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1.
Zhou, H., Fend, S. V., Gustafson, D. L., De Wit, P. & Erséus, C. (2010). Molecular phylogeny of Nearctic species of Rhynchelmis (Annelida). —Zoologica Scripta, 39, 378–393. The Nearctic species of Rhynchelmis (Clitellata, Lumbriculidae) are known primarily from cool‐water habitats in western North America. Their taxonomy has so far been based on limited collections from isolated localities, using intuitive assessment of morphological characters. This approach has proved unsatisfactory when additional populations of closely related species were sampled and scrutinized for incorporation in the present classification. Therefore, in this study, mitochondrial (cytochrome c oxidase subunit I and 16S rDNA) and nuclear internal transcriber spacer (ITS rDNA) genes were analysed as phylogenetic markers of Nearctic Rhynchelmis species. A combined approach with all the three gene regions provided a better resolution than any of the individual genes by itself. The genes demonstrated monophyly of all major groupings proposed on the morphological basis. Within the Rhynchelmis yakimorum complex, however, the genetic data and distribution suggested that two clades initially referred to as a ‘R. yakimorum variant 1’, one from the lower Snake River drainage in Idaho and one from southern coastal Oregon, might represent two separate species. On the other hand, the sympatric distribution and low genetic distance between Rhynchelmis gustafsoni and a form tentatively identified as ‘R. cf. yakimorum’ (both collected in eastern Idaho) indicated conspecific status. This study also showed that the cytochrome c oxidase subunit I (COI) gene, which may be informative of recent and on‐going speciation and useful for species discrimination (as a DNA barcode), is less suitable as a single molecular marker for phylogenetic inference. Regardless of whether one deals with very closely related species (such as those of the yakimorum complex), with taxa with a wide and disjunct distribution (such as Rhynchelmis rostrata), or with more distantly related species, COI data should be supplemented by other genetic markers as well as morphological and biogeographical information.  相似文献   

2.
Fend  Steven V.  Gustafson  Daniel L. 《Hydrobiologia》2001,463(1-3):13-22
Secubelmis limpida n. sp., n. gen., is described from Montana, U.S.A. The monotypic genus resembles the lumbriculid genera Rhynchelmis and Tatriella in having atria in X, spermathecae in VIII, and semi-prosoporous male ducts. It differs from Tatriella in having paired atria and spermathecae, and from Rhynchelmis in having petiolate atria. The single prostate gland is unique within the Lumbriculidae. The new species appears to have a restricted range in the northern Rocky Mountains.  相似文献   

3.
4.
Wang  Xinhua  Sæther  Ole A. 《Hydrobiologia》2001,444(1-3):237-240
Rheocricotopus (Psilocricotopus) calviculus sp. n. and R. (P.) villiculus sp. n. from China are described as male imagines. The species are closely related to the previously described R. (P.) orientalis Wang forming a new group, the orientalis group, which eventually may deserve the rank of subgenus or even genus. The group is distinguished by lacking a humeral pit, numerous sensilla clavata on third palpomere, cuneiform wings, no or few setae on squama, long legs, banded abdomen, very long inferior volsella, gonocoxite with apical extensions, and gonostylus with a median triangular projection.  相似文献   

5.
Five species are described from fishes in deep waters of the northwestern Atlantic Ocean: Lepidapedon gaevskayae n. sp. from Coryphaenoides (Nematonurus) armatus; L. merretti n. sp. from Phycis chesteri; L. zubchenkoi n. sp. from Coryphaenoides (Chalinura) leptolepis; L. beveridgei n. sp. from C. (N.) armatus; and Lepidapedon sp. innom. from Antimora rostrata. The genus Lepidapedon is discussed and divided into groups of species distinguished by the vitelline distribution and the extent of excretory vesicle. The new species are placed in their appropriate groups and differentiated from the other species in the group.  相似文献   

6.
Pietro Ornodeo 《Hydrobiologia》1996,334(1-3):11-15
Kathrynella guyanae gen. n., sp. n. from a limicolous habitat in Guyana is described. It is distinguished from the known genera of Alluroididae by having testes in XI, male pores in XIV, and one pair of spermathecae opening laterally at 6/7. The circulatory apparatus appears remarkably developed. The diagnosis of the family is emended to include the new species.  相似文献   

7.
8.
Abstract

Clavaptera ornata gen. et sp. n. from leaf-litter from North Cape, Northland, New Zealand, is described and figured. This new genus falls within Group 1 of the Carventinae as proposed by Usinger & Matsuda (1959), and shares some characteristics of Carventaptera and Neocarventus, but it is readily distinguished from these genera by the medial fusion of the mesothorax and metathorax and the presence of a large hexagonal median prominence in the region of fusion. The holotype male was collected in leaf-litter near Serpentine access road, 4 miles from Spirits Bay road and the allotype from the Tapotupotu Stream area, at the base of Cape Reinga.  相似文献   

9.
Twelve species of the genus Dinaraea Thomson are recognized in the Nearctic region, ten of which occur in Canada, all east of the Rocky Mountains. Six species are herein described as new to science: Dinaraea bicornis Klimaszewski & Webster, sp. n.; Dinaraea curtipenis Klimaszewski & Webster, sp. n.; Dinaraea longipenis Klimaszewski & Webster, sp. n.; Dinaraea quadricornis Klimaszewski & Webster, sp. n.; Dinaraea worki Klimaszewski & Jacobs, sp. n.; and Dinaraea piceana Klimaszewski & Jacobs, sp. n. Four formerly described species are confirmed in Canada: Dinaraea angustula (Thomson), Dinaraea backusensis Klimaszewski & Brunke, Dinaraea borealis Lohse, and Dinaraea pacei Klimaszewki & Langor. The previously unknown male of Dinaraea borealis Lohse and female of Dinaraea backusensis are described. All species are illustrated with colour habitus images and black and white images of the median lobe of the aedeagus and spermatheca, and tergite VIII and sternite VIII of both sexes. New habitat and distribution data are presented and a key to all Nearctic species of the genus is provided.  相似文献   

10.
Abstract

Zygina medioborealis n.sp. is described from silver beet and carrots from Papua New Guinea. Indications are that this species, along with its close allies from Australia, New Zealand, and Norfolk Island, forms an incipient genus radically different from Palearctic and Nearctic Zygina Fieber. A few species of leafhopper and planthopper are listed, with their hosts; Cofana nigrilinea (Stål) is a new record for this locality.  相似文献   

11.
Six species of marine tubifieids are described from the continental shelf off Peru. Two of them are members of the gutless genus Olavius Erséus, 1984 (subfamily Phallodrilinae). Olavius bullatus sp.n. possesses 2 pairs of large penial setae in voluminous copulatory sacs, tiny atria, and spermathecal pores in line with dorsal setae. Olavius crassitunicatus sp.n. is characterized by small atria with thin muscular layer, spermathecae with short ducts, opening dorso-laterally, and lack of penial setae. Four species arc members of the subfamily Limnodriloidinae. Limnodriloides busilicus sp.n. belongs to the appendiculatus-group (sensu Erséus). It is discriminated by somatic setae with subdental ligaments, and its voluminous elongate prostatic pads. Limnodriloides clavellatus sp.n. is distinguished from its congeners by a peculiar bulge in the cavity of each atrial ampulla, and spermatozeugmata imbedded in the walls of the spermathecae. Tectidrilus intermixtus sp.n. is similar to T. bori (Righi & Kanner, 1979); it is distinguished from the latter by having trisetal bundles in segment V or V-VI and by lacking copulatory glands. Marcusaedrilus peruanus sp.n. is characterized by nongranulated atrial ducts and bipartite spermathecae.  相似文献   

12.
The definition of Marcusaedrilus Righi & Kanner, 1979, is modified to include M. hummelincki Righi & Kanner, 1979, M. luteolus sp.n. (both from the Caribbean), and six new species from the Great Barrier Reef, M. grandiculus sp.n., M. minusculus sp.n., M. tuber sp.n., M. capricornae sp.n., M. sacculatus sp.n., and M. irregularis sp.n. The genus is largely distinguished from the closely related Limnodriloides Pierantoni, 1903, by its partially ciliated atria and its tripartite spermathecae.  相似文献   

13.
The new enchytraeid species Lumbricillus healyae sp. n. is described from freshwater streams, with well-oxygenated and poorly mineralised waters, situated in Byers Peninsula (Livingston Island, South Shetland Islands, Antarctica). Lumbricillus healyae sp. n. is morphologically close to L. antarcticus and L. incisus, and it is mainly distinguished by the structure of the spermatheca with a short, distinct ectal duct, the oval penial bulb (greatest diameter in the transverse body axis) associated with strong dorso-ventral muscular fibres, and a protrusible pseudopenis. A second undetermined Lumbricillus species is described from a small stream. Study specimens are not fully mature; however, the highly irregular form and size of the testis-sac lobes and the absence of a penial bulb encapsulated under a muscular layer are remarkable. It is probably related to a small group of Lumbricillus species reported from the Antarctic maritime region (L. colpites, L. griseus and L. aestum), characterised by the structure of the male duct, which ends in a simple pore surrounded by glands.
Eugenio RicoEmail:
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14.
Parafabricia ventricingulata females have a pair of spermathecae located in the radiolar crown anterio-dorsal to the buccal opening. The spermathecae have three regions; an entrance, 7 μm across, leading into a ciliated ‘atrium’ that is approximately 50 μm long; a connecting piece, 2–5 μm across and 25 μm long, leading from the ‘atrium’ to the sperm receptacle. The sperm receptacle is heavily pigmented and spherical. The sperm lie in a large mass in the receptacle with no particular orientation. Oriopsis bicoloris females have a pair of unpigmented spermathecae in the collar behind the radiolar crown. Each spermatheca is a simple blind duct 100 μm long, with a lumen 8 μm in diameter. Between 30 and 40 sperm lie in the lumen of each spermatheca. Oriopsis brevicollaris females have a pair of spermathecae located in the radiolar crown above the buccal opening. From the opening, 10 μm across, a blind duct runs for 90 μm. Sperm are stored in the distal region of the duct. Sperm lie along the margins of the duct in close contact with microvilli. Up to 10 sperm were found in each spermatheca. Oriopsis mobilis females have a pair of spermathecae located in the radiolar crown above the buccal opening. The opening, 3 μm across, leads into a blind duct that runs for 30 μm. Sperm are stored in the distal region of the spermathecae where they are embedded in spermathecal cells. Between 10 and 20 sperm were found in each spermatheca. Oriopsis dentata was found not to have spermathecae. The homologies of the spermathecae found within the Sabellinae and Fabriciinae (Sabellidae) and the Spirorbinae (Serpulidae) are discussed, but cannot be resolved on present evidence.  相似文献   

15.
Rhynchospora pseudomacrostachya (Cyperaceae) is restricted to the southern Brazil states of Rio Grande do Sul and Santa Catarina. Previously, material ofR. pseudomacrostachya had been thought to belong toR. corniculata var.macrostachya (Torr. ex A. Gray) Britton (R. macrostachya Torr. ex A. Gray) of North America. However,R. pseudomacrostachya can be distinguished from the North American taxon on the basis of achene and inflorescence characters.  相似文献   

16.
A second species of the genus Sciaphyes Jeannel is reported from Japan. The new species, S. kawaharai sp. n., can be easily distinguished from other Japanese Cholevine by the lack of eyes and hind wings. S. kawaharai sp. n. was collected in the nests of lesser white-toothed Shrew, Crocidura suaveolens (Pallas 1811) (Insectivora: Soricidae), therefore its habitat is pholeophile.  相似文献   

17.
Miroslav Barták 《Biologia》2006,61(5):503-508
Rhamphomyia (Lundstroemiella) cervi sp. n. (France), R. (L.) cimrmani sp. n. (Turkey) and R. (L.) speighti sp. n. (France) are described and illustrated. A key to the Palaearctic species of the subgenus Lundstroemiella Frey is given.  相似文献   

18.
Summary

In many simultaneously hermaphroditic land snail species, the sperm storage organ (spermatheca) is highly structured, suggesting that the female function might be able to influence offspring paternity. Physical properties of the sperm storage organ, including its initial size and sperm storage capacity, may also affect fertilization patterns in multiply mated snails. We examined the structure, volume and tubule length of empty spermathecae in the land snail, Arianta arbustorum, and assessed differences in spermatheca size following a single copulation. The number of spermathecal tubules ranged from 2–7, but was not correlated with the volume of empty spermathecae. The volume of sperm stored in the spermatheca after a copulation was correlated with neither the number of spermathecal tubules nor copulation duration. Mean spermathecal volume more than doubled between two and thirty-six hours after sperm uptake, but the length of the spermathecal tubules did not change. Interestingly, the volume of sperm stored in the spermatheca seems not to be related to the size of the spermatophore and thus not to the number of sperm received (= allosperm). The amount of allosperm digested in the bursa copulatrix was highly variable and no significant relationship with the size of the spermatophore received was found. These findings suggest that numerical aspects of sperm transfer are less important in influencing fertilization success of sperm in A. arbustorum than properties of the female reproductive tract of the sperm receiver.  相似文献   

19.
Two new species of chironomid midges (Rheosmittia arcuata n.sp. and Mesocricotopus loticus n.sp.) are recognized. They may easily be missed in collections due to their small size, and difficulty in collecting from the larval microhabitat (sand substrates for R. arcuata n.sp., low order streams with depositional substrates including gravel, sand, and silt for M. loticus n.sp.). Some morphological features are given to distinguish the new species from similar congeneric forms. The distribution and some ecological information for each species are also briefly discussed.  相似文献   

20.
Tectidrilus probus sp.n. and Tectidrilus profusus sp.n. are described from offshore localities in southern California. Both species appear closely related to T. diversus Ersëus, 1982, which occurs in the same area, but they differ from the latter by possessing small oesophageal diverticula; T. probus differs also by its very small spermathecal vestibules. Tectidrilus profusus is a highly apomorphic form with elaborate, partly muscular, male ducts and spermathecae. Monophyly of Tectidrilus is supported by the short clitellum and the unisetal 'bundles' in postclitellar segments. Patterns of apomorphic character states within the genus are analyzed under the principle of Camin-Sokal parsimony (irreversibility of character states), giving three equally parsimonious cladograms. In the strict consensus tree of these cladograms, eight of the twelve members of Tectidrilus form an apomorphic group defined by the papillated body wall, but the individual species within this group cannot be unequivocally resolved from each other.  相似文献   

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