70.075 Hydriomena impluviata (May Highflyer)
fw: 13-16mm; May-Jul; alder (Alnus glutinosa); common in damp woodland throughout GB
Hydriomena impluviata (May Highflyer) §2 male
ID: Distinguished from H.furcata (July Highflyer) by flight season and possession of 2-3 short black streaks between the veins near the forewing apex. H.ruberata (Ruddy Highflyer) also has these streaks. Reddish forms of H.ruberata are distinct as H.impluviata is never reddish. H.impluviata is said to be distinguishable from H.ruberata by forewing shape - shorter and broader in H.impluviata, according to Waring.
Male genitalia: The uncus of H.furcata is notched while that of both H.impluviata and H ruberata is clearly bilobed. In H.impluviata the uncus lobes are of approximately even width throughout their length and the junction of uncus and tegumen has a width of two uncus lobes. In H.ruberata the uncus lobes broaden towards the apex and the junction of uncus and tegumen has a width of the apical portion of one uncus lobe.
Female genitalia: I have not been able to discern the difference between H.impluviata/ruberata from the images at dissection group or from the description in Pierce ("bursa hardened on one third obliquely" in H.ruberata "bursa hardened on one third not obliquely" in H.autumnalis which I assume is what Pierce is calling H.impluviata).
Male genitalia: The uncus of H.furcata is notched while that of both H.impluviata and H ruberata is clearly bilobed. In H.impluviata the uncus lobes are of approximately even width throughout their length and the junction of uncus and tegumen has a width of two uncus lobes. In H.ruberata the uncus lobes broaden towards the apex and the junction of uncus and tegumen has a width of the apical portion of one uncus lobe.
Female genitalia: I have not been able to discern the difference between H.impluviata/ruberata from the images at dissection group or from the description in Pierce ("bursa hardened on one third obliquely" in H.ruberata "bursa hardened on one third not obliquely" in H.autumnalis which I assume is what Pierce is calling H.impluviata).
§1 Strumpshaw Fen, Norfolk; 09/06/2008
§2 Strumpshaw Fen, Norfolk; 29/04/2011; male; fw 14.0mm
§3 Newgale, Pembrokeshire; 14/05/2011; female
§4 Strumpshaw Fen, Norfolk; 25/05/2018
§5 New Forest, Hampshire; 30/05/2023; male; fw 13.2mm
§6 New Forest, Hampshire; 30/05/2023; female; fw 15.1mm
§7 New Forest, Hampshire; 30/05/2023; male; fw 14.4mm
§8 New Forest, Hampshire; 30/05/2023
§9 New Forest, Hampshire; 30/05/2023
All images © Chris Lewis
§2 Strumpshaw Fen, Norfolk; 29/04/2011; male; fw 14.0mm
§3 Newgale, Pembrokeshire; 14/05/2011; female
§4 Strumpshaw Fen, Norfolk; 25/05/2018
§5 New Forest, Hampshire; 30/05/2023; male; fw 13.2mm
§6 New Forest, Hampshire; 30/05/2023; female; fw 15.1mm
§7 New Forest, Hampshire; 30/05/2023; male; fw 14.4mm
§8 New Forest, Hampshire; 30/05/2023
§9 New Forest, Hampshire; 30/05/2023
All images © Chris Lewis
Page published 28/04/2013 (§1-3) | §4 added Jan 2019 | §5-9 added 06/06/2023
