''Hausera'' is a subterranean genus of

planarian Planarians (triclads) are free-living flatworms of the class Turbellaria, order Tricladida, which includes hundreds of species, found in freshwater, marine, and terrestrial habitats.pp 3., "Planarians (the popular name for the group as a whole ...

from Brazil. It contains only the single species ''Hausera hauseri''. It is the first cave-dwelling member of the

suborder Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized ...

Cavernicola to have been observed in South America.

Etymology

Both the genus and species were named after Josef Hauser, a researcher of freshwater

flatworm Platyhelminthes (from the Greek language, Greek πλατύ, ''platy'', meaning "flat" and ἕλμινς (root: ἑλμινθ-), ''helminth-'', meaning "worm") is a Phylum (biology), phylum of relatively simple bilaterian, Segmentation (biology), ...

Description

Specimens are long and wide. The

pharynx The pharynx (: pharynges) is the part of the throat behind the human mouth, mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates ...

is long, and along with the

gonopore A gonopore, sometimes called a gonadopore, is a genital pore in many invertebrates. Hexapods, including insects, have a single common gonopore, except mayflies, which have a pair of gonopores. More specifically, in the unmodified female, it is ...

is located in the hindmost third of the body. While it lacks eyes, the head has a pair of ciliated sensory organs approximately 140 μm back from the body's anterior end. The intestine extends into the brain and connects with the reproductive system via a genito-intestinal duct. The testicular follicles are arranged in uneven rows near the margins of the body, and the

ovaries The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are endocr ...

are located behind but in proximity to the brain, approximately 0.6 millimeters behind the body's tip. The species is colorless.

Range and habitat

''Hausera hauseri'' was found in a

perennial stream A stream is a continuous body of surface water flowing within the bed and banks of a channel. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long, large stream ...

in Crotes cave, part of the Lagedo do Rosário cave system in Felipe Guerra,

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. The water in the stream was to deep.

References

{{Taxonbar, from=Q18348719 Cavernicola (worm) Platyhelminthes of Brazil Monotypic platyhelminthes genera