Almidae
Encyclopedia
The animal family Almidae includes about six genera of segmented worms
.
A notable peculiarity of some species in this family is a tendency to extensions of the body wall in the vicinity of or including the male pores. These extensions may be mere protuberances, as in some species of Drilocrius; or involve a greater extent of the body wall, as in genus Glyphidrilocrius. They take the form of wing or keel-like structures called alae in Glyphidrilus species and paddle-shaped claspers in Drilocrius alfari.
All species of genus Alma have claspers. The male pores are near the tips of these claspers, and they are furnished with genital chaeta
e and sucker-like structures.
Most members of this family have one pair of male pores on segment 15 through 30. Female pores are located on segment 14. Glyphidrilus kukenthali is one of only three ‘earthworm’ species known to have two pairs of female pores, in 13 and 14.
A possibly related family is Criodrilidae
that contains genera Criodrilus and Biwadrilus with male pores in 15 and 13, respectively. Spermatheca
e are absent (a rare condition in oligochaetes
) and one to several spermatophore
s containing the sperm are transferred between partners and attached near the genital field.
Oligochaeta
Oligochaeta is a subclass of animals in the biological phylum Annelida, which is made up of many types of aquatic and terrestrial worms, and this includes all of the various earthworms...
.
A notable peculiarity of some species in this family is a tendency to extensions of the body wall in the vicinity of or including the male pores. These extensions may be mere protuberances, as in some species of Drilocrius; or involve a greater extent of the body wall, as in genus Glyphidrilocrius. They take the form of wing or keel-like structures called alae in Glyphidrilus species and paddle-shaped claspers in Drilocrius alfari.
Chaeta
A chaeta or cheta is a chitinous bristle or seta found on an insect, arthropod or annelid worms such as the earthworm, although the term is also frequently used to describe similar structures in other invertebrates. The plural form is chaetae or chetae.In the Polychaeta, they are located on the...
e and sucker-like structures.
Most members of this family have one pair of male pores on segment 15 through 30. Female pores are located on segment 14. Glyphidrilus kukenthali is one of only three ‘earthworm’ species known to have two pairs of female pores, in 13 and 14.
A possibly related family is Criodrilidae
Criodrilidae
The family Criodrilidae is represented by genera Criodrilus and Biwadrilus that are limicolous and/or aquatic earthworms endemic to the Palaearctic currently known only from Europe and Japan, respectively...
that contains genera Criodrilus and Biwadrilus with male pores in 15 and 13, respectively. Spermatheca
Spermatheca
The spermatheca , also called receptaculum seminis , is an organ of the female reproductive tract in insects, some molluscs, oligochaeta worms and certain other invertebrates and vertebrates...
e are absent (a rare condition in oligochaetes
Oligochaeta
Oligochaeta is a subclass of animals in the biological phylum Annelida, which is made up of many types of aquatic and terrestrial worms, and this includes all of the various earthworms...
) and one to several spermatophore
Spermatophore
A spermatophore or sperm ampulla is a capsule or mass created by males of various animal species, containing spermatozoa and transferred in entirety to the female's ovipore during copulation...
s containing the sperm are transferred between partners and attached near the genital field.