摘要:

The egg size and the external egg morphology in fourteen species of anostracans were described. In the Branchinectidae species studied two basic patterns in the external layer were distinguished. In Thamnocephalidae:Dendrocepha‐lus cervicornisandD. brasiliensisdiffer in the shape of cells, size, length and thickness of the ridges. In Chirocephalidae:Phallocryptus salinicoladiffers from other genera. The combined analysis of the diameter and the morphology of the outer covering constitutes a very useful methodology for the determination of genera and species. Using the mentioned characteristics it has been possible to elaborate a key for the identification of these species.

ISSN:0165-0521    

DOI:10.1080/01650528909360788

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Using materials of collection from nearly all the Argentinian provinces, a map of the distribution of the anostracans in Argentina has been elaborated. From the eight families recognized on a world scale, four are represented in the country; being the best represented considering the number of the species is the Branchinectidae one. New localities are mentioned forBranchinecta rocaen‐sis, Dendrocephalus cervicornis, D. brasiliensis, Phallocryptus salinicolaandAnemia salina.

ISSN:0165-0521    

DOI:10.1080/01650528909360789

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Adult males and females ofPolymorphus (Profilicollis) chasmagnathicomb, nov. are described with comments on this species’ definite natural host.

ISSN:0165-0521    

DOI:10.1080/01650528909360790

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

About 74,000 arthropods per m2soil were extracted in a dryland forest on white sand soil (campinarana) near Manaus, Brazil, during the rainy season in early 1986. About 58% of all arthropods lived in the top 3.5 cm, 16% underneath (3,5–7 cm depth), and only 6% in 7–14 cm depth. Acari and Collembola represented nearly 80% of the total catch. Disregarding these two orders, Formi‐cidae, Pauropoda, Diplura and Protura amounted to more than 50% of the total catch. Decreasing arthropod abundance with greater soil depth corresponded with data already known from other neotropical dryland forests, but was not significantly correlated with increasing soil humidity. No indication is found yet that arthropods of Central Amazonian dryland forests migrate to the mineral subsoil as a response to changing abiotic factors in the organic layer due to seasons, as reported from forests in the seasonal tropics.

ISSN:0165-0521    

DOI:10.1080/01650528909360791

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

About 58,000 arthropods per m2soil were extracted in a dryland forest on white sand soil (campinarana) near Manaus, Brazil, during the dry season in mid 1988. About 63% of all arthropods lived in the top 3.5 cm, 21% underneath (3.5–7 cm depth), and only 16% in 7–14 cm depth. Acari and Collembola represented more than 75% of the total catch. Decreasing abundance was significantly correlated with lower soil temperature and lower soil humidity at greater soil depth. Vertical distribution of arthropods corresponded with data obtained during the rainy season in early 1988 from the same forest and with results already known from other neotropical dryland forests. No indication is found yet that arthropods of Central Amazonian dryland forests migrate to the subsoil as a response to changing abiotic factors in the upper layer due to seasons, as reported from forests in the seasonal tropics.

ISSN:0165-0521    

DOI:10.1080/01650528909360792

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The stingless beeMourella caeruleais distributed in the subtropical parts of Brazil, Argentina and Paraguai. In the Serra do Sudeste of Rio Grande do Sul, on the southern part of the Brazilian shield, this species is one of the most abundant meliponine bees. Nests ofM. caeruleaare built in the soil and exhibit architectural characters typical to all other genera of obligatory ground nesting species, likeSchwarziana, and the African generaMeliple‐beia, PlebeiellaandPlebeina. The possibility that the similar solutions for the construction of subterranean nests in these genera did not evolve by convergence or parallelism is discussed. The occurence ofMourellatogether with other more primitive representatives of thePlebeiagroup on the southern parts of the Brazilian Shield cannot be explained by biogeographic models proposed by some authors. Adopting an alternative model we suggest that, during the lower Cretaceous, ancestor populations of thePleibeia‐line inhabiting the meridional shields of Western Gondwanaland (now southern Brazil and southern Africa), were separated by the south‐northward opening of the South Atlantic. During the Cretaceous until the lower Tertiary the remnant populations on the southern parts of the Brazilian shield were isolated by the immense basalt flows and subsequent volcanic Tertiary activity bordering this area. During their dispersal in the Tertiary species ofPlebeia(s. str.; post Gondwanic derived forms) may have radiated via the Patagonian shields and their terrestrial connections to Antarctica and from there to Australia, while otherPlebeia(s. str.) species dispersed into the northern parts of South America. The monotypic generaMourellaandSchwarzianaand most of the more primitive species ofPlebeia(s. str.), however, remained restricted to their presumable subtropical centers of origin.

ISSN:0165-0521    

DOI:10.1080/01650528909360793

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Twelve species of the families Siphonolaimidae and Linhomoeidae are presented from various habitats of Deseado River estuary. Six species are new to science:Siphonolaimus mejillinussp. nov.,Terschellingia sulfidricasp. nov.,Metalinhomoeus gloriaesp. nov.,Metalinhomoeus parafiliformissp. nov.,Paralinhomoeus visitussp. nov. andParalinhomoeus aridussp. nov. Another six well known species are reported from Argentine coasts for the first time.

ISSN:0165-0521    

DOI:10.1080/01650528909360794

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Observations during the past 15 years on mountain stream breeding frogs in the Atlantic Mountains around Santa Teresa in the State of Espirito Santo, Brazil, indicate that some species, in particular the Hylodinae andCycloramphus fuliginosus, have disappeared after 1981. The most likely causes for these extinctions were some extremely dry winters. However, similar extinctions reported by Heyer et al. (1988) from the states of Rio de Janeiro and São Paulo suggest that there might be an unknown common underlying cause, and the acidity of the stream water makes acid rain one of the possible causes.

ISSN:0165-0521    

DOI:10.1080/01650528909360795

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

ISSN:0165-0521    

DOI:10.1080/01650528909360787

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor