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1.
The previously unknown larvae and pupae of Nasiternella regia Riedel, 1914 (Diptera, Pediciidae) are described and illustrated from specimens collected in water-filled tree holes in deciduous forests in Slovakia. Brief comments on their ecology and behaviour are provided. Comparisons are made to the larvae of Nasiternella varinervis (Zetterstedt, 1851) as described by Krivosheina (2009).  相似文献   

2.
3.
Elasmobranch fossils recovered from the Fishburne Formation (lower Eocene/Ypresian) of Berkeley County, South Carolina, USA, include species from four genera of sharks and six genera of rays. Of particular interest was the recovery of multiple isolated teeth from a new genus and species of the cownosed ray family Rhinopteridae, which is the focus of this study. The unique crown morphology separates this genus and species from Rhinoptera. Eorhinoptera grabdai, gen. et sp. nov., is represented by small, bar-shaped teeth in the shape of greatly elongated hexagons. These teeth are the isolated elements of a dental plate. The holotype, with 12 wide root lobes, is the most elongated in the sample being 1 cm long and 1.5 mm wide, indicating an origin in the central region of the plate. Paratypes are less elongated, have 4–8 root lobes and are from more lateral rows. The crown is smooth and has a distinctly convex occlusal surface. Eorhinoptera is only the second genus of cow-nosed ray. Its distinctive crown morphology may have allowed it to exploit different kinds of prey than those favoured by rays that lacked convex tooth crowns.  相似文献   

4.
Craneflies (Diptera Tipuloidea) are a typical but poorly known insect group in various moist environments, such as mires. The area of natural mires has strongly decreased in Finland, and there is an urgent need to study and describe the fauna of mires and to determine whether different mire categories support different assemblages of craneflies that might have indicator value. Craneflies were studied using Malaise traps in the Kauhaneva mire system in minerotrophic and ombrotrophic sites, the former subdivided into meso- and oligotrophic sites. A total of 29 cranefly species were recorded. Species richness was highest in mesotrophic sites while the number of species was equally low in oligo- and ombrotrophic sites. Phylidorea squalens, Erioptera flavata, Pedicia rivosa and Tricyphona immaculata were identified as indicators for mesotrophic sites, but no indicators were found for oligo- or ombrotrophic sites. No differences between the species composition of minerotrophic (meso- and oligotrophic combined) and ombrotrophic sites were detected, but when three classes of trophic status were compared, a statistical difference was found. Cranefly species richness in Kauhaneva was low compared to pristine spring habitats. Our results imply, that a focus towards conservation and restoration of mire types with high trophic status would benefit also the conservation of cranefly diversity in the boreal ecoregion. Bioassesments and ecological surveys of craneflies should be designed to cover adequately all trophic status classes within a mire, and especially the mire types with highest trophic status. We also review the distribution and ecology of some potentially regionally threatened cranefly species.  相似文献   

5.
Zusammenfassung Die Feinstruktur der Maxillarnephridien von Scutigerella immaculata Newport mit ihren drei Abschnitten Sacculus, Tubulus und Ausführgang wurde untersucht. Die Zellen des Sacculus sind typische Podocyten, an denen eine Ultrafiltration ablaufen kann. Möglicherweise wird die Filtration durch einen den Sacculus umgebenden Muskel unterstützt. Die Zellen des Tubulus zeigen basale Einfaltungen und im proximalen Teil auch Mikrovilli. Sowohl im Tubulus als auch im Ausführgang, dessen Zellen ebenfalls basale Einfaltungen aufweisen, werden Reabsorptionsprozesse vermutet.
The fine structure of the maxillary kidney of the garden centipede, Scutigerella immaculata Newport (Symphyla, Myriapoda)
Summary The fine structure of the maxillary kidney of Scutigerella immaculata Newport (Symphyla) has been investigated. It may be compared with segmental organs of other Arthropoda having an end-sac which forms a primary urine by ultrafiltration. The filtration may be supported by a muscle surrounding the end-sac. The tubular part of the nephridium and the efferent duct show structures which may be involved in reabsorption.
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6.
An investigation of a virulent Bacillus phage-K2 (named Bp-K2) isolated from chungkookjang (a fermented soybean foodstuff) was made. Bp-K2 differed in infectivity against a number of Bacillus subtilis strains including starter strains of chungkookjang and natto, being more infectious to Bacillus strains isolated from the chungkookjang, but much less active against a natto strain. Bp-K2 is a small DNA phage whose genome size is about 21 kb. Bp-K2 is a tailed bacteriophage with an isometric icosahedral head (50 nm long on the lateral side, 80 nm wide), a long contractile sheath (85–90 nm × 28 nm), a thin tail fiber (80–85 nm long, 10 nm wide), and a basal plate (29 nm long, 47 nm wide) with a number of spikes, but no collar. The details of the structures of Bp-K2 differ from natto phage ϕBN100 as well as other known Bacillus phages such as SPO1-like or ϕ 29-like viruses. These data suggest that Bp-K2 would be a new member of the Myoviridae family of Bacillus bacteriophages.  相似文献   

7.
Encyrtus sugonjaevi Simutnik sp. n. is described from Israel. The new species has a bow-like, transverse frontofacial carina extending across the entire width of the head, and the genae with a poorly developed carina. This species clearly differs from the other species of the genus in the following characters: the funicle is wide and flat, with the 1st segment 1.5 times as long as wide; the basal part of the fore wing is glabrous from its base to a transverse band of coarse setae; the transverse band is well developed, bears long and thick setae.  相似文献   

8.
Three species of the genus Teratorhabditis (Osche, 1952) Dougherty, 1953 collected from sewage and manure samples of North India are described. The species T. andrassyi Tahseen & Jairajpuri (1988) synonymised by Sudhaus (1991) has been reinstated and is characterized by oviparous females having bluntly rounded lips with labial sensilla not raised beyond labial contour; lip margins and axils heavily cuticularised; three lines in lateral field; considerably wide and tubular stoma having swollen metastegostomal walls with prismatic inner lining bearing five teeth on each plate; basal bulb with usually single haustrulum; tail conoid with a terminal spike; eggs with ridged shells and males with 40–45% distally-fused spicules and a smooth, non-indented bursa having slender papillae in 2/4 + p + 3 configuration. Other populations identified as T. synpapillata and T. palmarum Gerber and Giblin-Davis (1990) are reported for the first time from India. An identification key to species is provided. Relationships within the genus are discussed. Electronic supplementary material Supplementary material is available for this article at and accessible for authorised users Handling editor: K. Martens  相似文献   

9.
Community structure at local scales is a major factor controlling population and community dynamics of plant species. Dicerandra immaculata Lakela var. immaculata (Lamiaceae) is a critically endangered plant known only from a few locations in scrub habitat in Florida. Using seven sites where populations of D. immaculata were wild, introduced, and/or extirpated, we sought to answer the following questions: (1) how do habitat characteristics at locations supporting wild D. immaculata plants vary from random locations within the same habitat; (2) how do habitat characteristics differ between wild and extirpated populations; and (3) how do habitat characteristics differ between wild and introduced populations? At locations of wild D. immaculata, community structure had fewer woody stems, shorter understory vegetation, lower percent canopy coverage, and lower percent ground cover of detritus than random locations and locations with extirpated D. immaculata. In addition, bare ground decreased at extirpated locations because other plant species expanded their coverage, water saturation of the soil increased, diversity of shrubs decreased, and composition of the overstory changed compared to that of wild locations. Habitat characteristics associated with introduced plants were more similar to characteristics at randomly chosen locations than those with wild plants. However, introduced plants tended to occupy locations that had drier soil, a higher abundance of conspecifics, and a higher proportion of woody understory plants than that of random locations. Overall, gaps in the canopy and at ground level are likely essential for survival and recruitment of D. immaculata.  相似文献   

10.
Abstract The paper deals with the morphology of the larva of Ctenophthalmus quadratus. It can be distinguished from Ctenophthalmus arvalis by the anterior part of the egg burster being longer, 1.6 to 1. 8 times as long as the posterior part, number of mandibular teeth and number of the setae of anal comb.  相似文献   

11.
Dinoflagellate associations, including toxic and potentially toxic benthic species, were examined in sand from South Water Cay and Carrie Bow Cay, Belize. The inshore sand habitat in localized areas of warm shallow lagoonal waters supported blooms of toxic assemblages of dinoflagellates. In the sand, the dominant microalgae were dinoflagellates; cyanobacteria were a minor component and diatoms were absent. Ciliates and nematodes were present. Assemblages of microorganisms in colored sand were examined for 4 consecutive days after which a storm washed away the patch. The sand-dwelling dinoflagellate assemblage included 16 species where densities ranged from as low as 1.3% to 15% of total cell densities. The dominant species was Scrippsiella subsalsa, having 1.8 × 105 to 2.6 × 105 cells g-1 sand. Toxic dinoflagellates identified in the sand were Gambierdiscus toxicus, Ostreopsis lenticularis, Prorocentrum lima, Prorocentrum mexicanum, and Amphidinium carteri. The potentially toxic Ostreopsis labens, Gambierdiscus belizeanussp. nov., and Coolia tropicalis sp. nov. were also identified. Toxic and potentially toxic species represented 36% to 60% of total microalgal cell assemblage. The morphology of a new sand-dwelling species, Gambierdiscus belizeanus sp. nov., was examined with the scanning electron microscope. The plate formula was Po, 3′, 7″, 6c, s?, 5?, 1p, and 2″″.Dimensions of G. belizeanus cells were 53–67 pm long, 54–63 μm wide, and 92–98 μm in dorsoventral depth. Cells were deeply areolated, ellipsoid in apical view, and compressed anteroposteriorly. The cells of G. belizeanus were identified by the cell's long, narrow, pentagonal, posterior intercalary plate (1p) wedged between the wide postcingular plates 2″’and 4″; 1p occupied 20% of the width of the hypotheca. The plate formula for Coolia tropicalis sp. nov. was Po, 3′, 7″, 7c, 8s?, 5″″, and 2″″, Cell size ranges were 23–40 μm long, 25–39 μm wide, and 35–65 μm in dorsoventral diameter. Cells were spherical, smooth, and covered with scattered round pores. The epitheca was smaller than the hypotheca. Precingular plates 1″ and 7″ were small and narrow, and the first apical plate 1″ and precingular plate 6″ were the largest plates on the epitheca. The apical pore was straight and 7 μm long, and was situated in the apical plate complex. Cells of C. tropicalis were distinguished from C. monotis by the wedge-shaped plate 1′, a four-sided 3’plate, and a short apical pore.  相似文献   

12.
The larval and pupal morphology of Atypophthalmus inustus (Meigen, 1818) are described for the first time. The main diagnostic characters are the following: head capsule massive, frons with 3 short terminal projections, hypostomium with 11 teeth and long narrow split, hypopharynx and labium with well-developed conical teeth, stigmal area with 2 long ventral pigmented spots.  相似文献   

13.
Summary Macrocilia are compound ciliary feeding organelles found inside the mouth of beroid ctenophores. Each macrocilium contains multiple 9+2 axonemes surrounded by a common membrane and bears a distinct capping structure at the distal end. The cap consists of extensions of axonemal microtubules that are embedded in an electron-dense matrix to form pointed projections or teeth. The teeth change from a straight to a hooked configuration during the beat cycle of macrocilia, and these changes in tip shape are thought to aid ingestion and/or breakup of prey. Using light and electron microscopy we found a remarkable diversity in macrociliary size, tooth pattern, and distribution among traditional morphospecies of Beroe. These differences distinguish two major groups of Beroida. Group 1 includes most of the described nominal species [B. cucumis, B. abyssicola, B. ovata, B. gracilis, and B. sp. (Gloria)]. Their macrocilia are relatively small (typically 25–30 m long, 5 m diameter) and are restricted to a band around the inside of the lips. Two main types of macrociliary tooth patterns are found: 3–12 equally-sized teeth [B. cucumis (Mon), B. ovata, B. sp. (Gloria)] or 3 teeth with the middle tooth being larger (B. cucumis (CC), B. gracilis) or smaller (B. abyssicola). Group 2 species (B. forskali, B. mitrata) have greatly flattened bodies and wide mouths. Their macrocilia cover an extensive area of the stomodaeal cavity, and are longer and stouter (80–100 m long, 12–15 m in diameter). The shaft of the macrocilium is not hexagonal in transverse section, as in Group 1 species, but is wedge-shaped, being broader on the recovery-stroke (oral) side. The macrociliary tips are blunt and finely serrated, bearing one or more rows of 10–12 short teeth running at right angles to the beat plane. This diversity in macrociliary patterns is apparently related to differences in diet, feeding methods, and/or mechanism of prey digestion among various species. However, direct evidence for the functional significance of macrociliary diversity has not yet been obtained. The macrociliary patterns may be useful for clarifying problems of species identification and relationships within the Beroida. In particular, macrociliary differences found between and within traditionally distinguished morphospecies of Beroe raise the possibility of the existence of complexes of sibling species in this group.  相似文献   

14.
Three new dinoflagellate species, Gambierdiscus polynesiensis, sp. nov., Gambierdiscus australes, sp. nov., and Gambierdiscus pacificus, sp. nov., are described from scanning electron micrographs. The morphology of the three new Gambierdiscus species is compared with the type species Gambierdiscus toxicus Adachi et Fukuyo 1979, and two other species: Gambierdiscus belizeanus Faust 1995 and Gambierdiscus yasumotoi Holmes 1998. The plate formula is: Po, 3′, 7", 6C, 8S, 5‴, 1p, 2". Culture extracts of these three new species displayed both ciguatoxin- and maitotoxin-like toxicities. The following morphological characteristics differentiated each species. 1) Cells of G. polynesiensis are 68–85 μm long and 64–75 μm wide, and the cell’s surface is smooth. They are identified by a large triangular apical pore plate (Po), a narrow fish-hook opening surrounded by 38 round pores, and a large, broad posterior intercalary plate (1p) wedged between narrow postcingular plates 2‴ and 4‴. Plate 1p occupies 60% of the width of the hypotheca. 2) Cells of G. australes also have a smooth surface and are 76–93 μm long and 65–85 μm wide in dorsoventral depth. They are identified by the broad ellipsoid apical pore plate (Po) surrounded by 31 round pores and a long and narrow 1p plate wedged between postcingular plates 2‴ and 4‴. Plate 1p occupies 30% of the width of the hypotheca. 3) Cells of G. pacificus are 67–77 μm long and 60–76 μm wide in dorsoventral depth, and its surface is smooth. They are identified by the four-sided apical pore plate (Po) surrounded by 30 round pores. A short narrow 1p plate is wedged between the wide postcingular plates 2‴ and 4‴. Plate 1p occupies 20% of the width of the hypotheca. These three newly described species were also characterized by isozyme electrophoresis and DNA sequencing of the D8–D10 region of their large subunit (LSU) rRNA genes. The consistency between species designations based on SEM microscopy and classification inferred from biochemical and genetic heterogeneities was examined among seven isolates of Gambierdiscus. Their classification into four morphospecies was not consistent with groupings inferred from isozyme patterns. Three molecular types could be distinguished based on the comparison of their LSU rDNA sequences. Although G. toxicus TUR was found to be more closely related to G. pacificus, sp. nov. than to other G. toxicus strains, the molecular classification was able to discriminate G. polynesiensis, sp. nov. and G. australes, sp. nov. from G. toxicus. These results suggest the usefulness of the D8–D10 portion of the Gambierdiscus LSU rDNA as a valuable taxonomic marker.  相似文献   

15.
Phyllodiaptomus wellekensae n. sp. is described from south India. In the female, the genital somite is dilated at the left proximal margin and armed with an extraordinarily large, somewhat curved, laterally-directed spine; the right genital spine is much smaller than the left one. The terminal claw of leg 5 has a secretory pore at its tip and a characteristic conveyor canal on its anterior surface. In the right male P5, the coxal plate is short and unique in shape. The basis is 1.3 times as long as wide, with a long, sinuous, hyaline lamella on its medial margin. The first exopodite segment is short and optuse at its outer distal corner. The second segment is rectangular and has a short, hyaline, spinous projection between the lateral spine and the terminal claw. The left P5 has a large, serrate, hyaline fan between its apical thumb and medial apical seta. P. tunguidus is redescribed based on material newly collected from three localities in China.  相似文献   

16.
《Journal of bryology》2013,35(2):126-132
Abstract

Two new species of Lejeunea Lib., L. kashyapii sp. nov. and L. mehrana sp. nov. are described from Sikkim, India. The former is characterized by sub-orbicular leaves; first tooth of leaf lobule, 1–3 cells long 1–2 cells wide at base; reniform underleaves slightly wider than long; monoicous sexuality; 2–3-paired male bracts; obcordate perianth with 4–5 smooth keels (2 lateral, auriculate; 2 ventral; 0–1 dorsal, indistinct). Whereas, the latter is characterized by oblong – ovate leaves; lobule 1/6–1/5 as long as lobe; distant – contiguous underleaves with 1–3 teeth on each lobe; dioicous (?) sexuality; 2–4-paired male bracts and 1–2 male bracteoles present near the base of androecia. A key to the Indian species of the genus are provided.  相似文献   

17.
A new thecate, photosynthetic, sand‐dwelling marine dinoflagellate, Laciniporus arabicus gen. et sp. nov., is described from the subtidal sediments of the Omani coast in the Arabian Sea, northern Indian Ocean, based on detailed morphological and molecular data. Cells of L. arabicus are small (16.2–30.1 μm long and 13.1–23.2 μm wide), dorsoventrally compressed, with a small apical flap‐shaped projection pointing to the left. The thecal plate pattern is distinguished by minute first precingular plate and sulcus, which extends into the epitheca, with large anterior and right sulcal plates. The Kofoidian thecal tabulation is Po, X, 4′, 2a, 7′′, 6c, 6s, 5′′′, 2′′′′. Morphologically, the revealed plate pattern has an affinity to the Peridiniales, and LSU rDNA based phylogenetic analyses placed L. arabicus within the Thoracosphaeraceae, close to calcareous‐cyst producing scrippsielloids, predatory pfiesteriaceans, and photosynthetic freshwater peridinioids Chimonodinium lomnickii and Apocalathium spp. However, the thecal plate arrangement of L. arabicus differs noticeably from any currently described dinoflagellates, and the species stands out from closely related taxa by extensive differences in physiology and ecology.  相似文献   

18.
The ant genus Solenopsis Westwood 1840, is recorded for the first time in Saudi Arabia. The worker caste of S. saudiensis n. sp., collected in Riyadh is described and illustrated. This resembles S. cooperi Donisthorpe 1947, and S. kochi Finzi 1936. A revised key to the Arabian species is given together with ecological and biological notes. S. saudiensis n. sp. is identified by the following characters: Anterior clypeal margin with a central pair of stout projecting teeth and a lateral pair of short, broad basal blunt teeth; eyes with two minute facets; funicular segments 2–7 about twice as wide as long; propodeum short and low with the basal face making a continuous arc with the declivity; and petiole as long as broad in dorsal view.  相似文献   

19.
Semionotus bergeri Agassiz, 1833, from the Upper Triassic (Carnian) of southern Germany, the type species ofSemionotus, is here described in detail for the first time, including so far unstudied material in the Naturkunde-Museum Coburg, which allows a fairly complète reconstruction of this fish. The species is diagnosed by the présence of long frontals, about 4 times longer than wide, with antorbital lateral processes, 6–7 posterior infraorbitals, infraorbital at the posteroventral corner of the orbit notably larger than adjacent ones, infraorbitals at the posterior border of the orbit being as deep as long, and the middle élément anteroventrally expanded, dorsal fin base about two times the anal fin base.S. elegans from the Late Triassic-Early Jurassic of the Newark Supergroup in North America, is so far the best know species ofSemionotus and is the only species of this genus that has been included in phylogentic analyses. However, the comparison ofS. bergeri with other proposed speciesof Semionotus, such asS. elegans, and other semionotids casts doubt on the monophyly of this genus as currently understood, since these species exhibit a mosaic distribution of characters.   相似文献   

20.
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