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1.
Ferula coskunii H. Duman & M. Sağıroğlu sp. nov. from the Amanos Mountains (C6: Hatay-Turkey) is described and illustrated. It is closely related to F. drudeana Korovin, from which it differs mainly in habit, basal leaves, stem and mericarp features.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 357–361.  相似文献   

2.
On the evolution of basicranial articulations of birds, especially of fowl and waterfowl (Galloanseres) Basicranial articulations are among the most neglected structures of the avian feeding apparatus. Based on the presented ontogenetic evidence two nonhomologous types of basicranial articulations are distinguished in birds: 1. A basipterygoid articulation developing from an early embryonic quadratopolar comissure, which is homologous to the basipterygoid articulation of other amniotes. This diarthrosis is present in all paleognathous as well as in many juvenile and some adult neognathous birds. 2. A rostropterygoid articulation developing through apposition of the pterygoid on the parasphenoid. This secondary articulation is known from galliform and ansenform birds (Galloanseres). Based on ontogenetic evidence as well as functional analysis following hypothesis explaining the evolution of rostropterygoid articulations in the Galloanseres is proposed: 1. In the groundplan of birds (Aves, sensu Gauthier 1986) a basipterygoid articulation was present continuously during ontogeny. It protected the pterygoid-quadrate articulation against propalineal distortion by controlling the movement of the caudal end of the flexible, but undivided pterygopalatinal bar. This construction is preserved in recent paleognaths. 2. In the groundplan of the Neognathae an intrapterygoid joint subdividing the pterygopalatinal bar was formed in juveniles. Consequently the basipterygoid articulation had lost its function in adults and was therefore developed only in embryonic and juvenile stages. This condition is present in many recent neognaths. 3. In the stemline of the Galloanseres the intrapterygoid joint was already formed in embryos. Since an undivided pterygopalatinal bar is absent in any ontogenetic stage of the Galloanseres, no basipterygoid articulation is being formed. The recent Galloanseres retain this developmental pattern. 4. In the groundplan of the Galloanseres a newly developed rostropterygoid articulation was present providing a support for the pterygopalatinal bar. This articulation could withstand not only pressure but also increasing tension occurring as a consequence of the development of a gliding jaw joint and a firm grip with beak tips, both consequences of increasing herbivory in the Galloanseres. Since the basipterygoid articulation was reduced, a new secondary joint had to be developed.  相似文献   

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A new species of Viola (Violaceae) from north-western Yunnan, China, is described and illustrated. Viola dimorphophylla Y. S. Chen & Q. E. Yang sp. nov. is endemic to Zhongdian County, north-western Yunnan, and is very easily distinguishable from all other Chinese species of the genus by having obviously dimorphic leaves, with the basal ones being long petiolate, undivided and widely cordate, and the cauline ones sessile, linear and verticillate.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 115–119.  相似文献   

6.
Carpal evolution in diprotodontian marsupials   总被引:1,自引:0,他引:1  
Carpal anatomy in adults of 13 outgroup species and 50 diprotodontian species from all families except Tarsipedidae was examined, as well as a histological sectional series of a pouch young Vombatus ursinus . The results are discussed in the light of recent phylogenies, and functional aspects were considered to gain an understanding of carpal evolution in this diverse marsupial clade. Mapping of eight carpal characters on alternative diprotodontian phylogenies results in trees of similar lengths. Of the eight characters investigated, five characterize major diprotodontian clades and one offers an additional autapomorphy for the order. The occurrence of a prepollex varies across Diprotodontia, and for some species is polymorphic. Petauroids, Cercartetus and Trichosurus share the presence of a lunatum, a well-developed proximal process of the capitatum, a deep ulno-triquetral joint and a deep palmar process of the hamatum. Most macropodids are distinguished by the lack of a lunatum, lack of a proximal process of the capitatum, a short palmar process of the hamatum, a pointed ulno-triquetral articulation and a variably occurring groove in the scaphoid. The macropodines are set apart from the potoroines by their loss of a lunatum and a short palmar process of the hamatum. Two terrestrial clades, vombatiforms and macropodids, differ from the arboreal possums in similar aspects, indicating that carpal diversity might be related to function.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 369–384.  相似文献   

7.
With highly conserved morphology throughout the family, a tropical distribution, and no close living relatives, the trogons (Aves: Trogonidae) pose a difficult problem for systematists. Disjunct tropical distributions are often attributed to Gondwanan vicariance, but the fossil record for trogons is mostly from the Tertiary of Europe. This study examined support for the basal relationships among trogons using a combination of nuclear (RAG-1) and mitochondrial (ND2) DNA sequence data. Although some nodes could not be resolved with significant support, there is strong support for the basal position of three New World genera ( Pharomachrus , Euptilotis , and Priotelus ). This phylogenetic hypothesis differs markedly from previous studies of trogon relationships and taxonomic treatments. Biogeographically, it implies an origin and early vicariance events for the crown clade in the New World. Molecular divergence estimates place all of the basal nodes of the trogon phylogeny in the Oligocene, precluding a Gondwanan origin for modern trogons.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 725–738.  相似文献   

8.
Selaginella hainanensis X.C.Zhang & Noot. sp. nov. , a new species from Hainan Island, South China, is described and illustrated. Diagnostic notes and a key to the species distributed in Hainan are also provided.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 323–327.  相似文献   

9.
A new species, Achetaria latifolia V.C.Souza, is described and illustrated. It is characterized by its broadly ovate leaves, indument of stems and leaves of noncapitate hairs, and pubescent capsule. Achetaria latifolia is known only in the coastal dune-area of Cabo Frio region, Rio de Janeiro State, Brazil.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 73–75.  相似文献   

10.
Hybridization phenomena can be considered in different ways. Hybridization studies can be used to elucidate some aspects of speciation and adaptation. However, hybridization may be a threat to endemic species. Here, we studied bidirectional introgression between two sympatric species of Cyprinidae: Chondrostoma toxostoma toxostoma and C. nasus nasus . Analysis of morphology, allozymes and mtDNA sequences revealed that the hybridization between these two cyprinids takes different forms in the same river. The mosaic hybrid zone (so called because of the absence of a simple cline) appeared to be partitioned due to the proportions of the two species along a spatial scale. The proportion of each hybrid group in this zone was unstable over a 5-year period. We propose various protection/conservation states for the C. t. toxostoma populations based on the level of introgressive hybridization and the genetic structure of both species in 'pure' populations.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 135–155.  相似文献   

11.
The Balkan endemic species Microtus (Terricola) thomasi – Thomas' vole – is widely distributed in the Greek mainland and presents regionally confined karyotypic forms. In order to test the significance of geographical isolation and/or karyological differences in microevolutionary processes at the intraspecific level we used restriction enzymes and partial sequencing to study the polymorphism of the mtDNA d -loop control region in ten Greek populations. An overall high rate of both inter- and intrapopulation polymorphism was observed. The mtDNA diversity was unevenly distributed so that most of the populations studied were very similar and closely related, and only a few of them were clearly differentiated from the others. The mtDNA analysis failed to reveal any clear variation pattern that could be correlated with karyotypic forms or geographical proximity of the populations studied. Instead, the mtDNA phylogeny gave evidence in support of the coexistence of non-polymorphic (2 n  = 44) and polymorphic (2 n  < 44) karyotypic forms within the ancestral Greek M. (T.) thomasi stock. Interestingly, only one population (Agios Stefanos) seemed to significantly diverge from all the others in both methods used, forming a well-supported paraphyletic clade. Allozymic studies have already reported similar results, corroborating the genetic peculiarity of this population.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 55–68.  相似文献   

12.
A new species, Oxalis ferae Llorens, Gil & Cardona (Oxalidaceae) from the Balearic islands (Spain) is described and illustrated. It is considered to be endemic to Mallorca. The morphological differences between the more closely related taxa of Oxalis section Corniculatae are discussed. IUCN threatened category and observations on the ecology of the populations are noted.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 489–493.  相似文献   

13.
Orobanche icterica Pau, frequently regarded as a synonym for O. elatior Sutton, is lectotypified on Pau's original material from the herbarium of the Real Jardín Botánico in Madrid (MA 115079!). Its morphology is described with special emphasis on those characters which distinguish it from O. elatior. O. icterica is mainly found in the east of the Iberian Peninsula and sporadically in the south and north-west. It is considered to be close to O. elatior but deserving recognition at specific level.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 117–124.  相似文献   

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The gynostemium structure and ontogeny of two taxonomically disputed orchids, Hemipiliopsis (= Habenaria ) purpureopunctata and Senghasiella (= Habenaria ) glaucifolia , are described and illustrated by scanning electron micrographs. The early gynostemium ontogeny of Hemipiliopsis purpureopunctata is shown to be fundamentally similar to that of the species of the tribe Orchideae that have been previously studied. This includes the initiation sequence of sepals, petals and lip, form and orientation of anthers, three-lobed condition of median carpel apex, and presence of auricles and basal bulges. During the later developmental stages some differences occur. The stigma processes of Senghasiella glaucifolia are united into a tongue-shaped organ, and the lateral rostellum lobes of Hemipiliopsis purpureopunctata protrude forwards with their viscidia positioned above the spur-mouth. Based on gynostemium characters, the generic rank of Hemipiliopsis was confirmed, but that of Senghasiella was not supported.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 191–196.  相似文献   

17.
Ornithogalum chetikianum Uysal, Ertugrul & Dural sp. nov. (Liliaceae) is described and illustrated from Anatolia, Turkey. The species grows on alpine steppe and stony places in Bozkır (C4 Konya province) in South Anatolia. It is closely related to O. nutans L. and O. demirizianum Malyer & M.Koyuncu, an endemic confined to South Anatolia. Diagnostic morphological characters are discussed. Notes are also presented on the ecology, biogeography and conservation status of the new species.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 501–504.  相似文献   

18.
This study focused on the sequence variation in a mitochondrial region in house mice Mus musculus domesticus from chromosomally variable populations in the north-west Peloponnese, Greece. The mitochondrial molecular variation revealed was among the highest found so far for M. m. domesticus populations. The haplotype distribution pattern was rather complex. There was no clear differentiation between the populations characterized by Robertsonian chromosomes and standard all-acrocentric populations. There is therefore no indication that the Robertsonian populations were formed during a prolonged period of geographical isolation.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 84 , 643–651.  相似文献   

19.
A new species of the basal mosasaurid Halisaurus from the Late Cretaceous (Late Maastrichtian) of the Oulad Abdoun Phosphate Basin of Morocco is described on the basis of both cranial and postcranial remains. H. arambourgi sp. nov. is characterized by unique features of the nares, frontal, parietal, girdle and limb bones. A phylogenetical analysis supports the monophyletic status of Halisaurus ; H. platyspondylus (Maastrichtian, New Jersey), H. ortliebi (Maastrichtian, Belgium) and H. arambourgi form an unresolved polytomy. This study does not support the attribution of ' Halisaurus ' sternbergii (Santonian, Kansas) to Halisaurus nor to any known genus. A new genus, Eonatator , is proposed for the reception of this species, Eonatator sternbergii comb. nov. The new taxon Halisaurinae ( Halisaurus  +  Eonatator ) is the sister-group of more advanced mosasaurids (Natantia). Halisaurines are defined by the shape of the lateral premaxilla–maxilla suture; an oblique contact plane between the parietal and the supratemporal; a preaxial ridge present on the distal two-thirds of the radius length; and tibia and fibula long and slender with slightly expanded extremities.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 447–472.  相似文献   

20.
The Cainotheriidae are small artiodactyls that suddenly appeared in the late Eocene of western Europe. A revision of early Oligocene cainotheriid lineages is proposed on the basis of newly dated material from the Quercy Phosphorites (south-western France). A significant diversification of the group occurred at the end of the Eocene. Few species seem to have persisted through the Eocene/Oligocene boundary, but the Cainotheriidae subsequently diversified rapidly during the early Oligocene.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 145−166.  相似文献   

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