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1.
We use mitochondrial and nuclear sequence data to show that three weakly electric mormyrid fish specimens collected at three widely separated localities in Gabon, Africa over a 13-year period represent an unrecognized lineage within the subfamily Mormyrinae and determine its phylogenetic position with respect to other taxa. We describe these three specimens as a new genus containing two new species. Cryptomyrus, new genus, is readily distinguished from all other mormyrid genera by a combination of features of squamation, morphometrics, and dental attributes. Cryptomyrus ogoouensis, new species, is differentiated from its single congener, Cryptomyrus ona, new species, by the possession of an anal-fin origin located well in advance of the dorsal fin, a narrow caudal peduncle and caudal-fin lobes nearly as long as the peduncle. In Cryptomyrus ona, the anal-fin origin is located only slightly in advance of the dorsal fin, the caudal peduncle is deep and the caudal-fin lobes considerably shorter than the peduncle. Continued discovery of new taxa within the “Lower Guinea Clade” of Mormyridae highlights the incompleteness of our knowledge of fish diversity in West-Central Africa. We present a revised key to the mormyrid genera of Lower Guinea.  相似文献   

2.
Molecular phylogenetic evidence indicates that the octocoral family Alcyoniidae is highly polyphyletic, with genera distributed across Octocorallia in more than 10 separate clades. Most alcyoniid taxa belong to the large and poorly resolved Holaxonia–Alcyoniina clade of octocorals, but members of at least four genera of Alcyoniidae fall outside of that group. As a first step towards revision of the family, we describe a new genus, Parasphaerasclera gen. n., and family, Parasphaerascleridae fam. n., of Alcyonacea to accommodate species of Eleutherobia Pütter, 1900 and Alcyonium Linnaeus, 1758 that have digitiform to digitate or lobate growth forms, completely lack sclerites in the polyps, and have radiates or spheroidal sclerites in the colony surface and interior. Parasphaerascleridae fam. n. constitutes a well-supported clade that is phylogenetically distinct from all other octocoral taxa. We also describe a new genus of Alcyoniidae, Sphaerasclera gen. n., for a species of Eleutherobia with a unique capitate growth form. Sphaerasclera gen. n. is a member of the Anthomastus–Corallium clade of octocorals, but is morphologically and genetically distinct from Anthomastus Verrill, 1878 and Paraminabea Williams & Alderslade, 1999, two similar but dimorphic genera of Alcyoniidae that are its sister taxa. In addition, we have re-assigned two species of Eleutherobia that have clavate to capitate growth forms, polyp sclerites arranged to form a collaret and points, and spindles in the colony interior to Alcyonium, a move that is supported by both morphological and molecular phylogenetic evidence.  相似文献   

3.
The oomycete genus Aquastella is described to accommodate two new species of parasites of rotifers observed in Brooktrout Lake, New York State, USA. Three rotifer species – Keratella taurocephala, Polyarthra vulgaris, and Ploesoma truncatum – were infected, and this is the first report of oomycete infection in these species. Aquastella attenuata was specific to K. taurocephala and Aquastella acicularis was specific to P. vulgaris and P. truncatum. The occurrence of infections correlated with peak host population densities and rotifers were infected in the upper layers of the water column. Sequencing of 18S rRNA and phylogenetic analysis of both species placed them within the order Saprolegniales, in a clade closely related to Aphanomyces. The Aquastella species were morphologically distinct from other rotifer parasites as the developing sporangia penetrated out through the host body following its death to produce unique tapered outgrowths. Aquastella attenuata produced long, narrow, tapering, finger-like outgrowths, whilst A. acicularis produced shorter, spike-like outgrowths. We hypothesize that the outgrowths serve to deter predation and slow descent in the water column. Spore cleavage was intrasporangial with spore release through exit tubes. Aquastella attenuata produced primary zoospores, whereas A. acicularis released spherical primary aplanospores, more typical of other genera in the Aphanomyces clade.  相似文献   

4.
Xiao-Bin Song  Li-Zhen Li 《ZooKeys》2014,(424):91-100
Three new species belonging to two genera of the aleocharine tribe Termitopaediini Seevers, viz., Dioxeuta rara Song & Li, sp. n., D. yunnanensis Song & Li, sp. n., and Termitopulex sinensis Song & Li, sp. n. from Baihualing Natural Reserve (Southwest China: Yunnan) are described and illustrated. This is the first record of Termitopulex Fauvel, 1899 from China.  相似文献   

5.
The Migadopini are a small tribe of Carabidae with 47 species that occur in South America, Australia, and New Zealand, in the sub-Antarctic areas. In South America, most of the genera inhabit areas related to sub-Antartic Nothofagus forest except two monogeneric genera, the Ecuadorian genus Aquilex Moret and the Pampean genus Rhytidognathus Chaudoir. These two genera are geographically isolated from the remaining five South American genera. New material of Rhytidognathus from the northeast of Buenos Aires province and from Entre Ríos province permits establishing that the previous records of Rhytidognathus ovalis (Dejean) for Argentina were erroneous and that it belongs to a new species. Based on external morphological characters and from male and female genitalia we describe Rhytidognathus platensis as a new species. In this contribution we provide illustrations, keys, habitat characteristics and some biogeographic considerations on the distribution of Rhytidognathus.  相似文献   

6.
We describe a new species of the bufonid toad genus Rhinella from transition montane forest of the buffer zones of the Yanachaga-Chemillén National Park and the Pui Pui Protected Forest (eastern slopes of Andes, Selva Central, Peru). The new species belongs to the Rhinella margaritifera species group (confirmed by mtDNA data) and differs from all its members by the absence of tympanic membrane and tympanic annulus. It is characterized by medium size (SVL 57.5–65.5 mm, n = 5), moderately developed cranial crests, absence of neural crest of vertebrae, absence of bone protrusion at angle of jaw, presence of lateral rows of enlarged tubercles, and absence of subgular vocal sac and vocal slits in males. In addition, based on the molecular phylogenetic analyses of selected Rhinella species we propose the monophylum containing R. chavin, R. festae, R. macrorhina, R. manu, R. nesiotes, R. rostrata, and R. yanachaga as a new species group under the name Rhinella festae species group.  相似文献   

7.
The East Mediterranean species of Orthomus Chaudoir, 1838 are revised. The type series of Feronia longula Reiche & Saulcy, 1855, F. berytensis Reiche & Saulcy, 1855, F. proelonga Reiche & Saulcy, 1855, Orthomus longior Chaudoir, 1873, O. sidonicus Chaudoir, 1873, and O. berytensis akbensis Mateu, 1955 were studied and lectotypes for the first four are designated. Also, the following nomenclatural acts are proposed: Feronia proelonga Reiche & Saulcy, 1855, syn. n. of Orthomus berytensis (Reiche & Saulcy, 1855); Feronia elongata Chaudoir, 1859, syn. n. of Orthomus berytensis (Reiche & Saulcy, 1855); Orthomus sidonicus Chaudoir, 1873, syn. n. of Orthomus longior Chaudoir, 1873; Orthomus velocissimus andalusiacus Mateu, 1957, syn. n. of Orthomus velocissimus akbensis Mateu, 1955, new assignment for Orthomus berytensis akbensis Mateu, 1955. As a result, three species of the genus inhabit the East Mediterranean biogeographical region: O. berytensis, O. longior, and O. longulus. A key to these three species is given. O. longior is recorded for Turkey and Syria for the first time. In addition, a new synonymy of two West Mediterranean taxa is proposed: O. szekessyi (Jedlička, 1956), syn. n. of O. balearicus (Piochard de la Brûlerie, 1868), and a new genus and a species are described: Parorthomus gen. n. socotranus sp. n. (type locality: Republic of Yemen, Socotra Archipelago, Socotra Island, Fimihin env., 530 m.a.s.l.). Illustrations of the species dealt with here are provided including external characters, habitus, mentum and submentum, and genitalia are provided.Nine genera of the “African Series” of subtribe Euchroina Chaudoir, 1874 are keyed for the first time. Checklists of the species of Orthomus and of the Old World euchroine genera are given.  相似文献   

8.

Background and aims

Despite a recent new classification, a stable phylogeny for the cycads has been elusive, particularly regarding resolution of Bowenia, Stangeria and Dioon. In this study, five single-copy nuclear genes (SCNGs) are applied to the phylogeny of the order Cycadales. The specific aim is to evaluate several gene tree–species tree reconciliation approaches for developing an accurate phylogeny of the order, to contrast them with concatenated parsimony analysis and to resolve the erstwhile problematic phylogenetic position of these three genera.

Methods

DNA sequences of five SCNGs were obtained for 20 cycad species representing all ten genera of Cycadales. These were analysed with parsimony, maximum likelihood (ML) and three Bayesian methods of gene tree–species tree reconciliation, using Cycas as the outgroup. A calibrated date estimation was developed with Bayesian methods, and biogeographic analysis was also conducted.

Key Results

Concatenated parsimony, ML and three species tree inference methods resolve exactly the same tree topology with high support at most nodes. Dioon and Bowenia are the first and second branches of Cycadales after Cycas, respectively, followed by an encephalartoid clade (MacrozamiaLepidozamiaEncephalartos), which is sister to a zamioid clade, of which Ceratozamia is the first branch, and in which Stangeria is sister to Microcycas and Zamia.

Conclusions

A single, well-supported phylogenetic hypothesis of the generic relationships of the Cycadales is presented. However, massive extinction events inferred from the fossil record that eliminated broader ancestral distributions within Zamiaceae compromise accurate optimization of ancestral biogeographical areas for that hypothesis. While major lineages of Cycadales are ancient, crown ages of all modern genera are no older than 12 million years, supporting a recent hypothesis of mostly Miocene radiations. This phylogeny can contribute to an accurate infrafamilial classification of Zamiaceae.  相似文献   

9.
We describe a new species of Alopoglossus from the Pacific slopes of the Andes in northern Ecuador based on morphological and molecular evidence. The new species differs most significantly from all other congeners in having a double longitudinal row of widened gular scales, lanceolate dorsal scales in transverse rows, 29–32 dorsal scales in a transverse row at midbody, and 4 longitudinal rows of ventrals at midbody. It is most similar in morphology to A. festae, the only species of Alopoglossus currently recognized in western Ecuador. We analyze the phylogenetic relationships among species of Alopoglossus based on the mitochondrial gene ND4. Cis-Andean [east of the Andes] and Trans-Andean [west of the Andes] species are nested in two separate clades, suggesting that the uplift of these mountains had an important effect in the diversification of Alopoglossus. In addition, we present an updated key to the species of Alopoglossus.  相似文献   

10.
Ting-jing Li  Bin Chen 《ZooKeys》2014,(389):9-26
In this study, we recognize and review a total of 19 species of the genus Symmorphus Wesmael from China. We also provide a key to these species. Three new species are described and illustrated, namely Symmorphus (Symmorphus) tianchiensis Li & Chen, sp. n., S. (S.) cavatus Li & Chen, sp. n., and S. (S.) nigriclypeus Li & Chen, sp. n. The following four species are newly recorded from China: Symmorphus (S.) fuscipes (Herrich-Schaeffer), S. (S.) lucens (Kostylev), S. (S.) sublaevis Kostylev, and S. (S.) violaceipennis Giordani Soika. In addition, we map the species geographical distributions in China of these 19 species. Type specimens of these three new species are deposited in Chongqing Normal University and Yunnan Agricultural University.  相似文献   

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13.
A new genus and species of sea pen or virgulariid pennatulacean from the Gulf of Guinea in the tropical eastern Atlantic is described, and a key to the genera of the Virgulariidae is included. The new genus and species described here adds to the previously described five other genera of the family. It is distinguished by unique sclerite and polyp leaf characters from the superficially-similar genus Virgularia, which lacks conspicuous sclerites in the polyp leaves and coenenchyme (other than minute oval bodies that are generally <0.01 mm in length).  相似文献   

14.
New data on the Pselaphodes complex of genera (Pselaphitae: Tyrini) from China is presented. The generic limits of Labomimus Sharp and Pselaphodes Westwood are discussed and expanded. A revised key to the genera of the Pselaphodes complex is provided. New geographic evidence suggests that previously believed wide-spread species Pselaphodes tianmuensis Yin, Li & Zhao contains a number of related species, resulting in a division of the species to nine separate taxa. Fourteen new species belonging to three genera are diagnosed, described and illustrated: Dayao emeiensis Yin & Li, sp. n. (Sichuan), Labomimus fimbriatus Yin & Hlaváč, sp. n. (Yunnan), Labomimus jizuensis Yin & Hlaváč, sp. n. (Yunnan), Labomimus simplicipalpus Yin & Hlaváč, sp. n. (Sichuan), Pselaphodes anhuianus Yin & Li, sp. n. (Anhui), Pselaphodes daii Yin & Hlaváč, sp. n. (Sichuan), Pselaphodes grebennikovi Yin & Hlaváč, sp. n. (Yunnan), Pselaphodes hainanensis Yin & Li, sp. n. (Hainan), Pselaphodes kuankuoshuiensis Yin & Li, sp. n. (Guizhou), Pselaphodes longilobus Yin & Hlaváč, sp. n. (Hunbei, Yunnan), Pselaphodes monoceros Yin & Hlaváč, sp. n. (Xizang), Pselaphodes pengi Yin & Li, sp. n. (Sichuan), Pselaphodes tiantongensis Yin & Li, sp. n. (Zhejiang) and Pselaphodes wrasei Yin & Li, sp. n. (Yunnan). Labomimus sichuanicus Hlaváč, Nomura & Zhou (Sichuan) is redescribed and illustrated based on a paratype and the material from the type locality. Two recently described species, Pselaphodes tibialis Yin & Li (Yunnan), and Pselaphodes venustus Yin & Li (Yunnan), are transferred to Labomimus (comb. n.) due to the presence of a median metaventral fovea. New locality data is provided for Pselaphodes aculeus Yin, Li & Zhao (Anhui, Fujian, Guangxi, Hainan, Yunnan), Pselaphodes maoershanus Yin & Li (Guangxi, Guizhou), Pselaphodes tianmuensis (Zhejiang, Anhui, Fujian, Jiangxi, Guangxi) and Pselaphodes pectinatus Yin, Li & Zhao (Hainan), with the aedeagus newly illustrated for the latter species.  相似文献   

15.
The relative contributions of climate versus interspecific interactions in shaping species distributions have important implications for closely related species at contact zones. When hybridization occurs within a contact zone, these factors regulate hybrid zone location and movement. While a hybrid zone''s position may depend on both climate and interactions between the hybridizing species, little is known about how these factors interact to affect hybrid zone dynamics. Here, we utilize SDM (species distribution modeling) both to characterize the factors affecting the current location of a moving North American avian hybrid zone and to predict potential direct and indirect effects of climate change on future distributions. We focus on two passerine species that hybridize where their ranges meet, the Black‐capped (Poecile atricapillus) and Carolina (P. carolinensis) chickadee. Our contemporary climate models predict the occurrence of climatically suitable habitat extending beyond the hybrid zone for P. atricapillus only, suggesting that interspecific interactions primarily regulate this range boundary in P. atricapillus, while climatic factors regulate P. carolinensis. Year 2050 climate models predict a drastic northward shift in suitable habitat for P. carolinensis. Because of the greater importance of interspecific interactions for regulating the southern range limit of P. atricapillus, these climate‐mediated shifts in the distribution of P. carolinensis may indirectly lead to a range retraction in P. atricapillus. Together, our results highlight the ways climate change can both directly and indirectly affect species distributions and hybrid zone location. In addition, our study lends support to the longstanding hypothesis that abiotic factors regulate species'' poleward range limits, while biotic factors shape equatorial range limits.  相似文献   

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18.
Two North American species of green lacewings have undergone a number of changes in their generic assignments and are currently classified as incertae sedis. Here we demonstrate that adults (both sexes) and larvae of these species share a set of features that distinguishes them from currently described genera. Thus, to promote nomenclatural stability in Chrysopidae, we describe Kymachrysa, a gen. n. that contains the two species – Kymachrysa intacta (Navás), comb. n. and Kymachrysa placita (Banks), comb. n.. Also, we present modifications for the current generic-level key, illustrations, as well as biological information for identifying the genus and its known species.  相似文献   

19.
Michel Sartori 《ZooKeys》2014,(429):47-61
Based on historic collections and new material from Sumatra and Java, the species Rhithrogeniella ornata Ulmer, 1939, type species of the genus Rhithrogeniella, is reinvestigated. The nymph is described for the first time and is closely related to the continental Southeast Asian species Rhithrogeniella tonkinensis Soldán and Braasch, 1986. Rhithrogeniella belongs to the subfamily Ecdyonurinae, and is related to the genera Nixe Flowers, 1980 and/or Paracinygmula Bajkova, 1975 based on characters of the nymphal stage. Species described from Taiwan in the genus Nixe are transferred to the genus Rhithrogeniella: Rh. littoralis (Kang and Yang, 1994) comb. n., Rh. mitifica (Kang and Yang, 1994) comb. n. and Rh. obscura (Kang and Yang, 1994) comb. n.  相似文献   

20.
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