Triaspiron

Triaspiron is a monotypic genus of acanthocephalans (thorny-headed or spiny-headed parasitic worms) containing a single species, Triaspiron aphanii.

Taxonomy and description
T. aphanii resembles Raosentis Datta, 1947 by having a small spindle shaped trunk. Triaspiron differs from Raosentis in the shape of the proboscis (cylindrical not globular), proboscis armed with 16 hooks divided into three circles (not four circles), and a total of between 26 and 30 hooks in all. Triaspiron also differs by the spines on the trunk: there are two separate regions of spines in the anterior region arranged in up to 40 circular rows, not a single field with 9 to 17 rows of spines.

Triaspiron also resembles the genus Acanthogyrus Thapar, 1927, by having three circles of hooks on the proboscis. Triaspiron differs from Acanthogyrus in having fewer proboscis hooks, 16 compared with between 18 and 24, that are arranged in three circles, one anterior circle followed by an unarmed region followed by two posteriorly circles instead of three circles of hooks evenly spaced. It also has two fields of trunk spines instead of one. Triaspiron aphanii is the type species.

The National Center for Biotechnology Information does not indicate that any phylogenetic analysis has been published on Triaspiron that would confirm its position as a unique order in the family Quadrigyridae.

Distribution
The distribution of T. aphanii is determined by that of its hosts, which are found in Kirkgöz Springs, Antalya, Turkey.

Hosts
The life cycle of an acanthocephalan consists of three stages beginning when an infective acanthor (development of an egg) is released from the intestines of the definitive host and then ingested by an arthropod, the intermediate host. Although the intermediate hosts of Triaspiron are not known. When the acanthor molts, the second stage called the acanthella begins. This stage involves penetrating the wall of the mesenteron or the intestine of the intermediate host and growing. The final stage is the infective cystacanth which is the larval or juvenile state of an Acanthocephalan, differing from the adult only in size and stage of sexual development. The cystacanths within the intermediate hosts are consumed by the definitive host, usually attaching to the walls of the intestines, and as adults they reproduce sexually in the intestines. The acanthor is passed in the feces of the definitive host and the cycle repeats. There are no known paratenic hosts (hosts where parasites infest but do not undergo larval development or sexual reproduction) for Triaspiron.

Triaspiron was found to infest 90% of a sample of Iridescent toothcarp (Aphanius mento). There are no reported cases of any Triaspiron species infesting humans in the English language medical literature.