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1.
One new kinorhynch genus and species and one new species from the genus Zelinkaderes are described from sandy sediment off Fort Pierce, Florida. The new genus and species, Tubulideres seminoli gen. et sp. nov. is characterized by the presence of the first trunk segment consisting of a closed ring, the second segment of a bent tergal plate with a midventral articulation and the following nine segments consisting of a tergal and two sternal plates. Cuspidate spines are not present, but flexible tubules are located on several segments, and in particular concentrated on the ventral side of the second segment. Middorsal spines are present on all trunk segments and are alternatingly offset to a position slightly lateral to the middorsal line. Zelinkaderes brightae nov. sp. is characterized by its spine formula in having middorsal spines on trunk segments 4, 6 and 8–11, lateroventral acicular spines on segment 2, lateral accessory cuspidate spines on segments 2 and 8, ventrolateral cuspidate spines on segments 4–6 and 9, lateroventral acicular spines present on segments 8 and 9, and midterminal, lateral terminal and lateral terminal accessory spines on segment 11. The spine formula of Z. brightae nov. sp. places it in a position in between Z. submersus and a clade consisting of Z. klepali and Z. floridensis. The new findings on Z. brightae nov. sp. have led us to propose an emended diagnosis for the genus.  相似文献   

2.
Six kinorhynchs were found in the stomachs of the Argentine red shrimp, Pleoticus mulleri (Bate, 1888) from the Argentine coast of Patagonia. Three new species are described: Condyloderes storchi n. sp., Pycnophyes argentinensis n. sp. and P. neuhausi n. sp. A fourth species, Kinorhynchus anomalus Lang, 1953 was previously known only from the coast of Chile. This is the third known record of kinorhynchs documented as a food source. Condyloderes storchi, n. sp. is the fourth new species in this genus. It is distinguished by its paradorsal cuspidate spines on segments 7 and 9, lateral accessory and ventrolateral spines on segments 3, 6, 7, 10 and 11. P. argentinensis, n. sp. has nearly equal sternal width for segments 3–11 (about 7% of the trunk length), episternal plates with three distinct areas along the anterior margin, mid-sternal plate with even margin, mid-dorsal spinose protrusions along the terminal borders of segments 11 and 12, and lateral terminal spines 176 μm long, about 21% of trunk length. P. neuhausi, n. sp.has a prominent posterior elongation of the tergal plate of segment 3, uneven lateral margins of the mid-sternal plate, a maximum sternal width at segment 3, no mid-dorsal spinose processes and mid-ventral thickenings on segments 10–12.  相似文献   

3.
Two new species belonging to the Echinoderes coulli group are described with their external morphologies and sequences of nuclear 18S rRNA and 28S rRNA genes, and mitochondrial COI gene. The first species, Echinoderes komatsui sp. n., is characterized by absence of acicular spines, and presence of lateroventral tubules on segments 5 and 8, laterodorsal tubules on segment 10, inverted triangle or wide oval shaped large sieve plates, lateral terminal accessory spines in female, and short tips of ventral pectinate fringe on segment 10. The second species, Echinoderes hwiizaa sp. n., is characterized by absence of acicular spines, and presence of lateroventral tubules on segments 5 and 7–9, midlateral tubules on segment 8, laterodorsal tubules on segment 10, large narrow oval shaped sieve plates on segment 9, and thick, short and blunt lateral terminal spines about 10–15% of trunk length. The diagnostic characters and key to species of E. coulli group are provided as well.  相似文献   

4.
A new homalorhagid genus and species, Mixtophyes abyssalis gen. et sp. nov., is described from the deep-sea of the Guinea Basin in the Atlantic Ocean. The new genus and species was collected during the R/V Meteor Diva2 M63/2 Cruise, and it is characterized by a trunk with segment 1 consisting of a tergal and a single sternal plate, without any subdivisions or differentiations, segment 2–10 of one tergal and two sternal plates and segment 11 of a tergal and a sternal plate. Lateral terminal spines are present in both sexes. As part of the study of the new taxon, the type material of Neocentrophyes intermedius and N. satyai was re-examined, and new information is provided for both species. Based on the information from Mixtophyes abyssalis gen. et sp. nov. and re-examination of the two Neocentrophyes species, emended diagnoses for Neocentrophyes and Neocentrophyidae are proposed, and an updated identification key to homalorhagid genera and species of Neocentrophyidae is provided. Mixtophyes abyssalis gen. et sp. nov. is tentatively assigned to Neocentrophyidae, but evaluation of our current hypotheses about homalorhagid evolution and phylogeny also indicated that the family most probably is paraphyletic and that revision of homalorhagid classification is required when new results from phylogenetic analyses become available.  相似文献   

5.
The kinorhynch fauna in two Arctic fjords at Spitsbergen was explored and eight species of Echinoderes were recorded, of which three are new to science and described herein. Echinoderes daenerysae sp. nov. is recognized by middorsal spines on segments 6 and 8 only, lateroventral spines on segments 6–9, laterodorsal and ventrolateral tubes on segment 2, lateroventral tubes on segment 5, lateral accessory tubes on segment 8, laterodorsal tubes on segment 9 and small laterodorsal tubes on segment 10. Echinoderes rhaegali sp. nov. has middorsal spines on segments 4, 6 and 8, lateroventral spines on segments 6–9, sublateral and ventrolateral tubes on segment 2, lateroventral tubes on segment 5, lateral accessory tubes on segment 8 and laterodorsal tubes on segment 10 in males. Echinoderes drogoni sp. nov. has middorsal spines on segments 4–8, lateroventral spines on segments 6–9, lateral accessory tubes on segment 5, glandular cell outlets type 2 in subdorsal, laterodorsal, sublateral and ventromedial positions on segments 2, in midlateral positions on segment 5, in sublateral positions on segment 8 and in subdorsal positions on segment 10; segment 11 has divided tergal plates. Moreover, types of other Arctic Echinoderes, including E. angustus, E. aquilonius, E. eximus, E. peterseni, E. svetlanae and E. tubilak, were re-examined and new information on glandular cell outlets type 2 is provided. Our results suggest that Arctic Echinoderes species have a circum-Artic distribution. Morphological analysis indicates that the occurrence of tubes may show intraspecific variation.

http://zoobank.org/urn:lsid:zoobank.org:pub:CBE29FE8-9233-4E3C-9757-FF9576B06C74  相似文献   


6.
记述了产于湘西泸溪特马豆克期锅塘组的刺尾虫类三叶虫Dichelepygelata的个体发育过程。其最显著的变化有头鞍形状和比例的改变,头鞍沟、颈沟与背沟的分离.鞍前箍(parafrontalband)的出现与消失.胸部肋区和轴部比例宽度的改变,尾部的形状和比例的变更,尾边缘的出现和肋沟深度的增加,以及后侧刺的位置逐渐前移。组成成虫期个体的前8个体节(6个胸节和前2个尾节)极有可能在分节0期(measpidDegree0)便已形成。从分节3期(meraspidDegree3)起在带后侧刺的体节与轴后区(postaxialfield)之间又发育出一个新的体节。过渡期尾部(transitorypygidium)在分节0期或分节1期发育出后侧刺.在分节4期又同时长出3对侧刺,其中最后一对侧刺与后侧刺一道形成成年期尾部的尾刺。  相似文献   

7.
P. Gopala  Menon 《Journal of Zoology》1972,167(3):371-397
The larval species Atlantocaris gigas Ortmann is shown to be conspecific with Heterocarpus ensifer A. Milne Edwards, while Procletes biangulatus Bate is the larva of Heterocarpus levicarina (Bate). Each species passes through 13–15 zoeal stages and 3–4 megalopal stages. The later zoeal stages are large, have a long toothed rostrum, a carinated carapace and dorsal abdominal spines. The carinae on the carapace are retained in the adult; the rostrum becomes shortened and the abdominal spines modified at metamorphosis. Larval characters support the retention of Heterocarpus in the Pandalidae.
New information on the distribution of both species is included.  相似文献   

8.
A new kinorhynch genus, Meristoderes gen. nov., and two new species from Spain and the Solomon Islands, respectively, are described. The new genus is distinguished from all other genera by the first segment consisting of a closed cuticular ring, and the second segment having partial tergosternal junctions, and a superficial midventral fold. This is a new cuticular configuration that may shed light into the phylogenetic relationships of echinoderid kinorhynchs. Meristoderes macracanthus gen. et sp. nov. from the Mediterranean coast of Spain is recognised by the presence of middorsal spines on segments 4, 6 and 8, ventrolateral tubules on segment 2, lateroventral tubules on segment 5, lateroventral spines on segments 6-9, lateral accessory tubules on segment 8, one pair of laterodorsal tubules on segment 10. Meristoderes galatheae sp. nov. from the Solomon Islands is recognized by having a middorsal spine on segment 4 only, ventrolateral tubules on segment 2, lateroventral tubules on segment 5, lateroventral spines on segments 6-9, lateral accessory tubules on segment 8 and subdorsal tubules on segment 10. Both species have a pattern of paraventral perforation site clusters on segments 3-9, with conspicuously long bracteate hairs from the posteriormost perforations sites on the segments 3-7 and 3-6, respectively.The new genus Meristoderes gen. nov. is included into the family Echinoderidae Bütschli, 1876 and appears closely related with the genera Cephalorhyncha Adrianov, 1999 and Echinoderes Claparède, 1863. The new information it provides is discussed to clarify the internal phylogeny of Echinoderidae. The terminology for cuticular characters in the overlapping area between consecutive segments is also standardized.  相似文献   

9.
A new record of monogeneric family Vietnamellidae (Insecta: Ephemeroptera) is established for India with Vietnamella sp. A described based on the larvae from Arunachal Pradesh, India. This species can be distinguished from other known species of this genus in the larval stage by the following combination of characters: (i) outer pair of projections in head large and stout, triangular, cone-shaped with serrated spines; (ii) posterolateral angles of abdominal terga 2–9 extended into sharp projections; (iii) caudal filaments pale yellowish brown with dense lateral setae on inner and outer margins of middle part; (iv) femora of mid- and hind-legs broader; and (v) second segment of the maxillary palpi shorter than first segment.  相似文献   

10.
Specimens of Kinorhyncha collected by RV Sonne from the continental shelf off the coast of Costa Rica and from the deep sea East of New Zealand as well as by RV Kaharoa in the Firth of Thames are identified as five new species of a new genus Fissuroderes gen. nov. which is distinguished from all other kinorhynch genera by a ring-like cuticle in the first trunk segment and a cuticle with midventral and lateral articulations resulting in two sternal plates and one tergal plate in segments 2-10. Fissuroderes higginsi sp. nov. can be distinguished from all other species of Fissuroderes by a laterodorsal spine in segment 2 and the lack of a lateroventral spine in segment 8. Fissuroderes rangi sp. nov. is recognized from all other species by the lack of a ventrolateral spine in segment 2, the lack of a lateroventral spine in segment 5, an extremely elongate spinose tergal extension of segment 11 and a prominent midventral spinose process of the sternal plates in segment 11. Fissuroderes papai sp. nov. is identified by the short spinose process of the sternal plate of segment 11. Only Fissuroderes thermoi sp. nov. possesses bilobed sternal plates in segment 11 and a short conical tergal extension. Fissuroderes novaezealandia sp. nov. differs from F. higginsi sp. nov. in the lack of a laterodorsal spine in segment 2, the lack of an accessory spine in a lateral position in segment 8, the lack of a sublateral spine in segment 10, the existence of a lateroventral spine in segment 8 and in the lack of a subdorsal type 2-gland cell outlet in segment 2. The former species differs from F. papai sp. nov. in the lack of a lateroventral spine in segment 8, the lack of longitudinal indentations in the posterior part of the trunk cuticle of each segment and in the existence of an elongate spinose tergal extension of segment 11 and of many fine hairs on the surface of the cuticle. Fissuroderes is included into the Echinoderidae which is suggested to enclose also the genera Echinoderes and Cephalorhyncha. Echinoderes nybakkeni Higgins, 1988 is now combined as Cephalorhyncha nybakkeni (Higgins, 1988) comb. nov.  相似文献   

11.
As part of a larger project examining and comparing the ontogeny of all major taxa of the Branchiopoda in a phylogenetic context, the larval development of Caenestheriella gifuensis (Ishikawa, 1895), a Japanese spinicaudatan ‘conchostracan’, is described by scanning electron microscopy. Seven different larval stages are recognised, in most cases based on significant morphological differences. They range in length from about 200 to 850 μm. Nauplius 1 has a plumb and lecithotrophic appearance with a rounded hind body and a labrum with an incipient medial spine. Limb segmentation is mostly unclear but the second antennae have more putative segments delineated than are expressed in the later stages. Feeding structures such as the mandibular coxal process and antennal coxal spine are only weakly developed. Nauplius 2 is very different from nauplius 1 and has three large spines on the labral margin and two long caudal spines. Feeding structures such as the mandibular coxal process and various spines and setae are developed, but whether feeding begins at this stage was not determined. The mandible has developed an ‘extra’ seta on endopod segment 1, absent in Nauplius 1. The segmentation of the second antenna has changed significantly due to fusions of various early segments. Nauplius 3 is like nauplius 2 in morphological detail, but larger and more elongate. Nauplius 4 has developed a pair of small anlagen of the carapace and rudiments of the first five pairs of trunk limbs, and the coxal spine of the antenna has become distally bifid. Nauplius 5 has a larger carapace anlage, externally visible enditic portions of the elongate trunk limbs, and a pair of primordial dorsal telson setae. Nauplius 6 has a larger and partly free carapace and better-developed, partly free trunk limbs with incipient enditic, endopodal, and exopodal setation. A pair of caudal spines, dorsal to the large caudal spines, has appeared. Nauplius 7 is quite similar to nauplius 6 but is larger and has slightly longer caudal and labral spines; also, the setation of the most anterior trunks limbs is better developed. The larval development is largely similar to that of other spinicaudatans. The larval mandible, which is evolutionarily conservative within the Branchiopoda, reveals a setation pattern similar to that of the Anostraca and Notostraca (two setae on mandibular endopod segment 1). Most other spinicaudatans and all examined laevicaudatans share another setal pattern (one seta on mandibular endopod segment 1), which could indicate a close relationship among these taxa. The second antenna undergoes a special development, which provides an insight into the evolution of this limb within the Branchiopoda. In nauplius 1 the basipod, endopod, and exopod are all superficially divided into a relatively high number of segments. In later nauplii some of these have fused, forming fewer but larger segments. We suggest that this ontogeny reflects the evolution of antennae in the conchostracans. Various aspects of the morphology of the antennae are discussed as possible synapormorphies for either the Diplostraca or subgroups of the Conchostraca.  相似文献   

12.
The second-instar larva of the bot fly Gasterophilus nasalis (L.) (Diptera: Gasterophilidae) is described for the first time, based on scanning electron microscope (SEM) studies. On the pseudocephalum the larva bears an antenomaxillary sensory complex formed by the antenna (coeloconic sensilla) and the maxillary palp with a set of six coeloconic sensilla and four basiconica sensilla. The oral opening is latero-posteriorly limited by small spines, and exhibits strongly ornamented maxillae and mandibles. The thoracic and abdominal segments are circled by two bands, each with two rows (except the last segment that has one row) of backwardly pointed spines, and have cuticular depressions. Trichoid and campaniform sensilla surround the larval segments. The anterior spiracular opening is a small aperture. The terminal end of the eighth abdominal segment shows a spiracular cavity, lateral tubercles, eight basiconic and two trichoid sensilla. Each spiracular plate has two slightly curved slits, each with a serrated rima. There is a probable ecdysial scar. The findings of this ultrastructural study are compared with those other of larval flies.  相似文献   

13.
14.
15.
 Lattice organs consist of five pairs of sensory organs situated on the dorsal carapace in cypris larvae of the Crustacea Cirripedia. The lattice organs in cypris larvae of Trypetesa lampas (Acrothoracica) and Peltogaster paguri (Rhizocephala) represent the two main types found in cirripedes, but only minor differences exist at the TEM level. Each lattice organ is innervated by two bipolar, primary receptor cells. The inner dendritic segment of each receptor cell carries two outer dendritic segments. The outer dendritic segments contain modified cilia with a short ciliary segment (9×2+0 structure). Two sheath cells envelop the dendrite except for the distal ends of the outer dendritic segments. This distal end enters a cavity in the carapace cuticle and reaches a terminal pore situated at the far end of the cavity. The cuticle above the cavity is modified. In both species the epicuticle is partly perforated by numerous small pores and the underlying exocuticle is much thinner and less electron dense than the regular exocuticle. Lattice organs very probably have a chemosensory function and are homologous with the sensory dorsal organ of other crustacean taxa. Accepted: 18 August 1998  相似文献   

16.
A new species of scorpion of the genus Neoscorpiops Vachon, 1980 is described from Northern Maharashtra. Neoscorpiops maharashtraensis sp. nov. is a medium-sized scorpion species ranging from 36 to 42 mm. Carapace, mesosoma and metasoma brown, legs and telson yellow; pedipalp in a shade of brown with carinae dark drown to black. Granulation on carapace coarse, with a few smooth patches; on mesosoma, which is restricted to the posterior half. Anterior margin of carapace with a moderately deep “U”-shaped emargination medially lacking elevated edges. Pectines well developed 7/7. Trichobothria on patella ventral 13–16. Pedipalp chela narrow and elongate in males, length-to-width ratio in males is 4.86–5.05.  相似文献   

17.
Despite the immense importance of the wing in the evolution and successful radiation of the insect lineages, the origin of this critical structure remains a hotly-debated mystery. Two possible tissues have been identified as an evolutionary origin of wings; the lateral expansion of the dorsal body wall (tergal edge) and structures related to an ancestral proximal leg segment (pleural tissues). Through studying wing-related tissues in the red flour beetle, Tribolium castaneum, we have previously presented evidence in support of a dual origin of insect wings, a third hypothesis proposing that wings evolved from a combination of both tergal and pleural tissues. One key finding came from the investigation of a Cephalothorax (Cx) mutant, in which the ectopic wing characteristic to this mutant was found to be formed from both tergal and pleural contributions. However, the degree of contribution of the two tissues to the wing remains elusive. Here, we took advantage of multiple Cx alleles available in Tribolium, and produced a variety of degrees and types of ectopic wing tissues in their prothoracic segments. Through detailed phenotypic scoring of the Cx phenotypes based on nine categories of mutant traits, along with comprehensive morphological analysis of the ectopic wing tissues, we found that (i) ectopic wing tissues can be formed at various locations in the prothorax, even internally, (ii) the lateral external ectopic wing tissues have tergal origin, while the internal and posterior external ectopic wing tissues appear to be of pleural origin, and (iii) the ectopic wing tissues of both tergal and pleural origin are capable of transforming into wing surface tissues. Collectively, these outcomes suggest that the evolutionary contribution of each tissue to a complete wing may be more complex than the simple binary view that is typically invoked by a dual origin model (i.e. the wing blade from the tergal contribution + musculature and articulation from the pleural contribution).  相似文献   

18.
Thirty-seven well-preserved, isolated theropod teeth from the Early Cenomanian Kem Kem beds, Morocco, are identified by using morphometric data and direct comparison with teeth previously described in the literature. Direct comparison reveals that four different morphotypes (MT 1–4) are present in the sample. The teeth of MT 1 are characterised by unserrated carinae and belong to spinosaurid dinosaurs. The teeth of MT 2–4 have serrated carinae, and our data analysis indicates they are of carcharodontosaurid, dromaeosaurid, and abelisaurid origin. Three types of crown enamel ornamentation are present among the teeth of MT 1, which implies that, apart from Spinosaurus aegyptiacus STROMER 1915, more than one species of spinosaurine theropods may be present in the Early Cenomanian of Northern Africa. Our results also confirm the occurrence of abelisaurids, dromaeosaurids, and carcharodontosaurids in Morocco.  相似文献   

19.
In this study, one of Doublesex genes from the common freshwater cladoceran Daphnia carinata, designated DapcaDsx1, was cloned using primers based on homologous sequences and rapid amplification of cDNA ends (RACE). qPCR was employed to quantify differences in DapcaDsx1 expression between the different sexual phases, with expression levels being higher in sexual females. The role of DapcaDsx1 in the reproductive transformation was further investigated in parthenogenetic-phase females and sexual-phase females using whole-mount in situ hybridization. This cellular localization study showed specific expression of DapcaDsx1 in the thoracic segments, second antenna and part of the ventral carapace. Higher expression levels were exhibited in sexual females compared to parthenogenetic females. This suggests that the DapcaDsx1 gene plays significant roles in switching modes of reproduction and during sexual differentiation.  相似文献   

20.
Two new species of Argulus Müller, 1785 (Crustacea: Branchiura) are described from Africa. A. fryeri n. sp., parasitic on an unknown fish species collected from Lake Turkana, Kenya, is characterised by: deep antero-lateral depressions which delimit a pronounced frontal region; robust, square second maxillae ornamented with numerous small, simple scales; and the shape of the respiratory areas. The most distinctive features of A. gracilis n. sp., parasitic on Auchenoglanis occidentalis var. tanganicanus collected from Lake Tanganyika, are the anterior spines on the first antennae and the shape of the respiratory areas. A. brachypeltis Fryer, previously known only from the female, is characterised by: a narrow, elongate body with foreshortened carapace lobes; small, slender terminal spines on the first antennae; and short terminal segments on the second maxillae with minute claws. The identity of the male described as A. ambloplites Wilson is discussed and renamed A. confusus nom. nov.  相似文献   

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