Zygaena purpuralis
Introduction '''''Zygaena purpuralis''''', the '''transparent burnet''',  is a moth of the family Zygaenidae. ''Zygaena purpuralis''. Illustration from Europas bekannteste Schmetterlinge, Plate IX (c. 1895)
Description ''Zygaena purpuralis'' is a medium-sized moth with a wingspan reaching . Usually the forewings show three bright red longitudinal streaks quite variable in shape, with almost transparent greyish-bluish edges. Hindwings are more extensively or almost completely bright red. Head and thorax are black, while the abdomen is dark blue. Larvae are yellow, with some lines of small black spots.
Technical description and variation (Seitz) ''Z. purpuralis'' Brunnich (= ''pilosellae'' Esp. ; ''minos'' Fuessl.). In this species the hindmargin of the forewing (base included) is all black, while the red wedge-spots situated before it may be shaped entirely as in ''erythrus'' Hbn. An aberration with light yellow instead of red markings, already recorded by Ochsenheimer, has more lately been named by Ruhl ab. ''grossmanni'' (= ''lutescens'' Tutt). It is said to have been observed as a constant or at least prevalent form in certain very limited localities. In ab. ''obscura'' Tutt  the entire wings, inclusive of the red colour, is darkened. — ''sareptensis'' Stgr.-Reb. now ''Zygaena minos'' ssp. ''sareptensis'' Rebel, 1901  is a large, somewhat paler, lighter red form from South Russia. — ''diaphana'' Stgr.now ''Zygaena minos'' ssp. ''diaphana'' Staudinger, 1887  , from Tauria, has thinly scaled, strongly transparent wings, the central wedge-spot being distally strongly widened. — ''nubigena'' Led. subspecies  is also a very thinly scaled form from the high mountains of Europe and Asia, having moreover (like many mountain-forms) a very shaggy body, like ''Zygaena exulans'', with which it occurs occasionally together. — In the rather large form ''smirnovi'' Christ. now ''Zygaena minos'' ssp. ''smirnovi'' Christoph, 1884 , from Turkestan, the distal wedge-spot is constricted before its dilated apex. — ''pluto'' O. (= ''pythia'' Hbn.) synonym of ''Z.purpuralis'' has a black apex to the hindwing and the central streak of forewing is entirely of even width, not in the least being dilated distally; in South Europe, as far north as Austria. — In ''polygalae'' Esp. now ''Zygaena filipendulae'' ssp. ''polygalae'' Esper, 1783  the black interspaces between the red streaks have entirely disappeared the red being so extended (especially in females) that the forewing is only edged with black, differing from ''Zygaena rubicundus'' in the hindmargin of forewing being black (though sometimes only narrowly); in the South, especially Northern Italy. — In ''heringi'' Zell. synonym of ''purpuralis'' , from North Germany, the antenna is thinner and the central wedge-spot of the somewhat broader forewing extends to near the distal edge. — In ab. ''interrupta'' Stgr. synonym for ''Zygaena minos'' ssp. ''pimpinellae''   the central streak is broadly interrupted and the posterior one often constricted in middle; more in the North of the area, among the name-typical form. — If all three streaks are interrupted, the red is separated into 6 spots, recalling the pattern of other Zygaenas; this form is ab. ''sexmaculata'' Burgeff. — Finally, there occur also specimens which have a red abdominal belt: ab. ''cingulata'' Burgeff — Larva bluish white or light yellow; a subdorsal row of heavy black dots; head, pectoral legs and stigmata black.Figs. Figs. 4a  ''Anthrocera minos'' var. ''nubigena'' = ''Zygaena purpuralis'' (Brünnich, 1763) larvae before last moult 4 larvae after last moult
Biology Adult moths are on wing from late May until August, depending on location. They fly during the day, especially with warm and sunny weather, feeding on nectar of various flowers.The larvae feed on wild thyme (''Thymus polytrichus'', ''Thymus serpyllum'', etc.). They occur from August to May and overwinter once or twice.
Distribution This species can be is found in most of western, central and southern Europe, from Ireland to France through to Asia Minor, the Caucasus, Russia and across the Palearctic to the Altai Mountains.
Habitat ''Zygaena purpuralis'' prefers sunny and grassy slopes, under cliffs and dry grassland.
Subspecies There are several distinct sub-species:*''Zygaena purpuralis purpuralis''*''Zygaena purpuralis austronubigena'' Verity 1946*''Zygaena purpuralis caledonensis'' Reiss, 1931 (Hebridean islands of Skye, Lismore, Kerrera, Mull, Ulva, Eigg, Canna, and Rùm and in a few localities on the Scottish mainland in Kintyre and parts of western Argyllshire)*''Zygaena purpuralis dojranica'' Burgeff, 1926*''Zygaena purpuralis fiorii'' Costantini, 1916*''Zygaena purpuralis isarca'' Verity, 1922*''Zygaena purpuralis lathyri'' Boisduval, 1828*''Zygaena purpuralis magnalpina'' Verity, 1922*''Zygaena purpuralis mirabilis'' Verity, 1922*''Zygaena purpuralis nubigena'' Lederer, 1853*''Zygaena purpuralis sabulosa'' Tremewan, 1976 (western Ireland in the Burren, Counties Galway and Mayo and on Inishmore, in the Aran Islands)*''Zygaena purpuralis segontii'' Tremewan, 1958 (occurred on sea-cliffs of the Llŷn Peninsula, Caernarvonshire. It has not been reported since 1962 and might be extinct)
References
External links * * *  Transparent burnet on UKmoths*  Butterfly Conservation*  Fauna Europaea*  Lepiforum.de*  Schmetterling-raupe.de