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1.
《Journal of Natural History》2012,46(8):1245-1258
Patterns of genetic and morphometric variation amongst five populations of Potamonautes parvispina from two rivers in the Western Cape, were examined. Genetic variation at 14 loci was investigated using protein gel electrophoresis. The results showed that the populations were genetically invariant within and between the two drainage systems. Discriminant functions analyses of seven carapace variables demonstrated regional differentiation between the population groups in the two drainage systems. Other morphometric characters exhibited a significant degree of variation within drainage systems. Morphometric data were highly variable and were discordant with the genetic data, which suggests that environmental factors may be responsible for the large degree of phenotypic plasticity. Results from the present study are discussed in terms of widespread gene flow and recent population divergence.  相似文献   

2.
《Journal of Natural History》2012,46(43-44):2693-2703
A vole species, Proedromys liangshanensis Liu, Sun, Zeng and Zhao, 2007 Liu, SY, Sun, ZY, Zeng, ZY and Zhao, EM. 2007. A new vole (Cricetidae: Arvicolinae: proedromys) from the Liangshan Mountains of Sichuan province. China. J Mammal., 88(5): 11701178.  [Google Scholar] (Rodentia: Arvicolinae), which is endemic to the Liangshan Mountains, Sichuan, China, was reported in 2007. The species is restricted to a narrow range because of its weak dispersal ability and habitat specificity, and only lives in fir and spruce forests with abundant grass. In this study, the genetic diversity and phylogeographical structure of 42 P. liangshanensis were examined based on analysis of a partial mitochondrial DNA control region. The results revealed low genetic diversity in the P. liangshanensis populations. Twelve nucleotide haplotypes were defined in the 42 collected individuals, and were divided into two major phylogenetic clades, which were obviously related to geographic pattern. Estimates of gene flow (Nm?=?0.09) also revealed a genetic divergence between the Jinyang and Meigu populations. Species-specific traits, habitat specificity and geographic events contributed to the genetic divergence of the new vole. ?These authors contributed equally to this work.   相似文献   

3.
Seventeen loci were examined for polymorphism in four populations of Neotoma cinerea and Peromyscus maniculatus on isolated mountain ranges in the Great Basin, one population of each in the Sierra Nevada, and one of each in the Rocky Mountains. All Peromyscus populations had higher levels of heterozygosity than syntopic Neotoma populations.  相似文献   

4.
Stenolemus bituberus is an araneophagic “assassin bug” (Heteroptera; Reduviidae; Emesinae) that typically is found living in spider webs. We documented the life history of S. bituberus in the field for 13 months, determining its developmental phenology and microhabitat characteristics as well as describing its mating and predatory behaviour. We also included a morphometric analysis of the instars. Our study revealed that S. bituberus is univoltine with five juvenile instars. Although S. bituberus is found in the webs of spiders from a wide range of genera, it is found most commonly in the webs of Achaearanea, Badumna, Pholcus, and Stiphidion. Multiple juveniles often were found on a single web, but adults tended to be more solitary. Stenolemus bituberus appears to have two distinct hunting strategies: “stalking”, in which they slowly approach the spider, make contact and then strike; and “luring”, in which they attract the spider within range by manipulating the silk with their legs.  相似文献   

5.
《Journal of Natural History》2012,46(23-24):1437-1471
Abstract

Plagiodontes weyrauchi sp. nov. is among the smallest species in the genus Plagiodontes (Doering, 1877). Statistical multivariate analyses confirmed its distinctiveness from other species, mostly because of its high number of whorls (8–9.75), relatively small width, and low proportions of last whorl and aperture length to shell length; multivariate discriminant analysis applied to this species and its most similar relative, P. multiplicatus parvus, correctly identified 100%?of specimens. Pallial and genital anatomy supports P. weyrauchi as a different species, mainly because of the position of the ureteric pore, the small general size of the genital system, the presence of an accessory lobe alongside the verge, and the vaginal internal structure. Internal anatomy of four other small-sized taxa in the genus was studied. Two of them have a verge with no accessory lobe [P. dentatus (Wood, 1828) and P. patagonicus (d'Orbigny, 1835)], while the remaining two have an accessory lobe with different characteristics [P. rocae Doering, 1881 and P. multiplicatus parvus (Hylton-Scott, 1952 Hylton-Scott, M I. 1952. Nuevos moluscos terrestres del norte argentino. Acta Zool Lilloana., 10: 529.  [Google Scholar])]. Internal structure of the vagina also shows specific differences among Plagiodontes species; their phylogenetic significance will be further investigated.  相似文献   

6.
《Journal of Natural History》2012,46(23-24):1591-1638
Following an up‐to‐date synopsis on the planthopper fauna and their associated host‐plants in the Mascarene Islands including numerous new data, a study of host plant and Fulgoromorpha interaction patterns illustrates some remarkable specificities. The endemic fauna remains essentially on endemic plants and exotic planthoppers have not shifted to them, remaining on exotic plants. Two fulgoromorph families are strictly associated with monocotyledons: (1) the Delphacidae represented by widespread species maintain the same host as the continental source populations, especially exotic Poaceae and (2) the Derbidae which displayed a food conservatism for woody plants are found mostly on endemic Arecaceae, Pandanaceae and Liliaceae. These relationships differ from continental Derbidae, which are recorded as much on dicotyledons as on monocotyledons. Other island specificity appears with the endemic species of Meenoplidae from La Réunion, which are recorded on endemic dicotyledons whereas the continental species are recorded on monocotyledons. In La Réunion, a positive correlation between endemic planthopper diversity recorded on different host plants and endemic plant diversity within different plant orders was observed. This result suggests a stochastic distribution of the planthoppers on the available botanical taxa at the time of colonization. In the Mascarenes, disparities appear between Cixiidae from La Réunion and Mauritius. On the latter, the Cixiidae seem to be mainly monophagous and the majority of them are recorded on Rubiaceae.  相似文献   

7.
《Journal of Natural History》2012,46(6):1495-1505
Ectoparasitic tantulocaridan crustaceans, Microdajus aporosus sp. nov., were found attached to the tanaidacean crustacean Meromonakantha macrocephala (Hansen) from 568 m in the Ross Sea. A single host bore on its pereiopods five expanded tantulus larvae with gestating males and two isolated cephalons of the parasite. Microdajus langi Greve is newly reported from the Gullmarfjord, Sweden. A recent comparison of tantulocaridan thoracopods to maxillopodan naupliar appendages is evaluated in the light of recent morphological and ontogenetic findings.  相似文献   

8.
《Journal of Natural History》2012,46(33-34):2007-2026
Based on an examination of material from different areas of the American continent, we evaluate the morphological variations of Eucyclops elegans (Herrick, 1884) with an emphasis on characters used in the current taxonomy of the genus. Eucyclops elegans is clearly a member of the serrulatus group. Differences in both female and male specimens from North America and South America and the lack of records in southern Mexico and Central America suggest that it is possible that this nominal species contains at least two taxa. Characters such as the ornamentation of the antennal basis and coxa of P4 are described for the tropical species E. conrowae Reid, 1992. This species is clearly not a member of the serrulatus group and differences with respect to the type specimens indicate that records of E. conrowae in Mexico do not correspond to this taxon and should be reassigned to other species.  相似文献   

9.
《Journal of Natural History》2012,46(17-20):1227-1235
In this study we analysed the acoustic activity of Hylodes heyeri in areas of Atlantic Forest, in southern Brazil. Observations were made in November 2001 and from January to April 2002, at Estação II Instituto Agronômico do Paraná, municipality of Morretes, State of Paraná. Males displayed three different vocalizations: advertisement calls, territorial calls, and courtship calls. Temporal and spectral parameters of advertisement and territorial calls were analysed, along with call intensity. The duration of the advertisement call showed a negative correlation with air temperature, with males decreasing the duration of advertisement calls at higher temperatures. Male body size was not correlated with any of the acoustic parameters. Details on habitat use, distances to nearest vocalizing neighbour, and daily calling activity are also included.  相似文献   

10.
《Journal of Natural History》2012,46(41-42):2577-2604
The influence of temporal variation in the host specificity of invertebrates to estimates of biodiversity is rarely considered. While patterns at large spatial scales have stimulated much attention, such comparisons are constrained for southern-hemisphere biomes because the patterning of invertebrates on plants is largely unknown. Here, we analyse variation of plant-dwelling Hemiptera from 15 understorey plant species over 18 months in the south-west Australian biodiversity hotspot. Analyses showed significant interactions in species composition between sampling period and plant species. Fauna that were “effectively specialized” (host-specificity index) to plants changed with season, although this was also related to the number of singletons and overall species richness. Sampling from a single season also overestimated the degree of host specificity by 52% and underestimated the perception of species richness when an outbreak of a particular herbivore occurred. High host-specificity values (12.7 hemipteran species per plant) support the case for high estimates of global arthropod richness.  相似文献   

11.
12.
《Journal of Natural History》2012,46(21-22):1387-1405
Earthworms are excellent indicators of landscape fragmentation due to their widespread distribution and poor dispersal abilities over water. Based on field studies conducted in the Shandong and Liaodong peninsulas and their associated islands during summer 2009, we analysed the genetic variation of Drawida japonica Michaelsen, 1892 (Oligochaeta, Moniligastridae) using DNA sequences of the 16S and 28S ribosomal genes in samples obtained from 13 localities, 12 of which were islands, one artificially connected to the mainland by man (Yangma SC). We identified 55 haplotypes among 79 samples, based on 1094 bp, including 47 unique haplotypes. The phylogenetic tree topologies showed two distinct clades. A multiple-apex Poisson distribution using a mismatch analysis of nucleotides was also detected. Results of a Tajima D neutral test were not significant (p > 0.05). Genetic divergence among populations was much larger than within populations. A positive relationship between genetic diversity and island area was revealed, but no significant correlation between genetic diversity and distance to the nearest larger landmass was found. These results indicate that the intraspecific genetic diversity of D. japonica has been influenced by geographic isolation (i.e. island habitat). Passive transport via anthropogenic activities or nonhuman vertebrates (birds or mammals) may also play a key role in dispersal.  相似文献   

13.
The Leptodactylus pentadactylus species group is comprised of medium to large species of Neotropical frogs. Leptodactylus knudseni, a member of this species group, has a wide distribution throughout the Amazon Basin. Herein we describe aspects of the reproductive biology of L. knudseni and provide notes about the ontogenetic variation of its tadpoles based on a population in a non-flooded forest near Manaus, Amazonian Brazil. Amplectant pairs of L. knudseni lay foam nests in excavated basins on the edge of temporary ponds located on clay soil and at least 50 m from a stream. The tadpole development happens initially in the foam nests with access to the pond after the rain flooding the basins. Studied clutches lacked trophic eggs and tadpoles did not produce foam. Ontogenetic variations in L. knudseni tadpoles are related to size, teeth formulae and body colour. The use of excavated basins for the deposition of foam nests has been reported in several species of the L. pentadactylus group. The absence of trophic eggs and production of foam by the tadpoles differ from other species of the L. pentadactylus group. The tadpole morphology is similar to that described for other species of the group.  相似文献   

14.
《Journal of Natural History》2012,46(42):3633-3647
The muscular anatomy and fine structure of the haptor of a monogenean, Capsala sp., together with an observational distribution study, are described from specimens collected from the dorsolateral and ventral surfaces of the blue marlin, Makaira nigricans. The haptor is composed of seven loculi, which are arranged around a central pair of accessory sclerites. Marginal hooklets and hamuli were not observed. The presence of an outline left by the haptor on the host's skin and the lack of evidence of an adhesive secretion suggested that the haptor attaches primarily by suction. Tendons originating in the extrinsic peduncle muscles insert, via a proximal notch in the accessory sclerites, into the basal tegumental lamina on the ventral surface of the haptor. On contraction the centre of the haptor is thought to be drawn upwards both directly by the extrinsic tendons in the haptoral wall but also by the accessory sclerites which are brought into a vertical position. This increases the volume beneath the haptor, consequently reducing the pressure and thus producing suction. The ribbed marginal valve prevents the inward movement of water. Intrinsic circular and radial muscles in the haptoral wall are also thought to produce suction by drawing the haptoral wall inwards, again increasing the volume beneath and causing a pressure reduction. It is suggested that interconnecting fibres observed between the intrinsic muscles may store elastic energy, allowing Capsala sp. to maintain suction attachment without having constantly to contract its muscles. Papillae on the inner ( = ventral) surface of the haptor are suggested to aid attachment by firstly spreading the negative pressure over the inner surface of the haptor and, secondly, through resisting the shear forces encountered as the fish swims. Both functions are achieved by increasing the surface area of contact with the host's skin, and therefore the frictional forces. Theoretical estimates of the suction efficiency indicate that suction is double the maximum theoretical drag forces which would be experienced by Capsala sp. when M. nigricans is swimming at speeds of both 1 and 20 m s?1 and suggests that suctorial attachment is efficient. The distribution of Capsala sp. is not thought to be restricted by the surface topography of the host, demonstrated by the fact that individuals were located in both the roughest and smoothest areas of the marlin's skin surface. Distribution is therefore thought to be influenced by other factors such as hydrodynamics, nutritional value of the attachment site, immunological restrictions or cross‐fertilization between parasites.  相似文献   

15.
A brief account of the present state of weevil taxonomy is followed by a detailed study of certain structures used in their classification, namely the venter, abdominal tergites, sternite 8 of the male, apex of the hind tibia and deciduous mandibular processes. A key to some 50 families and subfamilies of Curculionoidea is followed by a list of family-group taxa. The following changes are made: Brachyceridae, Erirhinidae, Cryptolaryngidae and Raymondionymidae are promoted to family rank from Curculionidae; Antliarhininae is demoted to a subfamily of Brentidae, and Allocoryninae to a subfamily of Oxycorynidae; Coptonotini is demoted to a tribe of Curculionidae-Scolytinae; Carinae, Subfam. n. is erected for Car Blackburn (genus incertae sedis) is Belidae; Dinomorphini is demoted to a tribe of Molytinae and Brachyceropsidinae is revived from synonymy with Dinomorphinae (Curculionidae); Brachyderini, Eremnini, Otiorhynchini and Sitonini are demoted to tribes of Entiminae; Desmidophorinae is transferred from Brentidae to Brachyceridae; Ocladiini is promoted to a tribe of Desmidophorinae (from Curculionidae-Cryptorhynchinae); Campyloscelini (including Phaenomerina) is transferred from Rhynchophoridae to Curculionidae-Zygopinae; Carphodicticinae is promoted to subfamily rank and transferred from Curculionidae-Scolytinae to Platypodidae; Perieges Schönherr is transferred from Curculionidae-Thecesterninae to Cryptolaryngidae and Agriochaeta Pascoe from Cryptorhynchinae to Hyperinae (Curculionidae); Schedlarius Wood and Mecopelmus Blackman are transferred from Coptonotidae to Platypodidae.  相似文献   

16.
The anatomy of a new species of heteronemertean from the Mediterranean, Oxypolella banyulensis sp. nov., is described and illustrated. The species is characterized by having a dermis comprising subepidermal longitudinal muscle fibres arranged in characteristic piles, a three-layered proboscis with four main regions, one ciliated pit in the frontal organ, two dorsal nerves and a thin inner circular muscle layer. Further notes on Oxypolella bergendali are given.  相似文献   

17.
A new species of mealybug from southern Asia, Dysmicoccus finitimus sp. nov., is described. It has often been confused with D. cocotis (Maskell), to which it is closely related. Both species are common on coconut and often occur in sufficient numbers to cause growers concern. D. cocotis is known from a wide area of Micronesia, Polynesia and Melanesia, but it is not known to occur west of the Federated States of Micronesia in the north and Fiji in the south. There are no records of D. cocotis from the Solomon Islands or Papua New Guinea, despite extensive collecting on coconut in these territories. D. finitimus is confined to southern India, Sri Lanka, Cocos (Keeling) Islands and peninsular Malaysia. There are no records yet of the new species from Indonesia.  相似文献   

18.
《Journal of Natural History》2012,46(17-18):1089-1099
The blissine bug Macropes obnubilus, which lives aggregately under leaf sheaths of the evergreen dwarf bamboo, is infected by the strepsipteran parasite Blissoxenos esakii. To determine the ecological properties of the bug–strepsipteran system, we conducted field surveys of natural populations of Macropes bugs and Blissoxenos parasites. The parasitism rate of strepsipterans was high throughout the year and was significantly higher in female than in male bugs. Blissoxenos adult males emerged mainly in May, and neotenic adult females released triungulins in August. The triungulins invaded host nymphs, but subsequent larval development did not occur before the bugs matured. At most, two strepsipterans could mature in a host because of spatial limitations. The mortality of triply or more parasitized bugs was significantly higher than that of singly or doubly parasitized bugs, which survived longer than uninfected ones. The heavy strepsipteran infection profoundly affected the host population by causing host reproductive failure.  相似文献   

19.
20.
《Journal of Natural History》2012,46(17):2145-2152
During a recent biological investigation of submarine caves of Grand Cayman, the Caribbean Sea, two species of Heteromysoides were collected. One species, referred to Heteromysoides spongicola B?cescu, 1968 Baˇcescu, M, 1968. Heteromysini nouveaux des eaux cubaines: trois espèces nouvelles de Heteromysis et Heteromysoides spongicola n. g. n. sp., Revue Roumaine de Biologie, Zoologie 13 (1968), pp. 221237. [Google Scholar], is known only by the type specimens; therefore, this discovery marks the second record of occurrence and a new habitat record for the species. The other species is considered new and is described as H. stenoura, a 10th species of the genus. The new species closely resembles H. simplex Hanamura and Kase, 2001 Hanamura, Y, and Kase, T, 2001. A new species of Heteromysoides (Mysidacea: Mysidae) from submarine caves of Okinawa, southwestern Japan, with a key to the world species, Crustacean Research 30 (2001), pp. 6571.[Crossref] [Google Scholar], known from the submarine caves of Okinawa, north-western Pacific, in the possession of a spiniform process on the eyes and a simple termination to the third thoracic endopod. However, the new species can be readily distinguished from the Pacific congener by a distally narrow telson and a more developed cornea in the eyes.  相似文献   

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