Self-sustaining infrapopulation or colony? Redial clonal groups of Himasthla elongata (Mehlis, 1831) (Trematoda: Echinostomatidae) in Littorina littorea (Linnaeus) (Gastropoda: Littorinidae) do not support the concept of eusocial colonies in trematodes

Title:

Self-sustaining infrapopulation or colony? Redial clonal groups of Himasthla elongata (Mehlis, 1831) (Trematoda: Echinostomatidae) in Littorina littorea (Linnaeus) (Gastropoda: Littorinidae) do not support the concept of eusocial colonies in trematodes

Creator:

Kirill Vladimirovič Galaktionov, Podvyaznaya, Irina M, Nikolaev, Kirill E, and Levakin, Ivan A

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:5f33a11d-5876-444a-abcf-6ffa5f6d0f3d
uuid:5f33a11d-5876-444a-abcf-6ffa5f6d0f3d
issn:1803-6465
doi:10.14411/fp.2015.067

Subject:

kasty, rozmnožování (biologie), castes, reproduction, rediae, parthenitae, Digenea, eusociality, germinal mass, allometry, developmental arrest, feeding behaviour, 2, and 59

Type:

model:article and TEXT

Format:

print, počítač, and online zdroj

Description:

Trematode sporocysts and rediae reproduce by parthenogenesis, forming clonal groups in the molluscan host. It has recently become popular to consider these groups as eusocial colonies, with division of labour between rediae morphs: small 'soldiers' incapable of reproduction defend the colony, while large rediae reproduce. Alternatively, clonal groups can be considered as self-sustaining infrapopulations. We tested these two hypotheses in the light of new data on rediae of Himasthla elongata (Mehlis, 1831) from snails Littorina littorea (Linnaeus) concerning ultrastructure, growth character and composition of their groups. Clonal groups under study contained rediae of different age and maturity stages: small (young) rediae, rediae with early cercarial embryos, rediae with late embryonic cercariae, rediae with fully formed motile cercariae, rediae with redial embryos and degenerating rediae. Small rediae had a reproductive organ, the germinal mass, whereas most large rediae with developing cercariae did not, which contradicts the eusocialconcept. Overall distribution of rediae by size and by gut to body length ratio was bimodal, which agrees with the eusocial concept ('soldiers' and 'reproductives' as modal size classes). On closer inspection, however, the bimodal size-frequency distributions (SFD) turned out to be the sum of unimodal SFD of rediae at various stages of maturity. The overall bimodality was determined by the character of redial growth resulting in a relatively low occurrence of intermediate morphs and by the developmental arrest in young rediae. The facts that small rediae can attack other rediae and concentrate in the anterior parts of the mollusc can be explained by age-related feeding preferences and niche segregation. They are unlikely to be associated with the 'colony' defence against invaders. To sum up, clonal groups of H. elongata rediae in our study represented self-sustaining infrapopulations., Kirill V. Galaktionov, Irina M. Podvyaznaya, Kirill E. Nikolaev, Ivan A. Levakin., and Obsahuje bibliografii

Language:

English

Rights:

http://creativecommons.org/publicdomain/mark/1.0/
policy:public

Coverage:

1-14

Source:

Folia parasitologica | 2015 Volume:62 | Number:1

Harvested from:

CDK

Metadata only:

false