Narrow-bordered bee hawk-moth (Hemaris tityus)
|Size||Wingspan: 41-46 mm (1)|
Classified in Great Britain as Nationally Scarce (2).
Adults of the Narrow-bordered Bee Hawk-moth are extremely similar in appearance to bumblebees (3), and gain a level of protection from this mimicry. The wings are transparent with a thin brown border, and the body is furry and banded. The caterpillars may reach up to 3.5 cm in length, and have pale green bodies with purple or brownish-red blotches and a reddish horn towards the rear (4).
Once widespread but local throughout the UK, the Narrow-bordered Bee Hawk-moth underwent a severe decline from about 1950. It became extinct at many former sites, especially in the east of its range, surviving mainly in south-west England, west Wales, Northern Ireland and the west coast of Scotland. Welcome signs of a recovery have been noticed in the past decade, and the moth was re-found in East Anglia in 1999 (5). The species has a local distribution in the western Palaearctic, and has been recorded from most European countries (2).
Inhabits many types of unimproved grasslands. It also occurs on acid bogs, peat cuttings and dry heathland sites (2). In all cases, it requires a source of the foodplant of the caterpillars, devil's bit scabious (2), growing in a large area of suitable habitat (5).
The Narrow-bordered Bee Hawk-moth has a single generation each year (it is 'univoltine'). Adults are active in the day between mid-May and mid-June, and can be seen visiting the flowers of various species in sunshine (1). Eggs are laid singly underneath leaves of the foodplant, and hatch 1-2 weeks later. Caterpillars feed between July and August but are hard to find (5), and will fall to the ground when disturbed. The pupa overwinters in a cocoon spun below the surface of the soil (4).
The main factors affecting this species include agricultural improvement and unsuitable management of its grassland and heathland habitats (2), especially in southern and eastern England. Much suitable habitat remains in Scotland (5).
The Narrow-bordered Bee Hawk-moth has been targeted as a priority species under the UK Biodiversity Action Plan (UK BAP). The plan aims to maintain the current populations and to restore the species to 10 sites in the former range before 2010 (2). Many of the sites where this moth occurs are Sites of Special Scientific Interest (SSSIs) or nature reserves; a number of sites have been forwarded as candidate SACs (Special areas of Conservation) (2).
Further reading on moths:
Skinner, B. (1998) Colour Identification Guide to Moths of the British Isles. Viking Press, London.
Leverton, R. (2001) Enjoying Moths. Poyser, London.
Information authenticated by Roy Leverton.
- Palaearctic region: the region that includes Europe, the part of Asia to the north of the Himalyan-Tibetan barrier, North Africa and most of Arabia.
- Pupa: stage in an insect's development when huge changes occur, which reorganise the larval form into the adult form. In butterflies the pupa is also called a chrysalis.
- Univoltine: (also known as 'single-brooded'). Insect life cycle that takes 12 months to be complete, and involves a single generation. The egg, larva, pupa or adult over winters as a dormant stage.
- Skinner, B. (1984) Colour Identification Guide to Moths of the British Isles. Viking Press, London.
- UK BAP (December 2001): http://www.ukbap.org.uk
- UK Moths (December 2001): http://www.ukmoths.force9.co.uk
- Carter, D. J. and Hargreaves, B. (1986) A Field Guide to caterpillars of butterflies and moths in Britain and Europe. Collins, London.
- Leverton, R. (2002) Pers. comm.