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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.
Three new species of the parasitic nematode genus Cloacina von Linstow, 1898 (Strongyloidea: Cloacininae) are described from the stomachs of wallaroos, Osphranter spp. (Marsupialia: Macropodidae), from northern Australia. Cloacina spearei n. sp. is described from O. robustus woodwardi (Thomas) and O. antilopinus (Gould) and is distinguished from congeners by the shape of the cephalic papillae, the shallow buccal capsule, the presence of an oesophageal denticle and the convoluted but non-recurrent vagina in the female. Cloacina longibursata n. sp. also from O. robustus woodwardi and O. antilopinus is distinguished from congeners by the elongate dorsal lobe of the bursa, with the origin of the lateral branchlets posterior to the principal bifurcation, in the features of the spicule tip, the lack of bosses lining the oesophagus and the absence of an oesophageal denticle. Cloacina crassicaudata n. sp., from the same two host species was formerly identified as C. cornuta (Davey & Wood, 1938). Differences in the cephalic cuticle (inflation lacking in the new species), the shape of the cephalic papillae, the dorsal oesophageal tooth and the spicule tips, as well as differences in the sequences of the internal transcribed spacers of the nuclear ribosomal DNA, indicate that this is an independent species. The geographical distribution of this species is disjunct with populations in both the Northern Territory and Queensland. Possible reasons for the disjunct distribution are discussed.  相似文献   

3.
Lestrimelitta spp. are stingless bees that steal food and nesting materials from other highly social bees to survive. Though most of their victim species respond, either aggressively or submissively, to cephalic components of Lestrimelitta, little is known about if such response changes at some point during extended periods of exposure. Moreover, potential synergistic effects due to a mixture of victim’s alarm/defense pheromones and Lestrimelitta mandibular pheromones, like in an actual attack, have not been examined so far. In this paper, we investigated the response of two species of non-robber stingless bees, Scaptotrigona mexicana (Guérin) and Tetragonisca angustula (Latreille), to (a) cephalic compounds from crushed heads of nestmates, (b) cephalic compounds of Lestrimelitta niitkib (Ayala), and (c) a mixture of (a) and (b). We found that even though T. angustula did not react to nestmates’ crushed head, its response towards L. niitkib cephalic compounds was stronger and lasted longer than that of S. mexicana. Interestingly, the addition of crushed heads of the non-robber species to L. niitkib crushed heads caused no significant increase in the alarm response of both species. It may be that the absence of an alarm pheromone in T. angustula made this species more receptive to extraneous odors, which is not the case for S. mexicana; however, more species must be studied to elucidate any pattern regarding the absence/presence of alarm pheromones and the corresponding response to intruders’ pheromones.  相似文献   

4.
5.
Microchelonus species of the M. retusus group differ from the other members of the subgenus Microchelonus s. str. (characterized primarily by the 16-segmented female antennae and deepened apical abdominal opening of the male) in their elongate carapace of female abdomen more strongly narrowed apically than toward base. The first key to 45 species of this group, including 7 new species, is given: M. alexeevi Tobias, 1986 (apicalis Alexeev, 1971); M. angustiventris Tobias, 1986; M. apicalis Papp, 1971; M. arnoldii (Tobias, 1964); M. artus Tobias, 1986; M. cisapicalis Tobias, 1989; M. crassitarsus Tobias, 1989; M. dolosus Tobias, 1989; M. elenae Tobias, 1995; M. erosus Herrich-Schaeffer, 1838 (analipennis Fahringer, 1934; hungaricus Szépligeti, 1896; frivalaldszkyi Shenefelt, 1973); M. heraticus Tobias, 1985; M. hofferi Tobias et Lozan, 2006; M. jonaitisi Tobias, 2000; M. justus Tobias, 1989; M. kievorum sp. n. (Ukraine); M. kiritshenkoi (Tobias, 1976); M. klugei Tobias, 2001; M. kopetdagicus (Tobias, 1966) (caucasicus Abdinbekova, 1967, syn. n.); M. korinthiacus sp. n. (Greece); M. kozlovi (Tobias, 1961); M. longirimosus Tobias, 1995; M. madridi sp. n. (Spain); M. marshakovi Tobias, 1986; M. mediterraneus sp. n. (Greece); M. microphthalmus (Wesmael, 1838) (dilatus Papp, 1971); M. mikhaili Tobias, 1989; M. mirabilis (Tobias, 1972); M. morrocanus sp. n. (Morocco); M. nachitshevanicus (Abdinbekova, 1971); M. ononicus Tobias, 2000; M. pamiricus (Voinovskaya-Kriger, 1928); M. retrusus Tobias, 1989; M. retusus (Nees, 1813) (caudatus Thomson, 1874); M. stenogaster Tobias, 1995; M. sternaus (Tobias, 1964); M. subcaudatus (Tobias, 1971); M. subjustus sp. n. (Spain); M. sulcatus Jurine, 1908 (rimulosus Thomson, 1874; rimatus Szépligeti, 1896); M. tersakkanicus Tobias, 2001; M. tjanshanicus Tobias, 1995; M. turcius sp. n. (Turkey); M. volgensis Tobias, 1986; M. xenia Tobias, 2000; M. zorkuli Tobias, 1991.  相似文献   

6.
A nearly complete skeleton, including most of the thoracic member bones of the sloth Mylodon darwinii, have been found in Upper Pleistocene strata from Anisacate River, Argentina. The thoracic member bones resemble their homologues in Glossotherium robustum, Paramylodon harlani, and Mylodonopsis ibseni in the following traits: (1) the olecranon is mediolaterally compressed; (2) the radius has an acute styloid process; (3) the radial diaphysis medial border is straight for two thirds of its length; (4) the radial shaft medial border forms an angle with the medial border of the styloid process. The radius presents a distinctive, mostly proximally facing articular circumference. The unfused epiphyses and feeble muscle attachment ridges indicate a sub-adult ontogenetic stage. Deviation of the olecranon and weak M. teres major origin and insertion, suggest a low fossorial specialization. The structure of the thoracic limb bones does not support climbing habits, because pronation-related features are reduced and the humeral head is not prominent. The structure of the radius suggests graviportal adaptations: the proximal head is mediolaterally expanded and the diaphysis straight. A phylogenetic analysis adding thoracic member characters recovers M. darwinii as part of a clade that includes Glossotherium robustum and Paramylodon harlani, but excludes Lestodon armatus. This contrasts with the results of previous analyses focusing on the head skeleton, highlighting the relevance of sampling postcranial characters in phylogenetic analyses of mylodontine sloths.  相似文献   

7.
The study investigated interspecific agonistic behavior of Macrotermes gilvus Hagen (Isoptera: Termitidae: Macrotermitinae) against three economically important subterranean termites in the Philippines, viz., Coptotermes gestroi Wasmann, Nasutitermes luzonicus Oshima and Microcerotermes losbanosensis Oshima. Termite-termite interactions after a 1:1 pairing experiment showed that M. gilvus workers and soldiers were highly aggressive against C. gestroi, N. luzonicus and M. losbanosensis leading to severe injury or death of the opponent termite species in a short period of time. The levels of agonism were caste and species specific. Worker termites of M. gilvus showed an equally aggressive behavior as soldiers contributing to the high mortality of opponent species used in this study. It is likely that the highly aggressive behavior of M. gilvus limits foraging activity of C. gestroi, N. luzonicus and M. losbanosensis around in-ground bait stations contributing to the low success of termite baits containing chitin synthesis inhibitors in the Philippines.  相似文献   

8.
The mirid bug Apolygus lucorum (Meyer-Dür) (Heteroptera: Miridae) is a severe pest of cotton and other crops in China. The feeding preferences of this pest are unclear due to its frequent movement among different host plants and the inconspicuous signs of its feeding. Here, we present results of a field trial that used direct observation of bug densities and a PCR-based molecular detection assay to detect plant DNA in bugs to explore relationships between A. lucorum population abundance and its feeding preference between two host plants, Humulus scandens (Loureiro) Merrill and Medicago sativa L. The field-plot samples showed that A. lucorum adults generally prefer flowering host plants. Its density was significantly higher on flowering H. scandens than on seedlings of M. sativa, and a similarly higher bug density was observed on flowering M. sativa than on seedlings of H. scandens. In the laboratory, we designed two pairs of species-specific primers targeting the trnL-F region for H. scandens and M. sativa, respectively. The detectability of plant DNA generally decreased with time post-feeding, and the half-life of plant DNA detection (DS50) in the gut was estimated as 6.26 h for H. scandens and 3.79 h for M. sativa with significant differences between each other. In mirid bugs exposed to seedlings of H. scandens and flowering M. sativa, the detection rate of M. sativa DNA was significantly higher than that of H. scandens. Meanwhile, in mirid bugs exposed to seedlings of M. sativa and flowering H. scandens, a significantly higher detection rate of H. scandens DNA was found. We developed a useful tool to detect the remaining plant food species specifically from the gut of A. lucorum in the current study. We provided direct evidence of its feeding preference between H. scandens and M. sativa at different growth stages, which strongly supported a positive correlation between population abundance and feeding preference of A. lucorum on different plants under field conditions. The findings provide new insights into the understanding of A. lucorum’s feeding preference, and are helpful for developing the strategies to control this pest.  相似文献   

9.
10.
Mucuna comprises 105 species with an overall pantropical distribution and is divided into three subgenera: M. subg. Mucuna, M. subg. Stizolobium and M. subg. Macrocarpa. Although phylogenetic studies have supported the occurrence of three main clades, evolutionary relationships among them are not fully resolved. The objective of this study was to examine pollen grain morphology from representatives of all three subgenera and map these onto the phylogenetic trees generated by analysis of other characters. Pollen grain surface, form, size, and aperture number were compared. A Bayesian inference tree using matK sequences was constructed. The results indicate that the representatives of M. subg. Macrocarpa have the smallest pollen grains in the genus (a synapomorphic character here identified for this subgenus) and that species of subgenus Mucuna (those with umbelliform inflorescences) have the largest pollen grains. Additional morphological diversity of the pollen grain surface was noted: reticulate and/or micro-reticulate (in all three subgenera), perforate, gemmate or verrucose (only in M. subg. Mucuna). For all studied taxa, the pollen grains are triaperturate, except for two species of M. subg. Mucuna, which have tetraperturate pollen. The phylogenetic tree obtained using the matK marker resolved M. subg. Stizolobium as the earliest diverging lineage in Mucuna. Based on this phylogeny, a reticulate ornamentation pattern of the pollen surface may represent the ancestral state for the genus, while the larger pollen size and the foraminate, gemmate, and verrucose ornamentations are derived characteristics within the genus. These putative derived ornamentations have been observed only in neotropical species.  相似文献   

11.
12.
Originally described as a monotypical genus with unclear taxonomic position from Sudan, Meroctenus Gemminger et Harold, 1868 is treated as a polytypical genus of the Selenophori genus group with two subgenera: Meroctenus s. str. and Xenodochus Andrewes, 1941, stat. n. (the latter was previously considered a distinct genus). Within Meroctenus, two species are recognized: M. (Meroctenus) crenulatus Chaudoir, 1843 (type species) and M. (M.) mediocris (Andrewes, 1936), comb, n., transferred to Meroctenus s. str. from Xenodochus. A new subspecies M. (M.) crenulatus orientalis subsp. n. is described from Pakistan. Diagnoses of the genus Meroctenus in new interpretation as well as of its two subgenera are discussed, and a taxonomic review of the subgenus Meroctenus s. str. with a key to the species and subspecies is provided. The following synonymy is proposed: Meroctenus Gemminger et Harold, 1868 = Paregaploa Müller, 1947, syn. n.; Meroctenus crenulatus (Chaudoir, 1843) = Egaploa (Paregaploa) conviva Müller, 1947, syn. n. Lectotypes are designated for Ctenomerus crenulatus Chaudoir, 1843 and Xenodus mediocris Andrewes, 1936.  相似文献   

13.
Alaimella cincta Cobb 1920 and Alaimella macramphis sp. n. are described and illustrated. Both the species were first recorded for the White Sea in northern Russia. A. cincta occurs in the shells of the agglutinated foraminiferan Reophax curtus, as well as freely in bottom sediments. A. macramphis sp. n. is described from a single male sampled from bottom sediments. A. macramphis sp. n. is distinguished from two previously known species of Alaimella (A. cincta Cobb 1920 and A. truncate Cobb 1920) by having a longer body, longer cephalic setae, and a wide amphid equal to the respective body diameter. The new species also differs from A. truncate by the distinct striation of the cuticular annulations. The Alaimella species are additionally characterized by having a posterior glandular widening of the esophagus. An emended diagnosis of the genus Alaimella Cobb 1920 and a key for species identification are provided.  相似文献   

14.
15.
Megoura crassicauda Mordvilko (Hemiptera: Aphididae) is a dominant aphid species found on Vicia sativa subsp. nigra (L.) Ehrh. (Fabaceae) in the spring. Worker ants of Formica japonica, the dominant ant species attracted to the extrafloral nectaries of V. s. nigra, often attack ladybirds (Coccinella septempunctata), which are aphid enemies. However, the workers of F. japonica do not attack or exclude M. crassicauda, the non-myrmecophilous aphid. It appears that the “bodyguard” retained by the plant guards the plant’s herbivore by attacking the herbivores’ enemies, rather than guarding the plant itself. The relationship between V. s. nigra and M. crassicauda was observed in the field to examine and evaluate the cost of parasitism. Parasitism by M. crassicauda delayed flower bud formation markedly in V. s. nigra but did not kill the plants. V. s. nigra plants that were parasitized showed a net bean production similar to that of the non-parasitized controls. The parasitism rate of M. crassicauda increased when extrafloral nectaries were used by F. japonica. These results may indicate that M. crassicauda provides V. s. nigra with benefits by preventing other serious disadvantages.  相似文献   

16.
Two new bristletail species, Allopsontus (Anisoptinus) nigrus sp. n. from Southeastern Kazakhstan and A. (Kaplinilis) abkhazicus sp. n. from Abkhazia, are described. A. nigrus sp. n. differs from the only other known species of the subgenus Anisoptinus, A. borgustani Kaplin 2015, in a number of characters, namely, in more rounded paired ocelli, an extended apical segment of the labial palpus, a long articulated ovipositor, and in the absence of short appressed pigmented setulae on the maxillary and labial palpi in males. A. abkhazicus sp. n. can be easily distinguished from all the other known species of the subgenus Kaplinilis by the absence of short appressed pigmented setulae on the maxillary and labial palpi in the males, the absence of a projection with numerous spiniform setae on the male fore femur, and in shorter male genital appendages. The ocellus of the male and female is 2.8-2.9 times as wide as long; the length to width ratio of the eye is 0.9-1.0; the ovipositor consists of 60 divisions.  相似文献   

17.
Based on light and scanning electron microscopical studies, a new nematode parasite, Pseudodelphis eleginopsis n. sp. (Dracunculoidea: Guyanemidae), is described from tissues behind the gills of the Patagonian blennie Eleginops maclovinus (Cuvier) (Perciformes: Eleginopsidae) off the Atlantic coast (San Matías and San José Gulfs) of Patagonia, Argentina. The new species is mainly characterised by the length of the body (males 10–13 mm, larvigerous females 31–59 mm), the number (14) and arrangement of cephalic papillae, the absence of a buccal capsule, the muscular to glandular oesophagus length ratio (1:3–4) of larvigerous females, the length of the spicules (48–63 µm) and the number (7 pairs) and arrangement of the caudal papillae in the male. Pseudodelphis eleginopsis n. sp. is the first species of this genus described from a marine fish in the Atlantic Ocean and the first known dracunculoid parasitising the fish host belonging to the family Eleginopsidae. As revealed by the examination of very young females of the new species, the female genital tract of Pseudodelphis spp. is monodelphic. The genus Syngnathinema Moravec, Spangenberg & Frasca, 2001 is considered a junior synonym of Pseudodelphis Adamson & Roth, 1990 and, consequently, S. californiense and S. chitwoodi are transferred to Pseudodelphis as P. californiensis (Moravec, Spangenberg & Frasca, 2001) n. comb. and P. chitwoodi (Moravec & Kuchta, 2013) n. comb., respectively. Two dracunculoid species, Pseudodelphis limnicola Brugni & Viozzi, 2006 and the previously established Philonema percichthydis Moravec, Urawa & Coria, 1997, both described from the same freshwater host species, Percichthys trucha (Valenciennes), in the same region (Patagonia), are considered to be identical; therefore, the valid name of this species is Pseudodelphis percichthydis n. comb. and P. limnicola becomes its junior synonym. A key to the species of Pseudodelphis is provided.  相似文献   

18.
19.
The geographic ranges, karyotypes, ecological preferences, and mitochondrial DNA polymorphism were analyzed to reveal the origin and taxonomic position of Agrodiaetus pljushtchi and related species of A. damone species group. According to the data obtained, the common ancestor of these species originated in Asia Minor in Late Pliocene, 1.2–1.8 million years ago. In Early Pleistocene (0.8–1.2 million years ago), a representative of this group migrated into the Crimea and gave rise to A. pljushtchi. Another branch originated from the common ancestor, which migrated into Central Asia and Siberia and gave rise to a variety of partly sympatric taxa. Recently, representatives of the Central Asian — Siberian lineage occupied Eastern Europe and approached the area of A. pljushtchi but did not overlap with it. The karyotype n = 67 is an apomorphy of the A. damone species complex. However, this karyotype is not species-specific and cannot be used to differentiate taxa within the complex. The similarity of karyotypes is thus not sufficient to consider A. pljushtchi and A. damone as conspecific taxa. The natural history data support the isolated position of A. pljushtchi, and phylogenetic analysis shows that A. pljushtchi and A. damone are not closely related.  相似文献   

20.
Five species of mouse or forest shrews (Myosorex) are endemic to South Africa, Lesotho and Swaziland, four of which (Myosorex varius, Myosorex cafer, Myosorex longicaudatus and Myosorex cf. tenuis) are associated with montane or temperate grassland, fynbos and/or forest habitats while a fifth (Myosorex sclateri) is associated with lowland subtropical forests. Due to their small size, specialised habitat, low dispersal capacity, high metabolism and sensitivity to temperature extremes, we predicted that, particularly for montane species, future climate change should have a negative impact on area of occupancy (AOO) and ultimately extinction risks. Species distribution models (SDMs) indicated general declines in AOO of three species by 2050 under the A1b and A2 climate change scenarios (M. cafer, M. varius, M. longicaudatus) while two species (M. sclateri and M. cf. tenuis) remained unchanged (assuming no dispersal) or increased their AOO (assuming dispersal). While temperate species such as M. varius appear to be limited by temperature maxima (preferring cooler temperatures), the subtropical species M. sclateri appears to be limited by temperature minima (preferring warmer temperatures). Evidence for declines in AOO informed the uplisting (to a higher category of threat) of the Red List status of four Myosorex species to either vulnerable or endangered as part of a separate regional International Union for Conservation of Nature (IUCN) Red List assessment.  相似文献   

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