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1.
ABSTRACT. We discovered a free‐living peritrich ciliate with outstanding features in the River Rhine. Its morphology and 18S rRNA gene sequence were studied with standard methods. Apocarchesium arndti n. sp. has several peculiarities. (i) There are ordinary zooids, macrozooids, and microzooids, which form a hemispherical rosette on a discoidal base, the stalk dish, locking the ~18 μm wide and up to 2 mm long, spirally contracting colony stalk. (ii) The stalk myoneme is connected only to the microzooids. (iii) A rosette contains up to 50 zooids not connected to each other but individually attached to the stalk dish with the scopula. (iv) The ordinary zooids are epistylidid, trumpet‐shaped (~6:1 length:width), about 180 × 30 μm in size, and have an ellipsoidal macronucleus subapically between oral cavity and dorsal side. (v) The myoneme system of the zooids, which can contract individually, forms a tube‐like structure in the narrow posterior half of the cell. (vi) The silverline pattern belongs to the transverse‐striate type. (vii) The oral apparatus is of usual structure, with kinety 1 of peniculus 3 distinctly shortened proximally. (viii) The 18S rRNA places A. arndti n. sp. as a distinct lineage near Vorticella and Carchesium. These data are used to provide an improved diagnosis of the genus Apocarchesium. Features (i)–(iii) and the molecular data indicate that Apocarchesium could be the type genus of a new peritrich family.  相似文献   

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The peritrich ciliate Epistylis portoalegrensis n. sp. was found in two bodies of freshwater located in Porto Alegre, Southern Brazil. Morphological features were investigated using live and protargol‐stained specimens. The zooids presented a vase to cylindrical shape narrowed at the scopula, and a mean size of 131 × 37 μm in vivo. A C‐shaped macronucleus lay in the middle of the cell close to a single contractile vacuole. The oral infraciliature was typical for the genus, with all infundibular polykineties composed by three distinct rows of kinetosomes. Colonies are often nonbranched with no lateral stalk, carrying several zooids stemming from a single point. Specimens from the two sampling sites showed identical arrangement of the infraciliature, similar morphometry, identical 18S rDNA sequences, and a single nucleotide difference across the more variable ITS regions. Molecular phylogenetic analyses placed E. portoalegrensis in a well‐supported clade containing other Epistylis species, within the order Vorticellida.  相似文献   

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A new genus of anascan lunulitiform bryozoan, Pseudolunularia . is introduced for two new species, P. enigma and P. unguis . It is inferred that live colonies both possess basal rhizoids and are supported and stabilized by elongate avicularian mandibles. The autozooids, brooding zooids and avicularia of both species bear a striking resemblance to a parallel pair of species belonging to the genus Lunularia, L. repandus and L. cupulus .  相似文献   

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A new tribe, genus and species of straight-snouted weevils (Dominibrentus leptus, n. gen., n. sp., Dominibrentini, n. tribe; Coleoptera: Brentidae; Cyphagoginae) has been described from Dominican amber. The new taxon is characterised by compressed, ventrolateral concavities on the prothorax and abdomen and lateral concavities on the metathorax for reception of the legs. This is the first representative of a straight-snouted weevil in amber.  相似文献   

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Scalithrium gen. n. (Cestoda, Tetraphyllidea) is proposed with Scalithrium minimum (Van Beneden, 1850) n. comb., parasite of Dasyatis pastinaca (Elasmobranchii, Dasyatidae) as type-species. The new genus Scalithrium (Tetraphyllidea, Phyllobothriidae, Rhinebothriinae) is erected for several species previously included in the genus Rhinebothrium. These species have a scolex with four bothridia, the distal surface of which is divided by transverse septa in a single row of loculi. Scalithrium minimum (Van Beneden, 1850) n. comb. is redescribed from specimens collected from the type-host Dasyatis pastinaca in Tunisia and becomes the type-species of the new genus. After Braun (1900) Echeneibothrium variabile Van Beneden, 1850 is considered as type-species of the genus Echeneibothrium. Species of Rhinebothriinae to be transferred into the genus Scalithrium are discussed and a key is proposed for the eight species.  相似文献   

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Three peritrichous ciliates, Zoothamnium arcuatum n. sp., Z. grossi n. sp., and Z. parahentscheli Sun et al., 2009, were collected from an estuary of the Taehwagang River, Korea. All these species were investigated based on live observations and silver staining, and their small subunit (SSU) rRNA gene was also sequenced. Zoothamnium arcuatum can be identified by a goblet‐shaped colony, double‐layered peristomial lip, and abstomally shortened row 3 of infundibular polykinety 3 (P3). Zoothamnium grossi is morphologically characterized by an alternately branched stalk with the lowest secondary stalk diverging from the main part of colony, asymmetrically bell‐shaped zooids, and three short, parallel ciliary rows in P3. Phylogenetic analysis revealed that the three Zoothamnium species described in this paper clustered with other members of the family Zoothamniidae, as expected.  相似文献   

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Two new marine peritrich ciliates, Epicarchesium corlissi n. sp. and Pseudovorticella jiangi n. sp., were discovered in mariculture waters on the coast of northern China near Qingdao. Their morphology, infraciliature and silverline system were investigated based on both living and silver-impregnated specimens. E. corlissi is characterized as follows: marine Epicarchesium with dichotomously branched stalk; zooids elongate, approximately 60–70×25–35 μm in vivo; peristomial collar double-folded; macronucleus J-shaped; single, small contractile vacuole ventrally positioned; more than 60 striations between peristome and aboral trochal band, 13–18 from aboral trochal band to scopula; abstomal end of row 1 of infundibular polykinety 3 terminating at same level as rows 2 and 3 of infundibular polykinety 3; rows 2 and 3 of infundibular polykinety 3 much longer than row 1 and converging adstomally with infundibular polykinety 1. The new species P. jiangi is diagnosed as follows: marine Pseudovorticella; zooid inverted bell-shaped, approximately 80×60 μm in vivo and with a broad, flat, thin peristomial collar that measures approximately 90 μm across; pellicle with transparent cortical vesicles; macronucleus J-shaped; number of silverlines between peristome and aboral trochal band 20–24, from aboral trochal band to scopula 9–11; abstomal end of row 1 of infundibular polykinety 3 diverges from the other two rows of this polykinety and ends alongside row 3 of infundibular polykinety 2.  相似文献   

9.
The morphology and infraciliature of a new hypotrichous ciliate, Euplotidium smalli n. sp., isolated from eutrophic coastal water in Korea, were observed in living cells and investigated using the protargol impregnation technique. This new ciliate bears 13-14 frontoventral cirri, 7 transverse cirri, and 5-6 dorsal kineties. Neither left marginal cirrus nor caudal cirrus is present. The new species differs from the related species, Euplotidium agitatum Noland, 1937 in the different number of frontoventral and transverse cirri and different body shape. With the exception of Euplotidium agitatum, the known species of the genus Euplotidium Noland, 1937 with the presence of left marginal cirrus are assigned to a new genus, Paraeuplotidium n. g. Diagnosis of Paraeuplotidium is: Gastrocirrhidae with funnel-shaped buccal cavity; with frontoventral and transverse cirri; left marginal cirrus present. Paraeuplotidium itoi (Ito, 1958) n. comb. is designated here the type species. Four additional species are included: Paraeuplotidium psammophilus (Vacelet, 1961) n. comb., Paraeuplotidium arenarium (Magagnini & Nobili, 1964) n. comb., Paraeuplotidium helgae (Hartwig, 1980) n. comb., and Paraeuplotidium prosaltans (Tuffrau, 1985) n. comb. An improved generic diagnosis of Euplotidium is suggested based on morphology and infraciliature characters: marine hypotrichs with a funnel-shaped buccal cavity; with frontoventral and transverse cirri; neither left marginal cirrus nor caudal cirri present.  相似文献   

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A new genus and species of the subfamily Callodistomidae is described. The new genus is named Pirupalkia queulensis n. gen., and was found in the small intestine of the fish Cilus montti. This new genus, compared with other genus of the subfamily differs principally in the distribution of the vitellaria and location of the uterus.  相似文献   

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A new soil ciliate, Pseudonotohymena antarctica n. g., n. sp., from King George Island, Antarctica, is described based on live observation, protargol impregnation, and its 18S rRNA gene. The new genus Pseudonotohymena is morphologically similar to the genus Notohymena Blatterer and Foissner 1988 in the following characteristics: 18 fronto‐ventral‐transverse cirri, a flexible body, undulating membranes, dorsomarginal kineties, and the number of cirri in the marginal rows. However, Pseudonotohymena differs from Notohymena particularly in the dorsal ciliature, that is, in possessing a nonfragmented dorsal kinety (vs. fragmented). In addition, the molecular phylogenetic relationship of the new species differs from that of Notohymena species. On the basis of the morphological features, the genetic data, and morphogenesis, we establish P. antarctica n. g., n. sp. In addition, the cyst morphology of this species is described.  相似文献   

15.
The authors describe and illustrate three different species of microphallid trematodes parasitic in the intestine of an American willet Catoptrophorus semipalmatus (Aves). Testiculoporus cedarkeyensis n. g., n. sp. has morphological characters related to Odhneria and Pseudospelotrema, along with a genital pore drawn back to the level of the sinistral testis. Two species of Odhneria (minuta Ke, 1979 and papilloprocera Ke, 1980), which appear aberrant because of the atypical posterior position of their genital pore, are transferred to the new genus. Endocotyle bushi n. sp. differs from the two other species in the genus by the disposition of the posterior uterine loops, the extension of the vitellarium, egg size and geographical distribution. The evaginated cirrus of Odhneria odhneri is described.  相似文献   

16.
Abstract

A new genus and species of heteronemertean, Praealbonemertes whangateaunienses n. gen. and n. sp., is described and illustrated. The species is characterised by inter alia a cephalic lacuna with strands of longitudinal muscle fibres, a proboscis with three muscle layers, and a well-developed muscle plate dorsal to the foregut and anterior intestine. The material was collected in New Zealand.  相似文献   

17.
A new genus and species of cestodes from the great-crested grebe Podiceps cristatus collected in the Eastern Europe is described. The genus Mircia gen. n. in addition to the type species M. shigini gen. n. includes the following species formerly being included in the genus Joyeuxilepis Spassky, 1947: M. decacantha (Fuhrmann, 1913) comb. n., M. decacanthoides (Borgarenko et Gulyaev, 1991) comb. n., M. fimbriata (Borgarenko, Spasskaja et Spassky, 1972), comb. n., and M. uralensis (Gulyaev, 1989) comb. n. Brief revision of the genus Joyeuxilepis is provide.  相似文献   

18.
Truyolsodontos estauni n. gen., n. sp. is described based on fossil teeth from the middle and upper Cenomanian of northern Spain. The species Protoscyliorhinus magnusLandemaine, 1991 is withdrawn from the genus Protoscyliorhinus and placed in this new one. For the new genus, the new family Truyolsodontidae is proposed.  相似文献   

19.
Entomological Review - A new genus, Wittinia gen. n., is proposed for Megalopygidae moths restricted to the Western Hemisphere. Two species are included: Wittinia cremor sp. n., the type species...  相似文献   

20.
Four epibiotic sessilid peritrichs, i.e., Zoothamnium wilberti n. sp., Baikalonis microdiscus n. sp., Epistylis anastatica (Linnaeus, 1767) Ehrenberg, 1830, and Rhabdostyla commensalis Möbius, 1888, were isolated from one syllid polychaete and three crustacean hosts in Qingdao, China. For each species, specimens were observed both in vivo and following silver staining. Their SSU rDNA was also sequenced for phylogenetic analyses. Zoothamnium wilberti n. sp. is characterized by the appearance of its colony, which is up to 350 μm high, and usually has fewer than 16 zooids, and the dichotomously branched stalk with transverse wrinkles, the conspicuously conical peristomial disc, and infundibular polykinety 3 comprising three isometric ciliary rows. Baikalonis microdiscus n. sp. can be recognized by its barrel-shaped zooid, small peristomial disc, smooth and short stalk, and its unusual infundibular polykinety 3 comprising a long inner row and a short outer row. Two poorly known species, i.e., Epistylis anastatica and Rhabdostyla commensalis, are redescribed and redefined. Phylogenetic analyses reveal that: (i) R. commensalis is closely related to the family Astylozoidae rather than to the morphologically similar Epistylididae; (ii) B. microdiscus n. sp. is sister to the family Scyphidiidae; (iii) E. anastatica groups with vorticellids and ophrydiids, which further supports the polyphyly of the genus Epistylis; and (iv) Z. wilberti n. sp. is nested within the Zoothamniidae, as expected.  相似文献   

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