Hemming (1967) stated:-
Evans (1.c. : 180) pointed out that Hübner had figured two species under the name Anastrus obscures, figs 1/2, which Hübner considered to be the male, belonging to one species, and figs 3 and 4, which Hübner considered to be the female, being in reality the male of a second species. Evans went on to say that Watson in 1893 - the reference presumably being to Watson, 1893, Proc. zool. Soc. Lond. 1893 : 43, 54 - had selected "the second species (figs 3 and 4) as representing obscures and as the type of the genus [Anastrus]". This does not appear to be correct ; all that Watson seems to have done was to base his diagnosis of Anastrus upon Anastrus obscures, as interpreted by Hübner's figs 3 and 4, without commenting on the composite nature of the nominal species Anastrus obscurus as established by Hübner. Watson cannot therefore be accepted as having established the interpretation of this nominal species. Evans however quite definitely selected the species figured as Anastrus obscurus in figs 3 & 4 on Hübner's plate (pl. ) as that to which the above name should adhere, to the exclusion of the species figured by Hübner under the same name in figs 1 and 2 on the same plate. Evans in this passage was the first author to make an effective lectotype selection for the nominal species Anastrus obscures Hübner, the lectotype so selected being the male specimen figured (erroneously as a female) by Hübner in figs 3 and 4 on the plate referred to above. Evans added that, in his opinion, the taxon figured by Hübner as Anastrus obscures in figs 1 and 2 of the above plate was that represented by the nominal species Papilio philemon Fabricius, 1775 (Syst. Ent. : 534), placed by Evans (1.c. : 203) in the genus Ephyriades Hübner, .
The higher classification used here follows Lamas (2008).
Learn more about Hesperiidae in Wikipedia.
See images at Butterflies of America where it is treated in the Pyrrginae: Erynnini.
Search the Biodiversity Heritage Library (BHL) for references to ANASTRUS and included species.