Introduction
There are 1265 known neotropical species of Lycaenidae. The vast majority of these – 1058 – are allocated to Theclinae, while 120 are placed in Polyommatinae and 7 in Lycaeninae.
In 1990 Johnson erected the genus Penaincisalia, which he included in the Theclinae (hairstreaks). For various reasons during the course of 1992 he renamed the genus several times, thus it has also been known as Thecloxurina, Abloxurina, Pos and Candora. These names were all declared invalid however, and all but one of the species were reverted to Penaincisalia. The other species planuma created a problem. It was discovered that its holotype had 4 radial veins on the forewing, whereas all other Eumaeines have only three. Consequently in 2004 Robbins transferred this species to the Polyommatinae.
Penaincisalia comprises of 60 small inconspicuous insects, most of which inhabit the transition zone between the elfin cloudforests and dry plateaux of the Andes. The males of most species including descimoni have a purple or blue iridescence on the uppersides, although some such as aurulenta have a coppery sheen instead. In females the iridescence is greatly reduced or absent, revealing the earthy brown ground colour.
The undersides vary according to species but are always cryptic. Some species are marked so they resemble a dead leaf. Others including descimoni have a dirty ochreous ground colour, with a series of brown median and submarginal marks, enabling them to blend perfectly against the boulders on which they frequently settle.
The wing shape is highly variable from one species to another – e.g. descimoni and biophot have very rounded wings, whereas in loxurina, tegulina and atymna the forewing apex is acute, and the hindwings are extended to form tails reminiscent of the Oriental genus Loxura.
Penaincisalia descimoni was first discovered by Descimon in 1986 at Catac on the Cordillera Blanca in Peru, and was formerly described by Johnson in 1990. Its precise distribution is unknown, but it is likely to be restricted to a relatively small area of Peru.
Habitats
This species is found in elfin forest, and on barren rocky grassland plateaux, at altitudes between 1500-3000m. The illustrated example was found between La Oroya and San Mateo, on the western slopes of the Andes, at an elevation of about 2000m.
Lifecycle
To be completed.
Adult behaviour
The butterflies are usually encountered as small colonies. Males can be found perched at the apex of large boulders, which they presumably use as territorial outlooks, from which they survey and intercept passing females.