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1.
Fossil species ofMelanopsis from a freshwater formation in the Jordan Valley (near Al-Qarn) were investigated and the deposits containing these species are formally described as Al-Qarn Formation. Four species were found:Melanopsis buccinoidea Olivier,M. tchernovi Heller & Sivan,M. costata Olivier andM. aaronsohni Blanckenhorn.Melanopsis costata was represented by two groups, “stepped” and “non-stepped”, the latter differing in its lower figurativity index. Intermediates were found betweenM. buccinoidea andM. tchernovi; they may be hybrids. TheMelanopsis assemblage bridges the faunal gap, in the Jordan Valley, between the 2 Ma lake of ‘Erq el Ahmar on the one hand and the 0.8–1.7 Ma lake of ‘Ubeidiya on the other. This suggests an early Pleistocene age of about 1.8 million years for the Al-Qarn Formation.  相似文献   

2.
The historic biogeography of the aquatic fauna of the Levant is reconstructed upon evidence of the gastropod groups with a well-established taxonomy and a rich fossil record. Faunal origins include ancient northern elements coming from an Anatolian–Iberian faunal province that, in the early Miocene, bypassed mainland Italy. This scenario is more plausible than the current 'Lago Mare' biogeographical theory. Palaeotropical elements represent either an Oriental or an African source; in either case these elements could have first reached Anatolia, from where they eventually spread southwards into the Levant, perhaps broadly coinciding in time with the invasion of the northern elements. Within the Levant, the faunas of the Euphrates, Orontes, and Jordan formed at first one common pool, but by 2 Mya the fauna of the Jordan had diverged from that of the Orontes; later, the Orontes fauna diverged from that of the Euphrates. By 1.4 Mya the fauna of the Levant consisted of both ancient survivors and new species. Some 780 000 years ago there was an exceptionally diversified fauna with many new, northern elements. Many of these elements did not survive to recent times. The fossil record suggests that the fauna of the Jordan Valley was separate from that of the Orontes throughout the Pliocene–Pleistocene. Taxa common today to the Jordan Valley and coastal sites may reflect an ancient system of rivers that drained westwards to the Mediterranean Sea, across the Jordan Valley of today.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 625–639.  相似文献   

3.
The taxonomic status of bent‐winged bats (Miniopterus) in the Western Palaearctic and adjacent regions is unclear, particularly in some areas of the eastern Mediterranean, Middle East and Arabia. To address this, we analysed an extensive collection of museum materials from all principal parts of this distribution range, i.e. North Africa, Europe and southwest Asia, using morphological (skull) and genetic approaches (mitochondrial DNA). Linear and geometric morphometric analysis of cranial and dental characteristics, together with molecular phylogeny, suggested that Miniopterus populations comprise four separate species: (1) M. schreibersii sensu strictissimo (s.str.) – occurring in Europe, coastal Anatolia, Levant, Cyprus, western Transcaucasia, and North Africa; (2) M. pallidus – occurring in inland Anatolia, Jordan, eastern Transcaucasia, Turkmenistan, Iran and southern Afghanistan (Kandahar); (3) a Miniopterus sp. – recorded from Nangarhar province in eastern Afghanistan, which we tentatively assign to M. cf. fuliginosus; and (4) a Miniopterus sp. with Afro‐tropic affinities confirmed from south‐western Arabia and Ethiopia, which we tentatively name M. cf. arenarius. The latter two species are well differentiated by skull morphology, while M. pallidus possesses very similar skull morphology to M. schreibersii. The results also suggest the existence of a possible new taxon (subspecies) within M. schreibersii s.str. inhabiting the Atlas Mountains of Morocco. © 2012 The Linnean Society of London  相似文献   

4.
Direct development and water dependence entail limited vagility in freshwater fauna. In these organisms, the population structure is probably linked to restrictions imposed by the habitat. In this study we investigate the relative contribution of processes stimulating the divergence of populations of Biomphalaria costata (Biese, 1951) and Biomphalaria crequii (Courty, 1907), two freshwater snails occurring in two contiguous and fragmented closed basins from the Andean Altiplano using mitochondrial DNA (cytochrome c oxidase subunit I) sequences, shell morphometric and radular morphology. In order to clarify the species boundaries, a third allopatric species was included: Biomphalaria aymara Valdovinos & Stuardo, 1991. Molecular analyses recovered two distinct clades: one composed of B. aymara from the Isluga swamps and B. costata from Spring 1 in Salar de Carcote, the single spring occupied by this species, and another integrated by snails from 12 springs spread across the Salar de Carcote and the Salar de Ascotán assigned to B. crequii, originally described from the Salar de Ascotán. Unlike shell morphometrics, radular morphology was informative for distinguishing these species. The division of the lineages occurred in the Late Pleistocene. A subclade that includes snails from the southernmost springs in Salar de Ascotán suggests fragmentation of the distribution of B. crequii associated with landscape discontinuities. In addition to microvicariance signals, the private haplotypes scattered around both salt spans show that close‐range dispersal is a common biogeographic process in this species. As evolutionary units, the single isolated and restricted population of B. costata has a high priority for conservation. © 2013 The Linnean Society of London  相似文献   

5.
Phylogenetic reconstructions using parsimony, maximum likelihood (ML), and Bayesian relaxed molecular clock analyses of ~2850 nucleotides of nuclear‐encoded small and large subunit ribosomal DNAs (SSU and LSU rDNAs) from 14 long‐looped (terebratelloid) ingroup and four short‐looped (terebratulidine) outgroup brachiopod taxa, together with ML analyses of ~663 nucleotides of mitochondrial cytochrome oxidase subunit 1 (cox1) from 12 terebratelloid taxa, show that deep divergence separates taxa endemic to waters in the vicinity of New Zealand from those with a Magellanic distribution around South America and Antarctica. This deep divergence also separates Magellanic Terebratella dorsata from New Zealand Terebratella sanguinea, showing that they are not congeneric. Instead, they belong to separate ‘Magellanic’ (MAG) and ‘New Zealand’ (NZ) clades that first diverged about 82 Mya (95% highest posterior density, 48–120 Mya), correlating with separation between the NZ and Antarctic tectonic plates. Sequence analyses also reveal (1) that the Antarctic endemic taxa Magellania fragilis and Magellania joubini are not congeneric with Magellania venosa, suggesting that their previous placement in Aerothyris should be restored, and (2) that divergence between Antarctic and NZ species of the terebratulide Liothyrella occurred much later than plate separation, perhaps because of continuing gene flow caused by long‐lived larvae. The topology of the rDNA and cox1 gene trees implies that radial ornament of the shell (‘ribbing’) has been gained (and/or lost) independently within the MAG and NZ clades. Radial ribs are widespread in articulate brachiopods throughout the Phanerozoic, but no comparisons of brachiopod rib morphology and morphogenesis have been published. Our comparisons of transverse shell mid‐sections in the scanning electron microscope reveal no obvious evidence of differences in morphology between independently gained ribs. We also consider several ways in which ribs may affect fitness, including effects on hydrodynamics. Only scanty and inconclusive evidence is available, but we suggest that effects (if any) are likely to be of small magnitude; adaptive value of brachiopod shell ribs remains to be demonstrated. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 631–645.  相似文献   

6.
'Ubeidiya is a 1.4 Myr-old Lower-Pleistocene site in the Jordan Valley. Its rich Melanopsis fauna was found to include five species: buccinoidea , costata, turriformis , phanesiana obediensis and multiformis . These species and their conchiometrics are described. M. buccinoidea and costata occur in the Levant also today whereas turriformis , p. obediensis and multiformis are extinct. These findings suggest considerable faunal connections between the Jordan, the Orontes and perhaps also Rodhos during the lower Pleistocene. During the late Miocene, when the Mediterranean Sea level dropped, coastal-plain freshwater habitats could have expanded and Melanopsis species could then have invaded the Rift Valley via coastal rivers. In addition they could have reached later, via the Rift Valley. Species frequencies of Melanopsis throughout 'Ubeidiya suggest three' Melanopsis landscapes': an early period dominated by buccinoidea , a later one by costata and an upper one by p. obediensis . It is reasonable to speculate that the buccinoidea landscape represents a spring or perhaps a deep lake with a nearby stream; the costata landscape a shallow, nonturbulent, well-aerated lake with a slow current; and the p. obediensis landscape a turbulent, well-aerated lake. Intermediates were found between buccinoidea and costata . Their low frequency and their chrono-distribution suggest they are hybrids, rather than evolutionary transitions between species. The 1.4 Myr old fossils of 'Ubeidiya may be the earliest direct evidence of hybridization among molluscs in nature, that is still going on today in the same region and aquatic system, among the same species. The Melanopsis hybrid populations may perhaps act as filters that prevent the introgression of most genes, but allow others to disperse into the range of the parent species. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 75 , 39–57.  相似文献   

7.
Posilović, H., & Bajraktarević, Z. 2010: Functional morphological analysis of evolution of ribbing in pliocene viviparid shells from Croatia. Lethaia, 10.1111/j.1502‐3931.2009.00209.x. This paper provides a functional analysis of Pliocene freshwater gastropods from the phylogenetic lineage of Viviparus neumayri to Viviparus ornatus. On this section of the phylogenetic line, it is possible to follow the continuous evolution of the shell ornamentation (shouldering and rib formation) from ancestral V. neumayri with smooth shell to V. ornatus with spiral ribs. The shell morphology and possible structural function of rib development is discussed from the analytical point of view, but also by Finite Element Modelling. Spiral rib development in the viviparids is not correlated with shell thickening, but rather with strengthening of the shell is achieved through development of spiral ribs, with direct biomechanical and evoloutionary significance. □Croatia, functional morphology, gastropod shell evolution, Pliocene, viviparid evolution.  相似文献   

8.
9.
A new species of Gesneriaceae, Paraboea trisepala W.H.Chen & Y.M.Shui, from a karst cave in Guangxi, China is described and illustrated. The new species differs from other species of Paraboea by its three‐lobed calyx. Variation in flower and inflorescence architecture was observed under cultivation. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 681–688.  相似文献   

10.
Por  F. D.  Dimentman  Ch. 《Hydrobiologia》2001,(1):335-339
In a relatively small area of 60 km2 which corresponds to the basin of the presently drained Lake Hula and its swamps (Upper Jordan Valley), 22 species of Cyclopoida are on record, with two more species reported in the pre-drainage times. The basin of Lake Hula is the southernmost enclave of permanent fresh waters in the Levant Province of Southwest Asia. Lacustrine and swamp environments existed in the area uninterruptedly for at least 700 000 years. A partial restoration project created a new lake. The basin is situated right in the middle of a main bird migration route. The fact that no less than 15 species were recorded from a set of small artificial and isolated experimental ponds seems to indicate that migrating birds and stocks of resting eggs are to account for this high diversity. Cyclops vicinus, Mesocyclops arcanus and Eucyclops serrulatus are the most common species. The success of the restoration is discussed.  相似文献   

11.
The worldwide distributed house mouse, Mus musculus, is subdivided into at least three lineages, Mus musculus musculus, Mus musculus domesticus, and Mus musculus castaneus. The subspecies occur parapatrically in a region considered to be the cradle of the species in Southern Asia (‘central region’), as well as in the rest of the world (‘peripheral region’). The morphological evolution of this species in a phylogeographical context is studied using a landmark‐based approach on mandible morphology of different populations of the three lineages. The morphological variation increases from central to peripheral regions at the population and subspecific levels, confirming a centrifugal sub‐speciation within this species. Furthermore, the outgroup comparison with sister species suggests that M. musculus musculus and populations of all subspecies inhabiting the Iranian plateau have retained a more ancestral mandible morphology, suggesting that this region may represent one of the relevant places of the origin of the species. Mus musculus castaneus, both from central and peripheral regions, is morphologically the most variable and divergent subspecies. Finally, the results obtained in the present study suggest that the independent evolution to commensalism in the three lineages is not accompanied by a convergence detectable on jaw morphology. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 635–647.  相似文献   

12.
The taxonomy of the endemic arboreal snail Satsuma albida species complex from Taiwan was unclear due to the animals' highly similar morphology, and their nocturnal and strict arboreal behaviour, leading to difficulties in collecting living specimens. This article is the first comprehensive comparative study on the systematics and taxonomy of this species complex using external morphology, anatomy of the reproductive system and molecular phylogeny. Consequently, two subspecies of S. albida are raised to species status, namely S. insignis and S. mollicula. Fourteen new species are also described. Fourteen of the 17 species showed polymorphism in banding pattern amongst populations and other species retained the whitish unity as seen in S. albida. Distributions of almost all taxa are geographically limited, with the exception of S. polymorpha sp. nov . The phylogeny of these species was reconstructed using 20 morphological characters and molecular data from the partial sequences of mtDNA CO1 and 16S rRNA genes, and the complete ITS2 sequence. The molecular phylogeny revealed three subclades (west, east and polymorpha clade) and revealed that these snails are monophyletic, originating from a ground‐dwelling ancestor. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 437–493.  相似文献   

13.
Subspecies lie at the interface between systematics and population genetics, and represent a unit of biological organization in zoology that is widely used in the disciplines of taxonomy and conservation biology. In this review, we explore the utility of subspecies in relation to their application in systematics and biodiversity conservation, and briefly summarize species concepts and criteria for their diagnosis, particularly from an invertebrate perspective. The subspecies concept was originally conceived as a formal means of documenting geographical variation within species based on morphological characters; however, the utility of subspecies is hampered by inconsistencies by which they are defined conceptually, a lack of objective criteria or properties that serve to delimit their boundaries, and their frequent failure to reflect distinct evolutionary units according to population genetic structure. Moreover, the concept has been applied to populations largely comprising different components of genetic diversity reflecting contrasting evolutionary processes. We recommend that, under the general lineage (unified) species concept, the definition of subspecies be restricted to extant animal groups that comprise evolving populations representing partially isolated lineages of a species that are allopatric, phenotypically distinct, and have at least one fixed diagnosable character state, and that these character differences are (or are assumed to be) correlated with evolutionary independence according to population genetic structure. Phenotypic character types include colour pattern, morphology, and behaviour or ecology. Under these criteria, allopatric subspecies are a type of evolutionarily significant unit within species in that they show both neutral divergence through the effects of genetic drift and adaptive divergence under natural selection, and provide an historical context for identifying biodiversity units for conservation. Conservation of the adaptedness and adaptability of gene pools, however, may require additional approaches. Recent studies of Australian butterflies exemplify these points. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??.  相似文献   

14.
Maytenus dongfangensis , a new species of Maytenus section Gymnosporia from Hainan Island, China, is described and illustrated. It is most similar to M. longlinensis, from which it differs in its glabrous rachis, deltoid sepals, 2 stigmas, and obconical capsules. A key to the species of Maytenus section Gymnosporia in China is provided. No claim to original Chinese Government works. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 534–538.  相似文献   

15.
The Levant is an important migration bridge, harboring border-zones between Afrotropical and palearctic species. Accordingly, Chameleo chameleon, a common species throughout the Mediterranean basin, is morphologically divided in the southern Levant (Israel) into two subspecies, Chamaeleo chamaeleon recticrista (CCR) and C. c. musae (CCM). CCR mostly inhabits the Mediterranean climate (northern Israel), while CCM inhabits the sands of the north-western Negev Desert (southern Israel). AFLP analysis of 94 geographically well dispersed specimens indicated moderate genetic differentiation (PhiPT = 0.097), consistent with the classical division into the two subspecies, CCR and CCM. In contrast, sequence analysis of a 637 bp coding mitochondrial DNA (mtDNA) fragment revealed two distinct phylogenetic clusters which were not consistent with the morphological division: one mtDNA cluster consisted of CCR specimens collected in regions northern of the Jezreel Valley and another mtDNA cluster harboring specimens pertaining to both the CCR and CCM subspecies but collected southern of the Jezreel Valley. AMOVA indicated clear mtDNA differentiation between specimens collected northern and southern to the Jezreel Valley (PhiPT = 0.79), which was further supported by a very low coalescent-based estimate of effective migration rates. Whole chameleon mtDNA sequencing (∼17,400 bp) generated from 11 well dispersed geographic locations revealed 325 mutations sharply differentiating the two mtDNA clusters, suggesting a long allopatric history further supported by BEAST. This separation correlated temporally with the existence of an at least 1 million year old marine barrier at the Jezreel Valley exactly where the mtDNA clusters meet. We discuss possible involvement of gender-dependent life history differences in maintaining such mtDNA genetic differentiation and suggest that it reflects (ancient) local adaptation to mitochondrial-related traits.  相似文献   

16.
Niche divergence or conservatism and phenotypic adaptation are important in lineage diversification. We used mitochondrial DNA (mtDNA), morphology and ecological niche models to examine these processes in three subspecies of Sage Sparrow (Artemisiospiza belli belli, A. b. canescens and A. b. nevadensis) that breed in bioclimatically diverse ecoregions in western North America. Overall, mtDNA and morphology are congruent with subspecies, ecoregion and bioclimatic niche. Niche divergence, rather than niche conservatism, accompanied by phenotypic adaptation, is associated with lineage diversification between subspecies. This diversification has occurred with and without physical barriers or accompanying genetic divergence. Populations of A. b. canescens are divided by a montane barrier into two bioclimatic regions (San Joaquin Valley, Mojave Desert), where they are indistinguishable phenotypically, but show distinctive genetic patterns. Although there is no physical barrier between A. b. canescens in the San Joaquin Valley and A. b. belli in the Coast Ranges, these populations occupy different bioclimatic niches and are phenotypically, but not genetically, diagnosable. Niche overlap is greatest between A. b. canescens from the Mojave Desert and A. b. nevadensis from the Great Basin, yet these subspecies maintain distinctive phenotypes and mtDNA, even in local secondary contact and sympatry. Palaeoclimatic niche models for the Last Glacial Maximum (c. 21 000 bp ) and the Last Interglacial (c. 120 000 bp ) suggest that ecoregionally distinct populations of Artemisiospiza belli experienced different Pleistocene range fluctuations and glacial refugia, with temporal niche conservatism. Populations probably reached their current distributions as favourable climates and habitats expanded after the last glaciation. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   

17.
Molecular systematics is bringing taxonomy into the 21st Century by updating our nomenclature to reflect phylogenetic relationships of taxa. This transformation is evidenced by massive changes in avian taxonomy, ranging from ordinal to subspecies changes. In this study, we employ target capture of ultraconserved elements to resolve genus‐level systematics of a problematic group of honeyeaters (Aves: Meliphagidae). With near complete species‐level taxon sampling of the Australo‐Papuan species within the traditionally recognized Meliphaga and Oreornis, we investigate generic limits using a genomic dataset. Likelihood and species tree methods confirm two clades within this group and found the New Guinea endemic Oreornis chrysogenys embedded within one of these clades. Our study supports earlier recommendations that Meliphaga Lewin, 1808 should be restricted to three species, M. aruensis, M. lewinii and M. notata. We make a case for recognizing three genera in the remaining species, Oreornis van Oort, 1910, Microptilotis Mathews, 1912 and Territornis Mathews, 1924.  相似文献   

18.
19.
Zusammenfassung Außer typischerVeronica chamaedrys L. findet sich in Österreich eine Sippe mit deutlich dichterer und kürzerer Behaarung der Sepalen, meist merklich tiefer eingeschnittenen Laubblättern, immer rein zweizeiliger Behaarung der Hauptachse und hellblauen, seltener rosa Blüten. Diese Sippe wurde auf Grund ihrer diploiden Chromosomenzahl (2 n=16) entdeckt und wird alsVeronica chamaedrys L. subsp.vindobonensis M.Fischer neu beschrieben. Sie wächst nur an trocken-warmen Standorten der Ebenen- und Hügelstufe, besonders im östlichen Österreich. Die weiter verbreiteteV. chamaedrys L. subsp.chamaedrys erwies sich dagegen als tetraploid (2 n=32); diese Chromosomenzahl entspricht den bisherigen Angaben für diese Art. Weitere Untersuchungen über den Formenkreis sind im Gange.
Summary Veronica chamaedrys L. subsp.vindobonensis M.Fischer, a new subspecies, differs from the type of the Linnean species by denser and shorter hairs on the sepals, deeply incised leaves and light blue or pink corolla; there are never hairs between the two rows of hairs on the primary stem. This new subspecies proved to be diploid (2 n=16), whereasV. chamaedrys subsp.chamaedrys is tetraploid (2 n=32) in accordance with all previous counts of the species. Subsp.vindobonensis occurs only in dry and warm habitats in low altitudes, especially in the eastern parts of Austria, while the typical subspecies prefers mesic meadows and woods from the plains up into the mountains.
  相似文献   

20.
Numerous studies have shown an association between aggressiveness and several other behavioural traits. For example, more aggressive animals were bold and active explorers tending to form persistent routines whereas less aggressive animals were shy, careful but more flexible. While the former are thought to be more successful under stable conditions the latter should have advantages in more dynamic situations. These differences can apply not only to individuals but also to populations, species or groups of species with important implications to species distributions and speciation rates. Here we utilized the Morris water task (MWT) to investigate how two subspecies, Mus musculus musculus and M. m. domesticus, known to differ in aggressiveness, cope with stressful situations. We found that less aggressive musculus males performed significantly better in solving the MWT than more aggressive domesticus males. This suggests that M. m. musculus is more flexible and could be more successful under stressful and/or dynamic situations typical of dispersal bouts. It seems plausible that this difference may have had an influence on the secondary contact between musculus and domesticus populations in the past and perhaps still can affect the dynamics of the European hybrid zone between the subspecies. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 310–319.  相似文献   

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