Sphaeriidae is a
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
of small to minute freshwater
bivalve
Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, biv ...
molluscs in the
order
Order, ORDER or Orders may refer to:
* Categorization, the process in which ideas and objects are recognized, differentiated, and understood
* Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...
Sphaeriida. In the US, they are commonly known as pea clams or fingernail clams.
[ Heard, William H. 1977. Reproduction of fingernail clams (Sphaeriidae: ''Sphaerium'' and ''Musculium''). Malacologia, 16: 421-455.]
Genera
Genera:
*
Euperinae
** ''
Byssanodonta''
d'Orbigny, 1846
** ''
Eupera''
Bourguignat, 1854
*
Sphaeriinae
** ''
Afropisidium''
Kuiper, 1962
** ''
Euglesa''
Jenyns, 1832
** ''
Musculium''
Link, 1807
** ''
Odhneripisidium''
Kuiper, 1962
** ''
Pisidium
''Pisidium'' is a genus of very small or minute freshwater clams known as pill clams or pea clams, aquatic bivalve molluscs in the family Sphaeriidae, the pea clams and fingernail clams.
In some bivalve classification systems, the family S ...
''
C. Pfeiffer, 1821
** ''
Sphaerium''
Scopoli, 1777
* fossils
** †''
Megasphaerioides''
Komatsu, J.-H. Chen & Q.-F. Wang, 2003
** †''
Protosphaerium''
Hocknull, 2000
** †''
Sphaericoncha''
Kolesnikov, 1980
Biology and ecology
Sphaeriidae are
hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes.
Many taxonomic groups of animals (mostly invertebrates) do not have ...
s with internal fertilization. Developing young are incubated within their mother (
ovoviviparity
Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop insi ...
), and newborn clams look like miniature copies of the adults.
[
]Parasite
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of lif ...
s and/or predators include the Sciomyzidae
The family Sciomyzidae belongs to the typical flies ( Brachycera) of the order Diptera. They are commonly called marsh flies, and in some cases snail-killing flies due to the food of their larvae.
Here, the Huttoninidae, Phaeomyiidae and Tet ...
.
References
{{Authority control
Bivalve families