T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Beetle (Water scavenger) Dactylosternum abdominale

Kingdom: Animalia (Animals)
Phylum: Arthropoda (Arthropods)
Class: Insecta (Insects)
Order: Coleoptera (Beetles)
Suborder: Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
Superfamily: Hydrophiloidea (Water Scavenger and Clown Beetles)
Family: Hydrophilidae (Water Scavenger Beetles)
Subfamily: Sphaeridiinae
Tribe: Coelostomatini
Genus: Dactylosternum
Species: D. abdominale
Binominal name: Dactylosternum abdominale
Common name:   Water scavenger beetle.

Dactylosternum abdominale is a small (4mm) shiny black exotic insect widely spread around the world. Its habitat is amongst putrid substances generally vegetable or animal. It is found usually at low elevations, about towns, silage, composts and in gardens.
Dactylosternum abdominale are predators on the larvae of other insects and there is evidence to suggest it is a predator of the biting fly Stomoxys calcitrans (Stable fly).
New Zealand Ministry of Agriculture on 13-Aug-2001 classed it as an unwanted pest and placed it in the regulated pest category.

A 4 mm water scavenger beetle

The beetle's underside.

Underside with head pulled into the shell

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/