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1.
Troglocyclops janstocki is proposed to accommodate cyclopids from Hatchet Bay Cave, Eleuthera Island, Bahamas. The species is the most primitive member of the Halicyclopinae because of the presence of 15-segmented antennules, mandibular palp reduced to 3 setae, one of them quite long and plumose, a bisegmented maxillary endopodite, and 3 segments in the maxilliped endopodite. These copepods possess the first pediger still distinct, being partially enclosed dorsally and laterally by a carapace-like extension of the posterior margin of the dorsal cephalic shield. This latter character represents a plesiomorphic state shared with the primitive cyclopinids and, within the Cyclopidae, only with the Euryteinae. The new taxon is the only known species of Halicyclopinae having two apical spines on the terminal segment of the exopodite of legs 2 to 4, and the intercoxal sclerites of the legs 1 and 2 sexually dimorphic. The phylogenetic importance of each of these characters is discussed.  相似文献   

2.
A new copepod genus and species, Speleohvarella gamulini, collectedfrom the anchialine cave iva Voda on Hvar Island (Croatia),is described from both sexes. This is the first record of acalanoid copepod found in an Adriatic anchialine cave. The newgenus is distinguished from other Stephidae by a combinationof the following features: the cephalosome is separate fromthe first pedigerous somite, and the fourth and fifth pedigeroussomites are fused; the female urosome has 4 segments, the genitaldouble-somite is symmetrical and the caudal rami is asymmetricalwith the right longer than the left; antennules of both sexesare symmetrical and 24-segmented, with the fusion of ancestralsegments II–IV, X–XI and XXVII–XXVIII; theexopod of antenna is 7-segmented; 2 setae are present on thebasal exite of maxillule; in the male the right leg 5 is shortand 3-segmented, and the left leg elongate and 5-segmented.  相似文献   

3.
A new genus and species of calanoid copepod belonging to the family of Ridgewayiidae is described from an anchialine cave on the small island of Badija, Croatia. In the new species Badijella jalzici, body length varies from 720-870 µm in both sexes. The prosome is 6-segmented, the female urosome is 4-segmented and 5-segmented in the male. The antennules are symmetrical and 26-segmented in the female, and 23-segmented on right side in the male, with two areas of geniculation. The caudal rami are symmetrical and longer than wide. The mouthparts and swimming legs 1-4 are identical in both sexes. The female fifth leg is biramous and symmetrical; the male fifth legs are strongly developed, asymmetrical, biramous on both sides, endopods 2-segmented and exopods 2-segmented and complex in structure.  相似文献   

4.
5.
Recent diving explorations of anchialine caves on the Turks and Caicos Islands yielded a rather small and slender new species of Remipedia. Micropacter yagerae n. gen., n. sp. is distinguished from all other species of nectiopod remipedes by a number of autapomorphic characters, including an oval body terminus with fused segments, unequal pairs of terminal claws on maxilla and maxilliped, an almost complete reduction of sternal bars and pleurotergites, molar processes with relatively few, but strong spines, and frontal filaments with bifurcate processes. Based on the unique combination of derived and primitive characters, we propose to erect a new family, Micropacteridae, for this new species and genus of Remipedia. Taxonomic diagnoses for the class Remipedia, order Nectiopoda (emended due to discovery that the maxilliped is 9-segmented), and for the families Speleonectidae and Godzilliidae are presented and discussed.  相似文献   

6.
A new species of poecilostomatoid copepod, Erebonaster spinulosus (Erebonasteridae), is described on the basis of a single female from a depth of 3 266 m at cold seeps near the base of the West Florida Escarpment in the eastern Gulf of Mexico. Among its distinctive features are: the large body highly ornamented with setules and spinules, the rostrum with small median teeth and lateral setules, the claw of the second maxilla with a prominent knob on the concave margin, the maxilliped ornamented with setules and its claw bearing a digitiform process near the seta, the third segment of the exopod of leg 4 with the formula II,I,4, and the highly ornamented leg 5 having on the free segment a very long seta 9 times the length of the segment.The genus Erebonaster now contains two species, the previously described Erebonaster protentipes found in 2000 m at the Guaymas Basin, Gulf of California, and the new Erebonaster spinulosus.  相似文献   

7.
The life cycle of Ergasilus briani is shown to consist of six nauplius stages, five copepodid stages and the adults. Only the adult female is parasitic. The free-living stages are described in detail. The presence of three aesthetascs on the antennules of all copepodid stages and the adult is noted for the first time. Unusual aspects of E. briani development include: the antennule is sexually dimorphic from copepodid IV onwards, the dimorphism being expressed in the numbers of setae present on the more proximal segments, and the first appearance of the male maxilliped is at the copepodid II stage. The endopodal setation of the male maxilliped is the maximum known within the Poecilostomatoida. The striking pigmentation of the developmental stages of ergasilids is noted and discussed.  相似文献   

8.
A new species of poecilostomatoid copepod, Doridicola indistinctus n. sp. (Rhynchomolgidae), is described from specimens found in association with the soft coral Gersemia fruticosa Sars (Alcyonacea: Nephtheidae), collected from the White Sea. The new species is distinguished from its congeners by the combination of the following features in the female: (i) antenna tipped, with two subequal large claws which are about as long as the segment bearing them; (ii) two naked, extremely unequal setae on the middle segment of the maxilliped, the short, medial seta less than half-length of the outer seta; and (iii) free segment of leg 5 bears the basal swelling and is ornamented with spinules on the outer surface. This is the first report of a copepod occurring in symbiosis with nephtheid corals from the Arctic Zone. It also constitutes the northernmost record for a species of Doridicola Leydig, 1853, which is the largest genus of the Rhynchomolgidae Burmeister, 1835 comprising 52 species, including the present new species.  相似文献   

9.
10.
In Riptortus clavatus (Thunberg) (Heteroptera : Alydidae), growth and development of cuticular structures were compared between normal antennae and the antennae whose distal (4th) segment had been amputated during the 1st instar. The total length of the remaining 3 segments was 51% of the normal antenna. From the 2nd ecdysis onwards, the 2nd and 3rd segments grew excessively, and after adult emergence, the length of the operated antennae was 84% that of a normal antenna, although a typical 4th segment, separated from the 3rd segment by an intersegmental membrane, never developed. On the new distal (3rd) segment of operated antennae, long fine sensory hairs and grooved pegs, which characterize the normal distal (4th) segment, began to appear at the 2nd ecdysis, and successively increased in number between molts. Thus, when the distal segment was removed, the remaining segments tended to gradually compensate for the loss, both in terms of length and cuticular structures.  相似文献   

11.
我们在整理西北地区收集的淡水鱼寄生桡足类标本时,发现鳋科(Ergasilidac)的二个新种,现记述于下。模式标本保存于中国科学院昆明动物研究所。  相似文献   

12.
A new species of the Notodelphyidae belonging to Paranotodelphys Schellenberg, 1922 is described from both sexes. The new species, Paranotodelphys illgi, can be distinguished from its congeners by the combination of its 10-segmented female antennule, the bisetose fifth legs and the extreme elongation of the caudal rami of the female, which are more than 10 times longer than wide and 4.4 times longer than the anal somite. The male has non-geniculate antennules. The new species was collected at a depth of 508m in the North Pacific Ocean, from the ascidian Corynascidia herdmani Ritter.  相似文献   

13.
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   

14.
Specimens of a deep-living sabellid polychaete of the genus Perkinsiana Knight-Jones dredged in Antarctic waters were found to be parasitised by an undescribed species of the cyclopoid copepod genus Sabellacheres M. Sars, 1862. Specimens of both sexes were studied using light microscopy and SEM, and compared with its congeners. The new species, Sabellacheres antarcticus n. sp., can be distinguished from its congeners by the shape and proportions of the body and brood-pouch, its 4-segmented antennae, the shape and length of the distal process of the second antennular segment, the position of leg 3, and the structure of the male maxilliped. This is only the second record of a species of this genus from the southern hemisphere. The new species was found on a single host species, as is typical for most species of Sabellacheres. A key for the identification of both sexes of the species of Sabellacheres is included.  相似文献   

15.
Procyclopina polyarthra Herbst is redescribed and three new species, P. maricopeba, P. feiticeira and P. uguaipuku , are described from intertidal interstitial waters. Procyclopina is distinguished within the family by the enditic setation of the maxilliped 0,1,3,4, the 19-segmented antennule, and three elements in the leg 5 exopod of the female. Procyclopina has its distribution restricted to the coast of Säo Paulo, Brazil. Procyclopina maricopeba sp. n. is distinguished from P. polyarthra by the three-segmented leg 5 in the male and by the length: width ratio of the genital double somite in the female. Procyclopina feiticeira sp. n. is unique in the genus by lacking the inner seta on legs 14 exp-I, and by the incomplete fusion of genital (seventh thoracic) and first abdominal somites in the female. Procyclopina uguaipuku sp. n. is characterized by the antennulary armature, by the caudal ramus (much longer than wide), and by the position of the proximal seta of the leg 4 enp-2 which is set on a protuberance on the posterior face. Morphological characters of Procyclopina are compared with those of other cyclopinids.  相似文献   

16.
Isocyamus kogiae n. sp. is described from a pygmy sperm whale Kogia breviceps (De Blainville, 1838) stranded on Moreton Island, Queensland, Australia. It belongs in the genus Isocyamus because of its white appearance, epaulette-like processes at the anterior dorsum of pereon segment 2, lateral spines on segments 3 and 4, reduced maxilliped, and absence of maxilliped palps, large accessory gills and dentate comb on the dactyle of gnathopod 1. It differs from Isocyamus delphini (Guerin-Meneville, 1836), the only other member of this genus, in that the accessory gills are not equal in length to the main gills, it has no ventral spines, and the dactylus of percopod 1 has a double rather than a single dentate comb. This is the first report of a cyamid from whales of the genus Kogia.  相似文献   

17.

A new parasitic copepod, Tiddergasilus bipartitus n. sp. (Copepoda, Ergasilidae), is described herein based on three adult females found attached to the gills of the yellow-tail lambari Astyanax lacustris (Lütken), sampled in Pardo River, municipality of Botucatu, São Paulo State, Brazil. Tiddergasilus bipartitus n. sp. was recognized as a new member of the monotypic genus Tiddergasilus Marques & Boeger, 2018 by having: antennule 6-segmented; maxillary basis armed with 2 terminal teeth and ornamented with multiple spinules; second and third leg both with endopod 3-segmented. The new copepod can be distinguished from its congener, Tiddergasilus iheringi (Tidd, 1942), by the morphology of the antennal claw, number of somites/segments in abdomen and fourth leg, and by the ornamentation of the first leg. This report expands the geographic distribution and diversity of fish species parasitized with Tiddergasilus spp. in Brazil. Moreover, it also represents the first report of an ergasilid species in the Pardo River. A list of diagnostic features for the Brazilian species of Ergasilus von Nordmann, 1832 is provided herein, in order to aid comparisons with the species of this complex genus.

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18.
Postembryonic development in the kinorhynch species Antygomonas incomitata was examined using scanning electron microscopy. The morphology of the six juvenile stages, J‐1 to J‐6, varies at numerous details, but they can also be distinguished by a few key characters. Juvenile stage 1 by its composition of only nine trunk segments; J‐2 by the combination of possessing 10 trunk segments, but no cuspidate spines on segment 9; J‐3 by the presence of cuspidate spines on segment 9, but only one pair of cuspidate spines on segment 8; J‐4 by the combination of 10 trunk segments only, but having two pairs of cuspidate spines on segment 8; J‐5 by possessing 11 trunk segments and same spine compositions as adults but is still maintaining postmarginal spiculae; J‐6 specimens closely resemble adults and are most easily identified by their reduced trunk lengths. New segments are formed in a growth zone in the anterior part of the terminal segment. The complete number of segments is reached in J‐5. Development of cuticular head and trunk structures are described through all postembryonic stages and following developmental patterns could be outlined: the mouth cone possesses outer oral styles from J‐1, but in J‐1 to J‐3, the styles alternate in size. Scalids of the introvert are added after each molt, and scalids appear earliest in the anterior rings, whereas scalids in more posterior rings are added in older postembryonic stages. The early J‐1 stage is poor in spines and sensory spots and both structures increase in number after each molt. The complete spine composition is reached in J‐4, whereas new sensory spots appear after all molts, inclusive the final one from J‐6 to adult. Sensory spots in the paraventral positions often appear as Type 3 sensory spots but are through development transformed to Type 2. This transformation happens earliest on the anterior segments. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

19.
A new genus and new species of mantidflies, Doratomantispa burmanica n. gen., n. sp. (Neuroptera: Mantispidae), is described from Burmese amber. Diagnostic characters of the new genus are small body size, trichosors present around entire wing margin except basally, protarsus 5-segmented with paired, simple claws but no aroleum, profemur bearing six cuticular spines, inner surface of protibia with row of peg-like protrusions, Sc meets R1 in region of pterostigma, costal space greatly narrows toward wing apex, with 16 veinlets in costal space on front wing while costal veinlets on hind wing are replaced by trichosors and CuP absent in hind wing. The abdomen of the mantidfly is filled with large spheres resulting from a possible rickettsial infection. Phoretic heterostigmatid mites are adjacent to the wings of the fossil.  相似文献   

20.
Summary The antennal-tip sensory complex inAllacma fusca (Collembola) was reconstructed from serial ultrathin sections. The complex contains 16 sensory cells which belong to three spatially separated subunits: (1) a sensory hair; (2) a cuticular protrusion, containing two highly-specialized dendritic outer segments from a single sensory cell encapsulated by an enveloping cell and a gland cell (Figs. 4 and 5); and (3) two sensory cells with partly lamellated, double dendritic outer segments located well away from the cuticular surface (Fig. 3). A phylogenetic evaluation reveals a mosaic of apparently primitive characters, and trends toward higher structural complexity as well as toward reduction (Table 1). There is support for a hypothesis that the receptors of the sensory hair are chemosensitive. The functional interpretation of the other components of the complex is problematic due to their unusual structural properties. The sensory cell beneath the cuticular protrusion is considered to be proprioceptive.Supported by the Deutsche Forschungsgemeinschaft (Al 56/6)  相似文献   

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