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61.
62.
M. Alonso 《Hydrobiologia》1984,118(2):135-146
The distribution of the Calanoid genus Mixodiaptomus was studied in a large number of pools and small lakes scattered over Spain. Four species occur: M. incrassatus, M. kupelwieseri, M. ortizi and M. laciniatus, the latter in 2 subspecies (M. laciniatus laciniatus and M. laciniatus atlantis). M. ortizi is described as a new species. M. laciniatus lives in mountains, while all other species occur in the plains. M. incrassatus is found all over the country, M. kupelwieseri only in the eastern part of Catalonia, M. laciniatus atlantis in Andalucia and M. ortizi in the central lands called Mesetas. All live in little mineralized waters and only M. incrassatus and M. laciniatus atlantis occur in clayey waters. 相似文献
63.
64.
Twenty species of Cladocera are reported from the Nile, where lacustrine species dominate, and from Jebel Marra and the Red Sea Hills, where chydorids dominate. The community found in the Red Sea Hills is more typically desertic than that of Jebel Marra, which appears closely related to the fauna of the West and Central African Sahel. 相似文献
65.
66.
Fifteen species of fiddler crabs are reported for eastern North America between Massachusetts and Quintana Roo, Mexico. Thirteen occur in the United States and 11 in Mexico, with eight in common to the two countries. Of 13 species in the Gulf of Mexico, five are endemic and a sixth is restricted largely to the peninsulas of Florida and Yucatan. The status of U. rapax in the northern Gulf remains to be resolved. Range limits of most species approximate one or the other of two sets of intersecting thermal and geological boundaries that subdivide the Gulf of Mexico along north-south and east-west axes. Species belonging to subgenus Minuca tend to replace one another at the thermally-controlled Carolinian-Caribbean marine biotic boundary across the Florida peninsula and northern Gulf. However, only U. minax of all the North American fiddler crabs exhibits the classical disjunct Carolinian distribution, and this appears basically to reflect the discontinuous distribution of temperate salt marshes that are the habitat of the species. Distributions of species belonging to subgenus Celuca adhere for the most part to the subdivision of the Gulf into western terrigenous and eastern carbonate sedimentary provinces. The northern transition occurs in the vicinity of Apalachee Bay and the southern at Laguna de Terminos. A third distributional pattern is shown by U. subcylindrica , a specialized endemic species of the hypersaline Laguna Madre system of the western Gulf. The level of endemism in the fiddler crabs is relatively high in comparison with that of other marine groups within the Gulf of Mexico. This may be a consequence of the adaptations of fiddler crabs as specialized deposit feeders to regional differences in climatic and edaphic characteristics of a marginally marine upper shore habitat. The distributional patterns of the endemics could prove useful in reconstructing palaeoecological events of evolutionary significance within the Gulf of Mexico. 相似文献
67.
Two new monosexual and one bisexual species Pratylenchus Filipjev, 1936 collected from Haryana state of India are described and illustrated. The primary distinguishing features of these species are Pratylenchus microstylus n. sp.: L = 331-458 μm, spear = 11 or 12 μm; Pratylenchus cruciferus n. sp.: L = 648-793 μm, central core of lateral fields with oblique lines, hemizonid 2-8 annules anterior to excretory pore; Pratylenchus ekrami n. sp.: spear = 11-13 μm, spermatheca oblong, post vulval uterine sac with differentiated cells, tail with 26-40 annules, males abundant. Studies on intraspecific variations of P. cruciferus, P. ekrami, and P. coffeae (Zimmermann, 1898) Goodey, 1951 revealed that spear length and value of ''V'' are the least variable characters. Body length and size of post vulval uterine sac varies to varying degrees in different species. Shape of median bulb in P. ekrami, number of incisures in P. coffeae, and tail shape in P. ekrami and P. coffeae exhibit the greatest amount of intraspecific variations. P. zeae Graham, 1936 and P. thornei Sher & Allen, 1953 are the other species collected during the present studies. 相似文献
68.
A nematological survey of Belgium revealed four species of Aphanolaimus, two known ones, A. attentus de Man, 1880 and A. aquaticus Daday, 1894, and two new ones. A. pseudoattentus n.sp. resembles A. attentus in many respects but can easily be distinguished by the greater body length, the head shape, the shape of the amphideal fovea
and the longer cephalic setae. A. deconincki n.sp. is characterized by its head shape, shape of amphideal fovea, posterior origin of lateral field and large number of
body annules. 相似文献
69.
Heterodera zeae, the corn cyst nematode, is redescribed and illustrated with comparative details and measurements of females, cysts, and larvae from Maryland, USA; and India. Scanning electron micrographs o f specimens from the United States are also presented. Revised measurements for the larval stylet and new diadnostic characters, especially in the cyst cone, for H. zeae are given. The relationship of H. zeae to close species is discussed. 相似文献
70.
Thecavermiculatus andinus n.sp. is described and illustrated from Oxalis tuberosa originally collected in the vicinity of Lake Titicaca high in the Andes mountains of southern Peru. This new species differs markedly front the other two species in the genus, especially in having a much greater female vulval-anal distance and annules with lined punctation on most of the female body with a lacelike pattern restricted to the posterior portion, particularly at the vulva and anus which do not protrude. Females are essentially spherical with protruding neck, white to yellowish in color, and can easily be mistaken for potato cyst nematodes. Among the dozen or more known weed and crop host plants are potato and eggplant. In order to accommodate this new species, the genus Thecavermieulatus is emended. A key to the species of this genus is presented. 相似文献