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The Crenicichla mandelburgeri species complex from the Middle Paraná shows parallel evolution of ecomorphs to the unrelated C. missioneira species complex from the Uruguay River. In this article, we describe a new species from the C. mandelburgeri species complex that has evolved a parallel morphology and ecology to an unrelated species from the C. missioneira species complex (C. celidochilus). The new species is a pelagic predator that feeds predominantly on fishes and together with C. celidochilus is the only known pelagic species in the large riverine genus Crenicichla. The new species is endemic solely to a small tributary (the Urugua-í) of the Middle Paraná River where it is sympatric and partly syntopic with two other closely related endemic species that, however, differ strongly in their ecomorphologies (one is a generalistic invertivore and the other a specialized molluscivore). Mitochondrial DNA phylogeny finds the new species nested within the widespread C. mandelburgeri. Reduced genome-representation ddRAD analyses, however, demonstrate that this new species is of a hybrid origin and shares ancestry with C. ypo, one of the two studied sympatric species.

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Carex sinosupina, a new species from Gansu, China is described and illustrated. This species is similar to C. aridula and C. ivanoviae, but differs by having broader leaves, 2.0–3.5 mm wide, perigynia 3–5‐veined abaxially and achenes concave at the middle of one lateral surface. Based on a field survey and SEM (scanning electron microscope) observation of the micromorphology of perigynia and achenes, the morphology and micromorphology of the new species, C. aridula and C. ivanoviae is compared.  相似文献   

5.
Lagerstroemia menglaensis C. H. Gu, M. C. Ji & D. D. Ma, a new species of Lythraceae from Xishuangbanna, Yunnan, China is described and illustrated. The morphological characteristics of the new species and two morphologically similar species (L. guilinensis and L. venusta) are compared, and a key to distinguish between them is provided.  相似文献   

6.
Chassalia magnificens, a new species from the Albertine Rift in eastern Democratic Republic of Congo, is described and illustrated. The species is recognised inter alia by its large stipules and montane habitat. Chassalia chrysoclada is a new combination for a widespread, but hitherto overlooked, central African species originally described in the genus Psychotria. Chassalia chrysoclada is related to C. pteropetala (K. Schum.) Cheek but lacks the bicostate twigs and dorsally winged corolla lobes of that species.  相似文献   

7.
A new species of Crocus sect. Crocus is described as an endemic of Elba Island (Tuscan Archipelago, Italy): C. ilvensis Peruzzi & Carta sp. nov. (2n=8). The new species was wrongly referred to C. corsicus Vanucchi (2n=18), C. etruscus Parl. (2n=8) or C. vernus Hill. subsp. vernus (2n=8, 16) by previous authors. Its karyotype structure, asymmetry and chromosome dimensions show affinity with C. etruscus, and no clear relations with other related taxa. From a morphological point of view, C. ilvensis appears intermediate between C. etruscus and C. vernus subsp. vernus, showing however a peculiar combination of character‐states. The new species is completely allopatric with other Crocus sect. Crocus taxa and its possible role in the origin of tetraploid races of C. vernus is discussed.  相似文献   

8.
A new species of Campylocentrum from the Colombian Andes, C. guarinae, is described, illustrated and placed within a key to Colombian species of the genus. The new species resembles C. lansbergii from which it differs in vegetative and floral characters. The main differences between these species are described and illustrated.  相似文献   

9.
Cylicocyclus asini n. sp. is described from the ventral colons of seven domesticated donkeys Equus asinus in South Africa. The specimens are smaller than 11 members of the genus Cylicocyclus, which currently comprises 10 recognised species, one recognised subspecies and two species inquirendae, but is similar in size to the two smaller species, C. ashworthi and C. leptostomum. Additionally, the small size of its buccal capsule places it within the so-called small buccal capsule group, namely C. ashworthi, C. leptostomum, C. nassatus, C. radiatus and C. triramosus. The shape of the oesophagus at the oesophago-intestinal junction is elongate, similar to that of C. leptostomum. The female specimens have a tail length shorter than the vulva to anus distance, similar to three of the smaller Cylicocyclus species, namely C. leptostomum, C. radiatus and C. triramosus. The new species is distinguished from the smaller members of the genus by the presence of a `club-foot' posterior in the female specimens, 40–46 elements in the external leaf-crown and a deep division of the dorsal ray which extends beyond the origin of the externodorsal ray. Similarly, the new species can be separated from the two other members in the genus with a `club-foot' posterior in the females (C. auriculatus and C. gyalocephaloides) by its body length (6.6–8.47 mm) and the presence of a nipple-like dorsal gutter.  相似文献   

10.

The genus Ctenomys includes a high number of taxa, with at least ten species from Patagonia and three recently described species for northeastern Chubut Province (Argentina). Ctenomys sociabilis is a social species of the genus Ctenomys and is currently distributed in the surrounding area of Sierra Cuyin Manzano (Neuquén Province), with a recently extinct population that occurred in Laguna Nahuelquir (Cushamen, Chubut Province). Molecular analyses have placed C. sociabilis at the base of Ctenomys clade, as the sister species to all other Ctenomys. Based on a morphological assessment (qualitative and quantitative) and DNA sequencing, we describe a new species of Ctenomys from Esquel, Chubut Province. Phylogenetic analysis shows the new species to be closely related to C. sociabilis, with evidence of solitary behavior. This new species is the first reported to be closely related phylogenetically to Ctenomys sociabilis at the base of the Ctenomys phylogeny. We provide anatomical comparisons between the new species and other species of Ctenomys from Patagonia, especially C. sociabilis.

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11.
The new brown algal species Cladosiphon takenoensis H. Kawai (Chordariaceae, Ectocarpales s.l.) is described from Takeno, Hyogo, Japan based on morphology and DNA sequences. The species is a spring annual, growing on subtidal rocks at more or less exposed sites. It resembles C. umezakii in its gross morphology, and the two often grow together, but is distinguishable from C. umezakii in having a more hairy appearance. Cladosiphon takenoensis has a slimy, cylindrical, multiaxial and sympodial erect thallus, branching once to twice, and is provided with long assimilatory filaments (up to 1.8 mm long, composed of up to 100 cells). Unilocular zoidangia are formed on the basal part of assimilatory filaments. The species is genetically most related to C. umezakii and has the same basic thallus structures, but differs from C. umezakii and other Cladosiphon species in lacking phaeophycean hairs and plurilocular zoidangia of the assimilatory filaments. DNA sequences of the mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes and the nuclear rDNA ITS2 region support the distinctness of the species. The genus Cladosiphon was paraphyletic in our analyses because the clades of C. okamuranus/C. zosterae and C. takenoensis/C. umezakii were split by Mesogloia vermiculata. However, since the genus‐level taxonomy of Chordariaceae needs considerable revision, we suspend the genus‐level taxonomy of the new species, and tentatively describe it as C. takenoensis.  相似文献   

12.
Five species belonging to the family Prymnesiaceae (one Prymnesium and four Chrysochromulina) have been identified in cultures obtained from water collected in the Bay of Banyuls‐sur‐Mer (Mediterranean Sea, France) using LM, SEM, and TEM. Two are described as new species, Chrysochromulina lanceolata sp. nov. and C. pseudolanceolata sp. nov. Both species are large and lanceolate with an acute posterior and two anterior arms. They are easily detectable with LM but difficult to distinguish to species level with live cells, without experience. EM reveals two completely different scale patterns in the two species. Cells of C. lanceolata are 21–38 μm long, 7–12 μm wide, and 3–7 μm thick. They possess two subequal flagella (30–51 and 29–44 μm), and the haptonema is shorter than the flagella (23–37 μm). The cell body is covered by plate and spine scales. Cells of C. pseudolanceolata sp. nov. are slightly smaller (15–18 × 6–8 μm) with more rounded extremities, two subequal flagella (19–26 and 17–24 μm), and the haptonema is longer than the flagella (about 35 μm). Three types of plate scales are observed in this species. Other findings are C. alifera Parke et Manton and C. throndsenii Eikrem (a new record for the Mediterranean Sea). Prymnesium faveolatum Fresnel, a new toxic species recently described, is illustrated with both LM and SEM.  相似文献   

13.
Three Cocconeis Ehrenberg species, epiphytic on the leaves of Posidonia oceanica (L.) Delile, were studied by light and electron microscopy. A new species, C. pseudonotata, is described which is closely related to C. notata Petit and C. diruptoides Hustedt. Gross morphology and the presence of a sigmoid raphe and sternum are the characters shared by the three species, whereas the central areas of sternum and raphe-sternum valves, and the stria and areola densities are the main distinctive characters for the species when observed by light microscopy. Scanning and transmission electron microscopic observations revealed that the fine structure of areolae must be also considered in order to identify the species. Comparison among the three species has been carried out by observations on material from our samples, as well as on the type material of C. diruptoides and cleaned samples from the Hustedt collection. The study also provides new information on the geographical distribution of these species.  相似文献   

14.
Carex yandangshanica C. Z. Zheng & X. F. Jin, a new species of Carex sect. Rhomboidales Kükenth. from Zhejiang, China, is described and illustrated. The new species is similar to C. thibetica Franch. and C. brevicuspis C. B. Clarke, but differs from the former by having trabeculate leaves, pistillate spikes with 6–10 staminate flowers or without staminate flower at the apex, and achenes at apex contracted into a slightly curved beak, and from the latter by having lateral culms, trabeculate leaves, and elliptic, rubiginous and awned pistillate scales. SEM microphotographs of perigynia and achenes are provided for the new species and related taxa.  相似文献   

15.
A new species of Chiritopsis (Gesneriaceae), C. danxiaensis W. B. Liao, S. S. Lin & R. J. Shen, is described and illustrated from Mount Danxiashan, Guangdong Province, China. The new species is morphologically closely related to C. lobulata and C. cordifolia, but is characterized by having denticulate bracts, yellowish corolla, 2 glabrous staminodes and longer style. A revised key to all species of the genus is also provided.  相似文献   

16.
Carex dapanshanica X. F. Jin, Y. J. Zhao & Z. L. Chen, a new species of Cyperaceae from Mount Dapan, Zhejiang Province, eastern China is described and illustrated. The new species is morphologically similar to C. chungii C. P. Wang, but differs in having 2 or 3spikes, pistillate scales with brown margins and short‐awned at apex, and glabrous perigynia. Micromorphological photographs of the achenes of C. dapanshanica and C. chungii under SEM (scanning electron microscope) are provided as well.  相似文献   

17.
Cousinia kermanensis sp. nov. (sect. Congestae Bunge) and C. pulcherantha sp. nov. (sect. Leiocaules Bunge) are described from Kerman in southeastern Iran. These species are compared to their closest related species, C. decurrens Regel and C. oophora Rech. f., respectively. The habitat of C. kermanensis is lowland mountains or hills with poor soils inside the steppe of Artemisia sieberi Besser. Cousinia pulcherantha grows on highland slopes of mountains with deep soils inside the steppe of Artemisia aucheri Boiss. Illustrations of the new species are presented.  相似文献   

18.
A new species of Urticaceae, Parietaria taiwania C. L. Yeh & C. S. Leou is described and illustrated. The new species is related to P. micrantha Ledebour, but can be distinguished from it by being a perennial herb with climbing or pendulous stems, leaves that are sparsely pubescent on the adaxial side, unisexual flowers, male flowers without bracts and female flowers with a bract. This is the first record of a species of Parietaria in Taiwan.  相似文献   

19.
Seven species of the genus Cosmospora collected in Japan are reported in this article. Among them, Cosmospora japonica is described as a new species. Cosmospora henanensis, C. rishbethii, and C. triqua, all of which are known only from their type localities, are added to the Japanese mycobiota. The other species, C. chaetopsinaecatenulatae, C. diminuta, and C. peponum, are new records for Japan. Additional distribution records are given for Cosmospora species hitherto known in Japan.  相似文献   

20.
Ulrich Einsle 《Hydrobiologia》1996,319(3):167-177
Some of the species within the genus Cyclops O. F. Müller, 1785 can only be determined exactly by combining different methods and techniques. Based on the comprehensive analysis of morphometrical data, some populations in periodical ponds near Lake Constance were examined for their pattern of chromatin diminution and were compared by enzyme electrophoresis. These studies provided evidence of two new species. Together with C. furcifer Claus, 1857 and C. vicinus Uljanin, 1875 one of the ponds (‘Litzelsee’) was inhabited by four Cyclops species. In addition to morphological differences and distinct electrophoretic characteristics, C. furcifer and the new species differ in the timing of their chromatin diminution: C. singularis in the fourth, C. heberti in the fifth, and C. furcifer in the sixth cleavage. The qualitative course of chromatin diminution is rather similar in all three species. The same combination of three Cyclops species (without C. vicinus) was also found in an older sample (1990) from another ephemeral pond near Lake Constance. A close genetical relationship between the three species seems probable.  相似文献   

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