''Barbronia weberi'' is a species of predatory freshwater

leech Leeches are segmented parasitic or predatory worms that comprise the subclass Hirudinea within the phylum Annelida. They are closely related to the oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodie ...

in the family

Salifidae Salifidae is a family of annelids belonging to the order Arhynchobdellida. Genera: * '' Barbronia'' Johansson, 1918 * '' Linta'' Westergren & Siddall, 2004 * '' Lumbricobdella'' Kennel, 1886 * '' Mimobdella'' * '' Odontobdella'' * '' Salifa'' B ...

. It is native to southeastern Asia but has spread to other parts of the world, including Australia, South America, southern Europe and the United States.

Description

''Barbronia weberi'' grows to a body length of about , with individuals becoming sexually mature from a length of about . The body is about wide and the rear suction cup has a diameter of approximately . The body surface is covered with tiny papillae and is a uniform red to dark reddish-brown colour, sometimes almost black. There are always three pairs of eyespots on the head. The segments are not externally recognizable, and the seventeen body segments each comprise five outer annulations. In the

pharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...

, there are one or two retractile stylets on each of the three jaws. Between the male and female sex opening of the

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 Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

animals there are five or fewer annulations. On the ventral surface, there is a central accessory copulation pore next to the gonopores, but this is absent in young animals.

Distribution and habitat

The species is native to India, southeastern Asia, the Philippines and Indonesia. From here it has spread to Australia, Europe and South America. It is a freshwater species. In 2018 it was reported from two widely separated locations in

North Carolina North Carolina () is a state in the Southeastern region of the United States. The state is the 28th largest and 9th-most populous of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, Georgia and So ...

, but it is unclear whether these are as a result of two different introductions, or mean that the leech has become widely distributed but has previously been overlooked.

Ecology

As is the case with all leeches, ''B. weberi'' is a

; sperm is passed from one individual to another by

traumatic insemination Traumatic insemination, also known as hypodermic insemination, is the mating practice in some species of invertebrates in which the male pierces the female's abdomen with his aedeagus and injects his sperm through the wound into her abdominal c ...

. The eggs are fertilised and a cocoon is secreted by the

clitellum The clitellum is a thickened glandular and non-segmented section of the body wall near the head in earthworms and leeches, that secretes a viscid sac in which eggs are stored. It is located near the anterior end of the body, between the fourteent ...

and receives the from one to five eggs as it passes over the female gonopore. The eggs hatch in about one month and the juvenile leeches that emerge become mature in about four months. The adult can produce weekly cocoons for about three months before becoming

senescent Senescence () or biological aging is the gradual deterioration of functional characteristics in living organisms. The word ''senescence'' can refer to either cellular senescence or to senescence of the whole organism. Organismal senescence invol ...

. Adults are often found attached to water plants, and the cocoons containing eggs are attached to rocks, submerged objects or aquatic vegetation at the base of leaf whorls; it seems likely that the transport of aquatic plants by the aquarium trade is the means by which the leech has dispersed to new locations. This leech can be successfully reared egg to egg in the laboratory, and may be of use as a

model organism A model organism (often shortened to model) is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the model organism will provide insight into the workin ...

in developmental studies.

References

{{Taxonbar, from=Q5179133 Leeches Animals described in 1897