|Notiophilus substriatus Waterhouse, G.R., 1833|
|Found throughout Great Britain to the northernmost parts of scotland and the Western Isles
although with only scattered records from the highlands. The species prefers open dry habitats e.g. short cropped
grass or scrubland with patchy vegetation and seems at home around human habitation. In our experience nowhere so
abundant as N.biguttatus Fab. but we have recorded them throughout
Watford. Recording from the field can be problematic as they have the pale elytral mark as in N.biguttatus so
will need to be examined under the microscope for a sure identification. Around Watford the majority of the
specimens are biguttatus, substriatus occurs erratically and usually only as single specimens,
finding a specimen and then returning to search for more is rarely successful, we have found them in parkland,
gardens and on pathways around sportsfields, always dry, open habitats and usually active in bright sunshine.
All our records lie between March and June, no doubt the period of maximum activity as they are spring breeders.
4.5-5.5mm. Antennae black with three basal segments pale at least in part. Legs black usually with metallic bronze lustre (N.rufipes Curtis), tibiae at least in part rufous. Basal protarsal segments dilated in male. Head across eyes slightly narrower than pronotum, strongly metallic and dull to strong microsculpture especially behind central carinae. Pronotum transverse, sides strongly sinuate and anterior margin produced at middle. Black with metallic lustre and dense puncturation towards margins. Scutellum almost semicircular, dull metallic due to microsculpture. Elytra with pale apical mark usually extending laterally towards middle, fourth interstice with three strong punctures, one before middle and two preapical. Second interval more than three times wider than third at middle, shining so contrasting strongly against 3-7 which are microsculptured and so dull ¹ ². All interstices flat and puncturation of entire upper surface fine ² (cf. biguttatus Fab. and quadripunctatus Dj.)
¹ If you are using Forsythe's work care must be taken with this, it states 'outer eltral intervals dull, contrasting with second interval' but this is not the case in our Watford specimens. In ours some outer intervals (3-7) are dull, 8 and 9 are shining as, or virtually as, 2. ² Elytral microsculpture and flat interstices are readily appreciated without the need for comparative material. The question of puncturation strength is best appreciated with substriatus and biguttatus side by side. In any case substriatus should be obvious.
Description from 2 Watford specimens at X20
See ID Aids for Key to all British Notiophilus