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241.
242.
Dolichodorus cobbi n. sp. is described and illustrated from soil around roots of "woods" on the Stanley Farm, Scott County, Arkansas. This species is distinguishable from others of the genus by its short tail projection. It is most closely related to D. marylandicus but differs in having a short tail projection, longer stylet, greater body length, larger c value, and also in position of excretory pore. A limited number of Cobb''s original specimens and drawings of D. heterocephalus were examined. A lectotype and paralectotype were designated to establish the taxonomic base for the genus. Cobb''s original modified labeled drawing of D. heterocephalus is also included. Morphometric data on D. heterocephalus from the type locality and several other populations are given. Some variations in female tail shape, body length, and stylet length were noted. 相似文献
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In The Netherlands the decline of some phanerogamic species cannot be readily explained from obvious factors such as lowering of the groundwater table, eutrophication or land reclamation. For a number of species the hypothesis was tested that the decline is partly due to air pollution. A two-factor model was made in which decline is accounted for by (a) habitat destruction assessed from topographic maps and (b) air pollution measured as the SO2 95-percentile over the winter period 1978/1979. Effects of both factors were assumed to follow a sigmoid dose-effect curve. For a number of species decline proved to be significantly correlated with air pollution. These are notably species from the syntaxon Violion caninae. A comparison was made with results obtained for epiphytic lichens. It appears that for some phanerogamic species sensitivity is about the same as for moderately sensitive lichens.Nomenclature follows Heukels & van der Meijden (1983).Thanks are due to the Rijksherbarium, for providing some of their unpublished data; and to Ada Groeneveld, for technical assistance. 相似文献
248.
RAY GIBSON 《Zoological Journal of the Linnean Society》1985,83(2):95-227
Twenty-three species representative of 15 heteronemertean genera are recorded from Antarctic and Subantarctic waters south oflatitude 50o S. Five new genera are established and seven new species are fully described and illustrated. These are Cephalurichus antarcticus gen. et sp. nov., Dokonemertes magellanensis gen. et sp. nov., Dokonemertes macquariensis sp. nov., Micrellides multiperula gen. et sp. nov., Paramicrurinella falklandica gen. et sp. nov., Parborlasia landrumae sp. nov. and Zodionemertes chilensis gen. et sp. nov. Baseodiscus antarcticus Baylis, Antarctolineus scotti (Baylis), Lineus longifissus (Hubrecht) and Parborlasia fueguina Serna de Esteban & Moretto are redescribed and illustrated and the nature of rhynchodaeal pouches protruding into the cephalic blood lacunae of Parborlasia corrugatus (Mcintosh) is reexamined and discussed. The main anatomical characters of the remaining 11 species are recorded and it is concluded that of these only Parapolia grytvikenensis Wheeler, Cerebratulus malvini Wheeler, Chilineus glandulosa (Burger), Huilkia ushuaiensis Serna de Esteban & Moretto, Micrura pacifica Friedrich and Wiolkenia friedrichi Serna de Esteban & Moretto can at present be accepted as valid, although incompletely described, taxa. Cerebratulus larseni Wheeler, Cerebratulus validus Bürger, Lineus autrani Joubin and Lineus turqueli Joubin are so poorly and inadequately described that their taxonomic status cannot be verified, and the recorded occurrence of Lineus nigricans Burger in southern latitudes cannot be substantiated on the available evidence. Maps showing the recorded distribution of all the species are included and a key to the 18 validated species is provided. 相似文献
249.
DAVID HOLLIS 《Zoological Journal of the Linnean Society》1985,83(4):325-342
The genus Parapsylla (Homoptera: Psylloidea) is redescribed and placed in the Diaphorininae of the Family Aphalaridae. Its relationships within this subfamily are discussed. The genus Agmapsylla syn. nov. is placed into the synonymy of Parapsylla , and Pennavena syn. nov. and Eudiaphorina syn. nov. are placed into the synonymy of Diaphorina. The eight known species of Parapsylla are distributed in southern Africa and upland areas of East Africa. Host plant relationships are not clearly established but the genus appears to be associated with species of Maytenus (Celastraceae), Olinia (Oliniaceae) and possibly Olea (Oleaceae) and Syzygium (Myrtaceae). Parapsylla relicta syn. nov, and A. aureus syn. nov. are placed into the synonymy of Arytaina capensis. Parapsylla capensis comb. nov. is transferred from Arytaina, Parapsylla valens comb. nov. is transferred from Diaphorina , and the following new species are described: P. angolensis sp. nov., P. eafra sp. nov., P. huila sp. nov., P. marginipennis sp. nov., P. rufa sp. nov. and P. theroni sp. nov. 相似文献
250.