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21.
Hedwig Hirschmann 《Journal of nematology》1986,18(4):520-532
Meloidogyne hispanica n. sp. is described and illustrated from specimens obtained from peach rootstock, Prunus persica silvestris Batsch, from the Seville district of Spain. The perineal pattern of the female is oval shaped to rectangular with low dorsal arch and often widely spaced lateral lines with fringe-like striae. The stylet, 14.1 μm long, has broad, distinctly set off knobs. Males have a high, rounded head cap that slopes posteriorly. Labial disc and medial lips are fused to form elongate lip structures. The robust styler, 23.5 μm long, has large, rounded knobs that are slightly set off from the shaft. Mean second-stage juveniles length is 392.6 μm. The truncate head region is generally not annulated. The distinctly rounded and raised labial disc and the crescent-shaped medial lips form dumbbell-shaped lip structures. The stylet, 11.1 μm long, has rounded, posteriorly sloping knobs. The slender tail, 46.4 μm long, has large irregular-sized annules in the posterior region and ends in a bluntly rounded tip. Tomato was a good host; tobacco, pepper, and watermelon were poor hosts; cotton and peanut were nonhosts. Meloidogyne hispanica n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of 2n = 33-36. The esterase pattern is unique among Meloidogyne species. 相似文献
22.
Phylogenetic relationships of Prosopium gemmifer, P. spilonotus, P. williamsoni, P. cylindraceum and P. coulteri species were determined based on variation at 37 allozyme loci, and compared with Stenodus and nine species of Coregonus. Of the three genera, Prosopium was the most distinct with Nei genetic distances to Coregonus of D=0·55—1·05 and to Stenodus of D=0·58—0·92. Stenodus and Coregonus were closely related but grouped as sister taxa with a mean genetic distance of 0·31 (range 0·22—0·40). These results agree with the degree of morphological differentiation among the genera as well as with observations concerning hybridization, e.g. many Coregonus species hybridize with Stenodus, but no natural hybrids are known between Prosopium and other coregonines. Within Prosopium, P. coulteri was the most divergent species branching out at D=0·51 from the others and followed by P. cylindraceum at D=0·28. The three remaining species are closely related. Among them P. williamsoni joins P. gemmifer and P. spilonotus at 0·04, and the distance between the two Bear Lake endemics is only 0·004. The distance between P. cylindraceum and the remaining Prosopium species is similar to distances between Stenodus and Coregonus. The small genetic distance between P. spilonotus and P. gemmifer suggests their recent divergence. Even though no fixed differences were found between them, diVerent alleles were present at two loci at large enough frequencies to indicate reproductive isolation. This confirms that P. gemmifer and P. spilonotus are good biological species as indicated by their distinct morphology and ecology. 相似文献
23.
In Argentina, five genera and 14 species are recorded in the subfamilies Prostemmatinae and Nabinae: Hoplistoscelis sordidus Reuter, Lasiomerus constrictus Champion, Metatropiphorus alvarengai Reuter, Nabis argentinus Meyer-Dür, Nabis (Tropiconabis) capsiformis Germar, Nabis faminei Stål, Nabis paranensis Harris, Nabis punctipennis Blanchard, Nabis roripes Stål, Nabis setricus Harris, Nabis tandilensis Berg, Pagasa (Pagasa) costalis Reuter, Pagasa (Lampropagasa) fuscipennis Reuter and Pagasa (Pagasa) signatipennis Reuter. 相似文献
24.
A new species of Nicon Kinberg, 1866 from the east Pacific coast of Ecuador is described. The new species is characterized by a long, thin dorsal ligule on median and posterior parapodia and infracicular sesquigomph falcigers in the neuropodia. A key to all species of Nicon is provided. 相似文献
25.
The cicada genus Nipponosemia Kato is reviewed. Four species are illustrated, photographed and described, including three known species and one new species. A key to all species of this genusis presented, and information on the biology of Nipponosemia are provided. The systematic status of the tribe Cicadatrini and biogeography of Nipponosemia are discussed. 相似文献
26.
JOSÉ ANTONIO FERNÁNDEZ PRIETO CARLOS AGUIAR EDUARDO DIAS MARÍA DE LOS ÁNGELES FERNÁNDEZ CASADO JUAN HOMET 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(3):522-533
The taxonomy and nomenclature of the genus Huperzia Bernh. in the Azores and Madeira have been reviewed. Plants collected in the Azores and Madeira were characterized morphologically. The independence between two endemic species common to Madeira and the Azores Islands –Huperzia suberecta (Lowe) Tardieu and Huperzia dentata (Herter) Holub – is clearly shown. A clear‐cut morphological separation between these taxa and Huperzia selago (L.) Bernh. ex Schrank & Mart. of continental Europe is established. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 522–533. 相似文献
27.
W. Kelley Thomas J. T. Vida Linda M. Frisse Manuel Mundo James G. Baldwin 《Journal of nematology》1997,29(3):250-254
To effectively integrate DNA sequence analysis and classical nematode taxonomy, we must be able to obtain DNA sequences from formalin-fixed specimens. Microdissected sections of nematodes were removed from specimens fixed in formalin, using standard protocols and without destroying morphological features. The fixed sections provided sufficient template for multiple polymerase chain reaction-based DNA sequence analyses. 相似文献
28.
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30.
GRECEBIO JONATHAN ALEJANDRO ULRICH MEVE SIGRID LIEDE‐SCHUMANN 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(1):87-92
Two new species of Mussaenda (Rubiaceae) from Aklan, Panay, Philippines are described and illustrated. Mussaenda ustii sp. nov. is distinct by its long pedicel (up to 7 mm), yellow with white margins corolla lobes forming a star and recurved stigma lobes which are always semi‐ or distinctly exserted in long‐styled morphs. Mussaenda viridiflora sp. nov. is characterized by its white, sweet‐scented corolla lobes, which are green tinged on the median ridges and bases, and strongly reflexed calyx lobes. A discussion of the relationships of the new taxa to closely related Philippine Mussaenda is provided. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 87–92. 相似文献