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1.
Species of the Clivinematini genus Admetus Distant, 1883 are revised. A new species, A. quercicola, from Mexico, is described and figured. Admetus mexicanus and A. fimbriatus are redescribed and a key to species is provided.  相似文献   

2.
Three calcareous intercalations within lignite sequences in the open-cast mine Belchatów (51°15’N, 19°20’E) yield rich land snail faunas of over 40 species. Fission-track ages of these faunas (Be?-A and Bel-B) range from 18.1 ± 1.7 Ma to 16.5 ± 1.3 Ma, though the Be?-C level lies below the dated tuffitic intercalations and seems to be older. Five species of Cyclophoridae and Pomatiasidae are described including two new species:Procydotella?glazeki n. sp. andCaspicyclotus belchatoviensis n. sp.  相似文献   

3.
Eight species of the predatory gastropod Drupa are abundant in exposed habitats of Indo-Pacific coral reefs. The diets of seven species and two subspecies were investigated by gut content analysis of over 1400 specimens from a number of localities from the Red Sea to the western Pacific. Two species, D. grossularia and D. lobata, are sipunculan specialists, whilst D. morum and D. rubusidaeus mainly eat eunicid polychaetes. Drupa ricinus and probably D. elegans feed upon a wide variety of prey including crustacea, vermetid gastropods, chitons, polychaetes and sipunculans. The Red Sea subspecies D. ricinus hadari also eats small gobiid fish. Drupa clathrata clathrata, probably the least advanced species in the genus, has a diet of molluscs and barnacles, similar to that of other thaiid gastropods.  相似文献   

4.
Eight species of the predatory gastropod Drupa are abundant in exposed habitats of Indo-Pacific coral reefs. The diets of seven species and two subspecies were investigated by gut content analysis of over 1400 specimens from a number of localities from the Red Sea to the western Pacific. Two species, D. grossularia and D. lobata , are sipunculan specialists, whilst D. morum and D. rubusidaeus mainly eat eunicid polychaetes . Drupa ricinus and probably D. elegans feed upon a wide variety of prey including crustacea, vermetid gastropods, chitons, polychaetes and sipunculans. The Red Sea subspecies D. ricinus hadari also eats small gobiid fish. Drupa clathrata clathrata, probably the least advanced species in the genus, has a diet of molluscs and barnacles, similar to that of other thaiid gastropods.  相似文献   

5.
Summary The organization of Addisonia lateralis (Requien, 1848) and A. brophyi McLean, 1985 is described. Addisonia species have a thin, asymmetrical, cup-like shell and a very simple shell muscle. Eyes, oral lappets and epipodial tentacles are absent and the right cephalic tentacle is also used as a copulatory organ. Most characteristic is the enormously developed gill which is enlarged into the right subpallial cavity. It is composed of about 30 leaflets with skeletal rods and its epithelia are uniquely arranged. The heart is large and the single auricle is situated anteriorly left. There are two kidneys: the left is small, while the right forms large coelomic cavities and has no connection with the pericardium or the hermaphroditic genital system. Testis and ovary are separate: both have a simple duct proper (vas deferens, oviduct). They are connected to the copulatory organ by an open seminal groove; a small receptaculum is present. The mouth opening is typically triangular, with no jaws or subradular sense organs. Addisonia possesses tuft-like salivary glands, a radula diverticulum and distinct, tubular oesophageal glands. The oesophagus itself is simple. The radula and the posterior alimentary tract are unique; the stomach is completely reduced and the intestine forms a pseudostomach. The streptoneurous, hyoathroid nervous system has pedal cords with three commissures. The visceral loop is also cord-like. A single (left) osphradium is present and the small statocysts have several statocones.The peculiarities and unique combination of primitive and advanced characters in Addisonia reflect a highly enigmatic organization among the Archaeogastropoda. Possible relationships to other archaeogastropod groups are discussed.  相似文献   

6.
The anatomy of the Architectonicidae is described. The family combines prosobranch and pentaganglionate (=euthyneuran) traits, but has evolved in a very specialized way as cnidaria-feeders. There is no close relationship to the Epitoniidae, and the taxon 'Heterogastropoda' is regarded as artificial. The closest relatives of the Architectonicidae are the Mathildidae and the Pyramidellidae, all united in a taxon Allogastropoda. This taxon is regarded as a connecting link between basal marine Caenogastropoda and the most primitive Pentaganglionata (e.g. Acteon, Ringicula ). The relationships of the Architectonicidae to the Rissoellidae and Omalogyridae are briefly discussed.  相似文献   

7.
Nine species ofCarychium and one species ofCarychiopsis are described from calcareous intercalations within lignite sequences in the brown coal mine of Be?chatów. Three stratigraphically different levels (Be?-A, Be?-B and Be?-C) containing land snail remains have been referred to the biostratigraphic zones MN 4 — MN 9. Three new species are reported:Carychiopsis prisyazhnyuki, Carychium achimszulci andC. surai.  相似文献   

8.
A new deep water species from off the Chilean coast, Jerrybuccinum kantori sp. n., is described. The animal is equipped with a large statocyst. Kryptos explorator Fraussen & Sellanes, 2008 from off Concepción is found to be congeneric and transferred to the genus Jerrybuccinum. Differences in size and sculpture serve to distinguish the new species from J. explorator. Both Chilean species are associated with methane seep or low oxygen environments. They are compared with J. malvinense Kantor & Pastorino, 2009 and two still unnamed species from the Falkland Plateau.  相似文献   

9.
10.
A new fossil species of the pond snails (family Lymnaeidae Rafinesque, 1815), Lymnaea bogatschevi sp. n., from the Neogene (Khersonian–Maeotian transition) of southern Russia is described. It is characterised by a peculiar structure of the shell suture not found elsewhere in the family Lymnaeidae (both in living and extinct taxa). The suture of L. bogatschevi sp. n. may be described as a narrow groove that penetrates deep into the shell matter. This feature is developed both in protoconch and teleoconch whorls and is presented in several 100s of specimens that precludes its origin as an individual abnormality. There are no environmental factors known to induce such groove-like sutures in aquatic pulmonates indicating a genetic basis for this structure in L. bogatschevi. Also, we report a single shell with the similar channelled suture from a sample of Lymnaea megarensis (Gaudry in Fischer, 1867) from the Pliocene of Greece. It seems, in this species the groove-like suture was represented as a rare individual aberration, and later this trait disappeared completely from the lymnaeid morphological repertoir. Possible phylogenetic relationships between L. bogatschevi and the recent L. (Kazakhlymnaea) taurica (Clessin, 1880) are suggested and briefly discussed.  相似文献   

11.
12.
《Comptes Rendus Palevol》2019,18(4):442-448
The Rhinocerotidae material from the latest Miocene of Sahabi (Libya) is here revised in detail in order to clarify its systematic position and the paleobiogeographic implications. The family is represented by four specimens only at Sahabi, a phalanx, a mandible, a second upper molar (M2), and a second upper premolar (P2). Except for the phalanx, which can be only identified at the family level, the morphology and the dimensions of these specimens have revealed the presence of three taxa: Aceratheriini vel Teleoceratina, Brachypotherium lewisi and ‘Diceros’ sp. The presence of the large-sized Blewisi has been suggested in several papers, but without a detailed comparison or critical revision. The Brachypotherium from Sahabi also resembles Brachypotherium heinzelini, suggesting a probable synonymy between this species and Blewisi. A P2 from Sahabi differs from several species belonging to Ceratotherium, including Ceratotherium neumayri, and it resembles the genus Diceros. The rhinoceros association (Brachypotherium and a dicerotine) recognized at Sahabi has been recorded at Lothagam (Kenya), suggesting a biogeographic affinity with the eastern Africa assemblage.  相似文献   

13.
The distribution and content of tissue hemoglobins in the radular muscle, subradular cartilages, myocardium, and nerve tissue of gastropods are analyzed.  相似文献   

14.
Dental and horn core/antler morphology is discussed for some representative lower and middle Miocene pecorans in a review of the phylogeny and early zoogeography of the modern Old World families. Giraffes and bovids are more closely related than either is to deer. Andegameryx, Walangania and Teruelia are related to giraffoids plus bovoids together; Amphimoschus and Hispanomeryx are a probable sister group of bovoids; Propalaeoryx is the sister group of the giraffids plus climacoceratids. Procervulus and Lagomeryx may be closer to modern deer than are Stephanocemas and Dicrocerus but all are included in the Cervidae. The horn structure of Palaeomeryx has resemblances to giraffids, but its teeth and postcranial bones are more like cervids and it is placed in the Cervoidea. Pecorans seem to have evolved in Eurasia and there gave rise to deer. By the early Miocene some pecorans had entered Arabo‐Africa where they gave rise to giraffids and probably bovids. The relationships and zoogeography of the early bovids Eotragus, Homoiodorcas and Caprotragoides are likely to be important for later bovid history.  相似文献   

15.
Abstract

Eleven species of slug introduced into the New Zealand fauna are discussed: Testacellidae - Testacella haliotidea Draparnaud, 1801 (T. vagans Hutton, 1882 n.syn.); Arionidae - Arion intermedius (Normand, 1852), A. hortensis Férussac, 1819 (A. incommodus Hutton, 1879 n.syn.); Milacidae - Milax gagates (Draparnaud, 1801), M. budapestensis (Hazay, 1881), M. sowerbyi (Férussac, 1823); Limacidae - Deroceras reticulatum (Müller, 1774) (Limax molestus Hutton, 1879 n.syn.), D. panormitanum (Lessona & Pollonera, 1882), Limax maximus Linnaeus, 1758, Lehmannia flava (Linnaeus, 1758), L. nyctelia (Bourguignet, 1861). Of these, T. haliotidea, M. budapestensis, M. sowerbyi, D. panormitanum, and L. nyctelia are recorded from New Zealand for the first time. A key for the identification of these species is provided. Species thought to be doubtfully established are discussed, and a list is given of recent interceptions at New Zealand ports.  相似文献   

16.
The status of the Vetigastropoda, created 1980 to unite zeugobranch and trochoid archaeo-gastropods, is reconsidered and confirmed in the light of recent investigations. The most important synapomorphic characters of the Vetigastropoda are the ctenidial sense organs (so-called bursicles), the epipodial sense organs, and the special structure of the oesophagus. The conditions of the archaeogastropod oesophagus are comparatively described.
An examination of the relationships of the Vetigastropoda establishes the archaeogastropod nature of the Architaenioglossa. It also demonstrates the monophyletic origin of all higher gastropods, including the Caenogastropoda (s.str.) as well as the Pentaganglionata (= Euthy-neura). The Campanilidae, Valvatidae, Rissoellidae, Omalogyridae, and the Allogastropoda (= Architectonicoidea and Pyramidelloidea) share characteristics with both of the above-mentioned groups, but cannot be classified within any of them. These groups are regarded as subsequent offshoots between the caenogastropod and the pentaganglionate level of organization. The level of Archaeogastropoda is redefined by the hypoathroid/dystenoid nervous system and simple tentacle nerves; the remaining Streptoneura are classified as Apogastropoda with epiathroid nervous system, parapedal commissure, and bifurcated tentacle nerves.  相似文献   

17.
18.
Three species of the arcto-boreal, large gastropod Neptunea , described by Linnaeus in 1758 and 1771, occur in large numbers over wide areas of the inshore North Atlantic and adjacent Arctic seas and are conspicuous among Pliocene and Pleistocene molluscs in the Icelandic, North Sea, and western Mediterranean basins. Selections of lectotypes for these species from shells in the collection of the Linnean Society of London, and designations of their type localities, establish the identity of Linnaeus' neptunes and more accurately determine their geographic and geologic distribution. The geographic range of Neptunea (Neptunea) antiqua (L.), the type species, now extends from southern Norway to the northern Biscay coast of France and from the westernmost Baltic Sea to southwestern Ireland; this species also occurs in Pliocene-Holocene marine deposits in West and East Germany, Sweden, the Netherlands, England and France. Its type locality is determined to be the North Sea. N. (Neptunea) despecta (L.) lives in the eastern Canadian Arctic, off southern Greenland, the Barents Sea, and North Atlantic as far south as Massachusetts and Portugal; it also occurs in Pliocene-Holocene strata of eastern Canada, east-central Greenland, Norway (including Svalbard), the Soviet Union, Sweden and England. Its type locality is determined to be the postglacial deposits at Uddevalla in southwestern Sweden. N. (Sulcosipho) contraria (L.) now extends from the southern Biscay coast of France to Cape Spartel, Morocco; this species also occurs in Pleistocene and lower Holocene sequences of the western Mediterranean. Its type locality is determined to be Vigo Bay, Spain. A closely related fossil species, N. (S.) angulata (S. V. Wood), occurs in Pliocene and Pleistocene deposits of the North Sea basin.  相似文献   

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20.
Ohne Zusammenfassung
Statocyst function in some pulmonate gastropodsBehavioral and electrophysiological studies

Herrn Prof. Dr. F. Huber danke ich für das Thema. Die Untersuchungen wurden gefördert durch ein Promotionsstipendium der Stiftung Volkswagenwerk und des Landes Nordrhein-Westfalen sowie aus Mitteln der Deutschen Forschungsgemeinschaft und der Stiftung Volkswagenwerk, die Herrn Prof. Huber zur Verfügung standen. Herrn Prof. Dr. H. Schöne danke ich für die Durchsicht des Manuskriptes und meiner Frau für ihre Hilfe bei einigen Messungen.  相似文献   

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