摘要:

Ecdyonurus moreaesp.n. is described from Peloponnese, Southern Greece. Diagnostic characters are: stout and rounded penis lobes, oblique stripes on the sides of abdomen, and abdominal ganglia pigmented. 12 further taxa from Greece are listed and briefly discussed: 3 species are new for Greece.

ISSN:0165-0424    

DOI:10.1080/01650428609361253

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The genusPseudocentroptiloidesJacob is proposed forPseudocentroptilum(?) shadini Kazlauskas (NE‐Europe), the only species of the subgenusPseudocentroptiloidess. str. The subgenusPsammonellaGlazaczow is proposed for a new species from Sri Lanka,Pseudocentroptiloides (Psammonella) ceylonicaGlazaczow. The two subgenera agree in a number of apotypic character states but differ in the presence (Pseudocentroptiloidess.str.) or absence (Psammonella) of hindwings. The authors feel that the latter character is of subordinate importance but has in some cases been over‐emphasised by other authors. There appears to be a general risk that phyletic affinities between members of the Baetidae are obscured by assigning generic status to the most apotypic members of a given mono‐phyletic group.

ISSN:0165-0424    

DOI:10.1080/01650428609361254

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The life cycles of the burrowing mayflies,Ephemera strigataEaton andE. japonicaMcLach‐lan were studied comparatively between upper part and lower part of a small tributary of the Yoshino River.E. strigatawas more common thanE. japonicain the studies areas.E. japonicawas found only in the upper part and in tiny tributaries of the stream.E. strigatawas univoltine in the lower and in the upper parts of the stream. However, the population falls into two groups, one of which emerges in early May and the other in summer. Water temperature seems to be one of the factors affecting the variable life cycle ofE. strigata. E. japonicais univoltine. Emergence of this species was observed from June to August.

ISSN:0165-0424    

DOI:10.1080/01650428609361255

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The immature stages and adult female ofUnniella multivirgaSaether are described for the first time. The systematic position of the genus is discussed. The genus appears to belong in theRheocricotopus, Nanocladius, Doncricotopus, Mesocricotopus, Psectrocladius, andParacricotopusgroup of genera.

ISSN:0165-0424    

DOI:10.1080/01650428609361256

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Field studies ofNemoura arcticaandN. vikishowed that the two species preferred different biotopes and indicated differences in their life‐cycles.N. arcticaseemed to have a semivoltine life‐cycle, at least in some years, this was not the case forN. viki.

ISSN:0165-0424    

DOI:10.1080/01650428609361257

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Stonefly density, biomass, size and diversity relationships with CPOM and FPOM were elucidated from 12 months of Surber sampling in a riffle of a 2nd order, northeastern Oklahoma stream in 1983–84. Samples taken across an observable gradient of allochthonous leaf material resulted in clumped CPOM distributions in monthly samples (n = 10)for 10 of 12 months. FPOM was regularly distributed among monthly samples. There was an inverse relationship between CPOM an d FPOM for most months suggesting substratu m interaction in organic matter retention. Mean annual density of 8 stonefly species was 113 ± 150/0.1 m2. Nymphs were found in clumped distributions for 11 of 12 months (p < 0.05). Density, biomass and diversity were positively correlated to CPOM annually. Autecolo‐gical analysis of 8 species showed varying degrees of association with CPOM and/or FPOM, suggesting specific habitat preference, ontogenetic shifts, or possible biotic interaction. Density and biomass of 4 species was related to CPOM (Acroneuria evoluta, predator;Isoperla namata, generalist;Amphinemura delosaandProstoia completa, shredders). These species contributed 72.5% of the total stonefly biomass sampled (13.39 gm. dry wt.). CPOM provides both food and habitat for stoneflies, and is therefore important in their community structure and function.

ISSN:0165-0424    

DOI:10.1080/01650428609361258

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Larvae of the blackflySimulium noelleriFriederichs aggregate at high populatio n densities on dams and spillways at the outlet of ponds. When displaced into the water column from their point of attachment, larvae can secrete silk threads as "life-lines" which enable them to maintain a link to the substratum an d up which they can climb to regain their original position. Experiments were conducted in a laboratory pond outlet to investigate this use of silk threads, larvae being displaced by means of forceps. It was demonstrated that: (i) the length of thread produced , and the speed of climbing the thread are independent of larval size; (ii) within limits, the speed of climbing was independent of both the length of the thread and the time already spent climbing, and (iii) speed of climb became more rapid as larvae neared the point of attachment. The range of locomotion in blackfly larvae is then discussed.

ISSN:0165-0424    

DOI:10.1080/01650428609361259

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0165-0424    

DOI:10.1080/01650428609361252

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor