摘要:

Distribution patterns in the larvae of two chironomid species with contrasting ecological traits,Ckironomus anthracinusZetterstedt andProcladius signatus(Zetterstedt), were examined by taking replicate samples from Lough Neagh, Northern Ireland. The two species showed clear differences in both vertical and horizontal distributions. In terms of vertical distributionP. signatuslarvae were restricted to the top 3 cm layer of sediment, while C.anthracinuslarvae were most abundant in the 3–9 cm layer. Larvae rarely occurred below 12 cm of the sediment surface. In terms of horizontal distribution the two species departed significantly from random distribution, though the patterns of dispersion were different between the two.P. signatusdemonstrated a more strongly aggregated pattern thanC. anthracinus.The latter species showed a tendency towards a regular distribution, which may be related to its sedentary, territorial habit. Observed differences in spatial distribution between these two species may be typical of herbivorous vs. omnivorous/carnivorous species of chironomid inhabiting lake sediments.

ISSN:0165-0424    

DOI:10.1080/01650429409361546

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A new genus of baetid mayflies is described, the adults closely related to the carnivorous genusCentroptiloidesbut the nymphs with mandibles of the ancestral grinding type. Two species formerly includedin Afroptilumare transferred toDicentroptilum, A. decipiensandA. spinulosum.A new species from West Africa is described here.

ISSN:0165-0424    

DOI:10.1080/01650429409361547

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Neotelmatoscopus ctenophorusa remarkable new non‐Phlebotomine psychodid collected from the Kolli hills, Salem District, Tamil Nadu, India is described. A key is provided to the known species ofNeotelmatoscopus

ISSN:0165-0424    

DOI:10.1080/01650429409361548

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Descriptions of the hitherto unknown second instar larva ofSisyra fuscata(Fabricius, 1793) and of the first to third instar larva and pupa ofSisyra terminalisCurtis, 1854 are presented. The most important diagnostic features are illustrated, and some taxonomic, zoogeographical and ecological notes are included.

ISSN:0165-0424    

DOI:10.1080/01650429409361549

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Selected internal and external structures of the head of larvae ofHydrotrupes palpalisSharp are examined, described and interpreted phylogenetically. The results suggest a sistergroup relationship betweenHydrotrupesand the remaining Dytiscidae excl. Copelatini. Therefore,Hydrotrupesshould be excluded from Colymbetinae. The sistergroup relationship between Copelatini and all other Dytiscidae is confirmed.

ISSN:0165-0424    

DOI:10.1080/01650429409361550

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The South African speciesCloeodes inzingae(Crass) is redescribed as adults and larvae based on newly found material. This species is most closely related to far eastern Palaearctic (China) and Oriental (Sri Lanka) species rather than Neotropical species. The presence ofCloeodesin the Subsaharan region of Africa supports the opinion that it is basically a pantropical genus.Cloeodes inzingaepossesses a median tubercle between the forceps bases, a character not known in any otherCloeodes.

ISSN:0165-0424    

DOI:10.1080/01650429409361551

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

Two species ofAnacroneuriaoccur on the islands of Trinidad and Tobago. A.aroucanaKimmins, 1948, appears to be endemic to Trinidad whileA. isletasp. n., occurs on Tobago. BothA. isletaandA. aroucanaappear to have sister species on the South American mainland.

ISSN:0165-0424    

DOI:10.1080/01650429409361552

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The psychomyiid caddis flyTinodes waeneri(L.) mated on a shrub near the shore‐line (and the littoral emergence site) and on adjacent flowers. Both males and females were shown to ingest nectar, from different species of flowers having open nectaries (mostly of the family Apiaceae). Male fat content was negatively correlated with age (wing wear), indicating that ingested nectar did not restore lipids. Therefore, we presume that nectar was mainly used for mechanical activities (e. g. flying, walking, mating). A male lost about 7% of his original carbon and nitrogen during copulation, suggesting that they had the potential to copulate often. The sex ratio differed between the shrub and flower habitats, and females on flowers were also older and had more frequently laid eggs. Thus, females seemed to mate as virgins on the shrub, deposited their first egg batch, returned to the shore, ingested nectar from the flowers and copulated again. Males on flowers encountered proportionally more females, but those females contained on average only 3% of the number of eggs compared with females on the shrub.

ISSN:0165-0424    

DOI:10.1080/01650429409361553

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

ISSN:0165-0424    

DOI:10.1080/01650429409361545

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor