Species very similar to Citrogramma marissa, with black facial vitta and 2nd costal cell bare. C. pendleburyi differs in having wing much more microtrichose basally (only cell CuP bare on anterior margin) and a slightly broader eye angle (about 110°). C. marissa is only known from southern India and it is smaller than C. pendleburyi. Another morphological difference are the shape of yellow maculae on 2nd tergum and the size of dark scutellar macula, much broader and more rounded in C. marissa.
Adapted from original description (Curran 1928).
Scutum greenish-grey on the disc, surrounded by opaque black, the lateral margins and border of the scutellum pale yellowish; face with median black vitta; eyes bare; abdomen with two entire and two interrupted yellow fasciae. In the sense erroneously adopted by authors, this species would belong to Xanthogramma, a genus which is abundantly distinct in general appearance, but difficult to define. I know of only four species of Xanthogramma in the strict sense.
Head: Face and broad frontal orbits pale yellowish, the oral margin more orange, the broad median vitta, gena, and a large macula above the antennae shining black. Face and gena with fine white pile, the dorsal angles and the front black pilose; sides of face white pollinose. Face rather puffed, in profile the whole middle part rather swollen, leaving a shallow concavity above, below the swelling strongly retreating to the oral margin but the oral tip itself is slightly produced. Front broad, swollen, its sides slightly convex, the dorsal portion of the black part yellow, of the pale part, yellowish pollinose. Vertical triangle but slightly longer than broad, metallic green in ground colour but rather densely brownish-yellow pollinose. The eyes touch for a distance almost equal to the length of this triangle. Occiput greyish-yellow pollinose, broadly silvery pollinose along the orbits except above, with whitish and pure white pile. Antennae small, brownish, basoflagellomere reddish below, rectangularly oval, not twice as long as wide. Arista brown, tapering on the basal two-thirds.
Thorax: Lateral margins of the scutum whitish-yellow, the ground colour elsewhere bright metallic blue, but almost wholly concealed. The disc, except behind, is peculiarly greenish-grey pollinose, bordered on either side by a broad opaque black vitta; on either side of the middle line, diverging behind, a moderately broad, dark vitta; posterior of the scutum without such sheen. Pile fairly long, not very abundant, mostly yellow. Pleura metallic blue, thinly pale pollinose, with yellowish-white maculae as follows: a small one above the procoxae, posterior third of the anepisternum, a transverse, broad vitta on the dorsal part of the katepisternum and a broad, oblique fascia behind the root of the wing, the pile all pale yellow. Scutellum broadly bordered with dull yellowish-white, which leaves a large basal brownish triangle, which has an almost black middle, the pile all black, longer apically. Legs: Metalegs deep brown; profemora with the basal fourth or more brown and each with a brownish dash beyond the middle behind, and the tarsi brownish, the legs elsewhere yellowish-red although the tibiae are somewhat darker on the median portion. Pile whitish; black on the tarsi, metatibiae and apical half of all the femora. Wings hyaline; stigma luteous. Calypter pallidly yellow, except outwardly, with brown border and fringe. Halteres yellow.
Abdomen opaque black; broad sides of the second segment, almost to the middle, from which point a broad, elongate arm extends obliquely inwardly to the lateral apical third of the segment, pale yellow; these arms are widened somewhat before their ends, are rounded apically and separated from each other by almost the length of one arm. Practically all the fascia on the third segment lies before the middle; it is concave on either side anteriorly and convex behind, broadly separated from the base of the segment but reaching forward to the anterior angles at the sides. The fascia on the fourth segment is quite similar but it is narrower in the middle and less convex towards the sides behind. Fifth segment with the base almost entirely, and a large, broad apical triangle which reaches forward almost to join the basal fascia, black, the segment elsewhere pale yellow. The abdominal pile is yellow on the base as far as the posterior edge of the yellow spots on the second segment, from thence, all black.
Body lenght: 9.5 mm.
Holotype collected in Malaysia: Pahang State, Taman Negara National Park, Mount Tahan, 5460 ft.