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1.
Micropleura huchzermeyeri n. sp. (Camallanida: Dracunculoidea: Micropleuridae) is described from the peritoneal cavity of Crocodylus niloticus Laurenti (Reptilia: Crocodylidae), based on a detailed study of its morphology using light and scanning electron microscopy. The new species is compared with its congeners, M. australiensis Moravec, Kay & Hobbs, 2004, M. vazi Travassos, 1933 and M. vivipara von Linstow, 1906 from crocodilians, and with M. indica Khera, 1951 from chelonian hosts. It can be distinguished from these by the length of its spicules, which are longer than in all described species and a combination of characters, including the presence of prominent lateral caudal papillae on the level of the cloaca in males, the presence of conspicuous phasmids on the female tail, the pre-equatorial position of the vulva and the length of the first-stage larvae. Micropleura huchzermeyeri n. sp. is further characterised by having 14 cephalic papillae in both sexes and ten pairs of caudal papillae in males. This is the first report of a representative of the genus Micropleura von Linstow, 1906 from a crocodilian in the Afrotropical region. Micropleura helicospicula Dey Sarkar, 2003 is considered a species incertae sedis.  相似文献   

2.
Leptodactylus paraensis Heyer, is a Neotropical anuran species that inhabits Rainforest habitats in the eastern Amazon, but because it has only been recently separated from the Leptodactylus pentadactylus (Laurenti) species group, little is known about its helminth fauna. This study describes a new species of Oswaldocruzia Travassos, 1917 and records the first occurrence of this genus parasitising L. paraensis and the second species for the Caxiuanã National Forest in the eastern Amazon, Brazil. Oswaldocruzia lanfrediae n. sp. is characterised by having an anterior extremity with a smooth cephalic vesicle divided into two portions, a claviform oesophagus, well-developed cuticular longitudinal ridges and lateral alae. Females have a well-developed ovojector, with didelphic and amphidelphic uteri. Males show complex robust spicules divided into a slightly curved shoe, a bifurcated fork and a blade terminating in 2–3 processes. The new species differs from its congeners especially regarding the lateral alae and the morphology of the spicules, in addition to morphometric characters such as body size, oesophagus length, deirid position, nerve-ring position and relative position of the vulva in females.  相似文献   

3.
Neoascarophis sinensis n. sp. collected from the whitespotted conger Conger myriaster (Brevoort) (Anguilliformes: Congridae) in the Yellow and East China Seas, is described using both light and scanning electron microscopy. The new species is characterised mainly by the body size (8.5–10.5 mm in the males, 9.5–14.0 mm in the females), the location of the vulva (near equatorial region of the body), the non-bifurcate deirids, the lengths of the vestibule (40–50 µm in the males, 30–60 µm in the females) and glandular oesophagus (2.5–3.1 mm in the males, 3.1–3.5 mm in the females) and the morphology and length of the spicules (left spicule 400–410 µm, right spicule 130–150 µm). Neoascarophis sinensis n. sp. is the first species of Neoascarophis Machida, 1976 reported from the anguilliform fish and is also the only species of this genus found in the Chinese waters.  相似文献   

4.
Many species of the butterfly genus Phengaris are regarded as endangered in many parts of their distribution. Several species are also widely distributed across northern China. Due to land use change and overgrazing, their habitats are declining and many patches have been lost. This paper investigates the distribution and habitats of the Chinese Phengaris species (of the subgenus Maculinea). Shrub-grassland near forests seem the most frequent habitat for Phengaris, while flat open grasslands are mostly over-grazed and thus survival for Phengaris butterflies there seems difficult. Throughout Europe, P. teleius is an endangered species, while there is still no information on its status in China. To improve the knowledge on the population ecology of P. teleius, its population structure, adult behaviour and movement were studied through mark–release–recapture methods in the Qinling Mountains of Taibai County. Eight grassland patches which were potentially suitable were found in the area in 2013. In total, 480 individuals (274 females) were marked, resulting in an overall recapture rate of 16 %. The average daily population size was 44 butterflies (±23 SD) during the adult flight period. Sixty-seven percent of the females and 38 % of the males moved less than 50 m, and 17 % of recaptured females and 38 % of males moved more than 200 m. The mean movement distance was 107 ± 177 m for males and 182 ± 122 m for females. The majority of the recaptures (86 %) were made within the patches, only a few individuals (14 %) moved between patches. Due to human disturbance and destruction, all of the eight potentially suitable patches are becoming smaller and increasingly isolated, thus these populations of P. teleius may face an increasing risk of extinction, which may well be a tip of the iceberg of habitat loss and fragmentation of P. teleius in Taibai County and possibly beyond. Hence we hope our initial study of P. teleius could have positive impacts on the conservation of Phengaris butterflies in China.  相似文献   

5.
A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy.  相似文献   

6.
Feeding of predatory mites (Phytoseiulus persimilis, Galendromus occidentalis, and Neoseiulus cucumeris) on different life stages of Tetranychus atlanticus under optimal conditions was studied. Daily and total consumption of prey by predators and selection of prey of different life stages were studied for 5 days and for the entire feeding period. Average daily food consumption [number of individuals] for the entire life period of mature mite females constituted 0.43 females + 5.0 [nymphs and males] + 3.4 eggs of Tetranychus atlanticus in P. persimilis; 0.12 females + 3.70 [nymphs and males] + 3.10 eggs in G. occidentalis; and 0.19 females + 4.10 [nymphs and males] + 3.50 eggs in N. cucumeris. During the entire period of feeding, P. persimilis preferred large individuals and at the postembryonic stages selected prey to a greater extent than G. occidentalis and N. cucumeris (61.8 and 55.1%, respectively). The use of a 5-day express-method is possible for estimation of some biological characteristics of phytoseiids that previously consumed the same food for a long period. In other cases, analysis of characteristics for the entire life period is necessary.  相似文献   

7.
The demography and reproductive biology of three Epinephelus groupers (Serranidae), namely E. polyphekadion, E. tauvina, and E. howlandi in the Yaeyama Islands, Okinawa, were examined based on age assessment using otoliths and gonadal histology. The maximum ages for these three species were 26 year, 23 year, and 17 year. The von Bertalanffy growth functions were also determined for each species. The size and age at 50% female maturity were estimated to be 358 mm in total length (TL) and 6.0 year for E. polyphekadion, 371 mm TL and 6.7 year for E. tauvina, and 327 mm TL and 4.1 year for E. howlandi, respectively. Significant differences between the sexes in size and age frequencies were found in all three species, with males being larger and older than females, or transitional individuals. These results strongly indicated that the population of these three grouper species showed monandric protogynous hermaphroditism. The sex ratios of E. polyphekadion and E. tauvina were biased in favor of females, but that of E. howlandi was equivalent between sexes. The relative sizes of ripe testes indicated that the intensity of sperm competition varied among species suggesting different mating system of each species. Reproductive seasonality was similar among species, with active vitellogenesis coinciding with the annual rise in water temperature. The active spawning period was determined to be between April and May for E polyphekadion, in May for E. howlandi, and from March to June for E. tauvina.  相似文献   

8.
This study evaluated rickettsial infection in ticks collected on toads from the northern Brazilian Amazon (Amapá state), where to our knowledge there are neither records of ticks from amphibians nor rickettsial infections in ticks. During 2016–2017, a total of 22 free-living toads were captured and identified as Rhinella marina. Overall, 12 (54.5%) toads were parasitized by a total of 97 ticks (6 males, 39 females, 31 nymphs, 21 larvae), giving a mean intensity of 8.1 ticks per infested toad. Two tick species were morphologically identified: Amblyomma rotundatum Koch (31 females, 14 nymphs), and Amblyomma dissimile Koch (6 males, 8 females, 17 nymphs). The 21 larvae were morphologically denoted as Amblyomma sp. Five toads were co-infested by A. rotundatum and A. dissimile. Morphological identifications were confirmed by nucleotide sequencing of fragments of the mitochondrial genes 16S rDNA, 12S rDNA and/or COX1. A total of 54 ticks were analyzed for the presence of rickettsial DNA. Eleven (9 females and 2 nymphs) out of 14 A. rotundatum ticks contained Rickettsia bellii. None of the 25 specimens of A. dissimile (6 males, 6 females, 13 nymphs) contained amplifiable rickettsial DNA. From 15 Amblyomma sp. larvae, a pool of 10 individuals contained Rickettsia sp. strain Colombianensi. Sequencing of the 16S rDNA amplicon derived from the positive pool yielded a sequence of A. dissimile. We detected Rickettsia sp. strain Colombianensi for the first time in Brazil. Prior records of this agent were restricted to Colombia and Honduras. In addition, we report the presence of A. rotundatum for the first time in the state of Amapá, where the only other record of A. dissimile was registered over 20 years ago.  相似文献   

9.
Neocosmocercella fisherae n. sp. is the first nematode species found parasitising Phyllomedusa bicolor from the Brazilian Amazon Region. The new species has a triangular oral opening, with bi-lobed lips, and is distinguished from N. bakeri (triangular oral opening with simple lips), and from N. paraguayensis (hexagonal oral opening with bi-lobed lips). Additionally, the new species has ciliated cephalic papillae, which are absent in the other species of the genus. The reduced uterine sac and the presence of a single egg in the uterus in females are the main morphological characters that differentiate the new species from its congeners N. bakeri (8–10 eggs) and N. paraguayensis (10 eggs, based on the allotype). Additionally, the new species differs from the other two species of the genus by morphometric characters such as the size of spicules and gubernaculum in males and the vagina in females. Until now, phyllomedusid anurans are the only known hosts for the nematodes of this genus. The present work describes the third species of the genus and the first species of nematode parasitising P. bicolor.  相似文献   

10.
The subgenera Roelofsideporaus and Deporaus s. str. of the genus Deporaus with four species (D. affectatus, D. unicolor, D. nidificus, and D. betulae) recorded from the Russian fauna are revised. Keys to the species of the subgenus Roelofsideporaus and to the females of the subgenera Roelofsideporaus and Deporaus s. str. are given. The distribution of D. nidificus in Russia is not confirmed.  相似文献   

11.
12.
Rapid displacements of resident Aedes aegypti by invasions of Aedes albopictus have been documented in the southeastern United States and Bermuda. Interspecific mating has been detected in nature between these species and proposed as a likely mechanism for these displacements by means of asymmetric reproductive interference, or satyrization. However, rapid displacements of A. aegypti have not been detected in most localities where these two invasive species are known to co-occur. Aedes albopictus invaded the United States and Brazil at approximately the same time, in the mid-1980s, but the origins of the invading strains are known to be different. Here we tested the hypothesis, in standardized cage environments, that A. albopictus males from Brazil are less capable of satyrizing A. aegypti females than A. albopictus males from the United States. Using strains of A. aegypti and A. albopictus from the United States of known susceptibility to and capacity for interspecific mating, we demonstrate that A. albopictus colonized from collections in the Brazilian cities of Rio de Janeiro and Manaus were relatively unsuccessful in inseminating virgin female A. aegypti from Key West Florida compared to A. albopictus from peninsular Florida. We suggest that the low satyrization potential of Brazilian A. albopictus males may contribute to the lack of documented competitive displacements of A. aegypti in that country.  相似文献   

13.
Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.  相似文献   

14.
To determine biologically important effects of the cytoplasmic endosymbiont Wolbachia, two substrains of the same Drosophila melanogaster strain have been studied, one of them infected with Wolbachia and the other treated with tetracycline to eliminate the bacterium. Females of D. melanogaster infected with Wolbachia are more resistant to the fungus Blauveria bassiana (an insect pathogen) than uninfected females; infected females also exhibited changes in oviposition substrate preference. Males infected with the bacterium are more competitive than uninfected males. The possible role of Wolbachia in the formation of alternative ecological strategies of D. melanogaster is discussed.  相似文献   

15.
The effect of strong hypomorphic mutation of the insulin-like protein gene (dilp6) on metabolism of octopamine (one of the main biogenic amines in insects) was studied in Drosophila melanogaster males and females. The activity of tyrosine decarboxylase (the key enzyme of octopamine synthesis) and the activity of octopamine-dependent N-acetyltransferase (the enzyme of its degradation) were measured. It was demonstrated that the activity of both studied enzymes is decreased under normal conditions in the dilp641 mutants (as we previously demonstrated, this is correlated with an increased level of octopamine). It was also found that hypomorphic mutation of the dilp6 gene decreases the intensity of tyrosine decarboxylase response to heat stress. Thus, it was demonstrated for the first time that insulin-like DILP6 protein in drosophila influences the level of octopamine (regulating the activity of the enzyme degrading octopamine).  相似文献   

16.
In this contribution on the genus Cantharellus in Asia, C. subvaginatus is described from the Republic of Korea as a close relative to the Chinese C. vaginatus, which is here reported for the first time from India. Both species are here placed in Cantharellus subg. Cantharellus sect. Amethystini, together with the Indian C. pseudoformosus (syn.: C. umbonatus) and the Malayan C. subamethysteus. As such, Asia has suddenly become the continent with the highest diversity for Amethystini. Species delimitation in sect. Amethystini is molecularly supported by a combined phylogenetic analysis of rDNA sequences obtained for LSU and ITS and additionally suggests the existence of a still undescribed species in North America. Character variability is discussed for all known members of Amethystini, including atypical specimens of the North American C. lewisii that are morphologically more reminiscent of the South Korean C. subvaginatus.  相似文献   

17.
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.  相似文献   

18.
We describe the mating behaviour of males of Centris (Paracentris) burgdorfi, a solitary, univoltine bee, with a wide distribution in Brazil. We also describe the unusual sleeping sites of males and females. The study was performed during two breeding seasons, in northeastern Brazil, where the species nests in aggregations in petrified dunes. Data on mating behaviour were collected through direct observations of the bees at the nesting-emergence site. Males compete intensely for virgin females in the morning, sometimes killing rivals. The high competition for females near the nesting site makes that the male has to take the female to another place to get genital contact. In the evening, males do not use plants to spend the night, instead they aggregate in sleeping clusters inside old burrows in the nesting-emergence area while females sleep in groups on plants that provide the floral oil used in nest construction.  相似文献   

19.
The feeding habits and trophic ecology of Mustelus lunulatus and Mustelus henlei in the central coast of the Colombian Pacific were evaluated and compared to determine whether there was trophic niche overlap or resource partitioning between these two sympatric shark species. A total of 59 prey items were identified and grouped into 10 taxonomic categories. Mustelus lunulatus fed in large proportion on Stomatopoda and Brachyura, whereas M. henlei fed almost exclusively on Teleostei. Dendrobranchiata, Cephalopoda, Anomura and Polychaeta complemented the diets of both species. There were significant differences in diet between the two species, and there was an ontogenetic diet shift in Mustelus lunulatus, with Stomatopoda being the main prey item of juveniles and Brachyura the main prey item of adults. Dietary overlap (by sex and size) was low between species, but it was high for each species, with significant overlap between juveniles and adults of M. lunulatus and M. henlei, and between males and females of M. henlei. There were differences in the trophic levels of the species, sexes and sizes. This study suggests there is food resource partitioning, and differing ecological function of the two Mustelus species in the food web of the study area.  相似文献   

20.
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