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1.
The phylogenetic relationships of the caryophyllidia-bearing dorids are studied, based on the examination of the type species of all the genera previously described. The phylogenetic hypothesis supports that the caryophyllidia-bearing dorids are a monophyletic group and the sister group of the clade formed by Astemnotus Ehrenberg, 1831 and Halgerda Bergh, 1880. Several genera previously considered as valid or regarded as uncertain are here synonymized: Peronodoris Bergh, 1904, Trippa Bergh, 1877, Phlegmodoris Bergh, 1878, Petelodoris Bergh, 1881, Kentrodoris Bergh, 1876, Audura Bergh, 1878, Centrodoris P. Fischer, 1883, Anisodoris Bergh, 1898, Awuka Er. Marcus, 1955, Rhabdochiia P. Fischer, 1883, Boreodoris Odhner, 1939, Dictyodoris Bergh, 1880, Gravieria Vayssiere, 1912, Aporodoris Ihering, 1886. The following genera are regarded as valid: Astemnotus, Atagema J.E. Gray, 1850, Jorunna Bergh, 1876, Platydoris Bergh, 1877, Diaulula Bergh, 1878, Rostanga Bergh, 1879, Halgerda Bergh, 1880, Baptodoris Bergh, 1884, Gargamella Bergh, 1894, Alloiodoris Bergh, 1904, Sclerodoris Eliot, 1904, Taringa Er. Marcus, 1955, Thorybopus Bouchet, 1977. The new genus Nophodoris is described based on two new species from New Caledonia deep waters. Two additional new species from New Caledonia belonging to the genera Atagema and Gargamella are also described. Nomenclatural and taxonomic problems are discussed, and several type species, neotypes and lectotypes are selected.  相似文献   

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The major organ systems of Goniodoris castanea were investigated by histological means, with an emphasis on those structures that are difficult to see by dissection. The species is characterized by some peculiar features that are unique or seldom within the Nudibranchia, such as the complete absence of specialized vacuolated cells, the presence of globular salivary glands, the presence of cuticular structures in the proximal intestine, a muscular sphincter around the distal vaginal duct, and the position of the blood gland closer to the pericardium than to the nervous system. Some of these characters are discussed in a phylogenetic context, although a thorough phylogenetic analysis is preliminary, due to lack of knowledge of probably related species.  相似文献   

4.
Paradoris , traditionally a generic taxon of discodorid sea slugs, is revised for the first time. One hundred and thirty specimens were examined, including all types and most of the nontype specimens available. New records for Paradoris are provided: South Africa, Tanzania, Seychelles, Western Australia, Thailand, Philippines, shallow waters of New Caledonia, southern Japan, and Hawaii. The individual variation of all taxonomic characters is thoroughly evaluated. Prior to the present study, Paradoris included 15 nominal species: 12 valid names and three synonyms. Three additional names, Discodoris erythraeensis , D. lora , and D. cavernae , are re-allocated to Paradoris , based on phylogenetic analysis. A phylogenetic diagnosis is provided for Paradoris : in particular, two new synapomorphies are described. Eight species names are regarded as valid: P. araneosa , P. dubia , P. erythraeensis , P. indecora , P. liturata , P. lopezi , P. mulciber , and P. tsurugensis . However, most of these species are poorly known, i.e. from very few specimens, and their taxonomic status might change when more individuals are available. P. lora is regarded as a nomen dubium . Six new synonymies are proposed, and explained by the fact that: (1) species names were created for one or a few specimens, without considering individual variation; (2) authors have not worked within a phylogenetic framework and have created new species names without considering all the existing species names already available within Paradoris . Three new morphospecies are described, but not formally named because their taxonomic status is still uncertain for several reasons (e.g. lack of knowledge of individual variation for some critical features).  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 125–238.  相似文献   

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Phylogenetic systematics (cladistics) is a theory of phylogeny reconstruction and classification widely used in zoology. Taxa are grouped hierarchically by the sharing of derived (advanced) characters. The information is expressed in a cladogram, a best estimate of a phylogeny. Plant systematists generally use a phenetic system, grouping taxa on overall similarity which results in many groups being formed, at least in part, on the basis of shared primitive characters.
The methods of phylogenetic systematics are used to create a preliminary cladogram of land plants. The current classification of land plants is criticized for its inclusion of many groups which are not monophyletic.
Objections to the use of phylogenetic systematics in botany, apparent convergences within major groups and frequent hybridization, are shown to be invalid. It is concluded that cladistic analysis presents the best estimate of die natural hierarchy of organisms, and should be adopted by plant systematists in their assessment of plant interrelationships.  相似文献   

8.
Summary

Several new taxa of the Clausiliidae were described From Turkey: Dobatia multidentifera n. sp., Albinaria monocristata n. sp., Albinaria basalifera n. sp., Roseniella (Chavchetia) n. subgen., Roseniella (Chavchetia) rufina n. sp., Armenica euprepes truncata n. ssp., Armenica multispirata n. sp., Armenica bicarinata grisea n. ssp., Kazancia n. gen., and Kazancia monticola n. sp. Investigations were made of the genital morphology of some species, and the arrangement of the taxa in Nordsieck’s classification (H, NORDSIECK 1979) is discussed.  相似文献   

9.
Prior to this study, the genus Heraeus Stål, 1862 included 14 species, all of which are restricted to the Western Hemisphere. Three species are known from the Nearctic Region, nine from the Neotropical Region, and two mainly tropical elements are distributed in both regions. In this contribution, we consider Heraeus cincticornis Stål, 1874 a junior synonym of Heraeus elegans (Walker, 1873), select a lectotype for Heraeus coquilletti Barber, 1914, and neotype for Lygaeus triguttatus Guérin‐Méneville, 1857, and describe 28 new species. In addition, the two new genera, Baranowskiobius gen. nov., to include H. elegans (Baranowskiobius elegans comb. nov.) and two new species, and Paraheraeus gen. nov., to include Heraeus eximius Distant, 1882 (Paraheraeus eximius comb. nov.), are described. Previously described species and new taxa are (re)described and illustrated, including male genitalia. Scanning electron micrographs, general habitus photographs, and distribution maps are included for all species studied. A phylogenetic analysis comprising 46 terminal taxa and 50 morphological characters was performed, and five species groups were hypothesized, including the coquilletti, caliginosus, guttatus, illitus, and plebejus groups. All known species of Heraeus and the new genera are included in the phylogenetic analysis. The type species of the genera Myodocha Latreille, 1807, Orthaea Dallas, 1852, and Paisana Dellapé, 2008 are used as out‐groups.  相似文献   

10.
中国近海共有海牛亚目(Doridacea)软体动物136种,隶属于23科49属,主要分布在浙江以南的热带、亚热带海区,有些种类向北可以分布到黄、渤海,少数种类仅分布于黄、渤海,属于印度-西太平洋区的中国-日本亚区。  相似文献   

11.
本文对狭义小奥德蘑属Oudemansiella s. str.的概念做了修订,在修订后的属中,狭义干蘑属Xerula s. str.的物种不纳入其中。在狭义小奥德蘑属下,提出了一个包含4个组O. sect. Oudemansiella、Mucidula、Dactylosporina 和 Radicatae的新系统。小奥德蘑组sect. Oudemansiella包括热带至南温带的一些物种,如新热带小奥德蘑O. platensis、澳洲小奥德蘑O. australis、旧热带小奥德蘑O. canarii和宽褶小奥德蘑O. crassifolia,这些物种的菌盖表皮为粘栅栏型,由菌丝组成,但其中常夹杂有链状排列的膨大细胞。粘蘑组sect. Mucidula包含北半球温带至亚热带的一些物种,如粘小奥德蘑O. mucida、网褶小奥德蘑O. venosolamellata和近粘小奥德蘑O. submucida,其菌盖表皮为粘子实层-栅栏型,由近棒状的顶端膨大细胞组成。小奥德蘑组和粘蘑组的物种,在外形和小生境上有相似之处,其担子果皆生于地表外的腐木上,菌柄上有或无菌环。刺孢组sect. Dactylosporina包含中南美洲那些孢子表面有指状凸起的物种。长根组sect. Radicatae由长根小奥德蘑O. radicata及其近缘种为代表,是该属中最大的组,包括该属其他三组之外的所有种。北美的O. americana、欧洲的O. caussei 和东亚的O. hongoi曾被置于小奥德蘑属中的白毛组O. sect. Albotomentosae或干蘑属的亮毛组X. sect. Hyalosetae,在本系统中它们没有纳入小奥德蘑属,因为它们可能代表一个单独的属。本文还提出了1新等级、32个新组合和1个新名称。  相似文献   

12.
Abstract: Eleven randomly chosen outcrops in the Miocene Pakhna Formation of Cyprus were sampled for holoplanktonic Mollusca. Four species of Heteropoda were found, and 24 of Pteropoda, a substantial increase from the two species recorded until now from the Miocene of Cyprus. One pteropod species, Peracle charlotteae sp. nov. (Gastropoda, Pseudothecosomata), is introduced. Age assignments based on holoplanktonic molluscs for the 11 localities are as follows: Langhian (Alassa 1–4), (Serravallian?) Tortonian to Messinian (Episkopi 1), Tortonian (Agios Tychon, Tokhni and the Maroni Marlstone of Khirokitia 1–2) and Tortonian to Early Messinian (Episkopi 2). These age determinations in some cases are at odds with those from previous publications based on calcareous nannofossils and Foraminifera. The sediments underlying the Amathus Channel outcrop yielded insufficient fauna for definitive dating, but we suggest are younger than Late Serravallian. At some localities, particularly in the Alassa area, pteropod assemblages are strongly variable on a bed‐by‐bed basis, and this offers possibilities for future refined biostratigraphical interpretations. This is the first substantial holoplanktonic mollusc fauna described from the eastern Mediterranean basin and allows correlation with assemblages in the central Mediterranean and elsewhere.  相似文献   

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Organismic diversity, as well as distributional and ecological patterns, can be fully understood in an evolutionary framework only. Reliable phylogenetic trees are required to ‘read history’, but are not yet available for most marine invertebrate groups. Molecular systematics offers an enormous potential, but still fails for ‘all‐species approaches’ on groups with species that are rare or occur in remote areas only, simply because there is no easily collectable material available for sequence analyses. Exploring morphologically aberrant corambid nudibranch gastropods as a case study, we assess whether or not morphology‐based phylogenetic analyses can fill this gap and produce a tree that allows a detailed view on evolutionary history. Morphology‐based parsimony analysis of corambids and potential relatives resulted in a well‐resolved and remarkably robust topology. As an offshoot of kelp‐associated onchidoridid ancestors, and obviously driven by the heterochronic shortening of life cycles and morphological juvenilization in an ephemeral habitat, the ancestor of corambids originated in cool northern Pacific coastal waters. A basal clade (the genus Loy) diverged there, adapting to live on soft bottoms under successive reversals of paedomorphic traits. The more speciose Corambe lineage radiated preying upon short‐lived encrusting bryozoa in a high‐energy kelp environment. Selection favoured transformation of the mantle into a cuticle‐covered shield, and successive paedomorphic translocations of dorid anal gills to the protected ventral side of the body, where compensatory, multiple gills evolved. Corambe species probably first colonized tropical American seas, and then radiated in worldwide temperate waters: this is explained by the excellent long‐distance dispersal abilities afforded by rafting on kelp, with the subsequent divergence of colonizers in allopatry. The competitive coexistence of Corambe pacifica MacFarland & O'Donoghue, 1929 and Corambe steinbergae (Lance, 1962) off California is the result of independent colonization events. The closing of the Isthmus of Panama separated the latter species from a flock that have radiated within warm Atlantic waters since then. Our case study shows that morphological structures, if investigated in depth, bear the potential for an efficient phylogenetic analysis of groups that are still elusive to molecular analyses. Tracing character evolution and integrating a wide range of geographic, biological, and ecological background information allowed us to reconstruct an evolutionary scenario for corambids that is detailed and plausible, and can be tested by future molecular approaches. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 585–604.  相似文献   

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A new species of Melibe is described based on two specimens collected in Florida. This new species is well differentiated morphologically and genetically from other species of Melibe studied to date. The four residue deletions in the cytochrome c oxidase subunit 1 protein found in all previously sequenced tropical species of Melibe sequenced (and Melibe rosea) are also present in this new species. These deletions do not appear to affect important structural components of this protein but might have fitness implications. This paper provides the first confirmed record of Melibe in the tropical western Atlantic Ocean.  相似文献   

17.
The genus Jorunna is characterized by a dorsum covered withcaryophyllidia, a prostate with two sections, a penis usuallyunarmed but occasionally armed with hooks, a copulatory spine,the presence of an accessory gland and a labial cuticle smoothor armed with jaw elements. The examination of 216 non-typespecimens, 30 types, and a review of the literature show thatthere are 16 valid species of the genus Jorunna: J. tomentosa(Cuvier, 1804); J. funebris (Kelaart, 1859); J. pantherinaAngas,1864; J. rubescens (Bergh, 1876); J. labialis (Eliot, 1908);J. parva (Baba, 1938); J. spazzola (Marcus, 1955); J. hartleyi(Burn, 1958); J. alisonaeMarcus, 1976; J. lemchei (Marcus, 1976);J. evansi (Eliot, 1906); J. pardusBehrens & Henderson, 1981;J.ramicolaMiller, 1996 and J. onubensis Cervera, García-Gómez& García, 1986. In addition, two new species fromthe Eastern Pacific are described: J. osae n. sp. and J. tempisquensisn. sp. We propose two new combinations: Jorunna parva and J.evansi. New records for the genus Jorunna are provided fromItaly, Algeria, Seychelles, Madagascar, Thailand, Marshall Islands,New Caledonia, Île de la Réunion, Sudan, PapuaNew Guinea, Indonesia, Panama, Costa Rica, Bahamas, and SouthernMexico. We present the first preliminary phylogenetic analysisof this cryptobranch dorid genus, based on morphological anatomicaldata, and discuss the biogeography and evolution of severalcharacters in this group. The phylogeny supports the hypothesisthat the genus Jorunna is a monophyletic group and shows thatKentrodoris is nested within it. (Received 31 December 2004; accepted 10 January 2008)  相似文献   

18.
This paper studies the phylogenetic relationships of the nudibranch dorids that lack a radula. Numerous specimens belonging to 29 different species, representing all genera of this group and other related taxa, were examined anatomically. Details of the foregut were examined with SEM. From this anatomical study a total of 62 characters were considered. These characters have been polarized using the genus Berthella as the outgroup. Eight species of dorids with a radula and the genus Armina have been also included in the analysis for comparative purposes. The phylogeny obtained supports the hypothesis that the radula has been lost once in the Doridina and that the radula-less dorids are a monophyletic group. Cryptobranchia is monophyletic when the radula-less dorids are included. The new genus Mandelia , introduced on the basis of a new species from South Africa, is the sister group of the rest of the radula-less dorids, and is described as a new family, Mandeliidae. The radula-less dorids (currently placed in a separate superfamily) actually constitute an internal branch of other cryptobranch dorids. Phyllidia has no synapomorphies that distinguish if from Fryeria , which has one autoapomorphy, the ventral position of the anus. Therefore, both genera are regarded as synonyms. The evolution of several characters among the radula-less dorids is discussed, and the present phylogeny is compared with prior studies.  相似文献   

19.
The Copionodontinae is described as a new subfamily of the neotropical catfish family Trichomycteridae. It comprises two new genera and three new species from north-eastern Brazil: Copionodon gen. nov. (including C. pecten sp. nov. and C. orthiocarinatus sp. nov. ) and Glaphyropoma gen nov. (including G. rodriguesi sp. nov. ) The Copionodontinae can be diagnosed externally by the anterior position of the dorsal fin, the presence of a well-developed adipose fin, and the strongly spatulate shape of the jaw teeth. The subfamily is hypothesized as monophyletic on the basis of several synapomorphies in internal and external anatomy. Copionodontines have the plesiomorphic condition of several characters, relative to all other trichomycterids, including the presence of ductus pneumaticus; the possession of separate pterosphenoids, sphenotics and prootics; the presence of the intercalarium; the complete infraorbital latero-sensory canal; the presence of the interhyal; and the wide lateral opening of the swimbladder capsule. Elsewhere within trichomycterids, these primitive traits are found only in Trichogenes. These and other characters support the hypothesis that copionodontines are the plesiomorphic sister group of all other trichomycterids, and that Trichogenes is their next successive sister group. Contrary to the currently accepted hypothesis, the monotypic Nematogenyidae is proposed as the sister group of the Trichomycteridae, and not of all remaining loricarioids. This change is to a major extent induced by the inclusion of copionodontines and Trichogenes in the analysis of lower loricarioid relationships. The present case is given as an example of the impact that undiscovered taxa, fossil or Recent, may have upon hypotheses of phylogenetic relationships.  相似文献   

20.
Abstract

The family Seguenziidae is represented in the New Zealand region by the following new species (fossil taxa asterisked): Seguenzia glabella*, S. prisca*, S. serrata*, S. conopia, S. fulgida, S. chelina, S. transenna, S. textilis, S. compta; Seguenziella (n.gen.) patula; Seguenziopsis (n.gen.) bicorona; Carenzia venusta, C. fastigiata; Thelyssina (n.gen.) sterrha; Ancistrobasis dilecta, A. regina; Fluxinella (n.gen.) lepida, F. lenticulosa, F. maxwelli*; Calliobasis (n.gen.) eos*, C. chlorosa, C. miranda.  相似文献   

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