An unusual Polyommatus thersites with basal black spots on FW underside (Lepidoptera: Lycaenidae, Polyommatiti)

2012·0.78 MB·English

by  Harry Van Oorschot

An unusual Polyommatus thersites with basal black spots on FW
underside (Lepidoptera: Lycaenidae, Polyommatiti)
HarryvanOorschot&JohnG.Coutsis
Abstract.AmalePolyommatusthersites\withbasalblackspotsonltsFWundersideisreportedforthefirsttime,andthe
meritsofdifferentiatingthisspeciesfromthesimilarP. icarussolelyonthebasisoftheexistenceornotofthesespotsare
questioned.
Samenvatting.EenmannetjePolyommatusthersitesmetbasale,zwartevlekkenopdeonderkantvandevoorvleugelwordt
voorheteerstgemeld,endemogelijkhedenomdezesoortteonderscheidenvandegelijkendeP.icarusenkelgebaseerdopde
aanwezigheidvandezevlekkenwordtbesproken.
Résumé. UnmaledePolyommatusthersitespossédantdestachesbasalesnoiressurIedessousdesailesantérieuresest
signaléicipourlapremièrefois.Lapossibilitédedistinguercetteespècedel'espècesimilaireP.icarus,ensebasantseulement
surl'existencedecestachesestdiscutée.
Keywords:Lycaenidae-Polyommatiti-Polyommatus-thersites-icarus-malegenitalia-Spain.
VanOorschotH.:NCBNaturalis,NL-2300RALeiden,[email protected]
CoutsisJ.G.:4GlykonosStreet,GR-10675Athens,[email protected]
Introduction AnunusualP. thersitesfromSpain
So far, one of the ways by which Polyommatus Lately we obtained a male Polyommatus specimen
thersites (Cantener, 1835) had been differentiated from from PontdeSuert,in Lerida,Spain,thatforall practical
the similar looking Polyommatus icarus (Rottemburg, purposeslooked likeaP. icarus, havingtwowell-defined
1775) was by the total absence in the former of two basal blackspotson its left FW undersideand onesuch
black basal spots on FW underside, and the usual spot on its right FW underside (Fig. 1). Flowever, the
presence in the latter of these spots. In rare cases in faintlyvisibleFWuppersideandroconial hairs,presentin
which P. icarus lacked them, differentiation ofthe two P. thersites, but always absent in P. icarus, led us to
taxa could safely be achieved by easily detectable wander about its true identity. Upon dissection, its
differencesin both maleandfemalegenitalia. Ingeneral genitalia (Fig. 2)werefoundto havean aedeaguswitha
it was assumed that P. thersites always lacked the FW bulbousdistal end [in P. icarus it isslenderand straight
underside basal black spots, and that specimens (Fig. 3)], provingbeyond doubtthatthiswasindeeda P.
possessing them should necessarily be considered as thersites, and mostcertainlythefirstoneever reported
beingP.icarus. ofitskind.
Fig.1.Polyommatusthersites(Cantener,1835).Spain,Lerida,Pontde
Suert,900m,15.vii.1974.-a.Upperside,b.Underside.
Phegea40(la)Ol.iii.2012:3
Fig.2.Polyommatusthersites
(Cantener,1835).Spain,
Lerida,PontdeSuert,900m,
15.vii.1974.Prep.No.4544.
Genitaliccomponents.-a.
Lateralaspectofouterfaceof
leftvalve;b.Dorsalaspectof
aedeagus;c.Lateralaspectof
leftsideofgenitalia,with
valvaeandaedeagusomitted;
d.Ventralaspectofrighthalf
oftegumentogetherwithright
labisandfalx.
Fig.3.Polyommatusicarus
(Rottemburg,1775).Spain,
Albacete,Riopar,1200m,25-
26.vi.l995.Prep.No.2672.
Genitaliccomponents.-a.
Lateralaspectofouterfaceof
leftvalve;b.Dorsalaspectof
aedeagus;c.Lateralaspectof
leftsideofgenitalia,with
valvaeandaedeagusomitted;
d.Ventralaspectofrighthalf
oftegumentogetherwithright
labisandfalx.
Conclusions genitalia. In the males in particular, differentiating the
two taxa solely by reference to the FW upperside
Thisrecentfindsuggeststhattheonlyfool-proofway androconial hairs applies mostly to fresh specimens, as
toalwaysdifferentiatebothmaleandfemaleP. thersites these hairs are often difficult to detect in worn P.
from P. icarus is by reference to their respective thersites.
Phegea40(la)01.iii.2012:4