摘要:

In primary and secondary upland forests of Central Amazonia, Cryptocellus becki inhabits predominantly the organic layer of latosols (top 3.5 cm) whereas immatures of the smaller C. adisi live in the mineral subsoil as well (below 3.5 cm). C. adisi has hydrophobic navicular and calyx-like setae on its body and legs as well as alveolate, microtrichia-covered depressions on the cuticular surface. These plastron retaining structures, lacking in C. becki, apparently prevent C. adisi from getting wet during heavy rainfall and allow (facultative) plastron respiration if the mineral subsoil is temporarily inundated. Bristle-shaped microtrichia cover the elevated atrium wall of the spiracles in both species and these structures are shown for the first time by scanning electron micrographs.

ISSN:0165-0521    

DOI:10.1076/snfe.34.1.1.8915

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Rudra dagostinae sp.n. and Rudra brescoviti sp.n. from Brazil, are described as new species. Rudra dagostinae sp.n. e Rudra brescoviti sp.n. são descritas como novas para a fauna brasileira.

ISSN:0165-0521    

DOI:10.1076/snfe.34.1.10.8919

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Seven new species of Hydroptila (Trichoptera: Hydroptilidae) from Costa Rica are described: H. carara, H. maritza, H. osa, H. paradenza, H. maza, H. rastrilla, H. singri, and one from Panama, H. nusagandia. Ten additional species occurring in Costa Rica are recorded: H. brailovskyi Bueno-Soria, H. constricta Bueno-Soria, H. curvata Bueno-Soria, H. flinti Bueno-Soria, H. icona Mosely, H. meralda Mosely, H. mexicana Mosely, H. misolha Bueno-Soria, H. paschia Mosely, and H. veracruzensis Flint. In addition, illustrations of H. denza Ross and H. grenadensis Flint are included to help clarify the taxonomy of the denza species group. Finally, an illustrated key is provided for males of all species occurring in lower Central America.

ISSN:0165-0521    

DOI:10.1076/snfe.34.1.16.8916

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Samples of benthic oligochaetes were collected from March 1993 to February 1994 in channels of the Paraná river. 14 species were identified for which the average density was determined at five sites representing different environmental conditions. Principal component analysis showed strong correlation in occurrence with granulometric texture and organic matter in the sediment of the dominant species Narapa bonettoi as well as of Haplotaxis aedeochaeta, Limnodrilus hoffmeisteri and Pristina americana. The results are discussed in relation to sampling site factors like sediment structure and seasonal changes in water level.

ISSN:0165-0521    

DOI:10.1076/snfe.34.1.52.8917

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

At six different forest sites in Venezuela, we estimated the diversity and abundance of ants and nymphalid butterflies on the ground and in the canopy, and of plants. Statistical analysis using eight different diversity indices for each species group revealed large variations among them. Ground ants appeared to be the most reliable bioindicators, even when only the five most common species are considered. Results showed in addition that ground ant diversity is correlated to that of canopy ants and that vegetational diversity is linked to butterfly diversity but not to that of canopy ants. Ant species diversity in the canopy was always less than that on the ground. We conclude that no simple index or single taxon describes completely complex ecosystems, thus, biodiversity assessments require tools still to be developed.

ISSN:0165-0521    

DOI:10.1076/snfe.34.1.59.8918

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor