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1.
2.
We report on and name two new taxa of basal crocodylomorph archosaurs from the Lower Jurassic, Litargosuchus leptorhynchus gen. et sp. nov. , from the upper Elliot Formation (Stormberg Group) of South Africa, and Kayentasuchus walkeri gen. et sp. nov. , from the Kayenta Formation (Glen Canyon Group) of Arizona, USA. Examination of this material led to a reconsideration of basal crocodylomorph interrelationships. A phylogenetic analysis found no support for the monophyly of Sphenosuchia.  © 2002 The Linnean Society of London. Zoological Journal of the Linnean Society , 2002, 136 , 77–95.  相似文献   

3.
Five palm flowers in Dominican amber and one in Baltic amber are described or characterized. Palaeoraphe dominicana gen. et sp. nov. in the subtribe Livistoninae, is described from one perfect flower in Dominican amber. Roystonea palaea sp. nov. is described from one staminate and one pistillate flower in Dominican amber. Three other palm flowers, two perfect flowers from Dominican amber and one staminate flower from Baltic amber, are briefly characterized and figured.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 361–367.  相似文献   

4.
Clivia robusta B.G. Murray, Ran, de Lange, Hammett, Truter et Swanevelder sp. nov. (Amaryllidaceae) is a tubular, pendulous-flowered Clivia species, restricted to the Pondoland Centre of Endemism, South Africa. The unique morphology, distribution, karyotype and molecular fingerprint distinguish it from all other pendulous-flowered species in the genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 369–374.  相似文献   

5.
Abstract:  A diverse fauna of three-dimensionally preserved sponges is described from nearshore volcanogenic sandstones near Llandrindod, Mid-Wales. The fauna was preserved through early marginal silicification, in rare examples with silicification of soft tissue, and includes aspicular and spicular demosponges, hexactinellids, and a heteractinid. The fauna is largely endemic, with the following new species, genera and families erected: Onerosiconcha gregalia gen. et sp. nov., Ordinisabulo quadragintaforma gen. et sp. nov., Miritubus erinaceus gen. et sp. nov., Vadosifistula milvus gen. et sp. nov., Polycornua trescelestus gen. et sp. nov. (Pseudolanciculidae fam. nov.), P. entropus sp. nov., Palaeocallyoides improbabilis gen. et sp. nov., Reticulicymbalum tres gen. et sp. nov., Triactinella rigbyi gen. et sp. nov. (Triactinellidae, fam. nov.), Spissiparies minuta gen. nov., Brevicirrus arenaceus gen. et sp. nov., Pyritonema scopula sp. nov. (Pyritonemidae, fam. nov.) and Microastraeum tenuis gen. et sp. nov. In addition, Pseudolancicula Webby and Trotter is recorded outside Australia for the first time, although only as isolated spicules. The environment represented by this fauna has not previously yielded articulated sponges, and thus the apparent endemism may be misleading.  相似文献   

6.
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   

7.
The species of Scleropactidae from America are revised and redescribed. A phylogeny hypothesis based on an analysis of morphological characters is presented. The genera are redefined and the generic placement of several species is corrected. The Neotropical Scleropactidae include Colomboscia , Scleropactes , Circoniscus , Neosanfilippia , Sphaeroniscus , Richardsoniscus , Spherarmadillo , Colomboniscus , Amazoniscus and Protosphaeroniscus . The genus Chileoniscus is excluded from the Scleropactidae. Sphaerobathytropa is excluded from the Scleropactidae and its previous record from Argentina is revealed to be erroneous. Synuropus is revalidated and excluded from the Scleropactidae. The following new genera are introduced: Scleropactoides gen. nov. , Globopactes gen. nov. , Caecopactes gen. nov. , and Troglopactes gen. nov. Thirteen species are described as new: Caecopactes minimus sp. nov. , Colomboscia parva sp. nov. , Globopactes falconensis sp. nov. , Globopactes hispidus sp. nov. , Globopactes meridae sp. nov. , Scleropactes cotopaxii sp. nov. , Scleropactes ecuadoriensis sp. nov. , Scleropactes pululahua sp. nov. , Scleropactoides curvatus sp. nov. , Circoniscus hirsutus sp. nov. , Sphaeroniscus quintus sp. nov. , Spherarmadillo nebulosus sp. nov. , and Chileoniscus armadillidioides sp. nov. Identification keys to all species are provided.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 (Suppl. 1), 1–339.  相似文献   

8.
Both sexes of a new species of Taurocletodes Kunz, 1975 (Copepoda, Harpacticoida, Canthocamptidae incertae sedis ) are described from sandy beaches along the Black Sea coast of Turkey. The genus Taurocletodes is removed from its synonymy with Parepactophanes Kunz, 1935 and re-instated as a valid genus, accommodating the type species T. dubius (Noodt, 1958) comb. nov. and T. tumenae sp. nov. Both genera can be differentiated by major differences in the segmentation of P1–P3 endopods, the absence/presence of penicillate setae on P1 endopod, the number of outer spines on P2–P4 exp-3, the armature of P2–P4 endopods and the sexual dimorphism of P2 endopod and P3 exopod. T. tumenae sp. nov. and T. dubius are morphologically very similar, differing in morphometric characters related to the endopodal segmentation of P1 and P4, and armature of the male P5. The controversial taxonomic status of Parepactophanes and Taurocletodes within the family Canthocamptidae is discussed.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 469−486.  相似文献   

9.
Fissarcturus bathyweddellensis sp. nov. and Fissarcturus sandwichi sp. nov. are described from the abyssal Southern Ocean near the Antarctic Peninsula and Fissarcturus rossi sp. nov. is described from the shallow Ross Sea. A list of all described species of Fissarcturus is given. The new species differ from recognized species of the genus in the following respects: F. bathyweddellensis can be distinguished based on spination on the dorsum of the body, which is described in detail herein. It is most similar to F. emarginatus Brandt, 1990, but this has, for example, a shorter and less stout second cephalic spine. F. rossi can also be distinguished from F. bathyweddellensis based on spine pattern. Whereas all dorsal spines of F. bathyweddellensis are smooth, those of F. rossi are covered with spinules. F. sandwichi can be distinguished from the other species of the genus by the strong frontally bent supraocular spines (females with second cephalic spines) and dorsal body surface, which is covered with flat, cauliflower-like elevations in submedial, lateral and coxal rows.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 263–290.  相似文献   

10.
A new vascular plant, Hsüa deflexa sp. nov., is documented from the Lower Devonian ((upper) Pragian-lower Emsian) Xujiachong Formation, near Xujiachong village, Qujing District, eastern Yunnan, South China. In three dimensions, the branching system comprises a robust creeping main axis and comparatively slender erect lateral axes inserted oppositely or alternately. The lateral axes depart at right angles from the main axis. Towards the apex, the main axis is perhaps erect with the lateral axes attached at smaller angles. The lateral axes dichotomize equally one to three times in different planes and decrease in diameter and length acropetally. They bear sparse and irregular tiny spines. Apices of a pair of distal lateral axes curve in opposite directions and each terminates in a rounded to reniform sporangium. The sporangium dehisces into two equal valves along an indistinct convex marginal thickening. The xylem is possibly centrarch. This plant fits Hsüa in branching pattern, sporangial characters and xylem maturation. Hsüa deflexa sp. nov. differs mainly from the type species H.  robusta in the presence of axial spines, perpendicular extension of lateral axes from the main axis and curving of distal lateral axes. Based on the possibly centrarch xylem and terminal sporangium, this plant relates to the rhyniophytes ( sensu Banks, 1968). In view of the equal sporangial valves with marginal thickenings it resembles the zosterophyllophytes ( sensu Banks, 1968). Hsüa is now treated as incertae sedis .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142 , 255−271.  相似文献   

11.
East Africa has a reduced mangrove crab species richness when compared to Asian mangroves. To date, only one species of Perisesarma de Man, 1895 has been reported in East Africa, despite more than 30 years of mangrove research in this region. Based on morphology, colour, mtDNA and behaviour, we describe a new species of Perisesarma from Kenya, P. samawati sp. nov. Surprisingly, when comparing molecular data from other species within this genus, P. samawati sp. nov. and the sympatric P. guttatum (A. Milne Edwards, 1869) are not sister species. Some aspects of the ecology of P. guttatum and P. samawati sp. nov. are compared and the differences discussed. Additionally, we compare P. samawati sp. nov. with the ecological literature of a possible sister species P. eumolpe de Man, 1895 from Malaysian mangroves. Our findings suggest that the new species is an ecologically important species in East African mangroves.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 435–445.  相似文献   

12.
Stomion is one of three speciose and taxonomically difficult genera of flightless Darwin's darkling beetles of the Galápagos Islands. The previously named species and subspecies of Stomion are analysed by morphometric and cladistic methods. Eleven species are here recognized, which probably descended from colonization by a single ancestral species. Cladistic analysis yielded two weakly supported clades that are different from previously published morphological and allozyme genotype groups. Phenotypic and genotypic characters may be evolving independently. There is much within-species variation, but there is no compelling evidence of adaptive radiation in Stomion , in contrast to that in the famous Darwin's finches. The analyses show the need for changes in morpho-species taxonomy: S. punctipennis Van Dyke ( syn. nov. ) is elevated to full species from a subspecies of S. galapagoensis Waterhouse. There is no evidence to support the validity of: S. laevigatum santacruzensi Franz ( syn. nov. ), synonomized here under S. l. laevigatum Waterhouse; S. galapagoensis leleupi Kaszab ( syn. nov. ), synonomized here under S. linelli Blair; S. galapagoensis pinzoni Franz ( syn. nov. ), synonomized here under S. obesum Van Dyke. S. genovesa sp. nov. is described from Genovesa Island. Lectotypes are designated for S. galapagoensis Waterhouse, S. laevigatum Waterhouse and S. helopoides Waterhouse .   © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 135–152.  相似文献   

13.
OCTOCORALLIAN AND HYDROID FOSSILS FROM THE LOWER ORDOVICIAN OF WALES   总被引:1,自引:1,他引:0  
Abstract:  Octocorallian and hydroid fossils are described from the Lower Ordovician (Arenig Series) of Wales. They include gorgoniids that are the earliest known fossils of this group: Petilavenula varifurcata gen. et sp. nov. and P. surculosa gen. et sp. nov. Pennalina crossi gen. et sp. nov. is probably also a gorgoniid but may be a hydroid. A new hydroid, Pontifennia gracilis gen. et sp. nov., is also described.  相似文献   

14.
The family Thryonomyidae is known from the Eocene up to the present. Today, this group comprises just two closely related species, which are restricted to sub-Saharan Africa. However, various thryonomyids have been recorded in strata of Miocene age, when the group spread out of Africa eastward to southern Asia (Pakistan). A systematic revision and a cladistic analysis shows that 20 species can be referred to this family: Thryonomys swinderianus (Temninck), T. gregorianus (Thomas), Paraphiomys pigotti Andrews, P. occidentalis Lavocat, P. simonsi Wood, P. hopwoodi Lavocat, P. shipmani Denys et Jaeger, P. australis Mein, Pickford et Senut, P. roessneri Mein, Pickford et Senut, P. afarensis Geraads, Paraphiomys sp. nov. from Saudi Arabia López-Antoñanzas et Sen , P. renelavocati sp. nov. , Neosciuromys africanus Stromer, Apodecter stromeri Hopwood, Paraulacodus indicus Hinton, Paraulacodus johanesi Jaeger, Michaux et Sabatier, Gaudeamus aegyptius Wood, Epiphiomys coryndoni Lavocat, Kochalia geespei (de Bruijn et Hussain), Paraphiomys sp. nov. from Saudi Arabia, and Paraphiomys orangeus Mein et Pickford. The unresolved basal position of Sacaresia moyaeponsi with respect to Metaphiomys schaubi and the clade comprising the above-cited species, suggest that this taxon should not be allocated to the family Thryonomyidae. A phylogenetic definition of the family Thryonomyidae is proposed as an outcome of the phylogenetic analysis: Epiphiomys corindoni , Thryonomys swinderianus , their most recent common ancestor and all its descendants (node-based taxon).  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 423–444.  相似文献   

15.
Three new species, Acantholimon bashkaleicum sp. nov. , Acantholimon artosense sp. nov. and Acantholimon hoshapicum sp. nov. (Plumbaginaceae) are described and illustrated. The species are all confined to B9/B10 Van Province in East Anatolia where they grow either on calcareous mountain slopes or on mountain steppes. Diagnostic morphological characteristics from the closely related species are given, along with a discussion dealing with their taxonomic relationships, and their conservation statuses are pointed out. A revised key to the Acantholimon species with heterophyllous leaves, two or more flowered and four or more bracteated spikelets is also provided.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 497–505.  相似文献   

16.
17.
Excellent three dimensional preservation of 142 specimens of Alanops magnificus gen. et sp. nov. (Chelicerata: Xiphosura) from the Stephanian Konservat-Lagerstätte of Montceau-les-Mines (Saône-et-Loire, France), exposes the carapace design and hitherto unrecorded details of fossil xiphosuran ventral anatomy, and makes possible an interpretation of appendicular functional morphology. All legs are long, slender and chelate. The chelate condition of the fifth leg and the shape of the prosoma (highly vaulted with a subvertical frontal area) indicate that the animal was neither a burrower like Recent xiphosurans (e.g. Limulus ) nor an active swimmer as suggested for other extinct forms, but was more likely to have been a benthic crawler. The ability to fold up is attested by both partly enrolled specimens showing appendages withdrawn into the prosomal cavity, and by coaptive devices on the external and internal margins of both prosoma and opisthosoma. The low-level articulation system at the boundary between the two shields allowed both the carapace closure and the complete outstretching of the animal. The unusually small adult size of Alanops magnificus gen. et sp. nov. combined with the loss of ophthalmic ridges and spines is interpreted as indicating a paedomorphic derivation from a bellinurine stock. The depositional environment (limnic intramontane basin) and faunal association (dominated by syncarids and bivalves) of Alanops indicate that the animal probably lived in fresh water.  相似文献   

18.
The spider genus Metabus (Tetragnathidae) previously included nine species: the type M. gravidus O. P.-Cambridge, 1899 – junior synonym of Leucauge ocellata (Keyserling) – from Central America and eight species from Chile. In this paper, the classification of the Metabus species-complex is revised, and two new genera, with three new species and five new combinations, are described. Allende gen. nov. is created for four Chilean species not congeneric with the type of Metabus : the type A. puyehuensis sp. nov. , A. patagiatus (Simon) comb. nov. , A. nigrohumeralis (F. O. P.-Cambridge) comb. nov. and A. longipes (Nicolet) comb. nov. Further additions to the Chilean fauna are under the new genus Mollemeta gen. nov. – created for M. edwardsi (Simon) comb. nov. – and three new species of Chrysometa : C. acinosa sp. nov. , C. levii sp. nov. and C. maitae sp. nov. Metabus now includes four species: M. ocellatus (Keyserling) comb. nov. , M. debilis (O. P.-Cambridge) comb. nov. , M. ebanoverde sp. nov. and M. conacyt sp. nov. All of these species were included in a phylogenetic analysis of 38 tetragnathid and 12 orbicularian outgroup terminals scored for 105 morphological and behavioural characters. The results suggest that Metabus as previously circumscribed is polyphyletic. The phylogenetic relationships within tetragnathids are briefly discussed. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 285–335.  相似文献   

19.
Hybodontoid and nonhybodontoid sharks are described from the Lower Triassic Vega‐Phroso Siltstone Member of Sulphur Mountain Formation on the basis of newly discovered material. The age of the classic fossil site ‘Wapiti Lake’ in the Canadian Rocky Mountains is discussed on the basis of new field data and one conodont found in association. Preliminary results suggest that these elasmobranch remains are between early Smithian and Spathian in age. Apart from the enigmatic genus Listracanthus and previously reported edestoids, the shark fauna consists of at least one hybodont, at least two questionable hybodontoid genera and an elasmobranch of enigmatic affinities, represented by peculiar denticles only and described as ‘genus A’incertae sedis. The presence of the only previously reported hybodont genus, cf. Palaeobates, is erroneous. The largest specimen represents the most complete Early Mesozoic shark known. The heterodonty of its dentition, fin spine morphology and the short, robust body shape imply it represents a member of a new family of shark, Wapitiodidae fam. nov. , and is described here as Wapitiodus aplopagus gen. et sp. nov. The unique dental morphology shows affinities to Polyacrodus but clearly differs in the complete lack of side cusps. Wapitiodus gen. nov. possesses a primitive fin spine structure. The tooth crowns are entirely blunt in the distal (posterior) tooth files, and are acuminate‐unicuspid in several anterior files. Tooth morphology, the shape of the basal cartilages, the proximal insertion of the fin spines and the pectoral fin structure are interpreted as diagnostic characters for this new genus, and possibly for the Wapitiodidae fam. nov. The majority of observed characters appear to be primitive and are reminiscent of Palaeozoic sharks, however, and these features include dorsal fin spine morphology and gross skull anatomy. A second species, provisionally placed in the same genus, is described as Wapitiodus homalorhizo sp. nov. Wapitiodus homalorhizo sp. nov. can be distinguished from W. aplopagus gen. et sp. nov. by the proportions of the fin spines, tooth morphology and possibly the body shape. Several isolated teeth and other fragmentary material are referred to either Wapitiodus gen. nov. sp. indet. or to ?Polyacrodus sp. (Polyacrodontidae gen. et sp. indet.). A third genus of elasmobranch (incertae sedis) is described as ‘Genus A’ and is recognized by its peculiar scales. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149 , 309–337.  相似文献   

20.
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   

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