Electra vs Callopora

Author(s)
Ekaterina Shevchenko, Marina Varfolomeeva, Uliana Nekliudova, Olga N. Kotenko, Nikolay Usov, Andrei Granovitch, Andrew Ostrovsky
Abstract

The life histories of two common boreal-Arctic bryozoans – Electra pilosa and Callopora craticula living on kelps in the White Sea are described for the first time using colony mapping. Colony functional dynamics (sexual, feeding, budding and rejuvenation) was traced seasonally via recording zooidal states. During the ice-free season the population of the zygote spawner E. pilosa was represented by
three generations – overwintered (maternal) and two young ones (daughter and granddaughter). The overwintered colonies exhibited two-phased reproduction and the ‘early’ daughter colonies reproduced just once. ‘Late’ colonies, together with the granddaughter generation, remained sterile. Four generations are described for the brooder C. craticula, three of which continuously produced larvae. While the two species co-exist on the same substratum, reproduction in E. pilosa started almost 1 month later (in late June), which could be explained by the insufficient abundance of phytoplankton in early summer to support the start of oogenesis and feeding cyphonautes larvae. The estimated maximal colony lifespan is 13 months in E. pilosa and 15 months in C. craticula. The broad comparison of bryozoan reproductive ecology in the White Sea showed that their life histories are much more diverse, complex and evolutionarily flexible than previously acknowledged.

Organisation(s)
Department of Palaeontology
External organisation(s)
Saint Petersburg State University, Russian Academy of Sciences
Journal
Invertebrate Reproduction & Development
Volume
64
Pages
137-157
No. of pages
21
ISSN
0792-4259
DOI
https://doi.org/10.1080/07924259.2020.1729260
Publication date
2020
Peer reviewed
Yes
Austrian Fields of Science 2012
106054 Zoology
Keywords
ASJC Scopus subject areas
Animal Science and Zoology, Developmental Biology
Portal url
https://ucrisportal.univie.ac.at/en/publications/7cef5a8e-9600-495a-b44a-ee8f0257a53b