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1.
U. Mühlenhardt-Siegel 《Helgoland Marine Research》1994,48(1):79-88
Six specimens ofLeucon parasiphonatus n. sp. were collected at depths ranging from 15 to 424 m in the vicinity of King George Island (South Shetland Islands, Antarctica)
and the south eastern Weddell Sea.Leucon parasiphonatus belongs to the subgenusLeucon and differs from the other already known antarctic and Subantarctic species of the genus, in the absence of a serrated dorsomedian
line and in the presence of a long pseudorostrum with several fine setae at its tip, surrounding the very long branchial siphon.
The surface of the carapace is granulated; the carapace displays no teeth except for a few at its antero-lateral margin and
at its ventral margin. The species most similar toLeucon parasiphonatus isLeucon siphonatus, reported from Mediterranean and North Atlantic waters. 相似文献
2.
A new species of Cumacea belonging to the genus Lamprops Sars was collected from the East Sea of Korea. This new species resembles Lamprops
comatus Zimmer, Lamprops
carinatus Hart, Lamprops
flavus Harada, Lamprops
pumilio Zimmer, Lamprops
tomalesi Gladfelter, and Lamprops
obfuscatus (Gladfelter) in lacking lateral oblique ridges on the carapace and lateral setae on the telson. The new species, however, is distinguished from its congeners by having a dorsal concave groove and a lateral rounded depressed area on pereonite 2. The new species is fully illustrated and compared with related species. A key to the world Lamprops species lacking lateral ridges on the carapace is also provided. 相似文献
3.
J. D. D. BISHOP 《Zoological Journal of the Linnean Society》1982,74(4):345-357
Three new, and apparently closely related, species of cumacean are described from the continental slope off Surinam: Leucon turgidulus sp.nov. from about 500 m depth, L. medius sp.nov. from about 1000m and about 1500m, and L.jonesi sp.nov from about 1500m and about 2000m. The species have not been found in extensive collections from other parts of the deep Atlantic. Leucon pallidus G.O. Sars, 1865 is the most closely comparable of the previously known members of the genus. 相似文献
4.
Cumaceans are a diverse order of small, benthic marine crustaceans. Phylogenetic hypotheses for the eight currently recognized cumacean families have not been formally proposed. However, based on external morphological traits and Linnean classification, a few conflicting hypotheses of relatedness have been proposed. Family definitions rely on morphological characters that often overlap and diagnoses are based on a combination of non-unique characters. Morphological analysis does not provide a well-resolved phylogeny. In the present study, we use amino acid sequences from the mitochondrial cytochrome oxidase I gene to produce a molecular phylogenetic hypothesis for the families of Cumacea. Phylogenetic analyses at the amino acid level were performed under Bayesian, likelihood, and parsimony methods. Results strongly suggest that families lacking an articulated telson form a monophyletic group. This pleotelson clade, composed of the families Bodotriidae, Leuconidae, and Nannastacidae, is the most derived within the Cumacea. Within this group, the Bodotriidae resolve paraphyletically, with Leuconidae and Nannastacidae embedded within it. Comparison of the molecular phylogeny with that based on morphology suggests that many "diagnostic" characters are homoplasious. 相似文献
5.
JORDI CORBERA 《Zoological Journal of the Linnean Society》2008,152(2):227-254
Cumaceans (Crustacea: Peracarida) belonging to the family Bodotriidae collected between 206 and 3680 m depth, during the French campaigns BIOCAL and BIOGEOCAL in waters of New Caledonia, KARUBAR in Indonesia and BORDAU 1 around Fiji were studied. The 93 specimens belonging to this family were assigned to 11 species, ten of them new to science, namely Cyclaspis variosculpta sp. nov., Cyclaspis richeri sp. nov., Cyclaspis dictyota sp. nov., Cyclaspis decora sp. nov., Cyclaspis magna sp. nov., Cyclaspoides erugatus sp. nov., Alticuma? ectyphum sp. nov., Apocuma pacificum sp. nov., Hypocuma fragosum sp. nov. and Bathycuma coremium sp. nov. The genera Cyclaspoides and Hypocuma are recorded for the first time from the Pacific Ocean. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 227–254. 相似文献
6.
7.
A new species of Ampelisca (Crustacea, Amphipoda) is described from samples collected in shallow subtidal fine and very fine sand in the inlet of Baiona (Galicia, NW Iberian Peninsula). Ampelisca troncosoi sp. nov. is closely related to A. brachyceras and A. heterodactyla by having a rostrum between antenna 1 pair and one lateral angle at each side of the head. The new species may be distinguished by the following combination of characters: a distally rounded rostrum between the antenna 1 pair, one laterodorsal pair of corneal lenses, antenna 1 longer than antenna 2 peduncle, antenna 2 never reaching half of the body length, epimeral plates with rounded posterodistal angle, a prominent rounded urosomal carina and two rows of minute spines on the outer rami of the uropod 3. 相似文献
8.
Systematics of the genera of Bodotriidae (Crustacea: Cumacea) 总被引:1,自引:1,他引:0
PILAR A. HAYE 《Zoological Journal of the Linnean Society》2007,151(1):1-58
The cumacean family Bodotriidae includes 382 species in 31 genera grouped in three subfamilies: Bodotriinae, Mancocumatinae and Vaunthompsoniinae. Generic diagnoses are based on few characters that often have overlapping states among genera, complicating the understanding of the relationships within the group. The goals of this study are to illuminate the phylogenetic relationships among the genera of the Bodotriidae using morphological characters and to review the systematics of the family. For this purpose, all species within each genus were studied from the literature to code all the variability of genera for 109 variable morphological characters. Phylogenetic analyses show that there is independent reduction of the pleopods in two clades from a plesiomorphic state of five pairs, while the number of exopods of peraeopods has been reduced gradually in more derived groups of bodotriids. The subfamily Bodotriinae is the most derived and the Vaunthompsoniinae the most basal, and is paraphyletic with the Mancocumatinae embedded within it. No discriminatory characters were found between the subfamilies Mancocumatinae and Vaunthompsoniinae and they are not clearly separated in the phylogeny. Mancocumatinae is synonymized with Vaunthompsoniinae and all the genera of the former Mancocumatinae should be included within Vaunthompsoniinae. Analyses of character evolution justify a few other taxonomic changes. All genera were redescribed based on all the coded characters and a complete list of all valid species for each genus is included. Finally, dichotomous keys for identification to genus level are provided. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 1–58. 相似文献
9.
Gerald A. Cole 《Hydrobiologia》1981,76(1-2):27-32
A new species of the Amphipoda (Gammarus desperatus) is described from North Spring in Roswell, Chaves County, New Mexico. Apparently this is the same species reported erroneously as G. fasciatus Say from nearby Lander Springbrook by Noel (1954).Supported in part by NSF Grants GB-2461 and GB-6477X to W. L. MinckleySupported in part by NSF Grants GB-2461 and GB-6477X to W. L. Minckley 相似文献
10.
-A new species of anisogammarid amphipod, Jesogammarus (Jesogammarus) mikadoi sp. nov., is described from freshwater habitats in northern Honshu, Japan. The species is distinguished from its congeners by having dorsal setae on pereonites 5-7 and pleonites 1-3. 相似文献
11.
Two new anisogammarid species belonging to the genus Jesogammarus were obtained from freshwater habitats from northern Japan. They are Jesogammarus (J.) fujinoi sp. nov. and Jesogammarus (J.) shonaiensis sp. nov. The former new species is diagnosed by the pleonites without spine and the telson without distolateral spine. The other new species differs from the congeneric species in having many dorsal spines on pleonites 1-3. 相似文献
12.
ANA ORTEGA-OLIVENCIA JUAN A. DEVESA 《Botanical journal of the Linnean Society. Linnean Society of London》2003,143(2):177-187
Two new species of the genus Galium are described from the Iberian Peninsula: G. moralesianum Ortega-Olivencia & Devesa, and G. talaveranum Ortega-Olivencia & Devesa. The first grows on limestone or dolomitic-limestone outcrops in south-east Spain (the Segura and Gádor mountain ranges) and shows morphological similarities with G. boissieranum Ehrend. & Krendl, which is endemic to southern Spain (mountains of Málaga). The second inhabits the margins of water courses, alder stands and cork-oak dehesas (parkland-type systems) of the west of the Iberian Peninsula, and is morphologically reminiscent of G. mollugo L. The chromosome numbers of these two species and of G. boissieranum are given. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 177−187. 相似文献
13.
A new species of apseudomorph tanaidacean, Apseudopsis adami sp. nov., is described, including intraspecific variation, from specimens collected in the seagrass meadows of O Grove inlet (NW Iberian Peninsula, NE Atlantic). The new species is characterized by the unique combination of the following characters: pointed rostrum with rounded shoulders, four ventral propodal spines on pereopod 1, and posterolateral pointed apophyses on pereonites 2–5, regardless of the developmental stage of the individual. Two juvenile stages were identified before reaching maturity; early juvenile limbs are scarcely ornamented in comparison to the adults. Advanced juveniles represent the vast majority of the studied population, and the limb ornamentation is similar to that of the adults. Males show two different cheliped morphologies. After a preparatory stage, females pass through a sequence of copulatory instars followed by intermediate stages in which the female loses the ovisac after manca release. The number of segments of the antennular and antennal flagella and uropod endopods, as well as the development and ornamentation of the mandibular palp, are meristic changes that occur during development and allow rapid identification of the developmental instar. 相似文献
14.
Catalina T. de Ward Pastor 《Hydrobiologia》1995,310(3):177-187
The major cyanobacteria in Crawford Lake are benthic mat forming Lyngbya and Oscillatoria and not phytoplankton. The eutrophication of the lake has resulted in a decline in the mat forming cyanobacteria as inferred from palaeopigment analyses of the core from this lake. In previous palaeolimnological studies the concentrations of oxillaxanthin and myxoxanthophyll have been used as correlates with lake trophic levels. High concentration of oscillaxanthin and myxoxanthophyll were interpreted as indicating eutrophic conditions prevailed. Our results indicated that when Crawford Lake was most eutrophic little oscillaxanthin and myxoxanthophyll was produced. High values of 13C at the depth of 34–48 cm (1500–1760 A. D.) were related to a dense population of benthic Oscillatoria and Lyngbya living on the bottom of the lake during that period. The Oscillatoria and Lyngbya utilize bicarbonate as a source of inorganic carbon. Carbonate has a high 13C value. Very low 13C values were found at 0–7 cm (1955–1992 A. D.) in the Crawford sediment core at the time when phyto- plankton dominated the core. Phytoplankton are enriched in 12C by photosynthetic assimilation of CO2. 相似文献
15.
A new species of Ingolfiellid Amphipod Ingolfiella azorensis n. sp. is described from samples collected in a benthic survey off the Azores archipelago, Portugal. The new species is characterized by the lack of ocular lobes, a four-toothed dactylus on the first and second gnathopods, and having dissimilar claws on the third to seventh pereiopods. Individuals were obtained from shallow subtidal samples of sand. The new findings bring the number of Ingolfiellidae from Macaronesia up to six, equalling almost 20 % of the world’s known species, suggesting this area as a potential evolutionary centre for Ingolfiellidae. 相似文献
16.
Gastrosaccus madagascariensis sp.nov. is common in thesurfzone of sandy beaches along the east and south coasts ofMadagascar. Morphologically, it is characterised by having sevenlateral spines along each side of the telson; with spines 2–4 andthe penultimate spine being dorso-lateral in origin. One or twospinules are interspersed between the fifth and terminal spines.The fourth exopod segment of pleopod 3 in the male is bulbous, bearing twoterminal barbed unequal spines. A robust and naked seta is alsopresent on the same segment in the male. 相似文献
17.
Four species of mysids collected from the Minicoy lagoon are reported. Anisomysis minicoyensis sp. nov. is distinguished from the related species by the shape of the rostrum, the relative length of the antennal scale and the short protuberances on the second segment of the mandibular palp. The other three species recorded are Siriella australiensis, Anisomysis truncata and unidentified species of subfamily Gastrosaccinae. 相似文献
18.
This is the first study of caprellid amphipods from the coast of Papua New Guinea. Several collections from Madang Lagoon
(north) and Bootless Bay (south) have been studied. Seven species in seven genera are recorded, of which Pseudoproto papua sp. nov. is described as new to science. The genus Pseudoproto Mayer, 1903 has consisted, so far, of only one species, Pseudoproto fallax Mayer, 1903. Although only a single male has been found of Pseudoproto papua sp. nov., differences in antennae, mouthparts, gnathopod 2 and pereopods 3 and 4 have revealed that it represents a new species
of Pseudoproto. Lateral view figures of all species, together with a key to species level for the Caprellidea from Papua New Guinea are
also included.
Communicated by H.-D. Franke 相似文献
19.
Doxomysis algoaensis sp.nov. is described from Algoa Bay, South Africa where it is common in nearshore marine waters just beyond the breaker line. D. algoaensis sp.nov. is morphologically similar to D. australiensis, but can readily be distinguished by the shape and armature of the telson and the length of the exopod of the fourth male pleopod. The apical cleft is one fifth the telson length in the former species and one third the length in D. australiensis. The telson apex on each side of the cleft is also armed with five and four stout spines in the two species, respectively. In D. australiensis, the exopod of the fourth male pleopod is almost three times the length of the endopod; in D. algoaensis sp.nov., the exopod is only slightly longer than the endopod. Other distinctive features of D. algoaensis sp.nov. include the maxillary palp, which is only slightly broader than long and the greater number of spines on the endopod of the uropod. 相似文献
20.
Wolfgang Dohle 《Zoomorphology》1976,84(3):235-277
Zusammenfassung Die Differenzierung der hinter den Mandibeln gebildeten ektodermalen Querreihen des Keimstreifs vonDiastylis wird beschrieben. 4 dieser Querreihen von Zellen werden nicht durch Ektoteloblasten gebildet, sondern lagern sich direkt als Blastodermzellen aneinander. Dahinter werden 12 Reihen durch Ektoteloblasten gebildet. Die Ektoteloblasten teilen sich zum Schlu\ in die Reihen XIII und XIV. Alle Zellreihen treten in eine Folge von differentiellen Teilungen ein, so da\ die genaue Differenzierung und Musterbildung der Zellen bis zur Bildung von Ganglienanlagen und ExtremitÄtenknospen zellgenealogisch verfolgt werden kann. Die ersten 2 Reihen hinter den Mandibeln, die Reihen (0) und (1), tragen zur Bildung des vorderen und mittleren Teils des 1. Maxillensegments bei. Der hintere Teil des 1. Maxillensegments wird durch die vorderen Zellabkömmlinge der Reihe (2) gebildet. Die 1. Maxille ist aus Zellen von verschiedenen Zellklonen zusammengesetzt, die zur Reihe (1) und (2) gehören. Die 2. Maxille und die Thorakalbeine werden ebenfalls durch verschiedene Zellklone zusammengesetzt.Die Reihen (2) und (3) haben ein Ähnliches Differenzierungsmuster. Die Unterschiede betreffen hauptsÄchlich den extremitÄtenbildenden Bereich. Die Reihe (3) und die erste ektoteloblastisch gebildete Reihe I sowie die folgenden extremitÄtenbildenden Reihen sind in ihrer Differenzierung fast identisch. Die Ganglien bilden sich durch Neuroblasten, welche Ganglienmutterzellen ins Innere abgeben. Die Neuroblasten haben ein kompliziertes Teilungsmuster. Sie können sich auch nach Abgabe von Ganglienmutterzellen Äqual teilen. Die Intersegmentalfurchen laufen schrÄg durch die Abkömmlinge einer Reihe und markieren nicht die genealogischen Grenzen.Die Ergebnisse werden im Vergleich mit anderen Mandibulaten, besonders mit den Insekten diskutiert. Es ergeben sich interessante Ähnlichkeiten und Unterschiede in der Bildung eines morphologischen Differenzierungszentrums und in der Anlage von ExtremitÄtenknospen, von Ganglien und Intersegmentalfurchen.
Formation and differentiation of the post-naupliar germ bandm Diastylis rathkei (crustacea, cumacea)II. Differentiation and pattern formation of the ectoderm
Summary The differentiation of ectodermal cell rows arranged on the germ band ofDiastylis behind the presumptive mandibular segment is described. 4 of the cell rows are not budded off from ectoteloblasts, but are formed directly by blastoderm cells. Behind these 4 rows, 12 cell rows are budded off from ectoteloblasts. Eventually, the ectoteloblasts divide to form rows XIII and XIV. All of these cell rows have a fixed sequence of mitoses by which a detailed analysis of the cell-lineage up to the formation of ganglion anlagen and appendage buds is possible. The rows (0) and (1) form the anterior and middle parts of the maxillular segment. The posterior part of this segment is formed by derivatives of the subsequent cell row (2). Thus, the maxillulae are complex structures, composed by cells from different cell clones. The maxillae and the thoracic limbs are complex structures as well. Rows (2) and (3) have a similar differentiation pattern. The differences are mainly found in the appendage-forming parts. The differentiation of row (3) is nearly identical to row I, i.e. the first row budded off from ectoteloblasts, and to the subsequent rows II–VI.Ganglion cells are formed by the division of ganglion mother cells that are budded off from neuroblasts. The neuroblasts have a complicated pattern of divisions. There may be an alternation of unequal and equal mitoses. The intersegmental furrows run in a transverse and slightly oblique plane through the derivatives of one cell row. They do not indicate genealogical boundaries.The results are compared with similar developmental processes in other Mandibulata, especially Insecta. The similarities and differences in the existence of a morphological differentiation center and in the formation of appendage buds, ganglion anlagen, and intersegmental furrows are discussed.相似文献