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1.
《African Zoology》2013,48(2):298-308
The distribution of the scorpion genus Buthus Leach, 1815 includes southwestern Europe, North and Central Africa and extends east towards the Arabian Peninsula. Phylogenetic relationships within the genus are complex and remain partially unresolved despite several previous assessments. A set of three mitochondrial markers, 12s, 16s and CO1, revealed the presence of five well-supported clades: three clades endemic to Morocco, one clade distributed across the Maghreb region and southwestern Europe and one endemic to Tunisia and Algeria. Morocco presents high levels of endemism and appears to be the centre of diversity for the genus. Further differentiation was found within the clade distributed in Tunisia and Algeria, with the discovery of new phylogenetic patterns. In addition, a phylogeny combining all published CO1 data for the genus emphasized the ongoing complex situation regarding the genus’ taxonomy. Highly similar sequences were attributed to different species by different authors throughout the tree, and no differentiated monophyletic species could be resolved. This lack of congruence between morphologically defined species and genetic lineages is a major hindrance in the study of the highly complex genus Buthus.  相似文献   

2.
《African Zoology》2013,48(1):182-186
The Lufubu River is the largest tributary to the southern Lake Tanganyika and its upper reaches are eparated from the lake by rapids that prevent upstream movement of lacustrine fish. Thus, the ichthyofauna of the upper Lufubu River is clearly distinct from Lake Tanganyika and shows more similarities to the upper Congo and Zambezi systems. The phylogenetic relationships of three haplochromine cichlid species from the upper Lufubu River were analysed in the context of the phylogeographic structure of haplochromine cichlids from the surrounding hydrological systems. Patterns of genetic distances between the Lufubu fish and their sister taxa from the upper Congo system indicate that the headwaters of the Lufubu River were colonized from drainages pertaining to the Upper Congo system during extreme flooding or river capture events (at least several 100 000 years ago), possibly even three times independently. This study exemplifies how phylogeographic data from an understudied region might help to unravel unrecognized historical connections between separate water odies and drainage systems in a geologically/hydrologically unstable region.  相似文献   

3.
Two recent studies have suggested that divergent mitochondrial lineages may be present within spirostreptid genera such as Bicoxidens Attems, 1928. Bicoxidens, similar to many other endemic soil invertebrates, exhibits low dispersal capabilities and strict microclimate habitat preferences, attributes that often lead to geographic isolation. Given that prolonged geographic isolation often lays the foundation for population genetic differentiation, genetic divergence and possibly speciation, there was good reason to suspect that Bicoxidens may consist of several distinct lineages. On this basis, the mitochondrial cytochrome c oxidase subunit 1 (COI) was used to reconstruct the phylogeny of Bicoxidens and reveal divergent lineages within the genus. Maximum likelihood and Bayesian inference analyses recovered a paraphyletic Bicoxidens phylogram with divergent lineages present in three species – B. friendi, B. flavicollis and B. brincki – suggesting high genetic diversity within the genus. Bayesian genetic cluster analyses suggested the presence of multiple distinct mitochondrial lineages within the genus with four identified in B. flavicollis alone. It was therefore concluded that the divergent lineages observed among Bicoxidens populations may suggest the presence of hidden species.  相似文献   

4.
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5.
The phylogeny of European crayfish fauna, especially with respect to Eastern European species, is still far from being completely resolved. To fill this gap, we analyzed most of the European crayfish species focusing on the phylogenetic position of the endemic crayfish Astacus colchicus, inhabiting Georgia. Three mitochondrial and one nuclear marker were used to study evolutionary relationships among European crayfish species, resulting in the unique phylogenetic position of A. colchicus indicating independent species status to A. astacus. Phylogenetic analyses revealed a deep molecular divergence of A. colchicus in comparison to A. astacus (6.5–10.9% in mtDNA and 1.1% in nDNA) as well as to Pontastacus leptodactylus and P. pachypus (5.5–10.0% in mtDNA and 1.4–2.4% in nDNA). Absent ventral process on second male pleopod and abdominal somites II and III with pleura rounded lacking prominent spines clearly indicate taxonomic assignment to the genus Astacus; however, the species is distributed almost in the middle of Ponto-Caspian area typical by occurrence of the genus Pontastacus. Several morphological indices linked to head length, carapace, and total body length and width were found to demonstrate apparent differences between A. colchicus and A. astacus. Although this study provides a novel insight into European crayfish phylogeography, we also point out the gaps in comprehensive study of the P. leptodactylus species complex, which could reveal details about the potential species status of particular species and subspecies within this genus.  相似文献   

6.
The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders.  相似文献   

7.
《African Zoology》2013,48(2):315-320
Bulinus nyassanus, endemic to Lake Malawi, is an intermediate host for Schistosoma haematobium and plays an important role in transmission of this parasite along some shorelines on the Nankumba Peninsula in the southern part of the lake. Density of B. nyassanus in shallow water is usually low from January to April and a major population increase takes place during May to August when water temperatures are relatively low (about 22°C) and supposedly suboptimal for B. nyassanus. This study was designed to compare performance (growth, reproduction, survival, and hatchability of egg-masses) of B. nyassanus at four constant temperatures (22, 25, 28 and 31°C). Survival and reproduction were optimal at 25°C while growth and egg development were faster at the higher temperatures. Findings are discussed in view of the population dynamics of B. nyassanus at Cape Maclear.  相似文献   

8.
利用RAD-seq对中国桑属15个种进行了高通量测序,总共得到36.72Gb clean data,总Tags数2 788 927(reads),平均每个种原始数据都在10M以上,Tags都在20万条以上,质量值Q30都在90%以上。用Stacks软件对15个种进行比对,获得68904个SNPs位点。用最大似然法建树,分支图首先将白桑、广东桑分出,接着是山桑、鲁桑、瑞穗桑,再次分出的是鸡桑、细齿桑、蒙桑和鬼桑,最后分出的是黑桑、川桑、华桑、滇桑、长穗桑、奶桑。分支图能将栽培种和野生种完全分开;可以将蒙桑和鬼桑、鸡桑、华桑、川桑、奶桑分开。认为白桑、广东桑属原始类型,长穗桑、奶桑属进化类型;山桑、鲁桑、瑞穗桑这三个种被分在一个分支,自检支持率99%,黑桑、川桑这两个种被分在一个分支,自检支持率56%,长穗桑、奶桑这两个种被分在一个分支,自检支持率100%,说明这些种之间有较近的亲缘关系,桑属RAD-seq测序能大规模筛查SNPs位点,系统发育分析的准确性就更加可靠。  相似文献   

9.
《African Zoology》2013,48(3):83-97
Throughout the Miocene, the African landscape underwent broad climatic shifts that profoundly influenced the distribution of fauna and flora. Since the late Miocene, these shifts have created a landscape in southern Africa that is strongly characterised by savanna and arid environments. Forests persist in small fragments, primarily in mountainous or heterogeneous landscapes. Arthroleptis wahlbergii is a small frog endemic to eastern South Africa that has presumed low dispersal ability. Because of its preference for forests, the dynamics of forests since the late Miocene in this region might have promoted diversification within A. wahlbergii. To investigate whether habitat fragmentation might have driven divergences among populations, we carried out species distribution modelling and population level and phylogenetic analyses using two genetic loci (16S, mitochondrial; RAG-1, nuclear) sequenced for 48 individuals from 14 forests across the c. 500 km range of this species. There is substantial population-level structuring within A. wahlbergii, however the structure does not relate to forest types or catchments. We instead propose that the structure is a result of dynamic and idiosyncratic changes in forest connectivity over the Pleistocene. We identified two geographically circumscribed clades, the northern of which corresponds to true A. wahlbergii. The southern clade corresponds to populations from which Arthroleptis wageri FitzSimons, 1930 was described. This has long been considered a synonym of A. wahlbergii, but our molecular phylogenetic and distribution modelling supports recognising A. wageri as a distinct species.  相似文献   

10.
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11.
DNA barcoding has been proposed as a method for species identification. However, this method has been criticised for its over-reliance on a single mitochondrial gene. In this study, four mitochondrial gene regions and one nuclear gene region were used to investigate their different abilities to identify tissue associated with museum specimens of Aethomys chrysophilus, Aethomys ineptus and Micaelamys namaquensis. Aethomys chrysophilus and the more recently elevated A. ineptus are indistinguishable on morphological grounds; however, their ranges are largely parapatric with only one syntopic locality currently known. All of the mitochondrial gene regions were able to separate M. namaquensis from A. chrysophilus and A. ineptus, but they varied in their abilities to resolve differences between A. chrysophilus and A. ineptus. The sequence results identified a specimen from KwaZulu-Natal that was misclassified and should have been identified as A. ineptus. Seven specimens that had not been reclassified following the elevation of A. ineptus to species level were identified as A. ineptus. Individuals of A. chrysophilus from Malawi could not be classified as either A. chrysophilus or A. ineptus, and may be a hybrid or a new, distinct species. This study indicates that DNA barcoding may be used to separate M. namaquensis from A. chrysophilus and A. ineptus, and although it was not able to separate A. chrysophilus and A. ineptus, it did indicate specimens from Malawi may be a new cryptic species.  相似文献   

12.
The previously unknown life-cycles of Haemonchus bedfordi, Impalala tuberculata and Longistrongylus sabie parasitic in impala, are recorded. Observations on the morphology of the developmental stages and their habitat of these three nematode species are described. The similarities and differences to closely related species or subspecies are discussed.The morphology of the developmental stages of Haemonchus bedfordi are compared to the Haemonchus spp., H. contortus and H. placei.  相似文献   

13.
《African Zoology》2013,48(2):271-284
Phylogenetic relationships in the genus Aethomys were examined based on qualitative cranial data for all currently recognized species. A cladistic analysis suggested the presence of three clades: 1) A. bocagei, A. thomasi, A. silindensis, A. kaiseri, and A. nyikae;2) A. chrysophilus, A. ineptus, and A. hindei;3) A. granti, A. namaquensis, and A. stannarius. These phylogenetic groupings are largely inconsistent with previously postulated supraspecific relationships for the genus. Nonetheless, relationships within each clade broadly correspond with some previously suggested evolutionary hypotheses among some members of the genus, the only notable exception being a close affinity between two southern African taxa (A. namaquensis and A. granti) and the geographically disjunct West African endemic, A. stannarius. A phylogram derived from an analysis of anagenetic divergence among taxa supported the widely-held view of a close affinity between A. namaquensis and A. granti that has traditionally led to their inclusion in the subgenus Micaelamys. These results are relatively concordant with recent molecular studies based on microcomplement fixation of albumin, mitochondrial DNA cytochrome b and 16S rRNA data, which collectively suggest that the genus Aethomys is paraphyletic. Possible paraphyly is also reflected by a relatively low bootstrap value at the node uniting all ingroup taxa in this study, as well as previous studies on dental morphology, modes of karyotypic change, and gross sperm and bacular morphology, and strongly supports the taxo-nomic elevation of the currently recognized subgenera Micaelamys and Aethomys to full generic rank. Despite the broad correspondence between the morphological and molecular data, homoplasy and low bootstrap support in the present investigation point to the need for a careful consideration of the power and choice of morphological characters in future studies on this and related groups of murine rodents.  相似文献   

14.
A novel herpesvirus was found by molecular methods in samples of Lake Trout Salvelinus namaycush from Lake Erie, Pennsylvania, and Lake Ontario, Keuka Lake, and Lake Otsego, New York. Based on PCR amplification and partial sequencing of polymerase, terminase, and glycoprotein genes, a number of isolates were identified as a novel virus, which we have named Namaycush herpesvirus (NamHV) salmonid herpesvirus 5 (SalHV5). Phylogenetic analyses of three NamHV genes indicated strong clustering with other members of the genus Salmonivirus, placing these isolates into family Alloherpesviridae. The NamHV isolates were identical in the three partially sequenced genes; however, they varied from other salmonid herpesviruses in nucleotide sequence identity. In all three of the genes sequenced, NamHV shared the highest sequence identity with Atlantic Salmon papillomatosis virus (ASPV; SalHV4) isolated from Atlantic Salmon Salmo salar in northern Europe, including northwestern Russia. These results lead one to believe that NamHV and ASPV have a common ancestor that may have made a relatively recent host jump from Atlantic Salmon to Lake Trout or vice versa. Partial nucleotide sequence comparisons between NamHV and ASPV for the polymerase and glycoprotein genes differ by >5% and >10%, respectively. Additional nucleotide sequence comparisons between NamHV and epizootic epitheliotropic disease virus (EEDV/SalHV3) in the terminase, glycoprotein, and polymerase genes differ by >5%, >20%, and >10%, respectively. Thus, NamHV and EEDV may be occupying discrete ecological niches in Lake Trout. Even though NamHV shared the highest genetic identity with ASPV, each of these viruses has a separate host species, which also implies speciation. Additionally, NamHV has been detected over the last 4 years in four separate water bodies across two states, which suggests that NamHV is a distinct, naturally replicating lineage. This, in combination with a divergence in nucleotide sequence from EEDV, indicates that NamHV is a new species in the genus Salmonivirus.

Received April 20, 2015; accepted October 11, 2015  相似文献   


15.
Socially parasitic ants of the formicoxenine genus Myrmoxenus exhibit considerable diversity in colony structure and life history. While some species are active slave‐makers with many workers and others are workerless ‘murder‐parasites,’ Myrmoxenus kraussei is considered as a ‘degenerate slave‐maker’ because of its very low worker numbers. Here, we document that Temnothorax recedens host workers in single colonies of M. kraussei from Lago di Garda, Italy, exhibit significantly more genetic diversity than workers in unparasitized colonies. This raises the possibility that, despite its low worker numbers, M. kraussei may actively engage in slave raids in nature.  相似文献   

16.
《African Zoology》2013,48(1):8-15
The systematics of the genus Acanthodactylus was classically based on external morphological traits, osteological characters and morphology of the hemipenes. Although the identification of species complexes is relatively easy, the distinction within some groups is difficult due to a high variability of the external morphology. Partial mitochondrial (12S and 16S rRNA) sequences (371 and 499 base pairs, respectively) were analysed from 32 specimens of the A. pardalis group from northern Africa including the described species A. busacki, A. maculatus, A. mechriguensis and A. pardalis. Several highly distinct genetic units were resolved, but with little support for relationships between them. These units did not coincide with current taxonomic units, but showed geographic structuring. Although the A. pardalis group displays significant variation, the present taxonomy of the group must be considered unsatisfactory since it is not supported by genetic evidence. For some forms, such as A. mechriguensis there is no support and it is suggested that it should be synonymized with A. maculatus. More data are clearly needed for other forms. Complex microevolutionary patterns due to the recent contraction/ expansion phases of the Sahara Desert probably are related with the phylogenetic patterns observed.  相似文献   

17.
Mycobacteriosis due to mycobacteria is one of the most common bacterial diseases in ornamental fish. We describe here the phenotypic and genotypic characteristics of Mycobacterium isolates from fighting fish Betta spp. using ATCC Mycobacterium marinum, Mycobacterium fortuitum and Mycobacterium chelonae as references. A total of four isolates (M1, M2, M3, M4) were obtained from four out of 106 fish samples using selective agar, and identified to Mycobacterium genus using acid-fast staining and 16s rRNA gene-based genus specific polymerase chain reaction. DNA sequencing and NCBI-BLAST analysis further identified isolate M1 as M. marinum and isolates M2, M3, M4 as M. fortuitum. Morphological, physiological and biochemical tests were carried out for phenotypic characterizations. Universal M13 and wild-type phage M13 RAPD dendogram was generated to illustrate the genetic relationship of the isolates and reference strains.  相似文献   

18.
Fecal DNA analysis is a useful tool for the investigation of endangered species. Tamaraw (Bubalus mindorensis) is endemic to the Philippine island of Mindoro but knowledge of its genetic and ecological information is limited. In this study, we developed a species identification method for tamaraw by fecal DNA analysis. Eighteen feces presumed to be from tamaraw were collected in Mount Iglit‐Baco National Park and species‐known feces from domestic buffaloes and cattle were obtained from a farm. Additionally, one species‐unknown fecal sample was obtained in Mount Aruyan Preserve, where the sighting of tamaraw has not been reported in recent years. Based on DNA sequence data previously reported, the genus Bubalus‐ and tamaraw‐specific primers for PCR of cytochrome b gene were newly designed. The Bubalus‐specific primer yielded a 976 bp fragment of cytochrome b for all fecal samples from tamaraw and domestic buffaloes, but not for cattle, whereas the tamaraw‐specific primer yielded a 582 bp fragment for all tamaraw fecal samples and for one of the four domestic buffalo samples. PCR‐RFLP (restriction fragment length polymorphism) analysis of the 976 bp PCR fragment with AvrII or BsaXI provided distinct differences between tamaraw and domestic buffalo. PCR‐RFLP analysis also showed that the species‐unknown sample obtained in Mount Aruyan Preserve, originates from tamaraw.  相似文献   

19.
In this study, we present an assessment of the evolutionary history and phylogenetic relationships of Asian mountain voles of the subgenus Aschizomys, genus Alticola, based on extensive sampling and phylogenetic analyses of data from mitochondrial and nuclear markers. Two species of this subgenus are widespread in the mountain areas of north‐eastern Asia. However, both their distribution and taxonomic borders remained questionable for more than 100 years. Our study showed discordance in the phylogenetic patterns between nuclear and mtDNA markers. We found that mtDNA in A. lemminus is paraphyletic relative to A. macrotis, but nuclear markers demonstrated reciprocal monophyly. According to species distribution modeling, ranges of A. macrotis and A. lemminus experienced a secondary contact during the Last Glacial Maximum (approximately 22 kyr BP), and thus a hybridization event seems plausible during that period. Species tree analyses recovered a sister group relationship between the two species of the Aschizomys subgenus, with an estimated divergence date of around 0.8 Ma. Our results provided good support for currently recognized subspecies within both A. macrotis and A. lemminus based on mitochondrial and nuclear datasets. A new, yet undescribed form, supposedly of a subspecific status within A. lemminus, was found in the Bureinskiy Range in the Khabarovsk area. This finding expands the current species distribution range further to the southeast.  相似文献   

20.
Massive actions have been and are being taken into protecting the world's primates from extinction, while the study of the properties of genetic diversity, demographic history, and ecological relationships will benefit the understanding of the long-term survival of a species. The Taihangshan macaque (Macaca mulatta tcheliensis), a subspecies of rhesus macaque (Macaca mulatta), is endemic to China and currently restricted to southern Mt. Taihangshan area. Herein, we evaluated the genetic diversity, population structure, and demographic history of this subspecies using mitochondrial (Cytb and high variable region I: HVR I) and nuclear markers (microsatellite loci) of 131 individuals collected from 9 localities covering the distribution range of this subspecies. Both phylogenetic analyses and genetic assignment revealed that the wild populations of Taihangshan macaques could be divided into 2 major highly divergent clades, THS-east and THS-west. Low genetic diversity (π: 0.00266 ± 0.00016) but high haplotype diversity (Hd: 0.80352 ± 0.015) were detected in the Taihangshan macaques, particularly in THS-east. Analyses of demographic history suggested that the Taihangshan macaques experienced first a stable historical population size from Holocene to early 19th century but a subtle decline and then slight growth in the recent 200 years. We suggest that bridging the neighbor populations (i.e. setting corridors) would facilitate the male-mediated gene flow and subsequently increase the genetic diversity of the Taihangshan macaque populations.  相似文献   

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