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1.
A revision of species of the pannote Holarctic and Oriental mayfly family Neoephemeridae is presented. Three genera are recognized in a strictly phylogenetic classification. Potamanthellus [=Neoephemeropsis Ulmer syn. n.] includes P. caenoides (Ulmer) comb. n., P. amabilis (Eaton) [=N. cuaraoensis Dang syn. n.], P. ganges sp. n., P. chinensis (Hsu) [=P. rarus (Tiunova and Levanidova) syn. n.], P. edmundsi sp. n., and the Oligocene fossil Potamanthellus rubiensis Lewis. Neoephemera [=Leucorhoenanthus Lestage syn. n.] includes N. maxima (Joly), N. purpurea (Traver), N. youngi Berner, N. bicolor McDunnough, and N. compressa Berner. Ochernova gen. n., includes O. tshernovae (Kazlauskas) comb. n. Taxa are described, illustrated and keyed. Species cladistics and biogeography are presented.  相似文献   

2.
3.
Heptageniidae is a species‐rich mayfly family (Ephemeroptera), whose taxonomy and phylogeny have been based almost exclusively on traditional morphological studies. Inconsistent use of diagnostic characters and the general lack of molecular studies have led to vague generic concepts, and the phylogenetic relationships among taxa in the family remain unclear. Afronurus Lestage is an Old World heptageniid genus of 66 species. The generic assignment of two species within this genus, A. kugleri Demoulin and A. zebratus (Hagen), has been the subject of much debate, because they share many apomorphic features that distinguish them from other congeners. We combined a thorough morphological study of all life stages of 28 representative heptageniid species with a molecular phylogenetic analysis of four mitochondrial and nuclear markers to resolve the generic position of A. kugleri and A. zebratus as well as the integrity of Afronurus and related genera. Our results confirm the monophyly of Afronurus and Electrogena and support the assignment of A. kugleri and A. zebratus to a newly described genus, Anapos Yanai & Sartori gen.n . We provide clear, diagnostic morphological characters for the genus and discuss the need for a thorough revision of generic concepts in the subfamily Ecdyonurinae. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:075E40C6-BAFE-4184-A2C2-E3BCFBC0BC15 .  相似文献   

4.
Summary

The effects of physical disturbance on larval populations of the mayfly Afroptilum sudafricanum Lestage were examined in the Naro Morn River, Kenya. Disturbance was induced by stirring, shifting and relocating streambed substrates by hand. The method aimed to simulate natural physical disturbance. The effects of continuous disturbance were examined by sampling larval populations at minute intervals of up to 14 minutes. The effects of periodic disturbance were examined by sampling larval populations which had been disturbed at intervals of minutes (short-term), hours (medium-term) and days (long-term). About 85% of A. sudafricanum individuals was removed from the streambed within four minutes of continuous physical disturbance. There were higher densities at night than during the day. All densities on the control sites for the medium-term disturbance experiments were significantly higher than those on the disturbed sites. Most of the post-disturbance densities on the medium-term disturbance sites were significantly lower than the pre-disturbance densities (Tukey's honestly significance difference test, α=0.05). There was no distinct density pattern on the sites exposed to long-term disturbances. Sites with the same disturbance regime appeared to react differently, some having dramatic fluctuations in density. Disturbance effects on A. sudafricanum density were multi-faceted with different expressions in time and space. It is concluded that A. sudafricanum is highly mobile and is capable of recolonizing disturbed areas within six hours. Their high mobility enables them to crawl into the deeper sediment layers during floods. However, recovery time depended not only on species mobility but also on how densely the sources of recolonization were populated and the frequency of disturbance. Slight increases, strong declines and negligible disturbance effects on the density of A. sudafricanum were evident. Afroptilum sudafricanum is highly mobile and is capable of rapid recolonization. It is concluded that physical disturbance affects A. sudafricanum populations in the Naro Morn River.  相似文献   

5.
Despite its wide, almost worldwide distribution, the mayfly genus Cloeon Leach, 1815 (Ephemeroptera: Baetidae) is restricted in the Western hemisphere to North America, where a single species is reported. In the Neotropics, except for some species wrongly attributed to the genus in the past, there are no records of Cloeon. Recently, however, specimens of true Cloeon were collected along the coast of Espírito Santo, Southeastern Brazil. In order to verify the hypothesis that this species was recently introduced to Brazil, our aim was to identify the species based on morphological and molecular characters and to confirm the presence of true representatives of the genus in the Neotropics. Our results revealed that the specimens found in Brazil belong to the Afrotropical species C. smaeleni Lestage, 1924. The identity of the species, its distribution, along with its previous absence in regularly sampled sites, is a clear sign that the specimens of C. smaeleni found in Espírito Santo are introduced, well established, and that the colonization took place very recently.  相似文献   

6.
ABSTRACT Two new species of the heptageniid mayfly genus Afronurus Lestage, Afronurus meo sp. n. and Afronurus mnong sp. n., are described from Vietnam with line-drawings of key characters. The larvae of A. meo can be characterized by rowed minute spines in the posterior margin of the abdominal terga 1-9 and distinct markings on anterior head, dorsal femora, and abdominal terga. The larvae of A. mnong can be characterized by scattered simple stout setae on the anterior margin and dorsal surface of femora, rowed acute spines on the posterior margin of abdominal terga 1-9, and plain brown body color. Their diagnoses, material data, distributions, and habitat and biological data are provided.  相似文献   

7.
8.
This study describes morphological changes in the male reproductive system of Miroculis amazonicus (Savage & Peters) from mature nymphs to subimago stages. The sperm ultrastructure of Massartela brieni (Lestage), Farrodes carioca (Domínguez et al) and Miroculis mourei (Savage & Peters), as well as aspects of cell fragments observed in these species' subimagos deferent ducts were described. Sperm from the three species studied are aflagellated and immotile, while those from F. carioca and Ma. brieni are approximately spherical with a homogenous nucleus and acrosome. Sperm of F. carioca present two or three mitochondria located between the nucleus and the acrosome. In Ma. brieni, only one lateral mitochondria was found. Sperm from Mi. mourei are shaped as a number 'eight', with electron lucent spots inside the nucleus and two mitochondria above the acrosome. Large cell fragments containing degenerative vesicles and some sperm were observed in the deferent duct lumen of the three species. Testes of Mi. amazonicus are extremely reduced in the subimago stage, which suggests that these cell fragments originated from testes degeneration.  相似文献   

9.
Abstract

A new species of Carabus (Lamprostus) from the province of Gilan, Iran, is described and illustrated: Carabus (Lamprostus) staveni sp. nov., Carabus (Pachystus) rechingerae Mandl, 1972, is considered a junior synonym of Carabus (Lamprostus) calleyi nigrinus Motschulsky, 1865. The specific status of Carabus (Sphodristocarabus) korgei Heinz, 1970, is restored (stat. rev.) and Carabus separatus delirensis Deuve, 2000, is considered to be a junior synonym of it. Carabus (Megodontus) stroganowi javahardensis Deuve, 2000, is considered to be a synonym of Carabus (Megodontus) heinrichi Mandl, 1966; both taxa are from the same type locality.  相似文献   

10.
The growth, reproduction and condition of adults of the three dominant fish species (roach, Rutilus rutilus, (L.); perch, Perca fluviatilis, L. and ruffe, Gymnocephalus cernuus, (L.)) in the eutrophic Lake Aydat were studied over one year cycle. Compared to published data, the growth of R. rutilus and G. cernuus was about average, while that of P. fluviatilis was below average. Comparing to literature, the fecundity of R. rutilus and G. cernuus was low but their oocytes were large. In contrast, P. fluviatilis had a high fecundity but small oocytes. At the end of summer, an abrupt decrease in the condition was recorded only for perch, probably due to stress as a result of environmental conditions. The sex-ratio was in favour of females for the three studied species but, in contrast to G. cernuus, the sex-ratio of R. rutilus and P. fluviatilis increased significantly also with age. It is concluded that Lake Aydat is a more favourable environment for R. rutilus and G. cernuus than for P. fluviatilis.  相似文献   

11.
AINTEGUMENTA (ANT) promotes initiation and growth of ovule integuments which cell fate is specified by ovule identity factors, such as SEEDSTICK (STK), SHATTERPROOF1 (SHP1) and SHATTERPROOF2 (SHP2). To study the genetic interaction between ANT and the ovule identity genes, we have obtained a stk shp1 shp2 ant quadruple mutant. The molecular and morphological characterization of the quadruple mutant and its comparison with the stk shp1 shp2 triple mutant, the shp1 shp2 ant triple mutant and the stk ant double mutant are here presented.  相似文献   

12.
Numerous individuals of the poorly known species Lecithostaphylus retroflexus (Zoogonidae) and Tergestia acanthocephala (Fellodistomidae) have been recovered from the teleost fish Belone belone gracilis from off the Scandola Nature Reserve, Western Mediterranean. They are redescribed, incorporating previously undescribed features: for L. retroflexus, a post-oral ring, a bipartite seminal vesicle, the shape of the excretory vesicle, the subterminal excretory pore and the flask-shaped gland-cells associated with the distinctly pedunculate ventral sucker; and for T. acanthocephala, the intestinal bifurcation in the forebody, necessitating its return to the genus Tergestia from Theledera. Additionally, T. acanthocephala is compared with T. laticollis from various species of Trachurus from the same geographical area.  相似文献   

13.
The genus Symbiodinium is the commonly observed symbiotic dinoflagellate (zooxanthellae) that forms mutual associations with various marine invertebrates. Numerous studies have revealed that the genus is comprised of a group of diverse taxa, and information on the phylogenetic relationships among the genus’ members is increasing. In this study, small subunit (SSU) ribosomal RNA (ssrRNA) gene sequences were determined for 15 more Symbiodinium strains from 12 relatively unstudied host taxa (Indo-Pacific tridacnids, cardiids, sponge, and soft coral), 1 hitherto unreported free-living Symbiodinium strain, and 4 other Symbiodinium strains from four other host taxa (Indo-Pacific zoanthid, foraminifer, jellyfish, and mid-Pacific hard coral). Their respective phylogenetic positions were inferred, and strains that are either closely related to or distinct from previously reported Symbiodinium taxa were revealed. The cultured Symbiodinium strains isolated from individuals of six species of tridacnids and three species of cardiids all had identical ssrRNA gene sequences, are closely related to S. microadriaticum Freudenthal, and are indistinguishable from the RFLP Type A strain previously reported. However, the ssrRNA gene sequences of clam symbionts that were obtained via gene cloning were different from those of the cultured isolates and represent strains that are close to the RFLP Type C strains. The Symbiodinium-like dinoflagellate from the Indo-Pacific sponge Haliclona koremella De Laubenfels is distinct from any of the Symbiodinium taxa studied and may be similar to the symbiont previously isolated from the stony coral Montipora patula Quelch. The isolates from the soft coral Sarcophyton glaucum Quoy et Gaimard and from the zoanthid Zoanthus sp. are both very closely related to S. pilosum Trench et Blank. The free-living Symbiodinium isolate is very closely related to the symbiont isolated from the Indo-Pacific foraminifer Amphisorus hemprichii Ehrenberg, which in turn is distinct from the Red Sea strain isolated from a similar host. Theisolate from Cassiopeia sp. is different from S. microadriaticum F., the type species harbored by Cassiopeia xamachana Bigelow, and is instead very closely related to S. pulchrorum Trench isolated from a sea anemone. The symbiont from the stony coral M. verrucosa Lamarck is a sister taxon to the symbionts isolated from the foraminifera Marginopora kudakajimensis Gudmundsson and Sorites orbiculus Forskål. These data suggest that polymorphic symbioses extend from cnidarians to some bivalve, foraminifer, and jellyfish host species.  相似文献   

14.
S Kubota  K Ikeda  J T Yang 《Biopolymers》1983,22(10):2237-2252
A series of sequential polypeptides (LysiRj)n (R is Leu, Ser, or Gly) and random copolypeptides, (Lysx, Leuy)n, were synthesized. Their conformation in NaDodSO4 solution was determined by CD. Only (Lys-Leu)n, (Lys-Ser)n, and (Lys3-Ser)n adopt a stable β-form in the surfactant solution; (Lys-Ser2)n, (Lys-Ser3)n, (Lys2-Ser2)n, and (Lys2-Ser)n have an unstable β-form, which reverts to an unordered form in high NaDodSO4 concentrations, even though both Ser and DodSO-bound Lys+ are β-formers. In contrast, (Lys-Gly)n remains unordered in NaDodSO4 solution. On the other hand, Lys-rich (Lys2-Leu)n forms an unstable helix and (Lys2-Leu2)n a stable helix in NaDodSO4 solution. In 25 mM NaDodSO4 (Lysx, Leuy)n also forms a helix up to x = 75 and reverts to the β-form at x = 90. This compares with the helical conformation of (Lysx, Alay)n up to x = 65 and its β-form at x = 90, suggesting that Leu is an even stronger helix-former than Ala. Our results may provide a plausible explanation for the increase in helicity and disruption of the β-form for many proteins in NaDodSO4 solution, that is, the polypeptide chain of a protein usually favors a helical conformation over a β-form in the presence of excess surfactant.  相似文献   

15.
Six clades are inferred from a phylogenetic analysis including 42 species belonging to the Empis (Coptophlebia) hyalea‐group. These clades are named as follows: E. (C.) acris, E. (C.) aspina, E. (C.) atratata, E. (C.) hyalea, E. (C.) jacobsoni and E. (C.) nahaeoensis. The presence of two dorsal more or less developed epandrial projections is considered autapomorphic for the E. (C.) hyalea‐group in addition to two characters previously found to support the monophyly of this group (presence of an unsclerotized zone in the middle of labella and epandrium unpaired). Amongst the cladistically analysed species, 24 are newly described [ E. ( C. ) acris , E. ( C. ) aspina , E. ( C. ) cameronensis , E. ( C. ) duplex , E. ( C. ) incurva , E. ( C. ) inferiseta , E. ( C. ) kuaensis , E. ( C. ) lachaisei , E. ( C. ) lamellalta , E. ( C. ) lata , E. ( C. ) loici , E. ( C. ) longiseta , E. ( C. ) mengyangensis , E. ( C. ) menglunensis , E. ( C. ) missai , E. ( C. ) nimbaensis , E. ( C. ) padangensis , E. ( C. ) parvula , E. ( C. ) projecta , E. ( C. ) pseudonahaeoensis , E. ( C. ) submetallica , E. ( C. ) urumae , E. ( C. ) vitisalutatoris and E. ( C. ) woitapensis ], five are reviewed [E. (C.) hyalea Melander, E. (C.) jacobsoni De Meijere, E. (C.) ostentator Melander, E. (C.) sinensis Melander and E. (C.) thiasotes Melander] and 13 were recently described in two previous papers. Two additional species, E. (C.) abbrevinervis De Meijere and E. (C.) multipennata Melander, are also reviewed but not included in the cladistic analysis since they are only known from the female. A lectotype is designated for E. (C.) jacobsoni. A key is provided to the six clades of the E. (C.) hyalea‐group as well as to species of each clade. A catalogue of the E. (C.) hyalea‐group, including 72 species, is given. The taxonomic status of 25 additional species mainly described by Bezzi and Brunetti, from the Oriental and Australasian regions, is discussed. The E. (C.) hyalea‐group is firstly recorded from the Palaearctic Region and Australia. Finally, the distribution and the habitats of the species compared with their phylogeny suggest a possible relationship between the diversification of the group and forest fragmentations during the Quaternary. © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society, 2005, 145 , 339–391.  相似文献   

16.
The covalent binding of trans-Pt (NH3)2Cl2 to the double-stranded poly(I)·poly(C) follows three types of reactions, depending on rb and the concentration of polynucleotide in the reaction mixture. At rb ? 0.1, the principal reaction is coordination to poly(I), giving rise to some destabilization of the double strand, as shown by uv and CD spectra, and a decrease in Tm values, giving rise to free loops of poly(C). At higher rb and low polynucleotide concentration, the free cytidine bases react with platinum bound on the complementary strand to form intramolecular (interstrand) crosslinks that restabilize the double-stranded structure. At high rb and high polynucleotide concentration, while the above reaction still occurs, the predominant one is the formation of intermolecular crosslinks. Under no conditions has strand separation been observed.  相似文献   

17.
The species of Ardeicola parasitic on the Ibis genus Threskiornis are reviewed-clayae Brelih, freemani sp.n., ibis Le Souef & Bullen, indicus Brelih, intermedia sp.n., nippon Hajela & Tandan-and a key for their identification is presented. Notes on the affinities of the species and a discussion on the distribution of Ardeicola on Threskiornis are included.  相似文献   

18.
A new scientific survey elucidates the preferred attack of stink bug Canthecona furcellata (Wolff.) (Hemiptera: Pentatomidae) on the spinning stage of the tropical tasar silkworm, Antheraea mylitta (Drury) (Lepidoptera: Saturniidae). The silkworm A. mylitta produces an excellent quality of wild silk; however, due to predation by C. furcellata, tasar silk production is reduced. The bug C. furcellata is the most invasive larval predator of A. mylitta and predation is high during early instars as well as the molting stage of the larvae. However, for the first time it is reported that the spinning stage is also preferable for attack by the stink bug. Both the nymphs and adults of C. furcellata attack the spinning silkworm; moreover, stink bug attack is observed in groups under field conditions. It is postulated that feeding preference is due to the concealed, non‐movable and less defensive stage of the tasar larvae during spinning. The predation of C. furcellata includes its approach on target larva of the tasar silkworm during spinning, where it inserts the proboscis inside the larval skin through the moist silk network of newly forming or formed cocoon. Most of the spinning larvae die from the attack and the normal seed cocoon fails to form. The mechano‐ and chemoreceptors, present on the antenna and proboscis of C. furcellata, play an important role in prey locating and the feeding mechanism. The life cycle of C. furcellata is also discussed in the present study.  相似文献   

19.
The unarmoured dinoflagellate Nusuttodinium aeruginosum retains a kleptochloroplast, which is a transient chloroplast stolen from members of the cryptomonad genus, Chroomonas. Both N. aeruginosum and the closely related N. acidotum have been shown to restrict their diet to a limited number of species of this blue‐green genus of cryptophyte. However, it is still unclear how flexible the predators are with regard to the ingestion and utilization of Chroomonas spp. as a source of kleptochloroplast. To address specificity of cryptomonad in N. aeruginosum, we collected the cells of N. aeruginosum from several ponds in Japan, and analysed the phylogeny of the kleptochloroplasts based on their plastidial 16S rDNA sequences. All sequences obtained in this study were restricted to only one (the subclade 4) of four subclades known to comprise the Chroomonas/Hemiselmis clade. Therefore, N. aeruginosum is specific in its dietary requirements, selecting their prey within the subclade level.  相似文献   

20.
The comparative floral ontogeny of five species belonging to the primuloid clade of the Ericales are investigated, viz. Maesa japonica, M. perlarius, Aegiceras corniculatum, Embelia laeta and E. ribes. All five species basically show 2/5-spiral phyllotaxis of the sepal primordia, although with some minor modification (particularly in Embelia, where the flowers are predominantly tetramerous). The phyllotaxis of the common petal-stamen primordia is also 2/5-spiral in the Maesa and Aegiceras species investigated, but appears to be unidirectional in Embelia. All five species develop common petal-stamen primordia in which the resultant petal primordia are larger than the stamen primordia, and in which the stamens develop proximally on the adaxial flank of the common primordia. Growth of the placenta in Maesa and Aegiceras partially embeds the ovules, but in Embelia the ovules are almost fully immersed in placental tissue at maturity. A comprehensive review of all previously published studies of floral ontogeny of primuloid genera is presented, and the phylogenetic significance of the variation between genera is evaluated with reference to recently published cladograms.  相似文献   

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