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1.
This work stems from the results of a recent phylogenetic investigation on the Euscorpius carpathicus species complex from the Italian peninsula (Salomone et al. 2004. Phylogenetic relationships between the sibling species Euscorpius tergestinus and E. sicanus (Scorpiones, Euscorpiidae) as inferred from mitochondrial and nuclear sequence data. In: Proceedings of the16th Congress of Arachnology, August 2-7, 2004, Ghent University, Belgium, 268pp.; Salomone et al. in prep.). Molecular investigation produced interesting and unexpected findings on the scorpion Euscorpius tergestinus (C.L. Koch, 1837). Both nuclear and mitochondrial sequence data provided evidence of substantial genetic differentiation in specimens identified as Euscorpius tergestinus according to recent taxonomical changes (Fet and Soleglad 2002. Morphology analysis supports presence of more than one species in the “Euscorpius carpathicus” complex (Scorpiones: Euscorpiidae). Euscorpius 3, 51pp.). These specimens clearly belong to two well-differentiated evolutionary lineages. Molecular results highlighted the need for a new morphological investigation. The present study undertook the morphological analysis of specimens belonging to both genotypes with the aim of identifying morphological characteristics able to discriminate between the two taxa. The analysis of trichobothria patterns, morphometric ratios, granulation patterns and the observation of the pectinal sensilla confirm the difficulty in distinguishing these two genotypes and the high polymorphism of the subgenus Euscorpius Thorell, 1876. The length of pedipalp segments and dorsal patellar spurs (DPS), as well as femur leg granulation, are the main diagnostic characters; other ratios together with body color also help to distinguish the different genotypes. This study confirms the presence in Italy of two different cryptic species belonging to the “Euscorpius tergestinus” complex. Euscorpius tergestinus is a reddish, slender euscorpiid with a large dorsal patellar spine (DPS). A darker and generally squat phenotype with a short DPS, which corresponds to Euscorpius carpathicus concinnus sensu Caporiacco (1950), is elevated to the species level: Euscorpius concinnus (C.L. Koch, 1837). These two species are sympatric in several Italian regions, and their distribution pattern is possibly determined by intraguild predaction interaction.  相似文献   

2.
The scorpion of Montecristo Island (Tuscan Archipelago, Italy): Euscorpius carpathicus oglasae Di Caporiacco, 1950, is a poorly known taxon. We redescribe and illustrate the insular endemism of E. c. oglasae for the first time, and elevate this subspecies to the rank of species following a thorough study of the comparative morphology of 372 specimens (including 7 related taxa). Euscorpius oglasae stat. nov. is an oligotrichous form that differs from the related species by the inner proximal surface of pedipalp movable finger, with a reduced lobe and a slightly swollen telson vesicle in males. Attention was given to the analysis of the hemispermatophore and peg sensilla of pectens. The hemispermatophore is small, with the basal lobe bearing a very short spine. We also discuss aspects of the ecology, conservation and biogeography of this species.  相似文献   

3.
Phylogenetic analysis of the genus Euscorpius (Scorpiones: Euscorpiidae) across the Mediterranean region (86 specimens, 77 localities, four DNA markers: 16S rDNA, COI, COII, and ITS1), focusing on Greek fauna, revealed high variation, deep clade divergences, many cryptic lineages, paraphyly at subgenus level, and sympatry of several new and formerly known lineages. Numerous specimens from mainland and insular Greece, undoubtedly the least studied region of the genus' distribution, have been included. The reconstructed phylogeny covers representative taxa and populations across the entire genus of Euscorpius. The deepest clades detected within Euscorpius correspond (partially) to its current subgeneric division, outlining subgenera Tetratrichobothrius and Alpiscorpius. The rest of the genus falls into several clades, including subgenus Polytrichobothrius and a paraphyletic subgenus Euscorpius s.s. Several cryptic lineages are recovered, especially on the islands. The inadequacy of the morphological characters used in the taxonomy of the genus to delineate species is discussed. Finally, the time frame of differentiation of Euscorpius in the study region is estimated and the distributional patterns of the lineages are contrasted with those of other highly diversified invertebrate genera occurring in the study region. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 728–748.  相似文献   

4.
5.
A new species of the genus Euscorpius Thorell, 1876is described based on specimens collected from Dilek Peninsula (Davutlar, Aydın) in Turkey. It is characterized by an oligotrichous trichobothrial pattern (Pv= 7, et= 5/6, eb= 4) and small size. Euscorpius (Euscorpius) avcii sp. n. is the first named species of the subgenus Euscorpius from Turkey.  相似文献   

6.
A new species of the genus Euscorpius Thorell, 1876 is described based on specimens collected from Bursa Province, in Marmara Region of Turkey. It is characterized by a mesotrichous trichobothrial pattern (Pv= 8, et= 6, em=4, eb= 4), medium size and light coloration. Euscorpius (Euscorpius) rahsenae sp. n. is the second species of the subgenus Euscorpius recognizedin Turkey.  相似文献   

7.
Allozymes and morphological characters were used to test whether host race evolution—the genetic divergence of parasitic populations caused by adaptation to different host species—has occurred in desert mistletoe,Phoradendron californicum. Populations ofPhoradendron californicum from two hosts,Acacia greggii andProsopis glandulosa, were surveyed from the Mojave and Colorado deserts. Electrophoretic data indicated genetic differentiation of mistletoes occurring on these hosts. Three of four morphological characters (internode length, main shoot lateral shoot diameter ratio and berry color) also showed significant host-specific differentiation. These data support the hypothesis that host race formation has occurred or is occurring in this parasitic angiosperm.  相似文献   

8.
The taxonomic problem of the cyprinid species of genus Spinibarbus, occurring in southern China and northern Vietnam, was resolved on the basis of molecular and morphological analyses. Spinibarbus caldwelli and Spinibarbus hollandi have a smooth posterior edge of the last unbranched dorsal fin ray among species in the genus. Spinibarbus caldwelli is currently regarded as a junior synonym of S. hollandi because of ambiguities in diagnostic characters. In this article, 11 mtDNA cytochrome b sequences of Spinibarbus specimens were analyzed together with Barbodes gonionotus and Puntius conchonius as outgroups. Our results showed that specimens identified as S. hollandi from Taiwan were different from those from the Asian mainland at a high level of genetic divergence (0.097–0.112), which is higher than that between the two valid species, S. sinensis and S. yunnanensis (0.089), and suggested that Taiwan specimens should be considered as a different species from the Asian mainland one. In a molecular phylogenetic analysis, the sister-group relationship between Taiwan specimens and the Asian mainland specimens was supported strongly by a high confidence level (100% in bootstrap value). Further analysis of morphological characters showed that overlap of diagnostic characters is much weaker than previously suggested. Taiwan specimens had 8 branched rays in the dorsal fin, whereas those from the mainland had almost 9–10. The molecular and morphological differences suggest S. caldwelli to be valid. The molecular divergence shows the genetic speciation of S. hollandi and S. caldwelli might have occurred 5.6–4.9 million years ago; the former could be a relict species in Taiwan, and the latter dispersed in the Asian mainland.  相似文献   

9.
An experimental crossing program was carried out in order to test the hypothesis thatArmeria villosa subsp.carratracensis, a serpentine endemic from Southern Spain, is of hybrid origin. Fruit-set and mainly pollen stainability data in artificial hybrids demonstrate that internal interspecific barriers are weak. Two generations of backcrossing with the two putative parents —A. colorata andA. villosa subsp.longiaristata— can restore pollen stainability to an average of 83.2 and 68.7, respectively. A morphometric analysis of 148 specimens belonging to parental species, different artificial hybrid generations and wild putative hybrid race shows that (1) morphological characters have a strong genetic basis and thus are good markers in identifying hybrids and introgression inArmeria; (2) artificial backcrossing produces in morphometrical characters a variation which conforms in both trend and magnitude to what is commonly attributed in the wild to introgression; (3) the position of the putative hybrid race is intermediate between the two parental species used in the program. These results are in accordance with the hypothesis of hybrid origin ofA. villosa subsp.carratracensis. Natural and experimental hybridization inArmeria, I  相似文献   

10.
Body size and colouration are two characters commonly used in the taxonomy of many animal taxa. However, they are seldom used by earthworm taxonomists because they are subject to environmental influences and tend to vary intraspecifically. In the present study, DNA sequences of the mitochondrial COI gene are used to evaluate whether specimens of the megascolecid earthworm Amynthas wulinensis Tsai, Shen & Tsai, 2001 that differ in body size and/or colouration belong to different genetic lineages. Phylogenetic analyses and morphological comparisons indicate that A. wulinensis in the previous broad sense is a species complex composed of three species differing in body size, colouration, and genital markings. Consequently, two new species, Amynthas lini and Amynthas meishanensis, are described. Taxonomic affinities of the A. wulinensis species complex are discussed, as is the feasibility of using body size and colouration in earthworm taxonomy.  相似文献   

11.
The shape and the mode of dehiscence of the capsule had been regarded as good differential characters betweenAcanthophyllum and related genera.—Studies of these characters, including the shape of the ovary, in species ofAcanthophyllum, Diaphanoptera, Ochotonophila andScleranthopsis show, however, that they cannot be used as differential characters for the genusAcanthophyllum. Dedicated to Prof.K. H. Rechinger on the occasion of his 80th birthday.  相似文献   

12.
Echinochloa (Poaceae) includes two domesticated species,Echinochloa utilis (Japanese barnyard millet) andE. frumentacea (Indian sawa millet) and 20–30 wild species. The two millets are morphologically very variable and overlap in spikelet and inflorescence characteristics. Both species are hexaploids based on x = 9. Cytogenetic studies point to the hexaploid wild speciesE. crusgalli andE. colona as possible progenitors ofE. utilis andE. frumentacea, respectively. The tetraploidE. oryzoides is considered as a possible genome donor to wild and domesticated barnyard millet. Markers from Random Amplified Polymorphic DNA method were used to assess the proposed phylogeny and examine the genetic diversity in both domesticated and wild species. The data were analyzed numerically.Echinochloa utilis andE. frumentacea appear very distinct, but grouped withE. crusgalli andE. colona, respectively. The tetraploidE. oryzoides show strong genetic affinity to theE. utilis—E. crusgalli group. The data are in general agreement with the cytogenetic information; however, some disagreements on the interpretation of some of the cytogenetic information is raised. The variability in DNA markers observed in the domesticated species, particularlyE. frumentacea, points to the feasibility of using RAPD markers in cultivar fingerprinting and breeding programs of these millets.  相似文献   

13.
Pollination ofDianthus gratianopolitanus was studied in a population of the Swiss Jura mountains. Pollinators of this plant species are reported here for the first time. The flowers were not only visited by butterflies as postulated in the literature, but also by diurnal hawkmoths (Macroglossum stellatarum) and by diurnal and nocturnal noctuid moths. — Nectar is sucrose-dominant, the sugar concentration is moderate but the amino acid concentration is high. Nectar characteristics correspond well with the syndrome ofLepidoptera-pollinated flowers. — Field observations and flower characters (colour, range of the calyx length) suggest thatDianthus gratianopolitanus is an intermediate species in the transition of butterfly to moth pollination. — Lack of reproductive success inDianthus gratianopolitanus can not be attributed to lack of suitable pollinators.  相似文献   

14.
Using standard and multivariate statistic methods, an epigenetic character—foramina in fossa condyloidei inferior(FFCI)—was studied in sable populations. This character was shown to be most frequent in southeastern populations of the species (Primorye and the Baikal region) while its distribution in the remaining part of the range was polyclinal. The expression of FFCI was directly associated with coat color and longitude, and inversely associated with skull size. This trend was broken by some western populations formed in the 1950s by introduction, which exhibited stable morphological differences with adjacent aboriginal sable populations. Most populations of the species exhibit differences in the manifestation of the studied characters. Frequency of the FFCI manifestation can be used as an additional population characteristic, an associative diagnostic character that shows high discriminating capability in detecting phenogenetic relationships of intraspecific groups.  相似文献   

15.
Schoenus ferrugineus andS. nigricans have restricted distributions in Sweden and are almost exclusively confined to calcareous fen habitats. AtS. nigricans sites,S. ferrugineus is usually also present, and hybrids are frequently found. In this report, I used allozymes to estimate the amount of gene flow between the two species, and to compare the partitioning of genetic diversity in each of them. Thirteen loci were analysed at eight different enzyme systems. Seven loci were variable between or within the species. The two species had completely different alleles at two of the seven variable loci, whereas there was overlap at five loci. In all, 22 different alleles were found. Six of these alleles were confined toS. nigricans, and five alleles were confined toS. ferrugineus. Nei's genetic identity was 0.55.—InS. ferrugineus, three loci (23%) were polymorphic, and the average number of alleles per polymorphic locus was 2.0 (each polymorphic locus had two alleles). InS. nigricans, three loci (23%) were polymorphic, and the average number of alleles per polymorphic locus was 2.3.—The proportion of genetic diversity due to variation among sites (G ST) was fairly similar in the two species, mean over loci = 0.12 inS. ferrugineus and 0.15 inS. nigricans. However, the proportion of genetic diversity due to variation among individuals within sites (G IS) differed markedly between the two species, mean over loci = 0.54 inS. ferrugineus and 0.17 inS. nigricans. Accordingly, there was a much higher individual heterozygosity inS. nigricans than inS. ferrugineus. — Most hybrids were interpreted as F1 hybrids. However, a small proportion, 0.5–1.6 %, were Fn hybrids or back-crosses.—On the Swedish mainland, all former occurrences ofS. nigricans are extinct, but viable hybrids are still present at a few sites in southernmost Sweden.  相似文献   

16.
We used RAPDs (Random Amplified Polymorphic DNA) to test genetic divergence between two populations of Bosmina spp. in Lake Östersjön, Sweden. Previous taxonomic studies on European species within the genus Bosmina have been based on morphological characters alone. RAPD markers distinguished the two populations and supported the specific status of B. coregoni and B. longispina based on morphological characters. Furthermore, juveniles with a long antennule and a mucro were classified as B. coregoni. RAPDs also revealed genetic differences among the tested individuals, suggesting several clones within each species.  相似文献   

17.
Butterflies in the genera Heliconius and Laparus obtain fitness-related benefits from using amino acids derived from pollen. These butterflies have morphological features of the proboscis that facilitate pollen-feeding. Here we investigate behavioral characteristics potentially involved in pollen-gathering. Analysis of four behavioral characters showed that pollen-feeding species manipulate Lantana flowers faster and more thoroughly compared to non-pollen-feeding relatives. Although this suggests that pollen-feeding species are potentially more efficient in harvesting pollen, every butterfly tested successfully removed pollen from Lantana and non-pollen-feeding butterflies generally extracted larger amounts of pollen than Heliconius and Laparus. Morphological characteristics of the proboscis and the production of abundant fluid exudate help keep pollen attached in the proboscis for long periods of time—possibly key to Heliconius' and Laparus' ability to obtain amino acids from pollen. Our results, in concert with those of previous morphological analysis, indicate that behavioral and structural attributes associated with pollen-feeding in Heliconius and Laparus are subtle modifications of widespread butterfly characteristics and raise the question why other butterflies do not use pollen in their diet.  相似文献   

18.
Results obtained from crossing experiments betweenP. somniferum subsp.somniferum (2n = 22) and subsp.setigerum (2n = 44),P. glaucum (2n = 14) andP. gracile (2n = 14) and from the observation of meiotic chromosome pairing in the various hybrids obtained do not provide straightforward evidence for the hypothesis thatP. somniferum originated as a triploid hybrid between taxa similar toP. glaucum andP. gracile (Kadereit 1986a, b).—On the one hand, the pattern of crossability found reflects the closer similarity of subsp.somniferum toP. glaucum and of subsp.setigerum toP. gracile, which was interpreted as segregation of parental characters, and the high frequency of 2n = 28 chromosomes among F2-progeny from the hybrid subsp.somniferum × subsp.setigerum (2n = 33) might reveal n = 7 as the base number also ofP. somniferum. On the other hand, however, the general difficulty of obtaining hybrids, and the low incidence of bivalent formation in their meiosis, probably indicating a lack of chromosome homology between the different species, do not fit the above hypothesis.—These results are in marked contrast to the morphological similarity between the three species involved.  相似文献   

19.
Polyacrylamide gel electrophoretic study of 8 isoenzyme systems encoded by 16 putative gene loci in 23 species of American beans of the genusPhaseolus s. str. and in the Asian moth beanVigna aconitifolia revealed in total 98 allozymes, including 34 taxon-specific and unique, 14 rare-unique and 50 shared allozymes. —P. xanthotrichus var.xanthotrichus and var.zimapanensis differed in allozymes of AAT-A, AAT-D and ADH-C.P. xanthotrichus var.zimapanensis andP. hintonii shared same allozymes of AAT-A and AAT-D, but differed in allozymes of ADH-A and ADH-C. It is proposed to recognizeP. xanthotrichus var.zimapanensis in species rank asP. zimapanensis. — P. acutifolius var.acutifolius and var.tenuifolius, except one accession of the latter, differed in allozymes of AAT-D, ADH-C and FDH-A. — Cladistic analysis of the allozymic data as unordered absence-presence characters disclosed in the genus two major monophyletic species clusters: (1)P. polystachyus, P. ritensis, P. maculatus, P. marechalii, P. jaliscanus, P. salicifolius, P. lunatus, P. filiformis, P. angustissimus, P. acutifolius, P. coccineus, P. vulgaris, P. parvulus, P. pauciflorus, andP. pluriflorus; (2)P. grayanus, P. neglectus, P. pedicellatus, P. microcarpus, P. hintonii, andP. zimapanensis. P. xanthotrichus s. str. andP. zimapanensis are discriminated as paraphyletic, supporting their specific delimitation. — Phenetic analysis of the allozyme data with the UPGMA clustering revealed essentially the same pattern of genetic affinities between the species and additionally clarified the extent of allozymic divergence by taking into account species-specific and unique allozymes.  相似文献   

20.
Andreas Bick   《Zoologischer Anzeiger》2004,243(1-2):53-63
The fabriciin sabellid species, Fabricia nigra Langerhans, 1880 from the Macaronesian region, is assigned to the genus Pseudoaugeneriella Fitzhugh, 1998, based on information provided by newly collected specimens. The species is redescribed, including the variability of key characters. Moreover, structures of the anterior end — dorsal lips, ventral filamentous appendages, peristomial rings — of Pseudoaugeneriella nigra and other species of Fabriciinae are studied histologically and by means of SEM. The systematic significance of these characters in Fabriciinae is discussed.  相似文献   

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