Triops cancriformis

Triops cancriformis, commonly known as the European tadpole shrimp, is a species of tadpole shrimp found across Europe, the Middle East, and India. It is considered endangered in the United Kingdom and several other European countries due to habitat destruction. In captivity, it grows up to 6 cm (2.4 in), but in the wild, individuals can reach sizes of 11 cm (4.3 in). The species is legally protected under Schedule 5 of the UK's Wildlife and Countryside Act 1981. The known populations in the UK are located in a pool at Caerlaverock Wetlands in Scotland and a temporary pond in the New Forest. Fossils attributed to this species were previously thought to belong to Triassic taxa, but later research reclassified them as separate extinct groups. Genetic evidence shows that T. cancriformis diverged from other Triops species around 23.7–49.6 million years ago. The life cycle of T. cancriformis is rapid, with individuals maturing in two weeks. Populations can be gonochoric, hermaphroditic, or androdioecious, a rare reproductive mode where males are scarce. Females or hermaphrodites produce diapausing eggs that can survive for decades in pond sediments. The taxonomic history of T. cancriformis is complex. It was first described as Apus cancriformis by Bosc in 1801 but later reclassified due to the pre-emption of the genus name by a bird genus. In 1955, Longhurst supported using Triops instead of Apus, and the ICZN officially recognized "Triops cancriformis" as the valid name. Despite lacking economic importance, T. cancriformis has been used to control mosquitoes ...