Procladius pe1

Form described by Langton, 1991

Exuviae 6.3-8.3mm long (m=7.0mm, n=17).
Cephalothorax: Thoracic horn cylindrical, with a transversely oval to circular plastron plate filling the horn apex, which is joined to the broad brown respiratory atrium by a broad but short neck. Thoracic horn 505-685µm long (m=590µm, n=19); ThR 2.8-4.7 (m=3.3, n=17). Breadth respiratory atrium : breadth horn = 0.66-0.91:1 (m=0.81:1, n=11). (007d.jpg)
Abdomen: Tergite IV (especially postero-laterally) with strong, dense, irregularly arranged points in which the circular bare patches around the dorsal setae show up very clearly (007d.jpg). Anterior lateral taenia of segment VII at 0.43-0.56 of length segment VII (m=0.49, n=17). Segment VIII extended posteriorly on each side for over one fifth its median length.
Anal segment: Anal lobes Procladius-type. Anal lobe ratio 1.76-2.17 (m=1.9, n=17).

Exuviae from northern Scotland are on the whole smaller with narrower respiratory atria:
-Procladius pe1a Exuviae 7.2-8.3mm long (m=7.6mm, n=7). Thoracic horn 580-685µm long (m=619µm, n=13). Breadth respiratory atrium : breadth horn = 0.82-0.88:1 (m=0.85:1, n=11). Southern Scotland and northern England.
Note: In Lake Korta, Norway, 1150m asl, is a population with reduced male antennal sheaths (as in Procladius fimbriatus). The anal lobes are narrower and the marginal teeth more widely spaced medially (in pe1 evenly spaced). It is unlikely to be the same species as pe1. The adult male hypopygium has a very long basal projection on the gonostyle.

-Procladius pe1b Exuviae 6.3-7.5mm long (m=6.7mm, n=10). Thoracic horn 505-540µm long (m=526µm, n=6). Breadth respiratory atrium : breadth horn = 0.76-0.85:1 (m=0.80:1, n=5). Northern Scotland.

Form keys out at Page 22: Tanypodinae 8 Procladius of the Text Key.

SW Europe.
(For more information see module IdentifyIt – file: Other subfamilies).

Ecological notes
Stagnant water; commonest in the north and on high mountains.