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1.
During the Spanish oceanographic expedition BENTART '95, carried out in Antarctic waters off Livingston Island (South Shetland Islands), five small specimens of a new species of Solenogastres-Cavibelonia, Dorymenia troncosoi sp. nov., were collected at a depth of 65–240 m on a silt bottom. The species is characterized by the presence of a pallial cavity with four pouches (a dorsal, two lateral and a ventral pouch), seminal receptacles that open into the spawning ducts through a short duct, radula having 9–11 teeth per row (1 central and 4–5 lateral, all the same size), the end of the copulatory spicules having a cross-section in the shape of a four-pointed star, and abdominal spicules present. These characteristics separate this species from other species of the genus, particularly from Dorymenia profunda, which is the most similar. Received: 9 April 1998 / Accepted: 12 June 1998  相似文献   

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Three new species of Rubus subgenus Rubus series Pallidi from Spain are described, mapped and illustrated: R. Cyclops, R. castroviejoi and R. urbionicus.  相似文献   

4.
Ch. Todt 《Zoomorphology》2006,125(3):119-134
Foregut glands in Solenogastres are not only of importance in biological processes like feeding and digestion, but multicellular foregut glands also provide valuable characters for taxonomy and systematics. Here, the fine structure of four different types of foregut glands is investigated: the Meioherpia-type ventrolateral foregut gland of Meioherpia atlantica, the Simrothiella-type ventrolateral foregut gland of Simrothiella cf. margaritacea, and the Pararrhopalia-type ventrolateral foregut gland as well as the dorsal gland of Pararrhopalia pruvoti. Thereby, special focus is set on the arrangement of glandular and supporting cells within the glands, and on the characterization of glandular cells according to the size, shape and electron-density of their secretional vesicles. It is shown that the investigated glands are complex organs composed of non-glandular supporting cells and two to five glandular cell types producing discrete secretions.  相似文献   

5.
Tritoniid sea slugs (Mollusca, Gastropoda, Opisthobranchia) are reported for the first time from Bouvet Island. Tritonia dantarti sp. n. shows morphological and anatomical differences with regard to the two previously known tritoniids reported from Antarctica and Sub-Antarctica, Tritonia vorax (Odhner 1926) and Tritonia challengeriana Bergh, 1884. Regarding the external morphology, T. dantarti sp. n. is characterized by a very bright orange coloration in the dorsum, white dorsal crests, highly ramified dendritic gills (the largest vertically orientated and the rest laterally orientated), and a quadrangular cross section. The radula presents very long, thin lateral teeth and the jaws present mainly unicuspidate, striated denticles. The seminal receptacle is large, pear-shaped and its grey pigmentation differs from the rest of the genital system. The Antarctic species T. challengeriana was also found in waters off Bouvet Island, while the Subantarctic species T. vorax was not found.  相似文献   

6.
Recently collected specimens of Armodoris from McMurdo Sound, Antarctica, were morphologically examined and sequenced. Comparison between this new material and literature sources revealed that it belongs to an undescribed species, Armodoris anudeorum. Although this new species is externally very similar to Armodoris antarctica (the only previously known species of Armodoris), these two species differ in several details of their external morphology, and particularly in their reproductive anatomy and radular morphology. This is the second known species of Armodoris; thus, this paper doubles the known diversity of this exclusively Antarctic group.  相似文献   

7.
Abstract. The ultrastructure of the ciliary apparatus of multiciliated epidermal cells of the trochophore of Epimenia babai and the adult of Strophomenia scandens was studied. The trochal cirri of E. babai consists of long cilia with unspecialized tips. The surfaces between the trochs are sparsely covered with shorter cilia of similar structure except for length. In the adult of S. scandens , the foot is covered by a dense mat of cilia with blunt electron-dense tips. In both E. babai and S. scandens , all cilia have two perpendicularly orientated rootlets. This condition is similar to that of the Chaetodermomorpha (=Caudofoveata) and Polyplacophora. In other molluscs studied to date, the cilia of multiciliated epidermal cells have a single rootlet or a derivative thereof. The presence of two ciliary rootlets likely represents the basal plesiomorphic state for the Bilateria. The existence of this character in the Neomeniomorpha, Chaetodermomorpha, and Polyplacophora is congruent with the hypothesis of a basal position of these taxa within the Mollusca.  相似文献   

8.
Three new species of dicyemid mesozoan are described from Octopus sasakii Taki, 1942, collected from Tosa Bay and Kii Strait in Japan. Dicyema shimantoense n. sp. is a medium-size species that reaches about 3,000 microm in length, and lives in folds of the renal appendages. The vermiform stages are characterized by having 22 peripheral cells, a conical calotte, and an axial cell that extends to the base of the propolar cells. Infusoriform embryos consist of 37 cells; a single nucleus is present in each urn cell, and the refringent bodies are solid. Dicyema codonocephalum n. sp. is also a medium-size species that reaches about 2,000 microm in length. It too lives in folds of the renal appendages. The vermiform stages are characterized by having 17-22 peripheral cells, an elongated calotte, and an axial cell that extends to the middle of propolar cells. Infusoriform embryos consist of 37 cells; a single nucleus is present in each urn cell, and the refringent bodies are solid. Dicyemennea pileum n. sp. is a medium species that reaches about 2,000 microm in length. It attaches to the surface of the renal appendages. The vermiform stages are characterized by having 23 peripheral cells, a disc-shaped calotte, and an axial cell that extends to the propolar cells. An anterior abortive axial cell is absent in vermiform embryos. Infusoriform embryos consist of 38 cells; 2 nuclei are present in each urn cell, and the refringent bodies are liquid. These are the first dicyemids to be described from Octopus sasakii.  相似文献   

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This paper contributes to the knowledge of the pingue group of species within the genus Diphascon. Three new species are described, Diphascon (D.) polare, D. (D.) dastychi and D. (D.) victoriae, from Victoria Land (Antarctica); they differ from other species of the pingue group in characters of the bucco-pharyngeal apparatus. D. polare and D. victoriae differ also in the claw shape. A key is provided to the Diphascon pingue group. Accepted: 30 November 1998  相似文献   

10.
Sphaeralcyon shackletonisp. nov. and Sphaeralcyon scottisp. nov. are described and illustrated from material collected at the Scotia Sea and Weddell Sea on the Polarstern cruises ANT XIX/3 (ANDEEP-I), ANT XIX/5 (LAMPOS), and ANT XXI/2 (BENDEX). With the discovery of Sphaeralcyon shackletoni and S. scotti, three species are now known in the genus Sphaeralcyon, all them reported from the Southern Ocean. The diagnosis of the genus has been slightly modified to accommodate some of the characters of the new species.  相似文献   

11.
A new species, Anaphalis himachalensis (Asteraceae) is described from the Lahaul-Spiti district of Himachal Pradesh in North-West Himalayas.  相似文献   

12.
A new species of Valantia , V. lainzii Devesa & Ortega-Olivencia, endemic to the coastal zone of Granada (southern Spain) is described. The species recalls V. muralis L. in its general aspect, and V. deltoidea Brullo in the type of fructiferous body.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 331–335.  相似文献   

13.
We describe here two new species of oegopsid squids. The first is an Asperoteuthis (Chiroteuthidae), and it is based on 18 specimens. This new species has sucker dentition and a funnel–mantle locking apparatus that are unique within the genus. The second new species is a Promachoteuthis (Promachoteuthidae), and is based on a unique specimen. This new species has tentacle ornamentation which is unique within the genus. We also describe a new genus and a new species of sepioid squid in the subfamily Heteroteuthinae (Sepiolidae) and it is based on four specimens. This new genus and species exhibits unique modifications of the arms in males.  相似文献   

14.
Two new species are described, viz. Clavija repanda from Ecuador (prov. Loja) and C. minor from Colombia (dept. Santander). Floral biology and the subdioecious nature of the two species are briefly discussed.  相似文献   

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During the examination of a large suite of tropical deep-water molluscs, a number of Solenogastres were found, some of them typically curled around gorgonian stems. A subsequent closer examination of the Solenogastres revealed another type of object also curled around the gorgonians, which strongly resembled Solenogastres but lacked their external features. These objects proved to be cocoons with egg capsules, each containing two eggs or young larvae, typical of the parasitic platyhelminth group Fecampiida.  相似文献   

17.
Spirobrachia orkneyensis sp. nov. is described from the Orkney Trench to the east of the South Orkney Islands from a depth of 6130–6420 m. It differs from the congeneric species S. grandis (Ivanov 1952) and S. leospira (Gureeva 1975) in the structure of the tube, i.e. shorter segmental collars, peculiarities of their arrangement throughout the tube, and multi-layered, light-coloured tube wall with wrinkles in its inner layers. Also, the wings of the spermatophores of the new species are much larger than those of the two other species of the genus, while most other size characteristics, including the length of the spermatophores, the size of the cuticular plaques, the number of the tentacles and the diameter of the tube, are intermediate between those of S. grandis and S. leospira. A key to the genera and species of the family Spirobrachiidae is provided. Accepted: 31 January 2000  相似文献   

18.
Diplococcium dimorphosporum sp. nov., D. racemosum sp. nov., D. singulare sp. nov. and D. pulneyense Subram. & Sekar collected from plant debris in natural areas of Spain are described and illustrated. The first species is characterized principally by the production of branched conidiophores and short chains of conidia. Diplococcium singulare has unbranched conidiophores, and conidia produced usually at the tip of conidiophores and from lateral spherical conidiogenous cells. In addition, both species develop a Selenosporella synanamorph with narrow falcate conidia. Diplococcium racemosum produces branched, verrucose conidiophores, and verrucose conidia in long branched chains. Diplococcium pulneyense is the second record, being described for first time on the natural substratum and re-described in pure culture. A key to currently accepted species of Diplococcium is provided.  相似文献   

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Background  

The 18S rRNA gene is one of the most important molecular markers, used in diverse applications such as molecular phylogenetic analyses and biodiversity screening. The Mollusca is the second largest phylum within the animal kingdom and mollusks show an outstanding high diversity in body plans and ecological adaptations. Although an enormous amount of 18S data is available for higher mollusks, data on some early branching lineages are still limited. Despite of some partial success in obtaining these data from Solenogastres, by some regarded to be the most "basal" mollusks, this taxon still remained problematic due to contamination with food organisms and general amplification difficulties.  相似文献   

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