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Bathylasma Alearum
''Bathylasma alearum'' is a species of barnacles in the Pachylasmatidae family. The species is androdioecious Androdioecy is a reproductive system characterized by the coexistence of males and hermaphrodites. Androdioecy is rare in comparison with the other major reproductive systems: dioecy, gynodioecy and hermaphroditism. In animals, androdioecy has bee .... References {{Taxonbar, from=Q13436437 Barnacles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barnacle
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmobile) and most are suspension feeders, but those in infraclass Rhizocephala are highly specialized parasites on crustaceans. They have four nektonic (active swimming) larval stages. Around 1,000 barnacle species are currently known. The name is Latin, meaning "curl-footed". The study of barnacles is called cirripedology. Description Barnacles are encrusters, attaching themselves temporarily to a hard substrate or a symbiont such as a whale ( whale barnacles), a sea snake ('' Platylepas ophiophila''), or another crustacean, like a crab or a lobster (Rhizocephala). The most common among them, "acorn barnacles" ( Sessilia), are sessile where they grow their shells directly onto the substrate. Peduncul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachylasmatidae
Pachylasmatidae is a family of symmetrical sessile barnacles in the order Balanomorpha. There are about 10 genera and at least 30 described species in Pachylasmatidae. Genera These genera belong to the family Pachylasmatidae: * '' Atetrapachylasma'' Newman & Jones, 2011 * '' Eolasma'' Buckeridge, 1983 * ''Eurylasma'' Jones, 2000 * ''Eutomolasma'' Jones, 2000 * ''Metalasma'' Jones, 2000 * ''Microlasma'' Jones, 2000 * '' Neoeolasma'' Gale, 2020 * ''Pachylasma'' Darwin, 1854 * ''Pseudoctomeris'' Poltarukha, 1996 * ''Tetrapachylasma ''Tetrapachylasma'' is a genus of symmetrical sessile barnacles in the family Pachylasmatidae Pachylasmatidae is a family of symmetrical sessile barnacles in the order Balanomorpha The Balanomorpha are an order of barnacles, containing fami ...'' Foster, 1988 References {{Taxonbar, from=Q11846340 Sessilia Crustacean families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androdioecy
Androdioecy is a reproductive system characterized by the coexistence of males and hermaphrodites. Androdioecy is rare in comparison with the other major reproductive systems: dioecy, gynodioecy and hermaphroditism. In animals, androdioecy has been considered a stepping stone in the transition from dioecy to hermaphroditism, and vice versa. Androdioecy is sometimes referred to as a mixed breeding system with trioecy and gynodioecy. It is a dimorphic sexual system in plants alongside gynodioecy and dioecy. Evolution of androdioecy The fitness requirements for androdioecy to arise and sustain itself are theoretically so improbable that it was long considered that such systems do not exist. Particularly, males and hermaphrodites have to have the same fitness, in other words the same number of offspring, in order to be maintained. However, males only have offspring by fertilizing eggs or ovules of hermaphrodites, while hermaphrodites have offspring both through fertilizing eggs or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
