2000). The two species are ecologically similar, but somewhat differentiated in vertical microhabitat use. The two species preferred rocky surface microhabitat. Both species demonstrated a unimodal activity pattern, with a peak between 10 and 15 h. Their diets were similar in composition and prey size. The most frequent item used by both species was ants, whereas the most important preys volumetrically were termites and ants. Small morphological differences observed between the two Tropidurus species could explain minor microhabitat divergence: T. itambere is slightly smaller, heavier, and more robust, and uses lower perches. T. oreadicus is larger, lankier, with longer extremities (tail, fore- and hindlegs), and uses a larger vertical microhabitat range. These ecological differences are slight, when compared with those observed between sympatric species of Tropidurus in spatially more heterogeneous landscapes. Considering the slight ecomorphological divergence between the two Tropidurus species and their high abundance in outcrops, we suggest that interspecific territoriality is the mechanism of coexistence.     

Pollination of four sympatric species ofAngelonia (Scrophulariaceae) by oil-collecting bees in NE. Brazil

The manner whereby the oil-producing bisaccate flowers ofAngelonia (Scrophulariaceae) are pollinated by female oil-collecting bees is reported for the first time. Observations were made in the Caatinga formation of Pernambuco, NE. Brazil, on four synchronopatric species. These differ in sizes and structural details of the corolla, level of flower exposition, and habitat preferences. All legitimate visitors wereCentris spp. (Anthophoridae):Angelonia hirta was mainly pollinated byC. fuscata andA. pubescens byC. hyptidis; A. bisaccata andA. hookeriana shared an unidentified species. Several exomalopsine, tetrapediine and meliponid bees exploit the flowers less descriminately for oil or pollen, respectively, without regularly contacting anthers and stigma. The flowers are protandrous, and are self-incompatible except those of the annualA. pubescens. After alighting, theCentris bees introduce their front legs simultaneously into each of the pouches and start alternate collecting movements to gather the oil from the trichome elaiophores. While doing so, they are forced by projections of the corolla floor to press their head under the anthers and stigma, whereby pollen is transferred with their frons or clypeus. On account of their collector type and behaviour,C. fuscata andC. spec. are not specialized toAngelonia but may equally exploit other nonrelated taxa for oil, whereasC. hyptidis exhibits oligolecty onA. pubescens. It possesses relatively elongate forelegs with padlike collectors suitable for sweeping the lipids from the scattered glandular hairs inside the divergent spurs of its host. It is the only species that also collects pollen (by buzzing) from the oil host.A. hirta and relatives, provided with dense elaiophore carpets, are, for their part, adapted to scrapingCentris species with typical oil collectors. Flower and bee phenologies, although largely dependent on the irregular rainfalls, are not always coincident.     

Cytogenetic divergence in two sympatric fish species of the genus Astyanax Baird and Girard, 1854 (Characiformes,Characidae) from northeastern Brazil

The fish genus Astyanax is widespread throughout the Neotropical region and is one of the most species-rich genera of the Characiformes. Cytogenetic studies of Astyanax have revealed marked intra- and interspecific diversity, with the identification of various species complexes. In this report, we describe the karyotypic structure of two sympatric species of Astyanax (Astyanax sp. and Astyanax aff. fasciatus) from the Middle Contas River basin in the northeastern Brazilian state of Bahia. Both species had 2n = 48 but differed in their karyotypic formulae. Small heterochromatic blocks and multiple nucleolar organizer regions (NORs) were identified in both species. Terminal CMA₃⁺/DAPI⁻ signals were observed in Astyanax sp. and A. aff. fasciatus, mostly coincident with NORs. These results show that chromosomal markers can be used to identify species in this fish complex. These markers can provide useful information for evolutionary studies and investigations on the mechanisms of chromosomal diversity in Astyanax.     

Pollination biology of four sympatric species of Habenaria (Orchidaceae: Orchidinae) from southern Brazil

The pollination process and breeding system of the sympatric Habenaria johannensis, H. macronectar, H. megapotamensis and H. montevidensis was documented for native populations from Rio Grande do Sul, Brazil. All species investigated offer a nectar reward (mean values of total sugars ranging from 18 to 26%) concealed in a spur. Habenaria montevidensis is pollinated by butterflies (Hesperiidae, especially of the genus Urbanus) that carry pollinaria on their eyes; the other three species are pollinated by Sphingidae. Habenaria johannensis is pollinated by the moths Manduca rustica and M. sexta that carry the pollinaria at the base of the proboscis. Habenaria macronectar is pollinated by the moths Eumorpha labrusca and M. cf. lucetius, and these bear pollinaria between the palpi. Habenaria megapotamensis is pollinated by moths of M. cf. lucetius that bear the pollinaria on the proboscis. All species studied are self‐compatible, but pollinator dependent. They also displayed high reproductive success (ranging from 69.48 to 97.40%) and male efficiency factors slightly higher than 1, suggesting that at least one flower was pollinated for each flower acting as pollen donor. At the study sites, the investigated Habenaria spp. are isolated (in terms of pollination) by a set of factors that includes differing floral morphologies, different pollinators and/or different pollinarium placement on the pollinator. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ??, ??–??.     

A new species of Pharyngodonidae (Nematoda) of Tropidurus torquatus (Squamata:Tropiduridae) from Brazil

Parapharyngodon bainae n. sp. (Nematoda:Pharyngodonidae) collected from the small intestine of Tropidurus torquatus (Squamata:Tropiduridae) is described. The new species is the 47 th species in the genus and the 14 th in the Neotropical region. The morphology of male posterior end, ovary position in females, and egg size can be used to differentiate P. bainae from the other congeneric species. Parapharyngodon rotundatus , Parapharyngodon sanisfaciecaudus , and Parapharyngodon riojensis are most closely related to P. bainae. In males of P. sanisfaciecaudus and P. rotundatus , the cloacal lip has a smooth appearance, whereas in P. bainae , males have an echinate cloacal lip. Parapharyngodon riojensis differs from P. bainae because its females have postbulbar ovaries, the eggs are larger, and the esophagi are larger in both sexes. Parapharyngodon spp. nematodes occupy an intermediate phylogenetic position among pharyngodonid parasite lineages in carnivorous and herbivorous reptiles. The average low intensity of infection for P. bainae (4.8 ± 4.6) is typically found in carnivorous reptiles. This fact and the high prevalence value (60%) can be explained by the ingestion of environmental substrata material containing parasite eggs while foraging.     

Patterns of trombiculid mite (Hannemania dunni) parasitism among plethodontid salamanders in the western Piedmont of North Carolina

Trombiculid mites are known to parasitize a variety of amphibian species, yet few comparisons of mite parasitism among amphibian species have been made. In this study, we investigated patterns of trombiculid mite parasitism among 3 plethodontid salamanders (Desmognathus fuscus, Eurycea cirrigera, and Plethodon cylindraceus) in the western Piedmont of North Carolina. All 3 salamander species were parasitized by a single species, Hannemania dunni. Desmognathus fuscus harbored mites more frequently (60.4% of individuals) than E. cirrigera (11.1%) or P. cylindraceus (14.6%). Desmognathus fuscus also had higher parasite loads than E. cirrigera or P. cylindraceus (P < 0.001). Mites on D. fuscus were found more frequently on the limbs than other body locations (P < 0.001). We found no correlation between salamander size and mite abundance (P = 0.689), but salamander collection sites influenced the abundance of mites on D. fuscus (P = 0.002). We found no effect of season on mite abundance in D. fuscus (P = 0.952). Salamander habitat preferences and edaphic or climatic differences among study sites may influence patterns of Hannemania sp. parasitism of salamanders.     

New species and sympatric relations of the chigger mite species group Talmiensis (Trombiculidae, Neotrombicula)

A revision of chigger mites species being closely related to Neotrombicula talmiensis (Schluger, 1955) has been performed. 2 new species are described: N. pontica sp. n. from Krasnodar Territory (Western Caucasus) and N. sympatrica sp. n. from Krasnodar Territory, Daghestan, Tuva, Armenia, Kirghizia and Turkey (Rize Province). N. pontica sp. n. is closely related to N. carpathica Schluger et Vysotzkaya, 1970 and differs from this species by the larger number of idiosomal setae (NDV = = 75-99 against 63-77), shorter legs (Ip = 782-847 against 844-920, TaIII = 67-74 against 70-80), lesser m-t (0.180 against 0.192), slightly lesser scutum and slightly longer setae. N. sympatrica sp. n. is closely related to N. carpathica and differs from this species by the longer scutal and idiosomal setae (PL = 67-78 against 57-69, H = 65-75 against 57-68, Dmin = 43-52 against 39-48, Dmax = 61-70 against 54-64), longer legs (Ip = 892-973 against 844-920, TaIII = = 77-86 against 70-80) and lesser m-t (0.168 against 0.192). N. carpathica is reported for the first time from Northern Caucasus (Karachai-Cherkess Republic, Kabardino-Balkaria, North Ossetia); N. talmiensis is reported for the first time from Khakasia. Data on joint occurrence of 3 species are reported. The 3 types of sympatric pairs of the species have been found in the Western Caucasus: 1) N. pontica sp. n. and N. sympatrica sp. n., 2) N. sympatrica sp. n., and N. carpathica, 3) N. pontica sp. n., and N. carpathica. Differences between species in that localities, where the joint occurrence was recorded, have been analysed. Sympatric relations between N. sympatrica sp. n. and N. carpathica are characterized by increased value of some general diagnostic characters of these species, such as the length of idiosomal setae and length of legs. Different characters play main distinguishing role in different sympatric localities. Besides that, some local features appear in certain species of sympatric pairs (narrow scutum in 3 samples of N. carpathica, numerous idiosomal setae in 1 sample of N. sympatrica), that differs the populations of the sympatric pair, and also discriminates such aberrant group from other material of the same species. Functions produced by the method of discriminant analysis are proposed for the purpose of diagnostics in talmiensis group. Tests for assumptions of discriminant analysis, such as normality and homogeneity of variances, has been performed beforehand. Verifications of the functions on test samples demonstrated the good quality of its working. Key to species using discriminant functions has been constructed.     

Pollination by fungus gnats in four species of the genus Mitella (Saxifragaceae)

The first example of pollination by fungus gnats in the eudicots is reported. The genus Mitella (Saxifragales) is characteristically produces minute, inconspicuous, mostly dull-coloured flowers with linear, sometimes pinnately branched, petals. To understand the function of these characteristic flowers, we studied the pollination biology of four Mitella species with different floral traits and different sexual expression: dioecious M. acerina , gynodioecious M. furusei var. subramosa , and hermaphroditic M. stylosa var. makinoi and M. integripetala. Flower-bagging experiments showed that wind pollination did not occur in the dioecious and gynodioecious species. Two years of observations of flower visitors at six study sites in Japan revealed that the principal pollinators of all four Mitella were specific species of fungus gnats (Mycetophilidae), which landed on the flowers with their long spiny legs settling on the petals. Characteristically, numerous pollen grains were attached to the fungus gnats in specific locations on the body. Although, on average, 1.3–2.6 fungus gnats visited each inflorescence per day, the fruit set of both bisexual and female flowers exceeded 63%. These results suggest that fungus gnats are highly efficient pollinators of Mitella spp., and that Mitella flowers are morphologically adapted to pollination by fungus gnats.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 449–460.     

A new species of Sinningia (Gesneriaceae) from northeastern Brazil

Sinningia nordestina is described and illustrated. Morphological and molecular characters are discussed. It is a new species endemic to northeastern Brazil and is distinguished from other members of the genus by its vestigial tubers, ascending pedicels with pendent flowers, small corollas, and deviating flowering period.     

Four new species of Erythroxylum (Erythroxylaceae) from northeastern Brazil

Erythroxylum simonis, E. pauferrense, E. bezerrae, andE. tianguanum from northeastern Brazil are described and illustrated, and their taxonomic and phytogeographic relationships are discussed.     

Ultrastructure of testes and spermatogenesis in the trombiculid mite,Hirsutiella zachvatkini (Schluger)

Summary

Spermatogenesis and sperm ultrastructure of the trombiculid mite Hirsutiella zachvatkini (Schluger 1948) have been investigated using transmission electron microscopy and compared with other arachnids studied. Sperm differentiation takes place in groups of synchronously developed germ cells of the two large sac-like paired testes. Each testis is composed of a secretory epithelium, which occupies their medio-ventral regions, and of a germinative epithelium situated in the latero-dorsal parts of testes together with large somatic cells. The germ cells are represented on sections by spermatogonia, spermatocytes, early, middle and late spermatids, and mature spermatozoa. Spermatocytes and spermatids contain two centrioles, which disappear afterwards, and a small Golgi-like structure forming an acrosomal cistema. Mature spermatozoa, which lie both within the meshes of somatic cells and also free in the lumen of testes, are compact oval aflagellate cells provided with peripheral channels. They also contain an acrosome, flattened between the cell membrane and the round electron-dense chromatin body, an oval body of lesser density lying in close proximity to the chromatin body, and a group of 5–7 mitochondria with spherically arranged cristae situated immediately behind the nuclear bodies. An acrosomal filament may be sometimes seen beneath the acrosome in the middle spermatids and disappears in the mature spermatozoa. These findings show that the mode of differentiation and pattern of organization of the male sex cells in trombiculid mites are of rather primitive type compared with other acarine spermatozoa.     

Speciation in sympatric species of land snails from the genus Trochulus (Gastropoda,Hygromiidae)

The identification and designation of land snail species in the genus Trochulus on the basis of shell characteristics are problematic because of their great phenotypic plasticity. Some genetic analyses have proved inconclusive, with much variation within populations and apparent gene flow among them. We examined this issue by morphometric and molecular approaches on the morphologically similar species T. coelomphala, T. hispidus and T. striolatus, co‐occurring in the Alpenvorland of Germany. While these species differed in shell and reproductive system morphology, there were forms that turned out intermediate in shell characters between T. coelomphala and T. hispidus but had genital morphology similar to T. coelomphala. Phylogenetic analysis, however, showed that these forms clustered neither with T. coelomphala nor T. hispidus but are sister to T. striolatus from the same region, which suggests that they evolved by way of sympatric speciation. Further, these analyses suggest that T. coelomphala diverged within T. hispidus; a crossing experiment indicated that they were interfertile. Expanding the study to include all available Trochulus sequences enabled us to infer evolutionary relationships between them and showed that T. hispidus is polyphyletic. Some Trochulus samples of one nominal species were grouped within others. The combination of phenotypic plasticity and possible mitochondrial DNA introgression illustrates the complex nature of evolutionary processes and the need for caution in the application of traditional taxonomic practice.     

Phylogenetic relationships of a new genus and species of microteiid lizard from the Atlantic forest of north-eastern Brazil (Squamata, Gymnophthalmidae)

A new genus and species of a short limbed and slightly elongate gymnophthalmid lizard is described from the Atlantic rain forests of north-eastern Brazil. The new genus is also characterized by short and stout pentadactyl limbs, presence of prefrontals, absence of frontoparietals, distinctive ear opening and eyelid, two pairs of genials, a distinct collar, smooth, quadrangular, dorsal scales, quadrangular ventrals, fused postfrontal and postorbital bones, and two pairs of sternal ribs. The geographical distribution of the new taxon extends from the state of Rio Grande do Norte to the northern bank of the Rio São Francisco in the state of Alagoas. All specimens were obtained in leaf litter, an observation which agrees with the fossorial habits suggested by the body shape and massive aspect of the head of this species. A phylogenetic analysis based on external morphology, osteology, and molecular data recovered the new lizard as the sister genus to Anotosaura , and Colobosauroides as the sister group to these two.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 543−557.     

A new species of Solanum subgenus Leptostemonum (Solanaceae) from northeastern Brazil

Solanum jabrense is apparently rare, and is only known from few collections in the Pico do Jabre of the state of Paraíba, Brazil. It is illustrated and its affinities with the informalErythrotrichum group are discussed.     

A new species of Miconia (Melastomataceae, Miconieae) from northeastern Brazil

Miconia caiuia occurs only in the highly endangered submontane moist forests in the states of Alagoas, Pernambuco, and northern Bahia, Brazil. It belongs to Miconia section Miconia subsection Secundiflorae. This new species can be distinguished from other species in this subsection by the lepidote-stellate trichomes on young branches, petioles, inflorescences and hypanthia, leaves with suprabasal nerves and wrinkled/auriculate bases, abaxial leaf surfaces with only sparse trichomes, a 5-locular ovary, and large mature fruits (10–13?×?12–15 mm) with up to 15 seeds, which are 2.5–3.5 mm long.     

Four new species of the mite genus Bakerdania (Heterostigmata, Pygmephoridae) from Russia

Four new mite species (Bakerdania palustris, B. taymyrica, B. mycophila, and B. littoralis) from different regions of Russia are described. Bakerdania palustris sp. n. is most similar to B. janetscheki Mahunka, 1970, differing in the presence of adjoining bases of setae ps ₂ and ps ₃ (in B. janetscheki, ps ₃ is separated from ps ₂) and also by shorter smooth setae 2b (in B. janetscheki, setae 2b are serrate and distinctly longer). Bakerdania taymyrica sp. n. is most similar to B. heisseli Mahunka, 1970, differing in the presence of the brush-like setae 1a (that are trichoid and serrate in B. heisseli); shorter setae tc′ on the tibiotarsus I, that are almost half as long as setae pl′ (in B. heisseli, tc′ is much longer, nearly as long as pl′). Bakerdania mycophila sp. n. is most similar to B. racki (Mahunka, 1967), differing in the presence of significantly longer ventral setae and the separate solenidion ω₁ (in B. racki, the latter is fused with the tibiotarsus). Bakerdania littoralis sp. n. is most similar to B. racki, differing from the latter in the shape of setae 1a, 2a, 3a, 3b, 4a that are basally thickened; in the shape of setae ps ₁ (trichoid in B. racki); and in the presence of the non-furcated setae 1b (in B. racki, these setae are bifurcate).