Soldierflies, their allies and Conopidae of Surrey was published in November 2015 and is the 15th in a series of atlases produced by Surrey Wildlife Trust dealing with the county's wildlife scientifically and systematically. Jointly written by David Baldock and myself, the book is A5 in size and contains 208 pages of text plus 32 colour plates.

Soldierflies and their allies, also known as the 'Larger Brachycera', are an attractive group of Diptera consisting of 11 families. Apart from soldierflies, they include bee-flies, horseflies, robberflies, snipeflies and stiletto flies. Some are brilliantly coloured, others are relatively drab. Some are highly active, others are more sedentary. Some are tiny, measuring just a couple of millimetres, a few are ten times that size, such as the Dark Giant Horsefly (Tabanus sudeticus). There are bloodsuckers, predators and parasitoids.

Despite being landlocked, and small by comparison with the majority of counties, Surrey has 104 of the 159 species in the national list; the latest addition, the Long-horned Cleg (Haematopota grandis), appeared in my garden in September as we were going to press. One hundred and four is an impressive score and puts Surrey near the top in Britain numerically. The total includes a significant proportion of the national populations of three iconic species - the Hornet Robberfly (Asilus crabroniformis), the Mottled Bee-fly (Thyridanthrax fenestratus) and the Golden-tabbed Robberfly (Eutolmus rufibarbis).

Significantly, a high proportion of the soldierflies and their allies are scarce, more than for any other group of invertebrates covered in the atlas series. In keeping with this, generally they are not easy to find and the same can be said for the Conopidae, which are parasitoids of bees and wasps. Thanks to its rich bee and wasp fauna, Surrey has 19 of the 23 species that make up the British list of conopid flies.

The atlas carries a distribution map for each species recorded since the 1980s. For all species there are notes on the life cycle as well as full records for those with 20 or fewer records. There are also details on how to find the flies, analysis of the best sites in Surrey with species lists for the top four, data about enemies and predators, and a full list of references. The colour plates show more than 80 species, mostly in the wild and often displaying characteristic behaviour.

This is the first comprehensive county guide to these families, which merit closer attention than they have sometimes received. Copies of Soldierflies, their allies and Conopidae of Surrey are available in the United Kingdom at £18 from Surrey Wildlife Trust surreywildlifegifts.org.uk.

Photographs of a number of the species covered by the atlas are shown on this page: Soldierflies & Allies.