Comparative study on the forefoot and hindfoot intrinsic muscles of some cavioidea rodents (Mammalia, Rodentia)

The present study compares the forefoot and hindfoot musculature of five representative species of Cavioidea rodents. In all species, the musculature of both forefeet and hindfeet have the same array regardless of the absence of digit I in the manus of Hydrochaeris hydrochaeris and Cavia porcellus. Our results suggest a tendency in these species towards a three-digit system, with a functional loss of digit V and a predominance of digit III in their forefeet. In the same way, the muscular reduction of digit I in the other rodents analyzed indicates a four-digit system with predominance of digit II in Myoprocta acouchy and Dasyprocta leporina and of digit V in Agouti paca. There seems to be an association between the muscular arrangement and functional axis of the foot, raising the general question why this axis runs between the third and forth digit, or along the third digit.     

A survey of hemoparasite infections in free-ranging mammals and reptiles in French Guiana

Blood smears of 1,353 free-ranging mammals (35 species) and 112 reptiles (31 species) from French Guiana were examined for hemoparasites. Parasites from 3 major groups were recorded: Apicomplexa (including hemogregarines, piroplasms, and Plasmodium spp.), Trypanosomatidae, and Filaroidea. Fifty percent of the individuals (86% of the species) were infected by parasites from at least 1 group. Hemogregarines, identified as Hepatozoon sp., infected numerous snakes with high prevalences (30-100%); infection is reported for the first time in 5 host genera of snakes: Clelia, Oxybelis, Pseustes, Rhinobotryum, and Bothriopsis. Infections were also observed in 4 marsupial species and 1 rodent. Hepatozoon spp. recorded in Didelphis albiventris (Marsupialia) and Coendou prehensilis (Rodentia) may be new species. Plasmodium sp. were observed in 2 snake species, Dipsas indica (Colubridae) and Bothrops atrox (Viperidae). Plasmodium brasilianum was recorded in all 5 primate species examined. Piroplasms were observed in all mammal orders except primates. Large terrestrial rodents were the main hosts of members of the Babesidae; 42% of Myoprocta acouchy, 36% of Dasyprocta agouti, and 44% of Agouti paca were infected. Trypanosomes were common in mammals and were recorded in 70% of the examined genera. Trypanosoma cruzi-like infections were reported in 21 mammal species, including sloths, rodents, carnivores, and primates. Microfilariae were also widespread, with higher prevalences in sloths, anteaters, and porcupines (>40% of the individuals infected) and in tamarins (95% infected). This survey highlights some potential anthropozoonotic risks due to the recent further evidence of Plasmodium brasilianum and P. malariae as a single species and to the increased diversity of hosts for Trypanosoma cruzi.     

Subdivided population structure and phylogeography of an endangered freshwater snail, Notopala sublineata (Conrad, 1850) (Gastropoda: Viviparidae), in Western Queensland, Australia

Populations of the Australian freshwater snail Notopala sublineata (Conrad, 1850) have declined rapidly over the last decade, but are still abundant in most river systems of Western Queensland. These rivers are characterized by the unpredictable and highly variable nature of their climatic and hydrological regimes, with episodic periods of very large flow and many periods of little or no flow. We used mitochondrial sequences and allozymes to investigate the genetic structure and infer patterns of dispersal of N. sublineata within this unique environment. We sampled 24 waterholes throughout the four major catchments of the Lake Eyre Basin. Based on a 457-bp fragment of the mitochondrial cytochrome oxidase subunit I gene, we identified 55 haplotypes in a sample of 256 individuals. Both nuclear and mitochondrial genetic datasets indicated high levels of genetic subdivision and restricted gene flow among populations within and among catchments. The mitochondrial haplotypes clustered into two main geographical clades, corresponding with two groups of adjacent catchments: Cooper–Bulloo and Diamantina–Georgina, which appear to have diverged 300 000 years ago. Populations of N. sublineata within these adjacent catchments seem to have diverged relatively recently, roughly 130 000 years ago. Contemporary dispersal seems to be absent between catchments but we suggest that climate fluctuations during the Pleistocene resulted in extensive floods that promoted historical movement of aquatic organisms across catchment boundaries.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 1–16.     

The geography of diversification in the mormoopids (Chiroptera: Mormoopidae)

The traditional explanation of the distribution of the Mormoopidae is that this family originated in southern Central America or northern South America, later expanding its range north to Mexico and the West Indies, and differentiating into eight species. An alternative fossil-based hypothesis argues that the family originated in the northern Neotropics, reached the Caribbean early in its history, and dispersed to South America after the completion of the Isthmus of Panama. The present study analyses new and previously published sequence data from the mitochondrial 12S, tRNA^val, 16S, and cytochrome b , and the nuclear Rag 2, to evaluate species boundaries and infer relationships among extant taxa. Fixed differences in cytochrome b often coincide with published morphological characters and show that the family contains at least 13 species. Two additional, morphologically indistinct, lineages are restricted to Suriname and French Guiana. Phylogeny-based inferences of ancestral area are equivocal on the geographical origin of mormoopids, in part because several internal nodes are not resolved with the available data. Divergences between Middle American and Antillean populations are greater than those between Mexico/Central America and South America. This suggests that mormoopids diversified in northern Neotropics before entering South America. A northern neotropical origin for mormoopids is congruent with both the Tertiary fossil record and recent phylogenetic hypotheses for the sister family to the Mormoopidae, the Phyllostomidae.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 101–118.     

An asymmetrical relationship between an arboreal ponerine ant and a trash-basket epiphyte (Araceae)

The relationship between ants and Philodendron insigne , a trash-basket epiphyte abundant along streams, was studied in French Guiana. Only a few (3%) of the young plants sheltered ants, whereas 90% of the mature individuals did. The most frequent associate was Odontomachus hastatus (Fabricius), an arboreal ponerine ant, and its nests were almost entirely (94.4%) located in P .  insigne root clusters. Experimental choice tests conducted on O .  hastatus workers confirmed their preference for P .  insigne . We propose that the interactions between P .  insigne and ants may be intermediate between non-obligatory, reward-based interactions and obligatory, specific ant–myrmecophyte interactions because (1) almost all mature P. insigne individuals are associated with ants; (2) O. hastatus is the most frequent when diverse ants nest in its root clusters; (3) ants colonize mature P .  insigne , but rarely young individuals; (4) ants, particularly O .  hastatus , protect the foliage of their host; and (5) at least one ant species, O .  hastatus , prefers P .  insigne over other host plants. The latter relationship is asymmetrical because P .  insigne is inhabited by diverse ants whereas O .  hastatus nests almost exclusively in P .  insigne .  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 341–346.     

An autochthonous case of Echinococcus vogeli Rausch & Bernstein, 1972 polycystic echinococcosis in the state of Rondônia, Brazil

The present case report refers to a patient from the State of Rond?nia, North region of Brazil, attended with clinical suspicion of hepatic echinococcosis. Examination by imaging (ultrasonography and computerized tomography) revealed a conglomerate of cystic lesions, with mobile contents within the cyst. The serology (immunoblot) for Echinococcus sp. was positive (21 and 31 kDa bands). This case is the first reported in Rond?nia, suggesting the need to investigate the polycystic echinococcosis in individuals with hepatic cysts from areas of tropical forest and hunting habits where wild life was present as wild dogs, cats and rodents, particularly Agouti paca (paca) and Dasyprocta aguti (agouti).     

Dispersal history of a spider (Stegodyphus lineatus) across contiguous deserts: vicariance and range expansion

Israel marks a crossroads between three continents encompassing several phytogeographical and zoogeographical zones. In this complex area, the flow of species from different biogeographical regions creates opportunities to study how geographical division and colonization routes affect current distribution and structure of resident populations of organisms associated with desert and arid environments, habitats that may have persisted throughout Pleistocene glacial periods. The present paper analyses the population history of the spider Stegodyphus lineatus in the contiguous Negev and Judean deserts in Israel using allozyme and mtDNA variation. The distinct patterns of variation indicate that Judean and Negev populations are vicariant lineages. The residence time was longer in Judea, where populations were more polymorphic for mtDNA, showed isolation by distance and were less structured than in the Negev. The Negev population, possibly linked to other Mediterranean populations of S. lineatus , consisted of two subdivisions derived from a recent eastward expansion across the central Negev watershed. Despite differences in age and level of structure, all lineages show similar dispersal processes dominated by restricted gene flow. The distribution patterns of allozyme and mtDNA markers are unrelated to geographical patterns of precipitation and vegetation. Rather, they follow large-scale topographic features, namely the water divide between Mediterranean and Afro-Syrian rift drainages and between eastern and western Negev drainages.   © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 739–754.     

Phylogeny and historical demography of economically important rodents of the genus Arvicanthis (Mammalia: Muridae) from the Nile Valley: of mice and men

The present study clarified the taxonomy, phylogeny and historical demography of semicommensal Nile rats ( Arvicanthis ) from the Nile Valley in Sudan. Nile rats are important crop pests and zoonotic disease reservoirs and are closely associated with agricultural settlements in the Nile Valley. Phylogenetic analysis of the complete cytochrome b gene (1140 bp) of 23 individuals from six localities in Sudan (from two previously recognized species, Arvicanthis niloticus and Arvicanthis testicularis ), supported the existence of only a single species, A. niloticus , from the Nile Valley. Historical demography of the Sudanese Nile Valley population inferred from mismatch coefficients indicated that an exponential population expansion event occurred approximately 144 000–288 000 years ago, corresponding in time with early human expansion and colonization from Africa to the Middle East, Europe, and the world. The inferred high level of gene flow and large size of Sudanese Nile populations of A. niloticus is consistent with historically recent (300 years ago) exponential human population growth and intense agricultural activity inferred from archaeological and historical evidence. Two African Arvicanthis clades were well supported by the broader phylogenetic analysis: (1) A. niloticus , Arvicanthis abyssinicus and Arvicanthis neumanni and (2) Arvicanthis rufinus and Arvicanthis ansorgei from western Africa. Within the first clade, divergence between lineages of A. niloticus s.s. from west and north-east Africa (8.9%) suggests specific recognition, but sampling of geographically intermediate localities is required. Based on hypothesized palaeodrainage and palaeoclimatic patterns, we propose a simple model for speciation of Arvicanthis in Africa.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 641–655.     

Phylogeography of a host-specific insect: genetic structure of Ips typographus in Europe does not reflect past fragmentation of its host

The phylogeography of the bark beetle Ips typographus was assessed using five microsatellite markers. Twenty-eight populations were sampled throughout Europe on the host tree Picea abies . I. typographus showed very low levels of genetic diversity, and the study revealed a lack of genetic structure across Europe. No significant barrier to gene flow was found, even though P. abies has a fragmented distribution. A weak but significant effect of isolation by distance was found. These results suggest a high dispersal capacity of I. typographus , which leads to low genetic differentiation between populations. Its high dispersal capacity is likely to have prevented I. typographus from developing important local adaptations to its host, which would have influenced its genetic structure. The nuclear data was compared to previously published mitochondrial data that showed strong differentiation between Central–Northern European populations and Russian–Baltic populations, and a founder effect in Scandinavia, probably reflecting the postglacial history of I. typographus . Discrepancies between nuclear and mitochondrial markers could be due to the maternal inheritance of mitochondrial DNA, and to sex-biased dispersal in I. typographus . The overall low genetic diversity observed on both markers on a large geographical scale is discussed. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 239–246.     

Current and historic gene flow of the sand goby Pomatoschistus minutus on the European Continental Shelf and in the Mediterranean Sea

Phylogeographical patterns of the sand goby Pomatoschistus minutus (Gobiidae, Teleostei) were studied by means of sequence and single-stranded conformational polymorphism analysis of a 283-bp fragment of the cytochrome b locus of the mtDNA. A total of 228 individuals sampled at 13 sites throughout the species's distributional range revealed a moderate level of diversity and a low but significant level of overall genetic differentiation at all but one site. The goby sample from the Adriatic Sea differed in sequence by approximately 10% from the Atlantic P. minutus and is thought to belong to a cryptic species of the genus Pomatoschistus . Limited genetic differentiation with a weak pattern of isolation-by-distance was recorded throughout the distributional range of the typical P. minutus . Phylogeographical analysis suggested a contiguous range expansion in the Atlantic and Baltic basins during the Eemian and evidence for a glacial refugium in the southern North Sea during the Weichselian. In P. minutus from the western Mediterranean Sea a high number of endemic haplotypes as well as the most common Atlantic haplotype were recorded in appreciable frequencies. This might be explained by secondary contact between different mitochondrial lineages, which evolved in allopatry.   © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 561–576.     

Testing hypotheses of speciation in the Plethodon jordani species complex with allozymes and mitochondrial DNA sequences

Salamander populations of the Plethodon jordani species complex form a challenging system for applying the general lineage concept of species to diagnose population-level lineages. The present study reports and analyses mitochondrial-DNA haplotypes (∼1200 nucleotide bases from the genes encoding ND2, tRNA^Trp, and tRNA^Ala from 438 salamanders) from 100 populations representing six species of the P. jordani complex ( Plethodon amplus , Plethodon cheoah , Plethodon jordani , Plethodon meridianus , Plethodon metcalfi , and Plethodon montanus ) with comparative analyses of previously published allozymic data to reconstruct the evolutionary history of this group and to diagnose species lineages. Analyses of mitochondrial haplotypic data include nested-cladistic analysis of phylogeography, analysis of molecular variance, hierarchical analysis of nucleotide-diversity measures, and likelihood-based estimates of recent temporal changes in population size. New analyses of allozymic data include multidimensional scaling and principal component analyses, and both data sets are analysed and compared for congruent genetic structure using Mantel correlation tests. These analyses in combination identify the six named species as distinct evolutionary lineages despite sporadic genetic exchanges among them and some discordance between mitochondrial DNA and allozymic markers. Sexual isolation is not complete for any pair of these six species, but they replace each other geographically and appear to block the geographical spreading of their neighbours. The P. jordani complex is a strong study system for investigating the genetic and ecological processes responsible for vicariant speciation.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 25–51.     

Intraspecific vicariant history and the evolution of adaptive morphological diversity in a fish species (Osmerus mordax)

Vicariant geographic isolation and resource partitioning have long been independently identified as processes contributing to the morphological divergence of closely-related species. However, little is known about the extent to which vicariant history influences the adaptive ecological divergence associated with resource partitioning and trophic specialization within species. The present study thus quantified the contribution of vicariant historical genetic divergence to the adaptive contemporary morphological divergence of intraspecific feeding specialists in the Rainbow smelt (Pisces: Osmerus mordax ). This species is characterized by the polyphyletic origin of two lacustrine feeding specialists originating in two intraspecific lineages associated with independent glacial refuges. The historical genetic segregation was initiated approximately 350 000 years ago, whereas the lacustrine trophic segregation arose within the past 10 000 years. Wild caught lacustrine smelt populations were grouped a priori based on known historical genetic identities (Acadian and Atlantic mitochondrial DNA clades) and contemporary feeding specializations (microphageous and macrophageous morphotypes). The present study demonstrated that independent suites of correlated morphological traits are associated with either vicariant history or contemporary feeding specializations. Second, functionally-similar feeding specialists exhibit distinct morphologies resulting largely from vicariant historical processes. Although, the evolutionary processes producing historical phenotypes remains unknown, the results obtained demonstrate how adaptive radiation associated with ecological resource partitioning and feeding specializations can be strongly influenced by intraspecific phenotypic diversification resulting from relatively recent vicariant histories.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 140–151.     

Lineage specific evolution of an alternative social strategy in Tetramorium ants (Hymenoptera: Formicidae)

The western Palearctic ant, Tetramorium moravicum , is the only species of the large genus known to display two alternative social strategies: macrogyny-monoygyny (characterized by one large queen per colony) and microgyny-polygyny (multiple small queens per colony). The microgyne colonies of this ant are confined to the westernmost part of its distribution area and occasionally co-occur with macrogyne colonies. We investigated phylogenetic and geographical patterns in relation to social strategy by analysing 1031 bp of the mitochondrial cytochrome c oxidase subunit I gene of T. moravicum from the entire known species range. Phylogenetic analyses revealed two clear-cut lineages coinciding with the eastern and western populations, which probably were separated after the late Quaternary glacial periods. Geographical distance analysis suggested allopatric fragmentation of the two lineages. We hypothesize that the two lineages colonized Central Europe postglacially from two directions. The current distribution gap of 500 km between the tip of the eastern lineage, in the Czech Republic, Austria and Hungary, and the western lineage, in Germany, was confirmed by hierarchical population analysis. Macrogyny-monogyny probably was the original condition in T. moravicum ; the alternative strategy of microgyny-polygyny may have evolved at the tip of the western lineage, as recently as the early Holocene.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 247–255.     

High photobiont diversity associated with the euryoecious lichen-forming ascomycete Lecanora rupicola (Lecanoraceae, Ascomycota)

The diversity and phylogenetic position of photobionts in the widespread saxicolous, crustose lichen-forming ascomycete Lecanora rupicola s.l. is presented. The algal partners of this lichen species complex belong to diverse and unrelated lineages in the genus Trebouxia . Specimens were sampled from different habitats and geographical origins. Either whole thallus DNA extractions or minute fragments of the algal layer of the lichen thallus were subjected to polymerase chain reaction, using primers that specifically amplify internal transcribed spacer rDNA of the photobionts. No correlations between different chemical races of L. rupicola with particular lineages of Trebouxia spp. were found. Irrespective of the different algal partners, all lichen thalli abundantly developed ascomata. L. rupicola apparently maintains full fecundity with a low degree of selectivity for photobionts, which promotes the occurrence of this lichen-forming species in ample ecological situations.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 283–293.     

Plant polyploidy and the evolutionary ecology of plant/animal interactions

Until recently almost nothing was known about the effects of plant polyploidy on interactions with herbivores and pollinators. Studies of the saxifrage Heuchera grossulariifolia throughout its geographical range in the US northern Rockies have shown that autopolyploidy has probably arisen multiple times within this species since the end of the Pleistocene. Tetraploids from those different origins experience higher levels of attack by the moth Greya politella (Prodoxidae) than sympatric or parapatric diploids. In addition, within one intensively studied region, the plants are also attacked by two other lepidopteran species: G. piperella , which preferentially attack diploids, and Eupithecia misturata (Geometridae), which preferentially attacks tetraploids. Sympatric diploid and tetraploid plants also differ in the overall suites of pollinators they attract. Hence, the evolution of polyploid populations has the potential to change significantly the evolutionary ecology of interactions with herbivores and pollinators. Because a large number of plant lineages include polyploid species, the evolution of plant polyploidy may have had major effects on the interaction structure of terrestrial communities.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 511–519.     

The impact of redefined species limits in Palame (Coleoptera: Cerambycidae: Lamiinae: Acanthocinini) on assessments of host, seasonal, and stratum specificity

Assumptions about the host and stratum specificity of tropical insects are routinely incorporated into estimates of global species richness, but few empirical studies reliably assess tropical insect specificity. In French Guiana, cerambycid beetles in the genus Palame reproduce exclusively in trees belonging to the Brazil nut family (Lecythidaceae). During a year-long rearing project, Palame anceps (Bates) emerged exclusively from a single host species, but P. crassimana Bates and P. mimetica Monné appeared to make seasonal changes in host affiliation. In the case of P. crassimana , dry season specimens could be distinguished from rainy season specimens by subtle differences in pubescence, but it was difficult to find diagnostic morphological characters supporting their delimitation as separate species. In order to detect genetic differentiation in Palame , 1049 bp of mitochondrial DNA (COI gene) were sequenced. The three nominal species of Palame yielded six haplotype groups, with sequence divergences among groups ranging from 8.27 to 17.56%. Species with apparent seasonal changes in host use included multiple distinct haplotype groups that I interpret to represent multiple species-level taxa. Insects considered generalized owing to temporal or geographical changes in host association may, with improved resolution in species limits, prove to be assemblages including relatively specialized cryptic species. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 195–209.     

A giant rhinocerotoid (Mammalia, Perissodactyla) from the Late Oligocene of north-central Anatolia (Turkey)

A giant rhinocerotoid is described for the first time south of the Black Sea, in Turkey. The single specimen, a fragmentary radius referred to Paraceratherium sp., originates from conglomerates nearby at Gözükizilli, in the Çankiri–Çorum Tertiary basin. These layers correspond to the Lower member of the Kizilirmak Formation. The same locality (Gözükizilli-2) yields also the small rhinocerotid Protaceratherium sp., cf. P. albigense (Roman, 1912). Three other mammal localities (Gözükizilli-1, in the Lower Member of the formation, with several rodent species; Tepe 641 and Kizilirmak, in the Upper Member, with a diversified micro- and macro-mammal fauna) allow us to refer the Kizilirmak Formation as a whole to the Late Oligocene. All the observed taxa have strong Asian and/or European affinities, which precludes any geographical insulation for this part of Anatolia during the Late Oligocene.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 581–592.     

Morphological and geographic variation of the cycad Dioon edule Lindl. (Zamiaceae): ecological and evolutionary implications

The relationship in geographical distribution and morphological variation of leaflet width and length (diagnostic trait), between and within populations of Dioon edule Lindl., has been investigated throughout its known range in eastern Mexico (from the states of Nuevo León to Veracruz, north to south, respectively). A total of 1832 leaflets were measured for width and length from 154 plants distributed amongst five populations using four leaflet replicas from each of three leaves per plant. For leaflet width and length the variation among populations indicated significant stat-istical differences ( F _4,147 = 125.83; P  < 0.0001; R ² = 92.17% and F _4,147 = 9.04; P  < 0.001; R ² = 26.8%), respectively. With respect to leaflet width, the multiple range test showed three groups with a north to south distributional relationship along the range of the species. The correlation coefficient among paired populations, respect to geographical distance and the absolute value of the mean difference of leaflet width in each population, was positive, and different from zero ( r  = 0.82; P  = 0.013). A great variation of important ecological and evolutionary parameters was shown.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 465–470.