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1.
Two new species Dacne (Xenodacne) tangliangi sp. n. andDacne (Xenodacne) hujiayaoi sp. n. are described from China. A key to Chinese species and subspecies of genus Dacne Latreille is provided.  相似文献   

2.
Here we describe and illustrate a new parasitoid wasp species, Lathrolestes gauldi sp. n. from the lowland rainforest of eastern Ecuador and provide a key to the Neotropical species of the genus. This is the first record of the subfamily Ctenopelmatinae from Ecuador.  相似文献   

3.
A new species of the genus Himertosoma Schmiedeknecht, Himertosoma kuslitzkii sp. n., was discovered in Amamioshima Island, the Ryukyus. This new species resembles two Oriental species, Himertosoma philippense Chandra & Gupta and Himertosoma townesi Chandra & Gupta, in the colour pattern of the head and metasoma, number of flagellomeres, and the relatively slender first metasomal tergite, but can easily be distinguished from them by the nearly evenly punctate propodeum, different length/width ratio of the first metasomal tergite, different length of the ovipositor sheath, tricoloured mesosoma, and the whitish band along the posterior margin of the second and following metasomal tergites. A key to the Palaearctic and Oriental species of Himertosoma is also provided.  相似文献   

4.
Paraportanus longispinus,, a new leafhopper species from Roraima and Amazonas States, North Brazil, is described and illustrated. The new species can be recognized by the male genital features, especially the distal third of ventral margin of the pygofer with a dentiform short process; plates distinctly longer than pygofer, extending posteriorly beyond pygofer by approximately 1/3 of their length and aedeagus with one pair of spiniform process long crossed and directed ventrally. A checklist and key to males of all known Paraportanus species is provided.  相似文献   

5.
Calliostoma tupinamba isa new species from Southeastern Brazil, ranging from southern Rio de Janeiro to northern São Paulo, and found only on coastal islands, on rocks and sessile invertebrates at 3 to 5 meters of depth. Shell and soft part morphology is described here in detail. Calliostoma tupinamba is mainly characterized by a depressed trochoid shell; eight slightly convex whorls; a sharply suprasutural carina starting on the third whorl and forming a peripheral rounded keel; and a whitish, funnel-shaped and deep umbilicus, measuring about 5%–10% of maximum shell width. Calliostoma tupinamba resembles Calliostoma bullisi Clench & Turner, 1960 in shape, but differs from it in being taller and wider, having a smaller umbilicus and lacking a strong and large innermost spiral cord at its base. Finally, an identification key of Brazilian Calliostoma species is presented.  相似文献   

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The New World species of Polytrichophora Cresson and Facitrichophora new genus, are revised. Fifteen new species are described (type locality in parenthesis): Facitrichophora atrella sp. n. (Costa Rica. Guanacaste: Murciélago [10°56.9''N, 85°42.5''W; sandy mud flats around mangrove inlet]), Facitrichophora carvalhorum sp. n. (Brazil. São Paulo: Praia Puruba [23°21''S, 44°55.6''W; beach]), Facitrichophora manza sp. n. (Trinidad and Tobago. Trinidad. St. Andrew: Lower Manzanilla (12 km S; 10°24.5''N, 61°01.5''W), bridge over Nariva River), Facitrichophora panama sp. n. (Panama. Darien: Garachine [8°04''N, 78°22''W]), Polytrichophora adarca sp. n. (Barbados. Christ Church: Graeme Hall Nature Sanctuary [13°04.2''N, 59°34.7''W; swamp]), Polytrichophora arnaudorum sp. n. (Mexico. Baja California. San Felipe [31°01.5''N, 114°50.4''W]), Polytrichophora barba sp. n. (Cuba. Sancti Spiritus: Topes de Collantes [21°54.4''N, 80°01.4''W, 670 m]), Polytrichophora flavella sp. n. (Peru. Madre de Dios: Rio Manu, Pakitza [11°56.6''S, 71°16.9''W; 250 m]), Polytrichophora marinoniorum sp. n. (Brazil. Paraná: Antonina [25°28.4''S, 48°40.9''W; mangal]), Polytrichophora rostra sp. n. (Peru. Madre de Dios: Rio Manu, Pakitza [11°56.6''S, 71°16.9''W; 250 m]), Polytrichophora sinuosa sp. n. (Trinidad and Tobago. Trinidad. St. Andrew: Lower Manzanilla [12 km S; 10°24''N, 61°02''W]), Polytrichophora mimbres sp. n. (United States. New Mexico. Grant: Mimbres River [New Mexico Highway 61 & Royal John Mine Road; 32°43.8''N, 107°52''W; 1665 m]), Polytrichophora salix sp. n. (United States. Alaska. Matanuska-Susitna: Willow Creek [61°46.1''N, 150°04.2''W; 50 m]), Polytrichophora sturtevantorum sp. n. (United States. Tennessee. Shelby: Meeman Shelby State Park [Mississippi River; 35°20.4''N, 90°2.1''W; 98 m]), Polytrichophora prolata sp. n. (Belize. Stann Creek: Cockscomb Basin Wildlife Sanctuary [16°45''N, 88°30''W]). All known New World species of both genera are described with an emphasis on structures of the male terminalia, which are fully illustrated. Detailed locality data and distribution maps for all species are provided. For perspective and to facilitate recognition, the tribe Discocerinini is diagnosed and a key to included genera is provided.  相似文献   

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In the Brazilian Amazon, American tegumentary leishmaniasis (ATL) is endemic and presents a wide spectrum of clinical manifestations due, in part, to the circulation of at least seven Leishmania species. Few reports of Leishmania (Viannia) naiffi infection suggest that its occurrence is uncommon and the reported cases present a benign clinical course and a good response to treatment. This study aimed to strengthen the clinical and epidemiological importance of L. (V.) naiffi in the Amazon Region (Manaus, state of Amazonas) and to report therapeutic failure in patients infected with this species. Thirty Leishmania spp samples isolated from cutaneous lesions were characterised by multilocus enzyme electrophoresis. As expected, the most common species was Leishmania (V.) guyanensis (20 cases). However, a relevant number ofL. (V.) naiffi patients (8 cases) was observed, thus demonstrating that this species is not uncommon in the region. No patient infected withL. (V.) naiffi evolved to spontaneous cure until the start of treatment, which indicated that this species may not have a self-limiting nature. In addition, two of the patients experienced a poor response to antimonial or pentamidine therapy. Thus, either ATL cases due to L. (V.) naiffi cannot be as uncommon as previously thought or this species is currently expanding in this region.  相似文献   

11.
Male gyro (Gy) mice, which have an X chromosomal deletion inactivating the SpmS and Phex genes, were found to be profoundly hearing impaired. This defect was due to alteration in polyamine content due to the absence of spermine synthase, the product of the SpmS gene. It was reversed by breeding the Gy strain with CAG/SpmS mice, a transgenic line that ubiquitously expresses spermine synthase under the control of a composite cytomegalovirus-IE enhancer/chicken β-actin promoter. There was an almost complete loss of the endocochlear potential in the Gy mice, which parallels the hearing deficiency, and this was also reversed by the production of spermine from the spermine synthase transgene. Gy mice showed a striking toxic response to treatment with the ornithine decarboxylase inhibitor α-difluoromethylornithine (DFMO). Within 2–3 days of exposure to DFMO in the drinking water, the Gy mice suffered a catastrophic loss of motor function resulting in death within 5 days. This effect was due to an inability to maintain normal balance and was also prevented by the transgenic expression of spermine synthase. DFMO treatment of control mice or Gy-CAG/SpmS had no effect on balance. The loss of balance in Gy mice treated with DFMO was due to inhibition of polyamine synthesis because it was prevented by administration of putrescine. Our results are consistent with a critical role for polyamines in regulation of Kir channels that maintain the endocochlear potential and emphasize the importance of normal spermidine:spermine ratio in the hearing and balance functions of the inner ear.Polyamines are essential for viability in mammals. Knockouts of the genes for ornithine decarboxylase and S-adenosylmethionine decarboxylase, which are enzymes needed for the synthesis of putrescine, spermidine, and spermine, are lethal at early stages of embryonic development (1, 2). There is convincing evidence that the formation of hypusine in eIF5A, which requires spermidine as a precursor, is essential for eukaryotes (3). However, the function(s) of spermine is not so well established. Yeast mutants with inactivated spermine synthase grow at a normal rate (4). Mammalian cells in culture also grow normally in the presence of inhibitors of spermine synthase (5) or after inactivation of the spermine synthase gene (SpmS) (68). Inactivation of both of the genes that were originally described as encoding spermine synthases in plants leads to profound developmental defects (911), but recently it was discovered that one of these genes actually encodes a thermospermine synthase, and it appears that the lack of thermospermine may be responsible for these defects (12).In contrast, spermine is clearly required for normal development in mammals. The rare human Snyder-Robinson syndrome is caused by mutations in SpmS located in the X chromosome that drastically reduces the amount of spermine synthase (13, 14). This leads to mental retardation, hypotonia, cerebellar circuitry dysfunction, facial asymmetry, thin habitus, osteoporosis, and kyphoscoliosis. Male mice, which have an X chromosomal deletion that includes SpmS and have no detectable spermine synthase activity, do survive but are only viable on the B6C3H background (1517). This mouse strain having an X-linked dominant mutation was isolated from a female offspring of an irradiated mouse and was termed gyro (Gy)2 based on a circling behavior pattern in affected males (18). Subsequent studies have shown that the Gy mice have a deletion of part of the X chromosome that inactivates both Phex, a gene that regulates phosphate metabolism, and SpmS (16, 19). The lack of SpmS causes a total absence of spermine (6, 7, 15, 16). Such Gy mice suffer from hypophosphatemia, have a greatly reduced size, sterility, and neurological abnormalities, and have a short life span (6, 16, 18). All of these changes except the hypophosphatemia are reversed when spermine synthase activity is restored (20).The original characterization of Gy mice also reported preliminary indications that these mice had hearing defects lacking the Preyer reflex (21, 22). This is of particular interest in the context of polyamine metabolism because a drug, α-difluoromethylornithine (DFMO, Eflornithine), that targets ornithine decarboxylase has been shown to cause occasional hearing loss in some patients (2326). Although DFMO was ineffective for cancer treatment, it is an extremely promising agent for cancer chemoprevention (27, 28). When combined with sulindac, DFMO treatment produced a substantial reduction in the recurrence of colorectal adenomas in a large clinical trial (27). DFMO is a major drug for the treatment of African sleeping sickness caused by Trypanosoma brucei (29, 30). It is also used as a topically applied cream for treatment of unwanted facial hair in women (31, 32). DFMO is generally well tolerated even at high doses, but reversible hearing loss has been reported in multiple clinical trials (25, 33), and a rarer irreversible defect has also been reported (34). These side effects are not observed at lower doses of DFMO (26, 27).Ototoxicity has been demonstrated to occur in experimental animals treated with DFMO including rats (35), guinea pigs (36), gerbils (37), and mice (38). Using immunohistochemistry, a high level of ornithine decarboxylase was observed in the inner ear of the rat, with the highest in the organ of Corti and lateral wall followed by the cochlear nerve (39). Measurements of polyamines in the relevant structures are very difficult due to the small amount of tissue available, but as expected, DFMO treatment reduced polyamine levels and ornithine decarboxylase activity in the inner ear of the guinea pig (36). A plausible explanation for the importance of polyamines in auditory physiology is based on their well documented role as regulators of potassium channels (38). The inward rectification of Kir channels is caused by blockage of the outward current by polyamines (4042). Studies of the cloned mouse cochlear lateral wall-specific Kir4.1 channel showed that inward rectification was reduced and that there was a marked reduction in endocochlear potential (EP). It was proposed that DFMO treatment increases the outward Kir4.1 current, resulting in a drop in EP (38).In the experiments reported here, we have studied in more detail the role of polyamines in auditory physiology using Gy mice and crosses of these mice with transgenic CAG/SpmS mice (43). These mice express spermine synthase under the control of a composite cytomegalovirus-IE enhancer/chicken β-actin promoter, which was designed to provide ubiquitous expression (4446). Assays of the spermine synthase activity in CAG/SpmS line 8 confirmed that there was a high level of expression of the transgene in many different organs and that this level was maintained for at least 1 year (43). Our studies confirm that Gy mice are totally deaf and that this condition is reversed by the expression of the SpmS gene. These changes are due to a virtually complete loss of the EP in the Gy mice. We have also examined the effect of DFMO on the Gy mice. Unexpectedly, it was found that these mice show a rapid and profound toxicity to this drug, leading to death within a few days. Within 5 days of exposure to DFMO in the drinking water, the DFMO-treated mice suffered a catastrophic loss of balance due to inner ear effects. This toxicity was also prevented by the transgenic expression of spermine synthase in the Gy background.  相似文献   

12.
A new species of Profundulus, Profundulus kreiseri (Cyprinodontiformes: Profundulidae), is described from the Chamelecón and Ulúa Rivers in the northwestern Honduran highlands. Based on a phylogenetic analysis using cytochrome b and the presence of synapomorphic characters (dark humeral spot, a scaled preorbital region and between 32-34 vertebrae), this new species is placed in the subgenus Profundulus, which also includes Profundulus (Profundulus) oaxacae, Profundulus (Profundulus) punctatus and Profundulus (Profundulus) guatemalensis. Profundulus kreiseri can be distinguished from other members of the subgenus Profundulus by having less than half of its caudal fin densely scaled. Profundulus kreiseri can further be differentiated from Profundulus (Profundulus) oaxacae and Profundulus (Profundulus) punctatus by the absence of rows of dark spots on its flanks. The new species can further be differentiated from Profundulus (Profundulus) guatemalensis by the presence of fewer caudal- and pectoral-fin rays. The new species is distinguished from congeners of the profundulid subgenus Tlaloc (viz., Profundulus (Tlaloc) hildebrandi, Profundulus (Tlaloc) labialis, Profundulus (Tlaloc) candalarius and Profundulus (Tlaloc) portillorum) by having a scaled preorbital region and a dark humeral spot. Profundulus kreiseri and Profundulus portillorum are the only two species of Profundulus that are endemic to the region south of the Motagua River drainage in southern Guatemala and northwestern Honduras.  相似文献   

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The relationship between microevolution and macroevolution is a central topic in evolutionary biology. An aspect of this relationship that remains very poorly studied in modern evolutionary biology is the relationship between within‐species geographic variation and among‐species patterns of trait variation. Here, we tested the relationship between climate and morphology among and within species in the salamander genus Plethodon. We focus on a discrete colour polymorphism (presence and absence of a red dorsal stripe) that appears to be related to climatic distributions in a common, wide‐ranging species (Plethodon cinereus). We find that this trait has been variable among (and possibly within) species for >40 million years. Furthermore, we find a strong relationship among species between climatic variation and within‐species morph frequencies. These between‐species patterns are similar (but not identical) to those in the broadly distributed Plethodon cinereus. Surprisingly, there are no significant climate–morphology relationships within most other polymorphic species, despite the strong between‐species patterns. Overall, our study provides an initial exploration of how within‐species geographic variation and large‐scale macroevolutionary patterns of trait variation may be related.  相似文献   

16.
Receptor-mediated activation of heterotrimeric G proteins leading to dissociation of the Gα subunit from Gβγ is a highly conserved signaling strategy used by numerous extracellular stimuli. Although Gβγ subunits regulate a variety of effectors, including kinases, cyclases, phospholipases, and ion channels (Clapham, D.E., and E.J. Neer. 1993. Nature (Lond.). 365:403–406), few tools exist for probing instantaneous Gβγ-effector interactions, and little is known about the kinetic contributions of effectors to the signaling process. In this study, we used the atrial muscarinic K+ channel, which is activated by direct interactions with Gβγ subunits (Logothetis, D.E., Y. Kurachi, J. Galper, E.J. Neer, and D.E. Clap. 1987. Nature (Lond.). 325:321–326; Wickman, K., J.A. Iniguez-Liuhi, P.A. Davenport, R. Taussig, G.B. Krapivinsky, M.E. Linder, A.G. Gilman, and D.E. Clapham. 1994. Nature (Lond.). 366: 654–663; Huang, C.-L., P.A. Slesinger, P.J. Casey, Y.N. Jan, and L.Y. Jan. 1995. Neuron. 15:1133–1143), as a sensitive reporter of the dynamics of Gβγ-effector interactions. Muscarinic K+ channels exhibit bursting behavior upon G protein activation, shifting between three distinct functional modes, characterized by the frequency of channel openings during individual bursts. Acetylcholine concentration (and by inference, the concentration of activated Gβγ) controls the fraction of time spent in each mode without changing either the burst duration or channel gating within individual modes. The picture which emerges is of a Gβγ effector with allosteric regulation and an intrinsic “off” switch which serves to limit its own activation. These two features combine to establish exquisite channel sensitivity to changes in Gβγ concentration, and may be indicative of the factors regulating other Gβγ-modulated effectors.  相似文献   

17.
Duvalius (sg. Neoduvalius) gejzadunayi sp. n. from Pećina u Dubokom potoku cave ( Donje Biševo village near Rožaje, Montenegro), the first known representative of this subgenus from the territory of Montenegro is described, illustrated and compared with the related species of the subgenus Neoduvalius Müller, 1913. This new species is characterised by depigmented, medium sized body, totally reduced eyes, deep and complete frontal furrows, 3–4 pairs of discal setae in third elytral stria, as well as by the shape of aedeagus. Data on the distribution and the ecology of this remarkable species, as well as a check-list of the subgenus Neoduvalius are also provided. Recently described genera Serboduvalius Ćurčić, S. B. Pavićević & Ćurčić, B.P.M., 2001, Rascioduvalius Ćurčić, S. B. Brajković, Mitić & Ćurčić, B.P.M., 2003, Javorella Ćurčić, S. B. Brajković, Ćurčić, B.P.M. & Mitić, 2003 and Curcicia Ćurčić, S. B. & Brajković, 2003 are regarded as junior synonyms of the genus Duvalius Delarouzée.  相似文献   

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What structures the organization of mixed‐species bird flocks, so that some ‘nuclear’ species lead the flocks, and others follow? Previous research has shown that species actively listen to each other, and that leaders are gregarious; such gregarious species tend to make contact calls and hence may be vocally conspicuous. Here we investigated whether vocal characteristics are associated with leadership, using a global dataset of mixed‐species flock studies and recordings from sound archives. We first asked whether leaders are different from following or occasional species in flocks in the proportion of the recordings that contain calls (n = 58 flock studies, 145 species), and especially alarm calls (n = 111 species). We found that leaders tended to have a higher proportion of their vocalizations that were classified as calls than occasional species, and both leaders and following species had a significantly higher proportion of their calls rated as alarms compared to occasional species. Next, we investigated the acoustic characteristics of flock participants’ calls, hypothesizing that leaders would make more calls, and have less silence on the recordings. We also hypothesized that leaders’ calls would be simple acoustically, as contact calls tend to be, and thus similar to each other, as well as being detectable, in being low frequency and with high frequence bandwidth. The analysis (n = 45 species, 169 recordings) found that only one of these predictions was supported: leading species were less often silent than following or occasional species. Unexpectedly, leaders’ calls were less similar to each other than occasional species. The greater amount of information available and the greater variety of that information support the hypothesis that leadership in flocks is related to vocal communication. We highlight the use of sound archives to ask questions about behavioral and community ecology, while acknowledging some limitations of such studies.  相似文献   

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