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1.
A nearly complete skeleton, including most of the thoracic member bones of the sloth Mylodon darwinii, have been found in Upper Pleistocene strata from Anisacate River, Argentina. The thoracic member bones resemble their homologues in Glossotherium robustum, Paramylodon harlani, and Mylodonopsis ibseni in the following traits: (1) the olecranon is mediolaterally compressed; (2) the radius has an acute styloid process; (3) the radial diaphysis medial border is straight for two thirds of its length; (4) the radial shaft medial border forms an angle with the medial border of the styloid process. The radius presents a distinctive, mostly proximally facing articular circumference. The unfused epiphyses and feeble muscle attachment ridges indicate a sub-adult ontogenetic stage. Deviation of the olecranon and weak M. teres major origin and insertion, suggest a low fossorial specialization. The structure of the thoracic limb bones does not support climbing habits, because pronation-related features are reduced and the humeral head is not prominent. The structure of the radius suggests graviportal adaptations: the proximal head is mediolaterally expanded and the diaphysis straight. A phylogenetic analysis adding thoracic member characters recovers M. darwinii as part of a clade that includes Glossotherium robustum and Paramylodon harlani, but excludes Lestodon armatus. This contrasts with the results of previous analyses focusing on the head skeleton, highlighting the relevance of sampling postcranial characters in phylogenetic analyses of mylodontine sloths.  相似文献   

2.
The osteology of Florenciella lugubris is described. F. lugubris is attributed to the family Epigonidae on the basis of specific characters of structure of orbital bones, skull, jaws and hyoid, presence of three principal spines on operculum, contact of pterygiophores of dorsal fins, 10 + 15 vertebrae, extension of the lateral line onto the caudal fin, structure of the first hemapophysis and interhaemale, caudal skeleton, etc. At the same time, Florenciella is more advanced in comparison with Epigonus having such characters as presence of enlarged, directed to sides and/or forward symphyseal teeth in jaws, of finely and densely denticulatd edges of infraorbitalia 2–8 and of the orbiral edge of frontale, and fontanelle in bulla otica and having specific traits of denticulation of opercular bones, having no separated distal element in the free pterygiophore between the first and second dorsal fins, having modified scales, etc. The related genera Florenciella and Rosenblattia may be synonyms.  相似文献   

3.
4.
The muscles of the male genitalia were studied for the first time in two species endemic to the Oriental zoogeographical region, namely Curetis bulis from the subfamily Curetinae (Lycaenidae) and Paralaxita damajanti from the tribe Abisarini (Riodinidae). Both taxa possess a common plan of musculature reflected in the positions of muscles m1, m2(10), m5(7), m7(6), m21, and m28. Two new autapomorphies of Curetis bulis were discovered: the splitting of m4 into two muscles and a shift of the attachment site of one of these muscles onto the dorsal area of the anellus. Apomorphic differences in the position of the genital muscles were found between Paralaxita damajanti and the previously studied Polycaena tamerlana from the family Riodinidae. A new synapomorphy between the latter two species, namely splitting of the aedeagus protractors m6(5), was also found.  相似文献   

5.
Disperis tomaszii (Orchidaceae, Orchidoideae) from Cameroon is described and illustrated in this study. The new species is morphologically similar to Disperis nitida and Disperis thomensis. Phylogenetic analyses of selected DNA regions (ITS, matK) indicate a possible relationship between the new species and Disperis anthoceros and Disperis dicerochila. The taxonomic affinity between D. tomaszii and the aforementioned species is discussed.  相似文献   

6.
The subgenus Pocusogetus Rtt. of the genus Otiorhynchus Germ. is revised. The subgenus includes O. rosti Strl., O. shapovalovi Davidian et Yunakov, O. obsulcatus Strl., O. fischtensis Rtt., and O. gusakovi sp. n. closely related to O. fischtensis (both from Mt. Fisht, the Western Caucasus). O. fischtensis is transferred from the subgenus Vicoranius Rtt., its lectotype is designated. A key to species of Pocusogetus is given. The systematic position of the subgenera Pocusogetus and Vicoranius in the genus Otiorhynchus is discussed. New data on the geographical distribution and ecology of the little-known species of the subgenera Obvoderus Rtt., Pseudoprovadilus Magnano, and Clypeorhynchus Yunakov et Arzanov are given. Some features of ecological differentiation between Otiorhynchus species in the alpine and subalpine zones of the Caucasus are discussed.  相似文献   

7.
A total of ten taxa belonging to the class Ostracoda of the Crustacea (Darwinula stevensoni, Candona neglecta, Cypria ophthalmica, Ilyocypris bradyi, Prionocypris zenkeri, Herpetocypris chevreuxi, Psychrodromus olivaceus, Heterocypris incongruens, Scottia pseudobrowniana, Eucypris sp.) were collected from two rheocrene Darwinula stevensoni springs (Çetin Bey and Çaygökp?nar springs) on 15 separate occasions between November 2002 and November 2004. Almost all of the species identified exhibit cosmopolitan distributions – at least in the Holarctic region. The presence of Scottia pseudobrowniana represents the second recording of this species in the ostracod fauna of Turkey. The dominant taxa in both springs was Cy. ophthalmica, I. bradyi, Pr. zenkeri and Ca. neglecta. Correlation analyses suggested a significant positive relationship in relative abundance between I. bradyi, Pr. zenkeri and Cy. ophthalmica. Species composition differed significantly between the upper and lower study sites for each spring, but differences could not be detected between sites at the same elevation across sites. Environmental tolerance index (ETI) values suggest that species with high optima and tolerance ranges show cosmopolitan characteristics.  相似文献   

8.
9.
The absence of significant distinctions between the species of the genus Planorbarius in the narrow sense (P. corneus, P. banaticus, P. purpura, and P. grandis) has been established. All investigated species had identical chromosomal formulas (2n = 30m + 6sm = 36) and fundamental numbers (FN = 72). Reproducible distinctions between them were not found by total complement length (TCL), relative length of chromosomes (RL), and centromeric indexes. The species selected on the basis of genetic marking differed clearly by centromeric index of chromosome 12, which confirms the allospecies frame of P.corneus s. lato.  相似文献   

10.
Species attributed to Scoliocystis Jaekel, 1899, including the type species S. pumila (Eichwald, 1860) and S. thersites Jaekel, 1899 from the Ordovician of the Leningrad Region, are reviewed. Scoliocystis sp. from the Upper Ordovician of Estonia, figured by Hecker (1964), is redescribed as Maennilocystis heckeri gen. et sp. nov. and it is attributed to the family Callocystitidae Bernard, 1895. The genus Scoliocystis is intermediate between the families Cheirocrinidae and Echinoencrinitidae in having five periproct border plates (as in cheirocrinids), but lacking plate R5 and having a reduced oral area, as in echinoencrinitids, but is retained in the Echinoencrinitidae. The similarity of Scoliocystis to the unusual North American cheirocrinid genus Sprinkleocystis is convergent. The genus Gonocrinites Eichwald, 1840, with two species, is restored among echinoencrinitids, as having four periproct border plates, whereas Echinoencrinites sensu stricto has three. The families Echinoencrinitidae and Callocystitidae arose from cheirocrinids with closed plate circlets by the loss of plate R5 and substitution of radial:lateral for radial:radial pectinirhombs. In addition, echinoencrinitids are characterized by a reduced oral area, whereas in callocystitids, the recumbent ambulacra are extensive. Scoliocystis is a stem-group genus to Echinoencrinitidae plus Callocystitidae. Several glyptocystitoid genera independently developed advanced pectinirhombs.  相似文献   

11.
Three species currently addressed to Protohydnum (Auriculariales) are studied with morphological and DNA methods. The genus Protohydnum is retained for the type species only, P. cartilagineum, recently re-collected in Brazil. The European species, P. piceicola, is not congeneric with P. cartilagineum and, therefore, placed in its own genus, Hyalodon, gen. nov. Another Hyalodon species, H. antui, is described from East Asia. The third member of Protohydnum sensu lato, P. sclerodontium from South-East Asia, is transferred to Elmerina.  相似文献   

12.
Endelus (Kubaniellus) indicus sp. n. from India, E. (K.) lao sp. n. and E. (K.) khnzoriani sp. n. from Laos, E. (s. str.) sausai sp. n. from China, and E. (s. str.) dembickyi sp. n. from India are described, the two latter species are included in the Endelus bicarinatus Théry, 1932 species-group recently established by the author. E. collinus Obenberger, 1922 is included in this group; lectotype of this species is designated. Keys to species of the subgenus Kubaniellus and of the E. collinus group are provided. E. (K.) kareni Kalashian is for the first time recorded for Shaanxi Prov., E. pacholatkoi Kalashian, E. smaragdinus Desc. et Vill., and E collinus Obenb., for Laos (the latter species, also for Myanmar).  相似文献   

13.
The faunal composition of Diptera (Insecta) inhabiting the galleries of Polygraphus proximus over the territory of Siberia and the Russian Far East was studied. As a result, 14 species of Diptera were discovered representing 8 families. Within its secondary range, the invasive beetle P. proximus Blandford, 1894 is affected not only by the well-known introduced species Medetera penicillata Negrobov, 1970 but also by numerous other widespread predatory flies, such as Medetera excellens Frey, 1909, M. pinicola Kowarz, 1877, Xylophagus cinctus (De Geer, 1776), and Toxoneura ephippium (Zettersted, 1860). Four predatory fly species, M. penicillata, M. signaticornis Loew, 1857, Lonchaea bukowskii Czerny, 1934, and Xylophagus sachalinensis (Pleske, 1925), affect P. proximus within its native range in the Russian Far East. Data on the predation of each species of Diptera on several species of bark beetles testify to their polyphagy. Saprophagous larvae of Dicranomyia modesta (Meigen, 1818), Chalcosyrphus piger (Fabricius, 1794), Xylosciara lignicola (Winnertz, 1867), and Pseudolycoriella unispina (Mohrig et Krivosheina, 1983) were discovered in bark beetle galleries for the first time.  相似文献   

14.
Examination of three species of batfishes (Teleostei: Epphippidae) from off Lizard and Heron Islands on the Great Barrier Reef led to the discovery of specimens of the trematode genus Paradiscogaster Yamaguti, 1934 (Digenea: Faustulidae). Morphological analysis demonstrated that the new specimens represented four morphotypes which we interpret to be new species: Paradiscogaster martini n. sp., P. vichovae n. sp. and P. brayi n. sp. from Platax orbicularis (Forsskål) and P. pinnatus (Linnaeus) off Lizard Island, and P. nitschkei n. sp. from P. teira (Forsskål) off Heron Island. Published material was re-examined and the specimens identified as P. chaetodontis okinawensis Yamaguti, 1971 from P. pinnatus from Okinawa, Japan, actually represent the new species P. brayi n. sp., demonstrating that some species of Paradiscogaster have wide geographical distributions. ITS2 rDNA data for the four morphotypes differ by 4–39 base pairs confirming the delineation of the four species proposed. A feature of this study is the recognition of Platax spp. as an important host group for Paradiscogaster, with the new species placing them as the second richest host group for these parasites after the Chaetodontidae.  相似文献   

15.
A complex of the heteropteran genera centering around Peribalus Mulsant et Rey and Holcostethus Fieber is considered. The genus Dryadocoris Kirkaldy reveals no relationship with the above genera and is believed to represent a separate clade of the family Pentatomidae. The genera Peribalus and Holcostethus are revised. The former includes three subgenera: Peribalus s. str. with two species, Asioperibalus subgen. n. (type species Cimex inclusus Dohrn) with six species, and Tianocoris subgen. n. (type species Holcostethus manifestus Kiritshenko) with two species. Holcostethus embraces two subgenera: Holcostethus s. str. and the monotypic Enigmocoris subgen. n. (type species H. fissiceps Horváth). Two new species are described: Peribalus tianshanicus sp. n. from the Tien Shan Mts. and P. przewalskii sp. n. from the northern part of China (Huan He River). P. capitatus Jakovlev and P. vernalis (Wolff) are downgraded to subspecies of P. strictus (F.). P. ovatus Jakovlev is synonymized with P. inclusus (Dohrn). Two new monotypic genera related to the revised complex of genera are established, Paraholcostethus gen. n. (type species Peribalus breviceps Horváth) and Himalayastethus gen. n. (type species H. pilosus sp. n. from Kashmir). A key to, and morphometric characters for all the taxa considered are provided. The key characters, including both male and female genitalia, are illustrated, and distributional maps are given.  相似文献   

16.
The genus name Euripersia Borchs. is considered a junior synonym of Fonscolombia Licht. based on the absence of essential differences between type species of these genera. The key to Fonscolombia includes, in addition to the type species, nine species from Russia and adjacent countries. Eight of these species are redescribed and illustrated, F. butorinae Danzig et Gavrilov, 2005 has been recently described as new. Two species originally described in Euripersia do not belong to this genus. One is transferred to Trionymus Berg, and thus a new combination is established: Trionymus mongolicus (Danzig), comb. n. Synonymy of Euripersia caulicola with Phenacoccus incertus Kir. has been established recently (Danzig, 2005). Other species presently placed in Euripersia (Ben-Dov, 1994) need a revision. Lectotypes are designated for 4 nominal species. Fonscolombia is related to Phenacoccus Sign., the separation of these two genera is not clear. Fonscolombia is characterized by broad-oval and convex body, poorly developed anal lobes, short, 6-8-segmented (F. edentata and F. herbacea with 7–9-segmented) antennae, and cerarii present on the last abdominal segments only (C 3 sometimes present). Most species live on roots of grasses (F. butorinae between leaves near soil, F. herbacea, on dicotyledonous herbs) and are characterized by ovoviviparity.  相似文献   

17.
Karyotypic features as well as larval and imaginal morphology have been studied in five species of the black fly genus Wilhelmia, viz. W. equina (Linnaeus, 1758), W. pseudequina (Seguy, 1921), W. lineata (Meigen, 1804), W. veltistshevi (Rubzov, 1940), and W. salopiensis (Edwards, 1927). Photomaps of polytene chromosomes are given for all species (those for W. pseudequina and W. veltistshevi, for the first time). Species-specific karyological and morphological characters have been revealed. According to principal karyological features, the species examined are divided into the equina and salopiensis groups. The validity of the species rank is confirmed for all species. Clear karyological and morphological distinctions between W. salopiensis and W. lineata give evidence that synonymization of W. salopiensis with W. lineata was erroneous.  相似文献   

18.
Sequencing of the fragment of control region in mitochondrial DNA in sculpin Cottus volki and the comparison of obtained data with homologous nucleotide sequences in the other species from genus Cottus demonstrated that C. volki occupies the basal position in the “poecilopus” group, which includes also typical sculpin C. poecilopus Heckel, 1837 from water bodies of Europe, sculpin C. szanaga Dybowski, 1869 from the Amur River basin, and sculpin Cottus cf. poecilopus from the Lena River basin. Early separation of C. volki line from common trunk of “poecilopus” group explains the presence in C. volki of several primitive (plesiomorphic for this group) morphological characters: long interior ray of ventral fin, practically complete lateral body line, and well-developed dentition of palatine bones.  相似文献   

19.
20.
The Thinodromus lunatus species group is revised. The following new species are described: Thinodromus (s. str.) cattiensis sp. n. from Vietnam, Thinodromus (s. str.) forsteri sp. n. from southern Thailand, Thinodromus (s. str.) himalayensis sp. n. from Nepal and northern India, Thinodromus (s. str.) inconspicuus sp. n. from southern China, Thailand, and Vietnam, and Thinodromus (s. str.) spotus sp. n. from southern China. The following new synonymy is established: Thinodromus (s. str.) deceptor (Sharp, 1889) = Thinodromus (s. str.) gravelyi (Bernhauer, 1926), syn. n.; = Thinodromus (s. str.) reitterianus (Bernhauer, 1938), syn. n. Lectotypes are designated for Trogophloeus lunatus Motschulsky, 1857, Trogophloeus pustulatus Bernhauer, 1904, Trogophloeus socius Bernhauer, 1904, Trogophloeus sumatrensis Bernhauer, 1915, Trogophloeus lewisi Cameron, 1919, Trogophloeus gravelyi Bernhauer, 1926, Trogophloeus reitterianus Bernhauer, 1938, and Trogophloeus unipustulatus Cameron, 1941. A key is presented to all the species of the Thinodromus lunatus group.  相似文献   

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