LETHITES Scudder.
Satyrites Scudd. (nee Blanch.-Brullé), Rev. et Mag. de Zool., 1871-72, 66.
The costal border of the fore wing ([Pl. I], fig. 5) is gently and equably curved, the apex moderately acute but well rounded, the outer margin, except at its extremities, nearly straight, and the inner border straight or almost so; the outer border is a little shorter than the inner and about three-fifths the length of the costal margin.
The costal nervule terminates slightly beyond the middle of the costal margin, its basal two-fifths presenting a considerable and almost uniform expansion, which tapers rather rapidly at the tip, and reaches nearly to the middle of the upper border of the cell. The subcostal nervule is very slight on the basal half of the wing, closely connected with the posterior surface of the swollen portion of the costal nervure and only divaricating from that vein after the latter has lost its tumidity; it emits its first superior nervule at slightly more than three-fifths the distance from the tip of the bulbous portion of the costal nervure to the upper apex of the cell; its second at midway between the origin of the first and the tip of the cell; its third at midway between the upper apex of the cell and the origin of the fourth, which arises at about two-fifths the distance from the base of the third to the outer border of the wing. The first superior nervule terminates near the middle of the outer two-thirds of the costal border, the second midway between the apex of the first and third; the third terminates just above, and the fourth at or scarcely below, the tip of the wing. The first inferior subcostal nervule arises at a very short distance beyond the base of the second superior nervule, and curving rather strongly, terminates in the middle of the upper half of the outer border; the second inferior nervule is emitted from the first inferior as far beyond the base of the latter as that is beyond the base of the second superior nervule; at its origin it is directed inward as well as backward (forming the upper termination of the cell) and passes backward in a small, narrow and rather strongly curved bow, bent below more than above, beyond which it assumes a course nearly parallel to the first inferior nervule; just beyond the arcuate portion it is connected by a rather long, straight, oblique nervule, directed considerably outward as well as downward, to the origin of the upper median nervule. The median nervule is slightly enlarged at the base, and diminishes gradually and regularly in size to its first divarication, which is scarcely beyond the middle of the cell; the origin of its middle branch is slightly nearer the origin of the basal than of the terminal nervule; the latter strikes the middle of the outer border. The submedian nervure is straight and not swollen at the base. The cell is three times as long as broad, and scarcely more than half as long as the wing.
The article from which the above is quoted, as originally written, closes thus:
“The neuration of the fore wing does not seem to me to accord sufficiently with that of any known genus of Oreades to admit of its being classed with them. It undoubtedly has close affinities with the characters of the genus Debis (= Lethe Hübn.) as laid down by Westwood and Hewitson, if we exclude therefrom, as we should, the Papilio Portlandia of Fabricius. It is not a little interesting to notice that these authors have arranged this group in immediate proximity to the genus Cyllo (= Melanitis Fabr.), in which Dr. Boisduval placed the fossil species from Aix, named by him sepulta. Nor is it less interesting to find that in both genera all the living representatives (even including those discovered since the publication of the ‘Genera of Diurnal Lepidoptera’) are natives of the East Indies; so that the fossil butterflies of Provence have their nearest living allies in the far East.”
Although differing from Neorina ([Pl. II], fig. 8) very strikingly in the form of the wing and the swollen base of the costal nervure, this genus has some striking points of agreement with that in the neuration of the fore wing. The nervure closing the cell indeed is straight in Lethites and strongly curved in Neorina, but, as there, two of the superior subcostal nervules arise before the tip of the cell, and the other two are thrown off at about equal distances between the apex of the cell and of the wing; the vein closing the cell meets the median nervure in both cases as far beyond its second divarication as that is beyond the first; the shape and proportionate length of the cell is nearly the same in the two, but the costal nervure appears to be much shorter in Lethites.
With Lethe ([Pl. II], fig. 6) and Debis ([Pl. II]. fig. 10) the fossil genus can better be compared, as far as the form of the wing, the dilated costal vein, and the position and direction of the straight vein closing the cell are concerned; but in both these genera only a single superior subcostal nervule is emitted before the apex of the cell; the form of the cell again shows rather closer affinity between Lethites and these genera, although the difference in these respects is but slight. It is by no means distantly related to Enodia, in which two subcostal nervules are emitted before the tip of the cell, but differs from it in the much greater and more abrupt swelling of the costal vein, and in the much greater distance beyond the second divarication of the median nervure at which the vein closing the cell meets this nervure. It even exhibits no small affinity to Cercyonis, and especially to those species in which there is little dilation of the median nervure; the costal nervure is swollen in precisely the same way, and the superior nervules of the subcostal nervure are much the same; but the form of the wing is strikingly different, and the lowest subcostal interspace much wider at the base, in comparison with the width of the base of the subcosto-median interspace, in Cercyonis than in Lethites; and this seems to be a character of considerable importance. It may be noted in this connection that the markings of the fossil must have closely resembled Cercyonis Pegala.
Its nearest ally among living European types would seem to be Maniola Hermione, in which the costal and median veins are about equally swollen. The neuration of Lethites agrees with this genus in much the same way as it does with Cercyonis, the comparative width of the interspaces beyond the cell being very different in the living genera from what it is in the fossil. In the form of the wing Maniola agrees much better with Lethites than Cercyonis does, but the costa is much more arched, and the cell is much the longer in Maniola; were there no obscure spot in the lower median interspace in the male of M. Hermione, the markings of the fossil would agree with it almost perfectly.