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1.

The Crenicichla mandelburgeri species complex from the Middle Paraná shows parallel evolution of ecomorphs to the unrelated C. missioneira species complex from the Uruguay River. In this article, we describe a new species from the C. mandelburgeri species complex that has evolved a parallel morphology and ecology to an unrelated species from the C. missioneira species complex (C. celidochilus). The new species is a pelagic predator that feeds predominantly on fishes and together with C. celidochilus is the only known pelagic species in the large riverine genus Crenicichla. The new species is endemic solely to a small tributary (the Urugua-í) of the Middle Paraná River where it is sympatric and partly syntopic with two other closely related endemic species that, however, differ strongly in their ecomorphologies (one is a generalistic invertivore and the other a specialized molluscivore). Mitochondrial DNA phylogeny finds the new species nested within the widespread C. mandelburgeri. Reduced genome-representation ddRAD analyses, however, demonstrate that this new species is of a hybrid origin and shares ancestry with C. ypo, one of the two studied sympatric species.

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2.
Host specialization is an important ecological characteristic of parasitic species. The identification of the parasitic strategy of the genus Stylops (Strepsiptera; Stylopidae) is, however, ambiguous. According to the number of recognized species based on existing taxonomy, highly specialized and supergeneralistic species exist in this genus. Our research aims to clarify the concept of host specialization in the genus Stylops, in which all of the members are parasites of Andrena bees. Based on the phylogenetic analysis of the parasites (mostly females) and the mapping of hosts onto the phylogenetic tree, we tested three hypotheses of host specialization: (1) each species of the genus Stylops is associated with a single host species; (2) Stylops species are specialized to a group of closely related hosts; and (3) a single Stylops species is a generalist, parasitizing all host Andrena species in this particular region. Our evidence clearly shows a close relationship between the parasite and the host: one species of Stylops attacks one or a few host species of Andrena bees, usually from a single subgenus. Moreover, a moderate generalistic strategy is also likely in a few Stylops species. According to our results, the species diversity of the strepsipteran parasites of bees must be reconsidered. A single European species of Stylops should be divided into a higher number of valid species. © 2015 The Linnean Society of London  相似文献   

3.
Puccinia lagenophorae is a rust fungus originating from Australasia which has spread throughout the world. A phylogenetic analysis of taxa related to this species was performed using rDNA (LSU, ITS) sequence data. The analyses revealed a well-supported cluster including all specimens of P. lagenophorae. By evaluating morphological and sequence data, the species is taxonomically re-defined and a list of synonyms is provided. Puccinia distincta on Bellis perennis, a species recently separated from P. lagenophorae, P. saccardoi, a species on the Goodeniaceae, and P. byliana, a species so far only known from South Africa, are reduced to synonymy in P. lagenophorae, as are several other species. Our analysis indicates that P. lagenophorae is likely not derived from the northern hemisphere species P. obscura, but from a species from Australia host-alternating between Asteraceae (aecial host) and Cyperaceae/Juncaceae (telial host). Another related species, P. stylidii (on Stylidium sp., Stylidiaceae) may have been derived from the same parental species as P. lagenophorae. From ontogenetical and morphological studies, the presence of pycnia could not be confirmed in the life cycle of this species, and the width of the pedicel of teliospores at the point of attachment was found to be highly variable and not a taxonomic character. The number of known host species is approximately 150, including 41 new host plants recorded herein.  相似文献   

4.

The genus Ctenomys includes a high number of taxa, with at least ten species from Patagonia and three recently described species for northeastern Chubut Province (Argentina). Ctenomys sociabilis is a social species of the genus Ctenomys and is currently distributed in the surrounding area of Sierra Cuyin Manzano (Neuquén Province), with a recently extinct population that occurred in Laguna Nahuelquir (Cushamen, Chubut Province). Molecular analyses have placed C. sociabilis at the base of Ctenomys clade, as the sister species to all other Ctenomys. Based on a morphological assessment (qualitative and quantitative) and DNA sequencing, we describe a new species of Ctenomys from Esquel, Chubut Province. Phylogenetic analysis shows the new species to be closely related to C. sociabilis, with evidence of solitary behavior. This new species is the first reported to be closely related phylogenetically to Ctenomys sociabilis at the base of the Ctenomys phylogeny. We provide anatomical comparisons between the new species and other species of Ctenomys from Patagonia, especially C. sociabilis.

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5.
Hou CL  Piepenbring M 《Mycopathologia》2005,159(2):299-306
Three species of Rhytisma are described based on recently collected specimens from the Anhui province, China. Rhytisma anhuiense is a new species causing a serious tar spot disease on Rhododendron simsii. Rhytisma yuexiense is a new species, which develops its stromata only on fallen leaves of Rhododendron ovatum. Rhytisma himalense on Ilex fargesii is a known species and probably widely distributed in China. Including the two new species, 11 species of Rhytisma are known from China which are presented in a key.  相似文献   

6.
The yucca moths (Tegeticula and Parategeticula) are of great importance in studies of coevolution because of their obligate mutualism with their yucca hosts. Historically, three species of Tegeticula have been recognized. One of them, T. yuccasella, has been regarded as the pollinator of all but two yucca species, but morphological, molecular and biological data show that this is a large complex of monophagous and oligophagous species that differ greatly in their biology. It also includes derived ‘cheater’ species that do not pollinate their hosts and oviposit into fruits rather than flowers. Here the yuccasella complex north of Mexico is revised. The nominotypic pollinator species yuccasella is redescribed, and ten new pollinator species described: altiplanella, baccatella, carnerosanella, cassandra, elatella, maderae, mojavella, rostratella, superficiella and treculeanella. Two non-pollinating cheater species are recognized. One such species originally misidentified as a Prodoxus species, then synonymised with yuccasella, is re-erected as the non-pollinating intermedia. In addition, the new non-pollinator species corruptrix is described.  相似文献   

7.
The genus Caryophyllia Lamarck, 1816 is the most diverse genus within the azooxanthellate Scleractinia comprising 66 Recent species and a purported 195 nominal fossil species. Examination of part of the deep-sea scleractinian collection made by the Paris Museum off New Caledonia and part of the material collected by CSIRO off Australian waters revealed the occurrence of 23 species of Caryophyllia, of which six are new to science. All new records, including the new species, are described, and synonyms, distribution, type locality, type material and illustration are provided for each species. An identification key to all Recent species of Caryophyllia is presented. In addition, the validity of the genus Caryophyllia was investigated by phylogenetic analyses of a dataset consisting of partial mitochondrial 16S rRNA sequences from 12 species assigned to this genus together with seven species representing some of the most morphologically similar caryophylliid genera, and 14 non-caryophyllid species representing 14 scleractinian families. Irrespective of the method of analysis employed, all of the Caryophyllia species formed a well-supported clade together with Dasmosmilia lymani and Crispatotrochus rugosus. Although based on a subset of the Recent Caryophyllia species, these results are consistent with Caryophyllia being a valid genus, but call for a reexamination of Dasmosmilia and Crispatotrochus.  相似文献   

8.
对近来记述的古北区东部地区的毛地蜂属Panurginus Nylander全部14个种作了补充研究。中国对该属的研究较少,仅知2种:黑足毛地蜂Panurginus nigripes Morawitz 和黄跗毛地蜂Panurginus flavotarsus ? Wu。黑毛地蜂Panurginus niger Nylander为该属的模式种,分布于俄罗斯和蒙古,本文报道该种为中国新记录种。目前,中国已知该属3种,分属于2个组即niger-group和herzi-group。文中提供了中国已知种类检索表。  相似文献   

9.
Trachinocephalus, a formerly monotypic and nearly circumtropical genus of lizardfishes, is split into three valid species. Trachinocephalus gauguini n. sp. is described from the Marquesas Islands and is distinguished from the two other species in the genus by having a shorter snout, a narrower interorbital space, larger eye and modally fewer anal‐fin and pectoral‐fin rays. The distribution of Trachinocephalus myops (type species) is restricted to the Atlantic Ocean and the name Trachinocephalus trachinus is resurrected for populations from the Indo‐West Pacific Ocean. Principal component analyses and bivariate plots based on the morphometric data differentiated T. gauguini from the other two species, but a substantial overlap between T. myops and T. trachinus exists. Phylogenetic evidence based on mtDNA COI sequences unambiguously supports the recognition of at least three species in Trachinocephalus, revealing deep divergences between the Atlantic Ocean, Indo‐West Pacific Ocean and Marquesas entities. Additional analyses of species delimitations using the generalized mixed Yule coalescent model and the Poisson tree processes model provide a more liberal assessment of species in Trachinocephalus, indicating that many more cryptic species may exist. Finally, a taxonomic key to identify the three species recognized here is provided.  相似文献   

10.
To understand the mechanisms driving species diversity is central to community ecology. Here, we explored if habitat partitioning is associated with a species‐rich ectoparasite community in small rodents from a tropical dry forest in western Mexico. We trapped 199 mice in three 0.5 ha‐plots from eight small rodent species for every two months, from July 2011 to April 2012, and collected their ectoparasites. We identified 17 species of mites, two sucking lice species, two phoretic species, and one commensal species. The most abundant ectoparasite species was Steptolaelaps liomydis, representing 42 percent of all ectoparasites collected; seven ectoparasite species had < 10 individuals. Eighteen ectoparasite species (of 22 species) were collected from the most abundant rodent Liomys pictus. C‐score and the number of checkerboard species pairs were significantly higher against a random expectation. Ectoparasite species in L. pictus mice showed host microhabitat partitioning; Fahrenholzia ehrlichi and Fahrenholzia texana were found only in the anterior dorsal area, Ornithonysus sp. occurred along the dorsal part, Ixodes species were restricted to the ears, and Steptolaelaps liomydis was found throughout the body. We also identified ectoparasite communities with distinct species composition in two rodent species that use contrasting macrohabitats (L. pictus, strictly terrestrial; Peromyscus perfulvus, mostly arboreal). The remaining and low abundant rodent species showed a species‐poor ectoparasite community composition. We conclude that habitat partitioning at both macro and microhabitat scales appeared to characterize the species‐rich ectoparasite community. Conversely, most rodent host species with low abundances showed a species‐poor ectoparasite community.  相似文献   

11.
Species ofAnthostomella reported from Brunei have been re-examined and the data is summarized in this paper. Five species are accepted, four are synonyms of previously described species and one is a new species. The new speciesAnthostomella oblongata is described and illustrated and a list ofAnthostomella species known from Brunei and a key to these species are provided.  相似文献   

12.
A new freshwater epiphytic Prorocentrum species, Prorocentrum rivalis, from the temperate region of the Haute-Vienne, France, is described. This species is the third freshwater species identified among approximately 60 marine Prorocentrum species. This new species is described using scanning electron microscope and phylogenetic analyses by a polyphasic approach (LSU rRNA sequences combined with 9 morphological characters). The phylogenetic analysis attests that P. rivalis is close to other planktonic freshwater species and the freshwater Prorocentrum clade is evolutionarily derived from an epiphytic freshwater prorocentroid ancestor. The unique marine species in the freshwater clade results from an ecophysiological reversion. P. rivalis differs from other epiphytic taxa by its rarity, its temperate distribution and its ecophysiological needs. The phylogeny confirms also that all planktonic Prorocentrum species are evolutionarily derived from epiphytic/benthic ancestors.  相似文献   

13.
14.
An updated, corrected checklist of both native and established alien freshwater fish species in Italy is given based on molecular, morphological and biogeographical data. Some 12 native species, reported as conspecific with transalpine species in official Italian ichthylogical literature, are in fact endemics. Previous taxonomic confusion has resulted in the introduction of several alien species, either with official stockings or mixed in as impurities. Rehabilitated species include the cyprinids Scardinius hesperidicus, Scardinius scardafa and Telestes savigny from northern Italy, as well as Squalius ruffoi and the Telestes comes from southern Italy. Squalius albus is a junior synonym of S. squalus. The endemic gudgeon, previously assigned to the genus Romanogobio, is returned to the genus Gobio (G. benacensis). Phoxinus lumaireul is a junior synonym of P. phoxinus. Among the Salmonidae, Salmo cenerinus is a junior synonym of S. marmoratus, while Salmo farioides represents the trout species of the Adriatic lineage for which a neotype is designated. Thymallus aeliani represents the endemic lineage of grayling of the Adriatic populations. The esocid Esox cisalpinus is an endemic pike species and Esox flaviae is a junior synonym; the extensive exportation as well as the presence of this species throughout Europe is possibly due to humans. Among sculpins, Cottus scaturigo and C. ferrugineus are junior synonyms of C. gobio. The International Union for Conservation of Nature (IUCN) categories for native species of Italy are updated. At present, 52 native freshwater fish species are listed: 2 are extinct (Acipenser sturio and Huso huso), 12 are critically endangered, 7 endangered, 10 vulnerable, 3 near‐threatened, 15 low concern and 3 data‐deficient; 35 species are the result of human transfers. Among the 51 introduced species, 6 are recently established (Leuciscus leuciscus, Oreochromis niloticus, Poecilia reticulata, Xiphophorus helleri, Amatitlania nigrofasciatus, Hemichromis sp.), 37 are already established, 5 are probably established and 3 are non‐established Chinese carp, maintained in the wild by intensive stockings. The family most involved is the Cyprinidae, with 22 alien and 20 native species.  相似文献   

15.
Among four different genera in Galaxauraceae, species diversity of the genus Tricleocarpa Huisman & Borowitzka is underestimated and requires further examination. In this study, we explored a molecular phylogeny of Tricleocarpa with an emphasis on Taiwan species and reassessed species diversity of the genus from the Indo-Pacific region based on analyses of rbcL and COI-5P sequences and morphological observations. The molecular analyses showed that species of Tricleocarpa examined are grouped into seven clades: six clades in the T. cylindrica group (the T. cylindrica complex, T. confertus, T. jejuensis, T. natalensis and two uncharacterized T. ‘cylindrica’ clades) and one clade as the T. fragilis group. Overall, at least 12 species in Tricleocarpa were detected from the Indo-Pacific region, including a new species, T. confertus S.-L. Liu & S.-M. Lin, from Taiwan. Among them, T. confertus can be separated from other species of Tricleocarpa by a thallus consisting of dichotomous or trichotomous, articulated and moniliform branches with smooth surfaces, constrictions at nodes and slightly anti-triangular in shape. The cystocarp morphology of T. confertus is similar to the T. cylindrica group by having paraphyses intermixing with gonimoblast filaments. Recognition of this new species from other species is also supported by the DNA-based, algorithmic species delimitation approaches. With the combination of molecular phylogeny and species diversity reassessment, our phylogeographic analysis supported a trend that species in the T. fragilis group are restricted in their distribution to subtropical and tropical areas whereas species in the T. cylindrica group have a wide distribution, ranging from temperate through to tropical areas.  相似文献   

16.
The beetle Osmoderma eremita has received much attention in the last few years, as it is among those species with the highest priority in the European Union's Habitat Directive. In this paper the species is evaluated as a potential indicator and umbrella species for the endangered beetle fauna in tree hollows. To be useful as an indicator of a species-rich fauna it should be easy to inventory and be strongly correlated with the presence of other species. An umbrella species is a species which is so demanding that the protection of this species will automatically save many others. The species richness of saproxylic beetles and occupancy of O. eremita were surveyed in tree hollows in an area in southeastern Sweden by assessing the presence/absence of living and dead adults (including fragments) and larvae. The species richness was higher when O. eremita was present, both at tree and stand level. Several threatened species were associated with the presence of O. eremita, whereas others did not correlate with the occurrence of O. eremita. As O. eremita is easy to find and identify, it is useful as an indicator of stands with a rich beetle fauna in tree hollows. Osmoderma eremita can be used as an umbrella species, because if measures are taken to conserve O. eremita, many other species in the same habitat are also conserved. However, there are some beetles in tree hollows which seem to be more sensitive to habitat fragmentation than O. eremita, and may go extinct if only O. eremita is taken into consideration.  相似文献   

17.
The Dimorphandra group, as traditionally circumscribed, is a rather diverse assemblage of genera in Leguminosae subfamily Caesalpinioideae that share certain morphological characteristics with the basally branching lineages of subfamily Mimosoideae. It currently comprises 51 species in seven genera: Burkea (1 species), Dimorphandra (26 species), Erythrophleum (10 species), Mora (6 species), Pachyelasma (1 species), Stachyothyrsus (2 species) and Sympetalandra (5 species). This study investigates the pollen morphology of 25 samples from 19 species of all seven genera. Pollen of the Dimorphandra group is small, isopolar, trizonocolporate and released in monads. Apertures are almost equal to polar length, with correspondingly small apocolpial areas. The shape of the aperture apices varies from acute to wide and rounded. Surface ornamentation is psilate, perforate, microreticulate, or perforate‐rugulate. The wall structure is usually columellate with a well developed foot layer. The pollen is small and unspecialised, agreeing with a previously noted pattern of more fixed and homogenous pollen structure in the more derived clades in subfamily Caesalpinioideae, compared with the great diversity of pollen types found in the basally branching lineages.  相似文献   

18.
Non-native tree species have been widely planted or have become naturalized in most forested landscapes. It is not clear if native trees species collectively differ in ectomycorrhizal fungal (EMF) diversity and communities from that of non-native tree species. Alternatively, EMF species community similarity may be more determined by host plant phylogeny than by whether the plant is native or non-native. We examined these unknowns by comparing two genera, native and non-native Quercus robur and Quercus rubra and native and non-native Pinus sylvestris and Pinus nigra in a 35-year-old common garden in Poland. Using molecular and morphological approaches, we identified EMF species from ectomycorrhizal root tips and sporocarps collected in the monoculture tree plots. A total of 69 EMF species were found, with 38 species collected only as sporocarps, 18 only as ectomycorrhizas, and 13 both as ectomycorrhizas and sporocarps. The EMF species observed were all native and commonly associated with a Holarctic range in distribution. We found that native Q. robur had ca. 120% higher total EMF species richness than the non-native Q. rubra, while native P. sylvestris had ca. 25% lower total EMF species richness than non-native P. nigra. Thus, across genera, there was no evidence that native species have higher EMF species diversity than exotic species. In addition, we found a higher similarity in EMF communities between the two Pinus species than between the two Quercus species. These results support the naturalization of non-native trees by means of mutualistic associations with cosmopolitan and novel fungi.  相似文献   

19.
A new species from Java, Hoya amicabilis S.Rahayu & Rodda is described and illustrated. It was first identified as a new species from pictures posted on social media in 2017. Hoya amicabilis is part of a small group of species that have an unusual shrubby habit, but it is the only one in that group with bright yellow campanulate flowers. Furthermore, Hoya amicabilis is a rather unusual species of Hoya since its staminal corona lobes are oblong, erect, while most species of Hoya have well‐developed generally spreading corona lobes, and its style head is umbonate, brightly coloured and extending above the anther appendages, while most species have a conical style head covered by anther appendages.  相似文献   

20.
ABSTRACT

Taxonomic information for New Zealand mosquito species is predominantly morphological with very few molecular data available to date. In this study, the mitochondrial COI gene and nuclear ITS1 were amplified and sequenced from DNA templates representing 17 species; 15 previously known New Zealand species, a newly discovered undescribed Aedes species from the Chatham Islands and a recently eradicated invader, Ae. camptorhynchus. This paper provides DNA barcoding sequences for the entire known New Zealand mosquito fauna, the first for the majority of these species. Phylogenetic analysis of COI and ITS1 indicated that the endemic species are all genetically distinct from the exotic species examined including vector species of pathogens of human diseases. The genus Opifex is distant from the genus Aedes based on analysis of ITS1 sequences, and Ae. chathamicus is more closely related to species within Aedes than to the genus Opifex. Results show Culex asteliae to be a valid species but Cx. rotoruae is not necessarily so. The Aedes species appears to be closely related to Ae. subalbirostris. The introduced Cx. quinquefasciatus was clearly shown to be related to Cx. pipiens; however, the endemic Cx. pervigilans was not. No evidence of population variation based on geographic location was detected.  相似文献   

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