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1.
Entomological Review - The type and other extensive material of Coprophilus (Zonyptilus) pennifer (Motschulsky, 1845) and some of its synonyms was examined. Coprophilus (Zonyptilus) marginalis...  相似文献   

2.
Gildenkov  M. Yu. 《Entomological Review》2020,100(7):1009-1019
Entomological Review - The type material of several synonyms of Coprophilus (Zonyptilus) pennifer (Motschulsky, 1845) is revised. Both Coprophilus (Zonyptilus) striatipennis (Eppelsheim, 1894) and...  相似文献   

3.
Sarcophaga (Sarcorohdendorfia) gracilior (Chen, 1975) is documented from specimens collected in Hubei Province, China, using morphological characters and wing interference patterns (WIPs). The female of S. (S.) gracilior is described for the first time, the male is redescribed, and both sexes are photographed. The distribution of the species is updated.  相似文献   

4.
Abstract. The fruit fly genus Ceratitis (Diptera: Tephritidae) comprises several important pest species attacking a wide range of unrelated fruits. In this paper the subgenus Ceratitis ( Pardalaspis ) Bezzi is revised. Ten species are recognized of which five are described as new: C.(P.)hamata sp.n., C.(P.)munroi sp.n., C.(P.)serrata sp.n., C.(P.)semipunctata sp.n. and C.(P.)zairensis sp.n. A key to both sexes is provided. All species are restricted to the Afrotropical Region and distributional and known host plant data are given.  相似文献   

5.
The ultrastructural organization of vitellogenesis of Plagiorchis elegans (Rudolphi, 1802), experimentally obtained from the golden hamster Mesocricetus auratus (Linnaeus, 1758), is described using transmission electron microscopy. This study is the first ultrastructural study of vitellogenesis in a member of the superfamily Plagiorchioidea. The four stages usually observed during vitellogenesis are described: stage I, cytoplasm of the vitellocytes mainly filled with ribosomes and few mitochondria; stage II, beginning of the synthetic activity; stage III, active synthesis of the shell globule clusters; stage IV, vitellocytes are filled with shell globule clusters and contain several lipid droplets, and glycogen granules are grouped around clusters and droplets. Vitellogenesis in P. elegans is compared with that of other Digenea. The differences among P. elegans and previously studied digeneans include, but are not limited to the occurrence of dense coiled endoplasmic reticulum saccules and the concentration of glycogen in the mesenchyme, which may be considered as a fifth stage of maturation of the vitelline glands. This peculiarity was not observed in all trematodes, which clearly indicates differences in the vitellogenesis in various digenean lineages at different stages of maturation of their vitelline cells.  相似文献   

6.
Genetic divergence and variability at 14 enzyme loci were examined in and between Italian populations of two edaphic Oribatid (Acarida, Oribatida) species, Steganacarus (Steganacarus) magnus (8 populations) and S. (S.) hirsutus (1 population). The seven populations belonging to S. (S.) magnus can be divided into two groups according to their phenotype, form anomala (A) (MON, ARG, AST, CDO) and form magna (M) (MAL, MAM, RIF) while another can be considered as hybrid between the two preceding groups (ZOC). Genetic identity (I) values between the S. (S.) magnus populations in spite of their morphological differences ranged from 0.977 to 1.000 showing the great genetic similarity of simple local populations while those of S. (S.) hirsutus indicated two distinct morphological species. The genetic distances between all the populations examined were very low despite the ecological differences and geographical distances between the collecting sites. Genetic variability estimates in all the populations of both species were very low when compared to those reported for most arthropods. Some explanatory considerations are suggested.  相似文献   

7.
Three genera of unstalked crinoids, Zenometra , Sarametra and Psathyrometra , formerly included in the subfamily Zenometrinae of the family Antedonidae, are removed and placed in a distinct family, the Zenometridae. Diagnostic features include a cavernous centrodorsal cavity, a complete basal circlet with a large central lumen and cirrus sockets with a concave fulcral bowl around the lumen. Sarametra nicobarica is synonymized under S. triserialis , which is redescribed in detail. Psathyrometra is redefined and includes only the species P. fragilis , P. congesta and P. bigradata , which are redescribed. P. erythrizon is synonymized under P. fragilis . The four other species formerly included in Psathyrometra are removed to Athrypsometra gen. n., retained in the Antedonidae. The other genera formerly included in the Zenometrinae are considered incertae sedis in the family Antedonidae pending detailed re-examination. Cladistic analysis using the antedonids, Poliometra prolixa (a former zenometrine) and Florometra serratissima , and the thalassometrid, Oceanometra annandalei , as outgroups produces the following tree: ( O. annandalei (( F. serratissima / P. prolixa )((( P. fragilis / P. congesta ) P. bigradata ) ( S. triserialis / Z. columnaris )))).  相似文献   

8.
Numerous individuals of the poorly known species Lecithostaphylus retroflexus (Zoogonidae) and Tergestia acanthocephala (Fellodistomidae) have been recovered from the teleost fish Belone belone gracilis from off the Scandola Nature Reserve, Western Mediterranean. They are redescribed, incorporating previously undescribed features: for L. retroflexus, a post-oral ring, a bipartite seminal vesicle, the shape of the excretory vesicle, the subterminal excretory pore and the flask-shaped gland-cells associated with the distinctly pedunculate ventral sucker; and for T. acanthocephala, the intestinal bifurcation in the forebody, necessitating its return to the genus Tergestia from Theledera. Additionally, T. acanthocephala is compared with T. laticollis from various species of Trachurus from the same geographical area.  相似文献   

9.
Peltidiidae (Copepoda, Harpacticoida) from the Weddell Sea (Antarctica)   总被引:1,自引:0,他引:1  
Alteutha polarsternae sp.n. is described and Eupelte villosa (Brady, 1910) is redescribed in detail. The distribution of both these species in the Weddell Sea is recorded.  相似文献   

10.
Molecular-mechanical simulations have been carried out on “mismatched base” analogs of the DNA double-helical structure d(CGCGAATTCGCG)2, in which the base pairs CG at the 3 and 10 positions have been replaced by CA, AG, TC, and TG base pairs, as well as an insertion analog in which an extra adenine has been incorporated into one strand of the above structure between bases 3 and 4. The results of these simulations (calculated relative stabilities, structures, and nmr ring-current shifts) have been compared with calorimetric and nmr data. The calculated relative stabilities of the double-helical parent dodecamer and the various “wobble” base pairs qualitatively correlate with the experimental melting temperatures. The base-pairing structure for the GT wobble pair is in agreement with that previously determined from nmr experiments. For the GA base pair, the structure with both bases anti has a slightly more favorable energy from base pairing and stacking than a structure with non-Watson-Crick H-bonding with adenine syn, in agreement with nmr experiments. The CA wobble base is calculated to favor an adenine 6NH2 …? cytosine N3 H-bond over cytosine 4NH2 …? adenine N1, again, in agreement with nmr experiments. There is no definitive experimental data on the TC base pair, but the existence of (somewhat long and weak) H-bonds involving cytosine 4NH2 …? thymine 4CO and cytosine N3 …? thymine HN3 seems reasonable. We find a structure in which the extra adenine base of the insertion analogs sits “inside” the double helix.  相似文献   

11.
Plethodontid salamanders of genus Bolitoglossa constitute the largest and most diverse group of salamanders, including around 20% of living caudate species. Recent studies have indicated the occurrence of five recognized species in the Brazilian Amazon Rainforest. We present here the first cytogenetic data of a Brazilian salamander, which may prove to be a useful by contribution to the cytotaxonomy of the genus. Specimens were collected near the “type” locality (Utinga, Belém, PA, Brazil). Chromosomal preparations from duodenal epithelial cells and testes were subjected to Giemsa staining, C-banding and DAPI/CMA3 fluorochrome staining. All specimens showed a karyotype with 13 bi-armed chromosome pairs (2n = 26). Nucleolar Organizer Regions, evidenced by CMA3, were located distally on the long arm of pair 7 (7q). DAPI+ heterochromatin was predominantly centromeric, with some small pericentromeric bands. Although the C-banding patterns of other Bolitoglossa species are so far unknown, cytogenetic studies conducted in other Plethodontid salamanders have demonstrated that pericentromeric heterochromatin is a useful cytological marker for identifying interspecific homeologies. Species diversification is usually accompanied by chromosomal changes. Therefore, the cytogenetic characterization of Bolitoglossa populations from the middle and western Brazilian Amazon Basin could identify differences which may lead to the identification of new species.  相似文献   

12.
The ultrastructure of the mature spermatozoon of the type genus of the Plagiorchiidae Plagiorchis elegans (Rudolphi, 1802), a parasite of the Golden hamster, Mesocricetus auratus is described. This study is the first ultrastructural study of the spermatozoon of a Plagiorchis, the second of a plagiorchiid species and only the third in the Plagiorchioidea. Previously data on spermatozoon ultrastructure existed only for the plagiorchiid Enodiotrema reductum and the omphalometrid Rubenstrema exasperatum. The mature spermatozoon of P. elegans exhibited the general pattern described in most digenean species, namely two axonemes of the 9 + “1” Trepaxonemata pattern, nucleus, mitochondria, external ornamentation of the plasma membrane, spine‐like bodies, and glycogen granules. However, the rather typical expansion of the plasma membrane is not found in P. elegans. Another peculiarity of the spermatozoon of P. elegans is the presence of a structure called thin cytoplasm termination. Spermatozoon ultrastructure of P. elegans is compared with that of E. reductum and R. exasperatum. Spermatozoon of P. elegans conforms to the general pattern described in E. reductum. Thus, this study further expands our knowledge on the spermatozoon ultrastructure among the members of the Plagiorchioidea, one of the most phylogenetically derived groups of the digenea. J. Morphol. 274:965–972, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

13.
The anatomy of the respiratory system of the savanna-zone African freshwater crab, Sudanonautes (Convexonautes) aubryi monodi [Balss, 1929], has been examined and has been found to be adapted for both aerial and aquatic gas exchange. The activities of the scaphognathites and the directions of flow of the ventilatory stream have been recorded in stressed, active and resting specimens during their exposure to a wide range of conditions from deep water to dry land.Ventilation of the branchial chambers during aquatic gas exchange in Sudanonautes kept in deep water is shown to consist of a rapid, predominantly forward water flow similar to that of fully-aquatic species. Ventilation of the branchial chambers during aerial gas exchange in Sudanonautes on land is shown to consist of a relatively slow forward air flow. This flow is continuous in post-operative crabs, pulsatile in active crabs and completely immobile in resting crabs.A second method of ventilation of the branchial chambers during aerial gas exchange is shown to consist of a pulsatile reversed air flow. This occurs (1) when Sudanonautes is kept in very shallow water and active or stressed; (2) when it has recently moved on to land; and (3) when it is completely immersed and exhibiting aerial gas exchange under water. The unusual phenomenon of aerial gas exchange under water is reported here for the first time in any species of crab.Bimodal ventilation of the branchial chambers occurs in stressed or active crabs partly immersed in shallow water. This consists of an alternation between forward water flow and reversed air flow.The morphology of the branchial chambers in Sudanonautes, and observational data on the patterns of ventilation of the branchial chambers, are discussed in relation to those described for other air-breathing decapod crustaceans.  相似文献   

14.
Callichthyids take a basal position in the loricarioid evolutionary lineage leading up to an algae scraping feeding mechanism in the loricariid family. Therefore, the study of the morphology and development of a callichthyid representative would contribute to a better knowledge on the differences in cranial morphology and their impact on feeding ecology within this superfamily. Therefore, development in the chondrocranium of Corydoras aeneus was studied based on 22 cleared and stained specimens and 6 series of serial sections. The latter sections were also digitized and used for 3D reconstructions. Development overall follows the typical siluriform trends in chondrocranial development. Even the low complexity of the chondrocranium at hatching fits the trend observed in other siluriforms, although other studies showed loricarioid hatchlings to generally show more complex chondrocrania. In contrast to other catfish, in C. aeneus, the notochord was never found to protrude into the hypophyseal fenestra. In addition, also differing from other siluriforms, a commissura lateralis is present, a state also reported for Ancistrus cf. triradiatus (Geerinckx et al., [2005] J Morphol 266:331-355). The splanchnocranium again has the typical siluriform shape during its ontogeny, with the presence of a compound hyosymplectic-pterygoquadrate plate, although not fused to the neurocranium or interhyal at any time during ontogeny, a state described earlier for Callichthys callichthys (Hoedeman, [1960a] Bull Aquat Biol 1:73-84; Howes and Teugels, [1989] J Zool Lond 219:441-456). The most striking difference found in comparison to other catfishes, however, involves thebranchial basket, which arises as a single element with a further differentiation from the middle arches on in both a rostral and caudal direction.  相似文献   

15.
Ostracod association from the Upper Triassic (Tropites dilleri zone of the Carnian stage) of the sedimentary succession (Mufara Formation) exposed along the east side of Monte Scalpello (Catenanuova, central eastern Sicily) has been studied for the first time. The specimens, silicified, are rare but well preserved and often consist of complete carapaces. They belong to eight families: Healdiidae, Cavellinidae, Bairdiidae, Acratiidae, Bythocyprididae, Pontocyprididae, Judahellidae, Glorianellidae. Twenty-three taxa have been listed; the family Bairdiidae is the most represented among all the others with fifteen species. Four species are new: Bairdia scaliae n. sp., Acratia maugerii n. sp., “Anchistrocheles” gemmellaroi n. sp. and Judahella? montanarii n. sp. Other species are left in open nomenclature because of the lack of specimens.  相似文献   

16.
Climbing perches use the tail for forward propulsion when on land. The spiny gill covers are used to obtain purchase on the substratum. Unusually amongst teleosts, the opercular and subopercular bone are not bound strongly together into a single operculum. Instead they are joined only by a thin, flexible membrane, so that the fish has two sections of the gill cover hinged separately; the opercular on the suspensorium and the subopercular on the rearmost part of the lower jaw. The gill covers open very widely and the subopercular rotates ventrally as well as laterally. Two modes of locomotion are employed. Usually Anabus adopts a near-upright posture and alternately drives the left and right spiny suboperculars into the substratum, using the tail to vault over the subopercular (which acts in the manner of a short vaulting pole). During vigorous movement the fish may leave the substratum altogether during the vault. Fatigued fish, or fish which have fallen during climbing, move on their sides, using the tail for propulsion and a single spiny opercular which is repeatedly driven into the substratum. Maximum speeds observed on land corresponded to 1.8 body lengths S?1. No evidence of involvement of the pelvic fins in locomotion was obtained; the pectorals seemed only to help in tilting the head from side to side and did not contribute significantly to forward propulsion. On mud and tree bark the fish were laterally unstable, often resting on their sides. Grassy substrata provided support and permitted a more upright posture. Slope climbing ability was restricted to 25° when climbing tree bark and 30° when climbing grass. Coupled with lateral instability these observations disqualify the species from any tree-climbing capacity. Anabas can climb vertical obstacles of at least half body length in height by pushing the head against the obstacle, using the spiny gill covers for purchase until one or other subopercular hooks over the top of the barrier. The subopercular is then used as a fulcrum for an upwards vault to clear the obstacle.  相似文献   

17.
The lectotype specimen of Bryconamericus rubropictus (Berg) and its designation have remained imprecisely documented since its publication. The lack of a photograph or an unambiguous illustration, correct size, inaccurate labelling, and proper specimen separation has led to an uncertainty about the identity and nomenclatural status of the lectotype. We recovered and provided detailed morphological data on the specimen that must be recognised as the lectotype. This contribution brings stability and clarity on the nomenclatural status of the species and its type material.  相似文献   

18.
19.
Koen Martens 《Hydrobiologia》1991,218(2):127-131
The male of Sclerocypris tuberculata (Methuen), thus far unknown, is here described. Relying on the morphology of the copulatory appendages and of the prehensile palps, it appears that this taxon belongs to a separate species group, together with S. zelaznyi and perhaps also S. sarsi. There are some interesting sexual dimorphic characters in the valve morphology: males have shorter valves with a dorsal margin which runs nearly parallel to the ventral one (more elongated valves with sloping dorsal margin in females) and there is lobe-like projection of the valve margin on the ventro-caudal corner of the LV in females which is lacking in the male. Furthermore, the female genital region has a very aberrant morphology, and all specimens from the present collection possess the tuberculated and noded valves.  相似文献   

20.
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