Feeding ecology of Apocyclops procerus (Copepoda, Cyclopoida) under experimental conditions

Copepods are key links between primary producers and higher pelagics. We investigated, for the first time, under laboratory conditions, some aspects of the reproductive behaviour and feeding preferences of Apocyclops procerus (Copepoda: Cyclopoida) under different conditions of salinity and food supply. This is also its first record for Pernambuco (NE Brazil). The females carry their eggs until their eclosion and present several cycles of egg production without being further fecundated. Egg production and adult life span were not affected by differences in salinity or food supply. Offspring predation was also observed. From the three microalgae species offered to A. procerus individuals, Thalassiosira weissflogii, Chaetoceros muelleri (Ochrophyta) and Isochrysis galbana (Haptophyta), the small round-shaped I. galbana was preferred over the large and spiny diatoms, in spite of its lower nutritional value. The high salinity tolerance and apparently omnivorous feeding habits of A. procerus may enable it to predominate in estuarine waters.

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Diet influence on egg production of the copepod Acartia tonsa (Dana, 1896)

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652010000200009 ◽

2010 ◽

Vol 82 (2) ◽

pp. 333-339 ◽

Cited By ~ 15

Author(s):

Priscila F. Teixeira ◽

Sonia M. Kaminski ◽

Tatiana R. Avila ◽

Alessandro P. Cardozo ◽

José G.F. Bersano ◽

...

Keyword(s):

Egg Production ◽

Isochrysis Galbana ◽

Threshold Value ◽

Acartia Tonsa ◽

Thalassiosira Weissflogii ◽

Chaetoceros Muelleri ◽

Experimental Conditions ◽

Male And Female ◽

Experimental Medium ◽

Controlled Conditions

Egg production in the copepod Acartia tonsa was evaluated using different densities of the microalgae Thalassiosira weissflogii, Chaetoceros muelleri and Isochrysis galbana. Male and female were kept under controlled conditions (salinity 30, 20°C, photoperiod 12L:12D), acclimated to the experimental conditions and left over a period of 24 h to allow copulation. Algal densities tested were equivalent in biovolume and corresponded to 0, 2.5, 5, 10, 20, 40 and 60.10³ cells.mL-1 of T weissflogii. Ten acclimated female were separated, transferred to glass bottles and exposed for further 24 h to the corresponding experimental medium. After this period, the eggs were fixed and counted. Copepod egg production reached a threshold value when T weissflogii, C. muelleri and I. galbana were supplied at 10.10³, 140.10³ and 640.10³ cells.mL-1, respectively. Mean egg production corresponded to 28.0 ± 0.5, 20.1 ± 1.0 and 22.0 ± 3.5 eggs.female-1 .day-1, respectively. Copepods fed T weissflogii showed the highest mean egg production while those fed I. galbana reached a maximum egg production when the algae were supplied at a density two- to fourfold higher, considering the biovolume of T weissflogii and C. muelleri. These differences are explained considering the different sizes of the microalgae used to feed the copepods.

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The impact of Arrenurus danbyensis Mullen (Acari: Prostigmata; Arrenuridae) on a population of Coquillettidia perturbans (Walker) (Diptera: Culicidae)

Canadian Journal of Zoology ◽

10.1139/z84-163 ◽

1984 ◽

Vol 62 (6) ◽

pp. 1121-1134 ◽

Cited By ~ 24

Author(s):

Bruce P. Smith ◽

Susan B. McIver

Keyword(s):

Egg Production ◽

Negative Binomial ◽

Natural Populations ◽

Adult Life ◽

Published Data ◽

Adult Life Span ◽

Coquillettidia Perturbans ◽

Host Seeking ◽

Parasitic Mites ◽

The Impact

Adult Coquillettidia perturbons (Walker) collected in Algonquin Park, Ontario, Canada, from 1978 to 1980 were parasitized by larval Arrenurus danbyensis Mullen. Up to 87.5% of newly emerged mosquitoes were parasitized. The prevalence of parasites on host-seeking mosquitoes rarely exceeded 30%. This discrepancy is not the result of mites dropping off host-seeking mosquitoes. By comparing pairs of samples over the apparent interval of 1 – 2 days between emergence and host-seeking, it is estimated that 42.5% of the newly emerged were not recruited to the host-seeking population. In the laboratory, no significant effect of parasitic mites on the host's adult life-span or blood-meal size was detected, but there was a significant effect on the host's egg production. The distribution of mites on mosquitoes was characterized by combining the Taylor power law and the negative binomial distribution. With this relationship, the effect of mite parasitism on the host's egg production in the laboratory could be extrapolated to estimate this effect on natural populations. In the population studied, egg production is reduced by approximately 5%. Based on published data, egg production in the first gonotrophic cycle of a population of Anopheles crucians Wiedemann is reduced by up to 35%.

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Egg Production and Adult Life Span in Two Species of Bracon (Hymenoptera: Braconidae)1

Annals of the Entomological Society of America ◽

10.1093/aesa/60.5.903 ◽

1967 ◽

Vol 60 (5) ◽

pp. 903-905 ◽

Cited By ~ 8

Author(s):

Arnold M. Clark ◽

Robert E. Smith

Keyword(s):

Life Span ◽

Egg Production ◽

Adult Life ◽

Adult Life Span

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THE BIOLOGY OF CEPHALONOMIA WATERSTONI GAHAN

Canadian Journal of Research ◽

10.1139/cjr49d-011 ◽

1949 ◽

Vol 27d (3) ◽

pp. 93-111 ◽

Cited By ~ 12

Author(s):

R. Omar Rilett

Keyword(s):

Biological Control ◽

Adult Life ◽

Experimental Conditions ◽

Adult Life Span ◽

Control Programs ◽

Morphological Studies ◽

Large Numbers ◽

Hymenopterous Parasite ◽

Brownish Black ◽

Whole Life Cycle

Life history and morphological studies were made on Cephalonomia waterstoni Gahan, a hymenopterous parasite on the larval and pupal stages of the rusty grain beetle, Laemophloeus ferrugineus (Steph.). At 90° F. and 65 to 75% relative humidity the whole life cycle of C. waterstoni is completed within 12 to 13 days. The adult life span of females is about three weeks, while that of males is much shorter. The male, which prior to this work was unknown, can easily be distinguished from the female by its smaller size, its less rectangular-shaped head, and its longer antennae. The first flagellar segments of the males are brownish-black in color while those of the females are yellowish. The ratio of females to males is somewhere near 2:1. The ease with which the parasite C. waterstoni can be reared in large numbers in the laboratory, and its remarkable ability to check infestations of L. ferrugineus under experimental conditions, indicate that this species might be of value in biological control programs for L. ferrugineus in warehouses, mills, and elevators.

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Interactions between the scelionid egg parasitoid Tiphodytes gerriphagus (Hymenoptera) and its gerrid hosts (Heteroptera)

Canadian Journal of Zoology ◽

10.1139/z86-397 ◽

1986 ◽

Vol 64 (12) ◽

pp. 2728-2738 ◽

Cited By ~ 24

Author(s):

John R. Spence

Keyword(s):

Egg Production ◽

Adult Life ◽

Late Summer ◽

Egg Parasitoid ◽

The Body ◽

Host Size ◽

Lower Growth ◽

Adult Life Span ◽

Jelly Coat ◽

Parasitoid Population

Tiphodytes gerriphagus parasitized eggs of five Gerris and two Limnoporus species in the laboratory and the parasitoids were reared from field-collected eggs of G. buenoi, G. comatus, G. pingreensis, L. dissortis, and L. notabilis. Eggs of G. buenoi and L. dissortis were parasitized over about 80% of development. Wasps preferred eggs of G. buenoi over those of L. dissortis, which were larger but covered by a jelly coat. However, under field conditions, eggs of L. dissortis laid at the water surface were parasitized more than submersed eggs of Gerris species. Host size (= species) had no apparent effect on adult life-span but affected the body length of adult parasitoids. Size of females was affected more than that of males and lifetime fecudity also varied with host size. Parasitoids laid most of their eggs during the first 4 days after emergence, averaging 8–11 parasitized hosts per day. Tiphodytes gerriphagus was reared from eggs of Limnoporus collected throughout western Canada. Rates of parasitism peaked just after egg production by L. dissortis, suggesting selection for early oviposition by gerrids. Most Limnoporus populations were heavily parasitized by late summer, but in some temporary or newly created habitats, rates of parasitism were lower. Growth of the parasitoid population at a new habitat was slower than at nearby ponds with large resident wasp and gerrid populations, and the lower parasitoid abundance was associated with greater production of L. dissortis. Adults of T. gerriphagus appear to overwinter in gerrid eggs at the bottom of ponds. At temporary sites, wasps may fail to survive the winter and recolonize more slowly than Limnoporus. Interaction with parasitoids may explain the patchy nature of L. dissortis distribution and its restriction to temporary habitats. Presence of T. gerriphagus may also affect the outcome of competitive interactions among gerrid species.

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