Paraphaenocladius impensus

Author: (Walker, 1856)

Diagnosis (n=3, in part after Saether and Wang, 1995a - in italics)
Exuviae 2.8-3.1mm long (065-1.jpg).
Cephalothorax: Frontal setae and warts absent. Thoracic horn elongate, 135-180µm long, toothed apically; ThR 9.0-11.2. Thoracic horn 180-219µm long (m=194µm, n=4-5); 15-23µm wide (m= 18µm); 3.13-4.00x (n=3) as long as terminal seta on anal lobe. Precorneal setae, median and lateral antepronotals each 60-98µm long (m=70µm). Dorsocentrals each 19-60µm long (m=31µm); distance between setae 1 and 2: 56-118µm (m=99µm; 1x 56µm, the others 105-118µm); between setae 2 and 3: 13-75µm (m=31µm; 1x 75µm, the others 13-23µm); between setae 3 and 4: 15-23µm (m=19µm). Wing sheaths with both nose and pearl row at apex (the pearl row may be squashed flat on mounts) (065c.jpg); with 45-60 pearls (m=51).
Abdomen: Hook row II absent. Tergite I bare, II-VIII with extensive shagreen, only less extensive on VII and VIII. Sternites I-III bare, IV and V with postero-median points, VII and VIII with a few postero-median points. Shagreen grading over into small posterior spines distinct on tergites VI-VIII and indistinct on sternites VI-VII (female) or VIII (male).
Anal segment: Tergite IX with anteriomedian points. Anal lobe ratio 1.4-1.9. Anal lobes without fringe. Anal lobes usually folded inwards and so appearing parallel-sided and apically truncate; apically toothed and with only one fine bristle-like seta (occasionally missing), (0), 40, 55µm long (065e.jpg). Apex of anal lobe with 16-22, 18 spines; terminal seta 45-60µm long (n=2) and about 0.7µm wide (n=2). Genital sac of male overreaches anal lobe by 99µm (n=1); of female ending 15-34µm (m=23µm) short of apex.
(Linked adult male: Langton and Pinder, 2003a)

Species keys out at Page 804: Orthocladiinae 216 Paraphaenocladius of the Text Key.

Holarctic species: widespread in Europe, see also Paraphaenocladius impensus albusalatus and Paraphaenocladius impensus contractus.
(For more information see module IdentifyIt – file: Orthocladiinae).

Ecological notes
Streams, ditches, drains and lakes. Larvae in wet moss by a stream.