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1.
Polyclithrum ponticum sp. n. is described and P. mugilini Rogers, 1967 is redescribed. Both monogenean species are parasites of Mugil cephalus in the Black Sea. The new species differs from P. mugilini, P. alberti and P. boegeri by the lesser size of anchors, while it is distinguished from P. corallense by the larger size of these structures. P. ponticum sp. n. differs from all formerly described species by the greater length of dorsal connective bar. In both species from the Black Sea, "ear-like" structures situated near the external roots of anchors are described for the first time. It is suggested, that these structures take part in longitudinal, two-lobe folding of the haptor. The process of opening the haptor is probably performed by the additional bars of the haptor (bars 2 and 3 after: Rogers, 1967), joined to each other and with the anchors. The fifth pair of additional bars (Ernst e. a., 2000) derives from the "beard" of ventral connective bar and is united with its basal part. The sixth pair of additional bars (Ernst e. a., 2000) is considered as a typical "ribs" of the haptor, and therefore the "ribs" are represented by three pairs. Differences between marginal hooks of P. ponticum sp. n. and P. mugilini are insignificant, that probably depends on the presence of "ribs" of the haptor. Based on the subdivision of marginal hooks into two groups, the presence of additional supporting structure in the haptor, and the presence of the seminal receptacle, it is suggested that the subfamily Polyclithrinae Rogers, 1967 should include the genera Polyclithrum Rogers, 1967, Swingleus Rogers, 1969, Macrogyrodactylus Mamlberg, 1959, and probably Fundulotrema Hargis, 1955. Based on such characters as the lack of the anchors, the presence of suckers in the haptor, and ovipositing of eggs, it seems to be expedient to use the following taxa in systematics of gyrodactylids: Isancistrinae Fuhrmann, 1928 (genera Isancistrum, Anacanthocotyle); Gyrdicotylinae Vercammen-Grandjean, 1960 (Gyrdicotyle) and Ooegyrodactylinae Harris, 1983 (genera Phanerothecium, Ooegyrodactylus, Nothogyrodactylus, Hyperopletes).  相似文献   

2.
The delimitation of the neotropical genera of the Marantaceae has been revised, using evidence mainly from the morphology of inflorescences and flowers. It is concluded that the generic concepts of Schumann in "Das Pflanzenreich", often questioned by 20th century American authors, are essentially sound, but that his grouping of the genera into two tribes is quite artificial. Main deviations from the treatment of Schumann are the rearrangement of the genera, somewhat different stress on diagnostic characters and a much narrower concept of the genus Myrosma. A new genus, Koernickanthe is proposed for the long known species Maranta orbiculata (Koern.) Schum. The genera are arranged into informal groups and the groups and genera recognized are: Maranta group (Maranta L., Monophyllanthe Schum.), Myrosma group (Myrosma L. f., Saranthe (Regel et Koern.) Eichl., Hylaeanthe Jonker et Jonker, Ctenanthe Eichl., Stromanthe Sond.), Calathea group (Calathea G. F. W. Meyer, lschnosiphon Koern., Pleiostachya Schum.), Monotagma group (Monotagma Schum., Koernickanthe gen. nov.) and Thalia "group" (Thalia L.). It is suggested, that each group has its closest affinities with Old World genera and that this indicates that the diversification of the marantaceous stock was far–reaching already before the Old and the New World became effectively isolated. It is further suggested that the early diversification of the family took place in Africa, the flora of which, although poor in species, is morphologically very diverse. Two new combinations are made, viz. Stromanthe stromanthoides (Macbr.) Anderss. and Koernickanthe orbiculata (Koern.) Anderss.  相似文献   

3.
Three new species of monostiliferous hoplonemerteans from the Great Barrier Reef province of Australia are described and illustrated. These are, with their families indicated in parentheses, Poseidonemertes bothwellae sp. nov. (Amphiporidae), Nemertes hermaphroditicus sp. nov. (Emplectonematidae) and Pantinonemertes mooreae sp. nov. (Prosorhochmidae).  相似文献   

4.
滇东南早泥盆世无颌类   总被引:4,自引:3,他引:1  
文中记述了华南鱼类两个新属,即 Gantarostrataspis gengi gen. et sp. nov. 和 Gumuaspis rostrata gen. et sp. nov.,同时对含鱼层的时代进行了讨论.  相似文献   

5.
6.
Guloptiloides (Ephemeroptera, Baetidae), gen.n., is described to accomodate the species G. gargantua (larvae) and G. spA (female imagoes) based on specimens from the Eastern coast of Madagascar. Larvae of Guloptiloides are remarkable by the adaptation of the mouthparts to a predatory diet. It is also distinct from other genera in that adults have hindwings with 3 well-marked longitudinal veins and a single extremely developed spur on the costal margin. Affinities and ecology are discussed.  相似文献   

7.
Hyoliths are usually preserved as isolated skeletal elements consisting of conch, operculum, and helens. The occurrence of a conch associated with an operculum is ordinarily exceptional, and the co-occurrence of helens with other skeletal parts is a great rarity. The extraordinary finds of hyolithid conchs associated with opercula in situ are relatively abundant in the Cambrian and Ordovician clastic sediments of the Barrandian area in the Czech Republic. The platyclaviculate operculum with clavicles divided by longitudinal walls into channels characterizes members of the newly established family Slapylitidae fam. nov., which includes two genera: Slapylites Marek, 1980 known from the mid-Cambrian of West Gondwana and Baltica and Nevadalites Marek, 1976 documented from the Late Cambrian of Laurentia. To this family most probably belongs also an operculum from the Cambrian Series 2–Series 3 boundary of North Greenland and poorly known material from the Middle Devonian of Bolivia.  相似文献   

8.
9.
10.
Oligaphorurini represent tribe of the subfamily Onychiurinae, which currently comprises 5 genera and 53 species. The present study evaluated the monophyly of Oligaphorurini genera. We investigated phylogenetic relationships among 39 species, representing all extant genera of Oligaphorurini. Both equal- and implied-weighting parsimony analyses were used in phylogenetic reconstruction. The cladistic analyses were based on comprehensive survey of adults’ morphological characters because specimens suitable for molecular studies were not available for the majority taxa. The phylogenetic analysis resulted in the recognition of a monophyletic Chribellphorura, and strongly supported non-monophyly of the previously recognized genera Archaphorura, Dimorphaphorura, Micraphorura, and Oligaphorura. The following new synonymy is recognized: Oligaphorura = Dimorphaphorura syn. nov., = Micraphorura syn. nov., = Archaphorura syn. nov. The general classification of Oligaphorurini is followed by the diagnoses of genera and key to the all known species.  相似文献   

11.
Re-examination of 35 species and some "varieties" has led to a division of the whole " Peloscolex " complex of species into eight genera, Peloscolex Leidy, 1850, Spirosperma Eisen, 1879, Embolocephalus Randolph, 1892, Orientodrilus gen.n., Baikalodrilus gen.n., Haber gen.n., Edukemius gen.n., and Tubificoides Lastochkin, 1937. This division is based first and foremost on the construction and histology of the male genital organs, but it is also supported by other characteristics.  相似文献   

12.
Tauroprimnoa austasensis gen. nov., sp. nov. and Digitogorgia kuekenthali gen. nov., sp. nov. are described and illustrated from Southern Ocean waters. The most distinctive characters of the newly proposed genera are, in Tauroprimnoa, the existence of four marginal scales, two abaxials with a strong thorn, and the presence of a single abaxial longitudinal row of body scales. In the case of Digitogorgia, the colony branching pattern, the structure of the opercular scales, and the presence of a complete cycle of accessory opercular scales are the distinct features to distinguish it from previously known genera. Tauroprimnoa austasensis sp. nov. is reported from the Eastern Weddell Sea, Antarctica, while Digitogorgia kuekenthali sp. nov. has been found in the SubAntarctic waters off Burdwood Bank and, in the south east of Isla Nueva in Chilean Patagonia.  相似文献   

13.
The four o'clock family (Nyctaginaceae) has a number of genera with unusual morphological and ecological characters, several of which appear to have a "tendency" to evolve repeatedly in Nyctaginaceae. Despite this, the Nyctaginaceae have attracted little attention from botanists. To produce a phylogeny for the Nyctaginaceae, we sampled 51 species representing 25 genera (of 28-31) for three chloroplast loci (ndhF, rps16, rpl16, and nrITS) and included all genera from North America. Parsimony, likelihood, and Bayesian methods were used to reconstruct the phylogeny for the family. The family is neotropical in origin. A radiation of woody taxa unites Pisonia and Pisoniella with the difficult tropical genera Neea and Guapira, which also form a clade, though neither appears to be monophyletic. This group is sister to a clade containing Bougainvillea, Belemia, and Phaeoptilum. A dramatic radiation of genera occurred in the deserts of North America. The tribe Nyctagineae and its subtribes are paraphyletic, due to over-reliance on a few homoplasious characters, i.e., pollen morphology and involucre presence. Two notable characters associated with the desert radiation are cleistogamy and edaphic endemism on gypsum soils. We discuss evolutionary trends in these traits in light of available data about self-incompatibility and gypsum tolerance in Nyctaginaceae.  相似文献   

14.
Acalyphoideae, the largest subfamily of Euphorbiaceae, are investigated with respect to ovule and seed structure on the basis of 172 species of 80 genera in all 20 tribes of Acalyphoideae sensu Webster. All species of Acalyphoideae examined have bitegmic ovules with a non-vascularized inner integument. However, noticeable differences exist among and sometimes within the genera in the thickness of the inner and outer integument, the presence or absence of vascular bundles in the outer integument, whether ovules are pachychalazal or not, the presence or absence of an aril, seed coat structure (in terms of the best-developed mechanical cell-layer), and the shape of cells constituting the exotegmen. For the latter two characters, two different types of seed coat (i.e., "exotegmic" and "exotestal") and three different types of exotegmic cell (i.e., palisadal, tracheoidal and ribbon-like) were distinguished. Comparisons showed that three tribes Clutieae, Chaetocarpeae and Pereae are distinct from the other Acalyphoideae as well as from the other Euphorbiaceae in having an exotestal seed coat with a tracheoidal exotegmen. The tribe Dicoelieae is also distinct from the other Acalyphoideae in having an exotegmic seed that is composed of ribbon-like cells of exotegmen (i.e., cells both longitudinally and radially elongated, sclerotic and pitted). The tribe Galearieae, which should be treated as a distinct family Pandaceae, is also distinct from the other Acalyphoideae in having an exotegmic seed with a tracheoidal exotegmen (i.e., cells longitudinally elongated, sclerotic and pitted). The remaining genera of Acalyphoideae always have an exotegmic seed with a palisadal exotegmen (i.e., cells radially elongated, sclerotic and pitted). The shared palisadal exotegmen supports the close affinity of Acalyphoideae (excluding five tribes) with Crotonoideae and Euphorbioideae. Within the remaining genera of Acalyphoideae, a significant diversity is found in ovule and seed morphology with respect to the thickness of the inner and outer integument, the size of chalaza, vascularization of an outer integument and an aril.  相似文献   

15.
Two new genera and three new species of soft-winged flower beetles (Coleoptera, Malachiidae) are described from Rovno and Baltic Eocene amber. Protocephaloncus gen. nov. with the type species P. perkovskyi sp. nov. was found in the Rovno amber. It differs from its congeners in the tribe Troglopini in the primitive sculpture of the male facial area as a longitudinal narrow depression between the eyes lacking an appendage inside, and two trapezoid impressions on both sides of the depression closer to its lower part. A transverse pronotum, slightly rounded, but not sinuate posteriorly, is also a diagnostic feature of the new genus. A new genus of the tribe Attalini, Palpattalus gen. nov., was found in the Baltic amber. The tarsal comb on the anterior second tarsomere of the male, complicatedly curved pygidium, and cylindrical apical palpomere allow the definite attribution of the genus to the tribe Attalini. The characteristically enlarged, rounded and slightly flattened 1st palpomere, possessing a long seta directed outward, of the new genus resembles similar structures found in members of the tribe Colotini, all males of which have modified and enlarged 3rd and 4th palpomeres. Probably, Palpattalus gen. nov. represents an ancestral form for these two tribes. This allows the establishment of independent status for Antholinus Mulsant and Rey, 1867 stat. resurr., with anterior tarsi in males lacking comb on the second tarsomere, in contrast to all other subgenera of Attalus Erichson, 1840. Males of two different species, Palpattalus baltiensis sp. nov. and P. eocenicus sp. nov., were found as inclusions in Baltic amber. They differ in the coloration of the elytra, yellow with black spots in Palpattalus baltiensis sp. nov. and unicolorous black in P. eocenicus sp. nov.; the shape of pygidia, longitudinal and strongly elongated in P. baltiensis and transverse and rounded in P. eocenicus, and in a number of other characters.  相似文献   

16.
梵净山自然保护区蕨类植物区系   总被引:15,自引:2,他引:13  
邓莉兰  杨传东   《广西植物》1991,11(1):44-50
梵净山属武陵山脉主峰,位于贵州省东北部,东经108°45′55″—108°48′30″,北纬27°49′50″—28°1′30″,海拔500—2493.4米,面积约600平方公里,其蕨类植物区系组成共39科83属182种。在区系结构}二表现出下列几个一般的特征:(1)种系密度大,成分多样1(2)温带性质,是泛北极区系的一部分,与热带地区有一定的亲缘联系;(3)特有现象明显;(4)是东南亚成分(含中国一喜马拉雅和中国—日本成分)分布中心的一部分:是中国—喜马拉雅和中国一日本成分交汇中心的一部分;(5)属内种系贫乏;(6)与华东地区的关系密切。  相似文献   

17.
Arostropsis groehnigen. et sp. n. is described from Baltic amber and temporarily placed in the tribe Naupactini. It differs from all recent Naupactini genera with open corbels by very short and flattened scape, distinct lateral carina of the pronotum and elytra, and the rostrum distinctly narrower than the head capsule. The shape of head in the extinct genus is somewhat similar to that of the extant Naupactini genera with enclosed corbels (Platyomus Sahlberg, 1823 and Aptolemus Schoenherr, 1842), but differs in the slender body, open corbels, very short antennal scape and epifrons without a median sulcus (only a longitudinal depression is slightly visible). It is also similar to the Tanymecine genus Pandeleteius Schoenherr, 1834 in general appearance, but distinct by the straight anterior edge of the pronotum, lack of postocular spurs, lobes, and vibrissae, a slightly sloping elytral declivity, lateral ridges on the pronotum, subflattened antennal scape, elongate rostrum, and sparsely setose epistome. A new synonymy of the generic names Protonaupactus Zherikhin, 1971 and Sucinophyllobius Wanat & Borowiec, 1986, syn. n., is established. The Madagascan genus Corecaulus Fairmaire, 1903 is transferred from the tribe Naupactini to the Brachyderini because of its connate claws and the similarity in chaetotaxy of the epistomal area with African and Madagascar Brachyderini genera. A key to the identification of known Baltic amber genera of Entiminae is proposed. A checklist of the prepleistocene fossil Entiminae, based on V.V. Zherikhin's data, with remarks and corrections, is presented.  相似文献   

18.
Dactylogyridean monogeneans of the siluriform fishes of the Old World   总被引:4,自引:0,他引:4  
This is a catalogue and discussion of the known dactylogyridean monogenean genera of siluriform fishes of the Old World. Of a total of 38 nominal genera, only 19 are considered valid. Seventeen of these 19 genera are currently in the Ancyrocephalidae (containing the Ancyrocephalinae and Ancylodiscoidinae), whilst the other two (Neocalceostoma and Neocalceostomoides) are in the Neocalceostomatidae. The 17 genera are Anchylodiscus, Ancylodiscoides, Bagrobdella, Bifurcohaptor, Bychowskyella, Chauhanellus, Cornudiscoides, Hamatopeduncularia, Mizelleus, Paraquadriacanthus, Pseudancylodiscoides, Protoancylodiscoides, Quadriacanthus, Schilbetrema, Schilbetrematoides, Synodontella and Thaparocleidus. Clariotrema Long, 1981 and Neobychowskyella Ma, Wang & Li, 1983 are considered synonyms of Bychowskyella Akhmerov, 1952, Anacornuatus Dubey, Gupta & Agarwal, 1992 is considered a synonym of Quadriacanthus Paperna, 1961, Mizellebychowskia Gupta & Sachdeva, 1990 is considered a synonym of Neocalceostoma Tripathi, 1959 and Hargitrema Tripathi, 1959 is treated as a synonym of Hamatopeduncularia Yamaguti, 1953. It is proposed that the Ancylodiscoidinae be raised to family status within the order Dactylogyridea to accommodate these 17 `ancyrocephalid' genera from siluriforms, together with Malayanodiscoides and Notopterodiscoides from notopterids. A key and the diagnostic characteristics of the 19 recognised dactylogyridean genera from catfishes plus two from notopterids, together with a list of species and synonyms, are included. New combinations made in this work are Thaparocleidus avicularia (Chen, 1987) n. comb., T. calyciflorus (Chen, 1987) n. comb., T. choanovagina (Luo & Lang, 1981) n. comb., T. dissimilis (Chen, 1988) n. comb., T. leiocassis (Reichenbach-Klinke, 1959) n. comb., T. meticulosa (Chen, 1987) n. comb., T. parasoti (Zhao & Ma, 1999) n. comb., T. persculpus (Chen, 1987) n. comb., T. valga (Chen, 1987) n. comb. and T. wulingensis (Yao & Wang, 1997) n. comb. [all from Silurodiscoides] and Bychowskyella glyptothoraci (Ma, Wang & Li, 1983) n. comb. [from Neobychowskyella].  相似文献   

19.
Summary Cassunema exigua n.g., n.sp., Monilonema lacunosa n.g., n.sp. and Foliostoma macropodis n.g., n.sp. are described from the stomach of the redlegged pademelon, Thylogale stigmatica Gould, 1860 (Marsupialia: Macropodidae), from north Queensland, Australia. All three genera belong to the subfamily Cloacininae Stossich, 1899 and to the tribe Macropostrongylinea Lichtenfels, 1980. The genus Cassunema is characterized by a poorly sclerotized buccal capsule with longitudinal ridges formed by the lining of the anterior part of the capsule. The genus Monilonema is characterized by a leaf-crown like flange at the mouth opening, a bulbous cervical collar, and paired dorsal and ventral tubular structures running internally and posteriorly from the collar. The genus Foliostoma is characterized by a leaf crown of tiny elements at the mouth opening, and oesophagus with short narrow anterior part, wide posterior part, bulb narrower than corpus and a heavily sclerotized ring between buccal capsule and oesophagus. A revised definition of the tribe Macropostrongylinea is given together with a key to the genera. ac]19810101  相似文献   

20.
Luis Via Boada 《Geobios》1981,14(2):247-251
Preceded by a short report on the fauna associated with Decapods in the Cenomanian from Orobe and by historical references, this note is an account on the results obtained after elaborate study of 187 specimens of Anomura belonging to Galatheidae family. Those results allow the systematic delimitation of two genera: ParagalatheaPATRULIUS, 1960 and Eomunidopsis n. gen., which produce the revision of 5 species belonging to those two genera. A provisional determination of the rest of the material (14 Brachyurans), still under consideration, is proposed.  相似文献   

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