Cranefly (Hexatomini)

Taxonomic group

Tipulidae: Hexatomini

Diagnostic features

The Hexatomini is a tribe of tipulid craneflies that includes some common species with freshwater larvae. Like other tipulids the general body form is worm-like, with the head usually retracted into the body. The spiracular disc (breathing apparatus at the tip of the tail) is surrounded by 4 hair-fringed lobes. The body of some species is covered in fine hairs. Hexatomini larvae lack prominent abdominal creeping welts.

Hexatomini. Spiracular disc (breathing apparatus at the tip of the tail). Image: Stephen Moore Image — Hexatomini. Spiracular disc (breathing apparatus at the tip of the tail). Image: Stephen Moore

Hexatomini. Spiracular disc with 4 lobes. Image: Stephen Moore Image — Hexatomini. Spiracular disc with 4 lobes. Image: Stephen Moore

Typical habitats

Hexatomini larvae are found in many hard bottom and soft bottom streams around the country, though not usually in high abundance.

Feeding

They may have a range of feeding styles but their sharp sickle-like mandibles indicate they prey on other invertebrates.

Indicator value

Hard bottom: 5
Soft bottom: 6.7

The tolerance values (ranging from 0 to 10) give an indication of which are the sensitive taxa (values of 8 or more) and which are the tolerant taxa (values of 3 or less). For more information see: Indicator species

Hexatomini larvae are found in a wide range of stream types. They have mid range tolerance values of 5 (hard bottom sites) and 6.7 (soft bottom sites).