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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.
Dirk Brandis 《Hydrobiologia》2001,452(1-3):89-100
The Himalayas are known to be a geologically young and dynamic mountain range hosting an endemic flora and fauna. To date, for freshwater crabs, one endemic subgenus within the genus Potamon, Potamon (Himalayapotamon) Pretzmann, 1966, has been described from the Himalayas. This subgenus includes two species, Potamon atkinsonianum (Wood-Mason, 1871) and Potamon emphysetum (Alcock, 1909). The taxonomic position of these two species is reconsidered. The subgenus Himalayapotamon is raised to generic level and its systematic and zoogeographic position is discussed. Based mainly on the morphology of the male copulatory system, Himalayapotamon belongs to the family Potamidae. It is more related to the Eurasian genus Potamon Savigny, and is distinct from the South-East Asian genus Potamiscus as well as from the Indian freshwater crabs of the family Gecarcinucidae. Zoogeographically Himalayapotamon appears to be an endemic genus related to Potamon, both genera presumably being isolated during the Miocene when the Gangetic waters were separated from the western Eurasian river systems. Further speciation occurred during glacial periods.  相似文献   

4.
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   

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Plagiorhynchus (Prosthorhynchus) cylindraceus (Goeze, 1782) Schmidt and Kuntz, 1966, usually parasitic in passerine birds, is here reported to be found encysted in the peritoneum of the bandicoot Isoodon obesulus from Tasmania. Specimens recovered from the bandicoot Perameles gunnii, also collected from Tasmania, are the first reported from the intestine of a mammal. The origin of P. cylindraceus infection in Australian hosts is discussed.  相似文献   

8.
During spiralian development, the first pair of nephridia forms anterior to the mouth. Each organ consists of a few cells, which is characteristic for spiralian larvae. In nemerteans, one of the unambiguously spiralian taxa, so far protonephridia, has been reported only in advanced pilidium larvae, where they likely persist as juvenile and adult nephridia. These organs have not been recorded in larvae of the basally branching nemertean taxa. In search for these organs, we examined the ultrastructure of pelagic planuliform larvae of the palaeonemerteans Carinoma mutabilis and Cephalothrix (Procephalothrix) filiformis. In both species, a pair of protonephridia is located at the level of the stomodaeum. Each protonephridium of C. mutabilis consists of two terminal cells, two duct cells and one nephropore cell, while that of C. filiformis consists of three terminal cells, three duct cells and one nephropore cell. In C. mutabilis and in C. filiformis, all terminal cells contribute to forming a compound filtration structure. In both species, the protonephridia seem to develop subepidermally, since in C. filiformis, the nephropore cells pierce the larval epidermis and in C. mutabilis, the nephropores are initially covered by the binucleated multiciliated trophoblast cells. On the fifth day, these cells degenerate, so that the protonephridium becomes functional. The occurrence of protonephridia in the larvae of both paleonemertean species is in accordance with the hypothesis that a common ancestor of Nemertea and Trochozoa had a larval stage with a pair of protonephridia. This does not contradict previous hypotheses on placing the Nemertea as an ingroup of the Trochozoa or Spiralia (= Lophotrochozoa). Whether these protonephridia are restricted to the larval phase or whether they are transformed into the adult protonephridia, like those of the pilidium larva, remains to be answered.  相似文献   

9.
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   

10.
The structure, stability, and the IR, and EPR spectroscopic properties of bis(methoxyacetato)diaquo-copper(II) were studied both experimentally using FT-IR and theoretically using B3LYP/6-31G**, B3LYP/6-311G, BWP91/6-31G** methods. The same approaches were used to calculate the harmonic frequencies and to compare them to the experimental solid state values. The g-tensors are calculated using the NMR/GIAO computational method.  相似文献   

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The rich rissooidean fauna of Balkan Peninsula, the history of which began at the time of Paratethys, is not sufficiently studied yet. It includes, among others, many taxa of minute gastropods with a moderately high-spired shell, a penis with a double lobe on its left edge and female reproductive organs with a loop of coiled oviduct and two receptacles, the morphology of which does not allow for a certain determination. In the article we deal with five such populations. We describe the shell, radula, soft part morphology and anatomy of the reproductive organs of Grossuana codreanui (Grossu, 1946) from its type locality at the Techirghiol Lake, Dobrogea, Romania. The species is compared molecularly (fragments of two genes: mitochondrial CO1 and ribosomal 18 S) with G. codreanui from Bulgaria, G. serbica (Radoman, 1973) from its type locality, Belgrandiella haesitans (Westerlund, 1881) from the spring of the Louros River, and Orientalina delphica (Radoman, 1973) from the spring Kastalia at Delphi. All the five populations were found to belong to the genus Grossuana: G. codreanui, G. serbica, G. vurliana (Radoman, 1966), and G. dephica (Radoman, 1973), respectively. We applied 12 morphological characters of Grossuana and 17 other rissooidean genera (mostly of the Hydrobiidae s. stricto) to infer phylogeny, which has shown the position of the genus within the Hydrobiidae s. stricto, most close to Orientalina. All the molecular data confirm that Grossuana is a distinct genus belonging to the Hydrobiidae, Horatiinae, whose closest relatives are Belgrandia, Orientalina and Horatia. Handling editor: C. Sturmbauer  相似文献   

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The development of the male genital ducts in Clitellio arenarius, Tubificoides benedii, Heterochaeta costata (Tubificidae) and Stylaria lacustris (Naididae) is studied with the purpose of investigating the homologies between different parts of the ducts. In both Tubificidae and Naididae, the male duct comprises a funnel, a vas deferens and an atrium. There may also be a prostate gland (diffuse or compact) in association with the duct. The funnel and vas deferens, in all four species, originate from the peritoneal (mesodermal) cells in the posterior septa in the testes segment, whereas the atrium develops from an epidermal (ectodermal) invagination. The prostate glands have different origins in different taxa; in S. lacustris it differentiates from the peritoneal (mesodermal) cells surrounding the atrium, but in H. costata and T. benedii it develops by a multiplication of the atrial (ectodermal) cells; C. arenarius lacks a prostate gland. The development of the spermathecae and the female duct is also studied. The spermatheca is an epidermal invagination. The female duct is of mesodermal origin. However, the position of the duct differs; in S. lacustris the female duct is lateral and the pore is in the ovarian segment, while in the tubificids studied the duct is ventral with the pore in the segment behind the one containing the ovary.  相似文献   

16.
Parasitic protozoans, identified as Haemogregarina aeglefini (Henry), were found in erythrocytes of two gadiform fish, Melanogrammus aeglefinus (haddock) and Gaidropsaurus cimbrius (four-bearded rockling). The latter species also harboured trypanosomes in its blood plasma, and a kind of intracellular parasite-like inclusions in macrophages of the spleen, the pronephros and the liver. Most specimens of Gaidropsaurus cimbrius had leeches ( Callobdella nodulifera ) attached to the skin. A remarkable abundance of blood leucocytes noted in Gaidropsaurus cimbrius may be a response to haematozoan infections.  相似文献   

17.
The objective of this study was to determine the basic population‐specific parameters necessary for fish stock assessment in the Gulf of Annaba and to compare these with data from other Mediterranean regions. Black sea bream Spondyliosoma cantharus (Linnaeus, 1758) (N = 501) were collected monthly from January to December 2008 along the Algerian eastern coasts. More than 22 fish were collected each month and ranged in size from 13.4 to 40 cm total length, weighing from 36 to 1080 g eviscerated weight. Biological sampling included weighing and measuring the fish, gonad weighing, sex and maturity stage determination, and age estimation through otolith readings. Validity of the otolith readings for estimating age and growth was supported using the back‐calculation method. Estimated parameters of the von Bertalanffy model are: L = 33.54 cm, W = 633.46 g, = 0.52 year?1 and to = ?0.04 year. The growth performance index (φ) is: 2.76. The length‐weight relationship is: EW = 4.4.10?6 TL3.23. The spawning period occurred from February to May, while the gamete emission peaked in April. Females reached sexual maturity at 19.3 cm (2 years) and males at 21.3 cm (3 years). Sexual inversion occurs at approximately 24.3 cm. Spondyliosoma cantharus was characterized as being a protogynic hermaphrodite.  相似文献   

18.
Tin-119 NMR data indicate that the tin atom in (CH3)2Sn(S2COC2H5)2 is four co-ordinated in dichloromethane solution. However, single crystal X-ray analysis shows the tin atom to be six co-ordinated in the solid state in which the bidentate xanthate ligands display gross asymmetry in their mode of co-ordination to the tin. The crystals are molecular and there is no association between neighbouring molecules. The unit cell of Me2Sn(exa)2 is orthorhombic, Pnma, a = 14.165(1), b = 7.675(9), c = 13.977(2) Å with Z = 4. The structure was refined by conventional least squares methods with final R 0.041 and Rw 0.043 for 1229 unique reflections with 1 ? 2σ(I).  相似文献   

19.
Secoisolariciresinol diglucosides (SDGs) (S,S)-SDG-1 (major isomer in flaxseed) and (R,R)-SDG-2 (minor isomer in flaxseed) were synthesized from vanillin via secoisolariciresinol (6) and glucosyl donor 7 through a concise route that involved chromatographic separation of diastereomeric diglucoside derivatives (S,S)-8 and (R,R)-9. Synthetic (S,S)-SDG-1 and (R,R)-SDG-2 exhibited potent antioxidant properties (EC50 = 292.17 ± 27.71 μM and 331.94 ± 21.21 μM, respectively), which compared well with that of natural (S,S)-SDG-1 (EC50 = 275.24 ± 13.15 μM). These values are significantly lower than those of ascorbic acid (EC50 = 1129.32 ± 88.79 μM) and α-tocopherol (EC50 = 944.62 ± 148.00 μM). Compounds (S,S)-SDG-1 and (R,R)-SDG-2 also demonstrated powerful scavenging activities against hydroxyl [natural (S,S)-SDG-1: 3.68 ± 0.27; synthetic (S,S)-SDG-1: 2.09 ± 0.16; synthetic (R,R)-SDG-2: 1.96 ± 0.27], peroxyl [natural (S,S)-SDG-1: 2.55 ± 0.11; synthetic (S,S)-SDG-1: 2.20 ± 0.10; synthetic (R,R)-SDG-2: 3.03 ± 0.04] and DPPH [natural (S,S)-SDG-1: EC50 = 83.94 ± 2.80 μM; synthetic (S,S)-SDG-1: EC50 = 157.54 ± 21.30 μM; synthetic (R,R)-SDG-2: EC50 = 123.63 ± 8.67 μM] radicals. These results confirm previous studies with naturally occurring (S,S)-SDG-1 and establish both (S,S)-SDG-1 and (R,R)-SDG-2 as potent antioxidants and free radical scavengers for potential in vivo use.  相似文献   

20.
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   

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