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1.
A new mantispid genus and species Symphrasites eocenicus gen. sp. nov. is described from the Middle Eocene of the Messel Pit fossil site, Germany. It has been placed, with confidence, in the subfamily Symphrasinae, the fossils of which were previously unknown. A review of the known fossil species of Mantispidae is provided, and their systematic placements are discussed. Liassochrysa stigmatica Ansorge & Schlüter, 1990 is assigned to Mantispidae, and therefore Liassochrysidae is a new synonym of Mantispidae; a second, more complete specimen of Mesomantispa sibirica Makarkin, 1997 is described from the Early Cretaceous Baissa locality, Russia; Mantispidiptera Grimaldi, 2000 is excluded from the family; Vectispa Lambkin, 1986 is referred to subfamily Mantispinae; and the assignment of Whalfera Engel, 2004 to Rhachiberothidae is validated. The origin and palaeobiogeography of the mantispids are briefly discussed: the concept of ousted relicts – which assumes that former widely distributed taxa were replaced with groups originating in the tropics – is assumed to best explain the present distribution of the family.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 701–716.  相似文献   

2.
Doradidae is a putatively monophyletic group of South American freshwater catfishes containing 30 extant genera and 72 valid species. Only one study to date has attempted to estimate phylogenetic relationships among doradids. This morphological analysis partitioned species into two basal genera ( Wertheimeria and Francisodoras ) and a crown group of three subfamilies (Platydoradinae, Astrodoradinae and Doradinae) whose relationships were unresolved. No subsequent work has been done to resolve the subfamilial trichotomy or to assess whether postulated intergeneric relationships are accurate. We address this problem with complete sequences (2.5 kilobases, kb) of mitochondrial 12S and 16S rRNA genes and partial (1.3 kb) sequences of the nuclear elongation factor-1 alpha (EF1α) gene from representatives of 23 doradid genera (43 species) and 13 outgroups from additional siluriform families. Phylogenetic analysis of these data yields strong support for the monophyly of Doradidae and Astrodoradinae (as well as other relationships), but otherwise shows significant conflict with morphological results. A partial re-examination of published morphological data indicates that many characters may have been incorrectly polarized and many taxa have incorrect state assignments. Our results provide a framework for ongoing efforts to describe the species-level diversity of this poorly understood neotropical family.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 551–575.  相似文献   

3.
A new species of Arabis L., A. erikii Mutlu sp. nov. , is described and illustrated. The species is restricted to inner Anatolia, south-west of Sivas. It grows on steppes. Diagnostic morphological characters are given for discrimination from the most similar taxa.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 251–256.  相似文献   

4.
A well-preserved pollen cone of the genus Ginkgo was found in the Yixian Formation (Early Cretaceous) of Liaoning Province, China, and is described as the new species Ginkgo liaoningensis . The pollen cone, catkin-like, consists of a main axis bearing scales at its base and spirally arranged sporophylls bearing 3–4 (−2) oval or elliptical sporangia. The sporangia are pendulous and dehiscent by a longitudinal slit. The mature pollen grains are monocolpate and elongate-elliptical, and the juvenile pollen grains are found in the tetrad stage. The characteristics of G. liaoningensis are very similar to those of the living Ginkgo biloba , but the sporophylls of G. liaoningensis bear 3–4 (−2) sporangia, whereas those of G. biloba bear mostly two sporangia. G. liaoningensis differs from fossil cones of Ginkgo huttoni from the Jurassic of Yorkshire, UK, and an unnamed specimen of Ginkgo from the Upper Cretaceous of Alberta, Canada, in the size and number of sporangia. The comparison between G. liaoningensis (fossil) and G. biloba (living) supports the reduction hypothesis of ovule organs in Ginkgo , with the number of sporangia having experienced the process of reduction from three or four to two since the Early Cretaceous.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 133–144.  相似文献   

5.
A data matrix is presented of 210 morphological characters (mostly osteological, some external) for 20 extant taxa of the ten Recent families of tetraodontiform fishes and 36 fossil tetraodontiforms. The oldest of these are from the Upper Cretaceous (95 Mya); most are from the Lower to Middle Eocene (50–58 Mya). There are two outgroup taxa (a zeiform and a caproid). A cladistic analysis of this matrix for only the extant taxa produced two equally parsimonious trees that call into question the monophyly of some of the previously accepted major higher-level tetraodontiform clades. Inclusion in the analysis of the large number of available fossil taxa helps to resolve relationships between family level clades. The new phylogenetic hypothesis, together with stratigraphic and biogeographical data, is used to discuss scenarios of the origin and evolution of the major clades of the order.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 565−617.  相似文献   

6.
Lecocarpus pinnatifidus is an endemic member of the Asteraceae occurring on only one island in the Galápagos archipelago. The capitula are large with female ray florets and male disc florets. They are self-compatible but this study suggests fruit set is pollen limited. Visits from Xylocopa darwini and other larger insect pollinators are rare, and small insects seem to be the main pollinators. Small insects carry few pollen grains and most likely mediate self-pollinations. Self-compatibility and seed set after selfing are the most common reproductive strategy in the Galápagos Islands and L. pinnatifidus seemingly fits well into this group.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 171–180.  相似文献   

7.
A new species of Ocimum , O. motjaneanum McCallum & K. Balkwill, endemic to serpentine soils in the north-west of Swaziland, is described and compared with O. obovatum, the species it most closely resembles. It has a very localized distribution with an area of occupancy under threat of encroachment by exotic trees and development, which makes it critically endangered (CR B1a + b(iii)) using the IUCN guidelines. We recommend habitat protection and incorporation of one site into an existing nature reserve to assure the continuation of this species.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 379–383.  相似文献   

8.
First record of fossil Mesozoic Ctenopoda (Crustacea, Cladocera)   总被引:1,自引:0,他引:1  
Pre-Pleistocene representatives of the crustacean order Ctenopoda Sars, 1865 are unknown. Here we describe Mesozoic fossil specimens of ctenopods from two localities in Mongolia: Khotont (Jurassic/Cretaceous boundary, about 145 Mya) and Khutel Khara (Lower Cretaceous, about 129 Mya). All specimens apparently belonged to the tribe Latonini Korovchinsky, 1986 of the subfamily Sidinae Baird, 1850. At the Khotont site, ctenopods were the most numerous microscopic animal fossils. We assigned these cladocerans to a new genus and species Archelatona zherikhini gen. nov., sp. nov. Our findings support a pre-Cretaceous origin for cladocerans.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 269–274.  相似文献   

9.
Water lilies and scarabs: faithful partners for 100 million years?   总被引:2,自引:0,他引:2  
Night-flowering water lilies (Nymphaeaceae) in South America are pollinated by Cyclocephala scarab beetles (Scarabaeidae: Cyclocephalini) in a specialized relationship involving synchronized flowering movements, strong floral scent, food tissues, and heat-producing flowers. We report that a similar and closely related association exists in West Africa between Nymphaea lotus L. and Ruteloryctes morio Fabricius (Cyclocephalini). This finding strongly supports a late Early Cretaceous origin of a symbiosis between the night-flowering water lilies and pollinating Cyclocephalini beetles. We believe that this is the first unambiguous evidence of a plant-pollinator relationship of this age.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 539–543.  相似文献   

10.
The suborder Amblycera (Insecta: Phthiraptera) comprises seven recognized families of parasitic lice. Three of these families (the Menoponidae, Laemobothriidae and Ricinidae) are present on a wide range of avian hosts. The four remaining families are restricted to a small section of mammals (the Boopiidae are parasites of Australian and New Guinean marsupials, and the Gyropidae, Trimenoponidae and Abrocomophagidae parasitize South and Central American rodents). This study uses a morphological approach to examine the evolutionary relationships between the genera from four amblyceran families: the Menoponidae, Boopiidae, Laemobothriidae and Ricinidae. Genera are represented by exemplars and a total of 44 louse taxa and one outgroup taxon were included. A cladistic analysis of 147 unordered characters recovered six equally parsimonious trees. Bootstrap, jackknife and Bremer support analyses were undertaken to assess the level of support for each resolved node in the strict consensus topology. Strong support was found for deep branch relationships between the families and in some cases for supra-generic groupings within families. The clades present in the strict consensus tree are discussed with reference to supra-generic and interfamily relationships, character choice, morphological convergence and host distribution. This study is the first phylogeny presented solely for amblyceran genera.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 138 , 39–82.  相似文献   

11.
This study aimed to identify potential factors responsible for geographically structured morphological variation within the widespread Australian frogs Limnodynastes tasmaniensis Günther and L. peronii Duméril & Bibron. There was support for James's rule, and both latitude and present climate explained large amounts of the variation in body size and shape (particularly in L. peronii ). There was also some support for the influence of several biogeographical barriers. Finally, both species were sexually dimorphic for body size and the degree of sexual size dimorphism (SSD) varied geographically. Climate was an important explanation for SSD variation in L. peronii , while latitude was most important for L. tasmaniensis . Geographical variations in sexual selection via male–male physical competition and climate-related resources are suggested as potential explanations for SSD variation in L. peronii .  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 82 , 39–56.  相似文献   

12.
The indumentum of Piriqueta and Turnera is made up of nine different types of trichomes, which broadly can be divided into glandular and non-glandular. Taking into account foot shape, head size and pedicle size, five variants of glandular trichomes are recognized: microcrapitate, stipitate-capitate, sessile-capitate and setiform. The non-glandular trichomes can be simple (unicellular or pluricellular-uniseriate), stellate or porrect-stellate. The setiform glandular hairs are present in most species of Piriqueta . Simple unicellular hairs are the most widespread type, frequently being found in combination with other trichomes. Stellate trichomes show a restricted distribution in both genera. Within Piriqueta , section Africana has only simple trichomes, whereas section Piriqueta has also porrect-stellate trichomes; groups of species can be set up according to the presence and type of glandular trichomes. Within Turnera the stipitate-capitate trichomes are exclusive to series Papilliferae ; sessile-capitate trichomes are found in series Microphyllae , Annulares and in some species of Salicifoliae ; clavate trichomes are found only in series Turnera ; setiform glandular hairs are exclusive to T. collotricha , whereas the microcapitate trichomes are widely distributed.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 85–97.  相似文献   

13.
We present a phylogenetic dating of asterids, based on a 111-taxon tree representing all major groups and orders and 83 of the 102 families of asterids, with an underlying data set comprising six chloroplast DNA markers totaling 9914 positions. Phylogenetic dating was done with semiparametric rate smoothing by penalized likelihood. Confidence intervals were calculated by bootstrapping. Six reference fossils were used for calibration. To explore the effects of various sources of error, we repeated the analyses with alternative dating methods (nonparametric rate smoothing and the Langley-Fitch clock-based method), alternative tree topologies, reduced taxon sampling (22 of the 111 taxa deleted), partitioning the data into three genes and three noncoding regions, and calibrating with single reference fossils. The analyses with alternative topologies, reduced taxon sampling, and coding versus noncoding sequences all yielded small or in some cases no deviations. The choice of method influenced the age estimates of a few nodes considerably. Calibration with reference fossils is a critical issue, and use of single reference fossils yielded different results depending on the fossil. The bootstrap confidence intervals were generally small. Our results show that asterids and their major subgroups euasterids, campanulids, and lamiids diversified during the Early Cretaceous. Cornales, Ericales, and Aquifoliales also have crown node ages from the Early Cretaceous. Dipsacales and Solanales are from the Mid-Cretaceous, the other orders of core campanulids and core lamiids from the Late Cretaceous. The considerable diversity exhibited by asterids almost from their first appearance in the fossil record also supports an origin and first phase of diversification in the Early Cretaceous.  相似文献   

14.
The evolutionary significance of the c . 1000-fold range of DNA C-values in angiosperms (1C =  c . 0.1–127.4 pg) has often attracted interest. A recent analysis, which superimposed available C-value data onto the angiosperm phylogeny, that placed Ceratophyllaceae as the most basal angiosperm family led to the conclusion that ancestral angiosperms were characterized by small genomes (defined as 1C £ 3.5 pg). However, with the recent increase in DNA sequence data and large-scale phylogenetic analyses, strong support is now provided for Amborellaceae and/or Nymphaeaceae as the most basal angiosperm families, followed by Austrobaileyales (comprising Schisandraceae, Trimeniaceae and Austrobaileyaceae). Together these five families comprise the ANITA grade. The remaining basal angiosperm families (Ceratophyllaceae, Chloranthaceae and magnoliids), together with monocotyledons and eudicotyledons, form a strongly supported clade. A survey showed that C-value data were scarce in the basal angiosperm families, especially the ANITA grade. The present paper addresses these phylogenetic gaps by providing C-value estimates for each family in ANITA, together with C-values for species in Chloranthaceae, Ceratophyllaceae and a previously unrepresented family in the magnoliids, the Winteraceae.  © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 175–179.  相似文献   

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16.
A revision of the three endemic Iberian species of Succisella G. Beck ( S. carvalhoana , S. microcephala and S. andreae-molinae ), based on herbarium studies, SEM photographs and field observations, is presented utilizing morphological, palynological, karyological, biogeographical and ecological characters. The distribution of the species in the Iberian Peninsula is shown in a grid map. Full synonymy is given for all taxa.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 351–364.  相似文献   

17.
A new species, Epipactis duriensis Bernardos, D. Tyteca, Revuelta & Amich is described and illustrated from north-east Portugal. Notes on its distribution, ecology, karyology, micromorphology and taxonomic relationships are presented as well as molecular data based on ITS analysis. A list of diagnostic differences between E. duriensis and the closely related species E. lusitanica and E. tremolsii is provided.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 239–249.  相似文献   

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20.
Recent revision of North African specimens of Isoetes velata A. Braun and the closely related taxon I. longissimum Bory, together with Spanish material conventionally designated I. longissimum , suggests that the Spanish specimens constitute a new species, I. fluitans . This is described and illustrated. The North African taxon I. longissimum is probably not specifically distinct from I. velata .  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 231–236.  相似文献   

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