The number of people who think shrimp are fish is tragic, so let’s clear up a few things!
Shrimp are invertebrates, lacking a backbone. It is ‘important’ to recognise that not all animals commonly called shrimp are actually shrimp. The well-known mantis shrimp, for example, is a stomatopod rather than a decapod. They’re also terrifying.
Kingdom – Animalia: Shrimp are animals.
Phylum – Arthropoda: Shrimp are arthropods.
Subphylum – Crustacea: Shrimp are crustaceans.
Class – Malacostraca: Shrimp are malacostracans.
Order – Decapoda: Shrimp are decapods.
Suborder – Pleocyemata: Shrimp are pleocyematans(?).
Infraorder – Caridea: Shrimp are carideans.
I focus on the shrimp with the following further taxonomic groups.
Family – Atyidae
Genus – Caridina, (Others include Paracaridina, Neocaridina, Halocaridina)
‘Caridina’ is apparently derived from Greek for ‘small shrimp’ or ‘small crustacean’. Thanks to Werner Klotz for this information.
‘Para-‘ is a Greek root for ‘near’. Paracaridina – near ‘Caridina’.
‘Neo-‘ is a Greek root for ‘new’. Neocaridina – new ‘Caridina’.
‘Halo-‘ is a Greek root for ‘salt’. Halocaridina – salt ‘Caridina’. [These species have salt tolerance.]