In the pedunculate barnacle Alepas pacifica Pilsbry, 1907, a symbiont of jellyfish, several small individuals were found attached to conspecifics rather than directly to the host. We investigated whether these individuals act as dwarf males, as is known in some other species of barnacles. The conspecific-attached individuals had longer penes than juvenile hermaphrodites of similar sizes attached directly to the jellyfish, although there was no other morphological difference between these two types of individuals. Only the largest conspecific-attached individual was ovigerous. We conclude that the conspecific-attached individuals are dwarf males, which develop the male function at a smaller size than hermaphrodites do, with a small possibility of becoming hermaphroditic. This is the first report of dwarf males, and hence of the coexistence of males and hermaphrodites (androdioecy), in the family Lepadidae. In addition, the record of A. pacifica attached to Nemopilema nomurai Kishinouye, 1922, is reported herein as new to science.
BarazandehM.DavisC. S.NeufeldC. J.ColtmanD. W.PalmerA. R.2013.
Something Darwin didn’t know about barnacles: spermcast mating in a common stalked species.
Proceedings of the Royal Society B: Biological Sciences280: 20122919.
BarazandehM.DavisC. S.PalmerA. R.2014.
Where even a long penis can’t help: evidence of long-distance spermcast mating in two acorn barnacles.
Journal of Experimental Marine Biology and Ecology454:
Reproduction and larval development in three scalpellid barnacles, Scalpellum scalpellum (Linnaeus 1767), Ornatoscalpellum stroemii (M. Sars 1859) and Arcoscalpellum michelottianum (Seguenza 1876), (Crustacea: Cirripedia: Thoracica): implications for reproduction and dispersal in the deep sea.
Reproductive strategy of two deep-sea scalpellid barnacles (Crustacea: Cirripedia: Thoracica) associated with decapods and pycnogonids and the first description of a penis in scalpellid dwarf males.
Organisms Diversity and Evolution13:
Reproductive ecology of the pedunculate barnacle Scalpellum stearnsii (Cirripedia: Lepadomorpha: Scalpellidae).
Journal of the Marine Biological Association of the U.K.88:
Biological associations between barnacles and jellyfish with emphasis on the ectoparasitism of Alepas pacifica (Lepadomorpha) on Diplulmaris malayensis (Scyphozoa).
Journal of Natural History34:
Cypris settlement and dwarf male formation in the barnacle Scalpellum scalpellum: a model for an androdioecious reproductive system.
Journal of Experimental Marine Biology and Ecology422-423:
Dwarf males, large hermaphrodites and females in marine species: a dynamic optimization model of sex allocation and growth.
Theoretical Population Biology85:
Dwarf males and hermaphrodites can coexist in marine sedentary species if the opportunity to become a dwarf male is limited.
Journal of Theoretical Biology334:
Dwarf males of Octolasmis warwickii (Cirripedia: Thoracica): the first example of coexistence of males and hermaphrodites in the suborder Lepadomorpha.
Ecology of a parasitic barnacle, Koleolepas avis, relationship to the hosts, distribution, left-right asymmetry and reproduction.
Journal of the Marine Biological Association of the U.K.81: