Worcestershire Record No. 3 November 1997 p. 8
Scarce Ground Beetle Found At Devils Spittleful & Rifle Range
Nationally Notable (Scarce) Category B - Nb - NOTABLE B. Found grubbing under detritus and dead leaves around silver birches and heather; identified with Lindroth (1974), a recently newly reprinted RES key; confirmed by Paul F. Whitehead. Listed in Hyman and Parsons (1992) as widespread but local throughout Britain. Sandy heath (as is the Devils Spittleful) is a known habitat - so are sand dunes, chalk soils, and arable field margins - but these fields are probably in the Brecks (a large sandy area) says Paul Whitehead. Also recorded from old railway tracks and ornamental deciduous woodland. Found often under dry leaves. Adults recorded April-August.
Has not been previously recorded for Worcestershire BRC. Widespread in Britain but local as could be expected. Some habitats are under threat of destruction; some are degraded by natural succession into woodland, so maintenance of bright, open conditions is required. Perhaps in summary it requires the sort of ground that has a surface that warms quickly in the sun - that is, dry, sandy to gravelly, and lightly vegetated - as the beetle needs warmth for activity. Exposed sand at the very surface warms quickly in sun and heats air just above. Hence a significantly warmer microclimate on the surface and above just a few millimeters high, supporting beetle activities periodically when the weather would be otherwise to cold. Hymen and Parsons say the adult is vegetarian. The larvae is predatory - which could imply the larvae is more dependent on microclimatical warm periods than the adult, because heat is necessary to allow strenuous, muscular activity necessary for catching and restraining prey compared with eating a seed.
Lindroth (1949, Fennoscandia) says it prefers dry conditions, and is tolerant of soils, even uniform particles, of diverse particle sizes from gravel to fine particles (in the case of the Spittleful, fine and sandy), and is averse to cultivated land. From observations the adult food is probably exclusively seeds, and fruits (perhaps for the water). Many adult carabids apparently scavenge a mixed diet of fresh dead animal and vegetable; many Amara species adults eat plants mostly.
Amara - there are about 30 species of Amara in Britain; generally of similar characteristic body shape as in the drawing (that was made with the help of a squared graticule on a microscope) with short legs, two long hairs next to the eye; often with a brassy surface lustre, owing to microscopic regular engraved lines on the surface, or more shiny. They are usually found in dryer places, in open country with short vegetation, under matted plant or dry leaves, rather than stones or logs, which is the place to find many carabids.
References:
Hyman PS and Parsons MS (1992) A Review of Scarce and threatened Coleoptera of Great Britain. JNCC Peterborough.
Lindroth, CH (1949, Fennoscandia) - translation 1992: Ground Beetles (Carabidae) of Fennoscandinavia. A Zoogeographic Study. Part 3, Intercept, Andover, England.
| Lindroth, Carl H (1974) - reprint 1996 - Coleoptera: Carabidae. Handbooks for the Identification of British Insects. Vol 4, part 2. Royal Entomological Society of London.
| Whitehead, Paul F (1998) pers com.
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