49.186 Endothenia gentianaeana (Teasel Marble)
ws: 15-19mm (BTM), fw: 6-9mm (Sterling & Parsons); May-Aug; teasel (Dipsocus fullonum); common on rough ground in England & Wales
Synonym: Argyroploce gentiana (Pierce & Metcalfe)
Synonym: Argyroploce gentiana (Pierce & Metcalfe)
ID: Similar to E.oblongana (11-15m) and E.marginana (11-16mm) but usually larger than these species, so that specimens with fw>7mm should be E.gentianaeana. There is considerable variation in forewing markings especially in the extent of white irroration of the basal area and the extent of black spots in the markings. Several differences from its congeners are mentioned in BTM and Clifton&Wheeler, but I am not (yet) convinced that these can be used to reliably separate smaller E.gentianaeana from the other species without confirmation by dissection. Males of E.marginana are distinct in having a white hindwing.
Male genitalia: In E.gentianaeana and E.oblongana the aedeagus is without cornuti, in E.marginana the aedeagus has (~9 short stout) cornuti. In all three species there is a spined ventral extension of the sacculus; in E.gentianaeana and E.oblongana this extension is at ~1/3 of the sacculus/valva complex so that the valva beyond the extension is relatively long, in E.marginana this extension is close to 1/2 of the sacculus/valva complex so that the valva beyond the extension appears relatively short. In E.oblongana the uncus is rounded; in E.gentianaeana the uncus is also rounded but it is indented (though one of the images labelled as E.gentianaeana at dissection group shows a rounded uncus without indentation); in E.marginana the uncus is flattened.
Female genitalia: In E.gentianaeana and E.oblongana the posterior margin of the ostium is pointed; in E.marginana it is rounded. Differences between E.gentianaeana and E.oblongana are not clearly described in Pierce & Metcalfe or clearly demonstrated at dissection group; possibly the ductus bursae is broader in E.oblongana.
Male genitalia: In E.gentianaeana and E.oblongana the aedeagus is without cornuti, in E.marginana the aedeagus has (~9 short stout) cornuti. In all three species there is a spined ventral extension of the sacculus; in E.gentianaeana and E.oblongana this extension is at ~1/3 of the sacculus/valva complex so that the valva beyond the extension is relatively long, in E.marginana this extension is close to 1/2 of the sacculus/valva complex so that the valva beyond the extension appears relatively short. In E.oblongana the uncus is rounded; in E.gentianaeana the uncus is also rounded but it is indented (though one of the images labelled as E.gentianaeana at dissection group shows a rounded uncus without indentation); in E.marginana the uncus is flattened.
Female genitalia: In E.gentianaeana and E.oblongana the posterior margin of the ostium is pointed; in E.marginana it is rounded. Differences between E.gentianaeana and E.oblongana are not clearly described in Pierce & Metcalfe or clearly demonstrated at dissection group; possibly the ductus bursae is broader in E.oblongana.
Dissection
Male genitalia
Female genitalia
§1 Foulness, Essex; 08/08/2010; male; fw 7.9mm
§2 Foulness, Essex; 15/08/2010; female; fw 8.2mm
§3 Foulness, Essex; 05/08/2012; fw 7.9mm; male
§4 Foulness, Essex; 20/07/2013
§5 Foulness, Essex; 28/05/2016; male
§6 Foulness, Essex; 26/08/2017; female; fw 8.8mm
All images © Chris Lewis
§2 Foulness, Essex; 15/08/2010; female; fw 8.2mm
§3 Foulness, Essex; 05/08/2012; fw 7.9mm; male
§4 Foulness, Essex; 20/07/2013
§5 Foulness, Essex; 28/05/2016; male
§6 Foulness, Essex; 26/08/2017; female; fw 8.8mm
All images © Chris Lewis
Page published 09/01/2013 (§1-2) | §3 added 03/02/2013 | §4 added 09/11/2013 | §5 added 13/05/2017