About Papilio karna Felder & Felder, 1864
Papilio karna Felder & Felder, 1865 is a swallowtail butterfly species larger than the Malayan forms of the related species Papilio paris. For forewings of this species, as far as is currently known, there is at most only a faint hint of a green band just before the hindmargin. On the hindwing, the metallic region is nearly always separated from the wing cell, and it is broader toward the posterior end than in Papilio paris forms, making it even more distinctly band-shaped than in Papilio paris gedeensis. The red anal ring of the hindwing is very large, and the grey scales placed before the distal margin are condensed into clearer submarginal patches than they are in Papilio paris. On the underside of the hindwing, the submarginal spots are reddish yellow, with the three central spots reduced in size; the purple arcs on the underside are large, and the yellowish grey dusting covering both wings covers a smaller area than in related species. Females have an additional yellow submarginal spot on the upper surface of the hindwing, located behind the costal vein. The early life stages of Papilio karna have not been documented. This butterfly is found on the islands of Java, Sumatra, and Borneo, and it is much rarer than Papilio paris forms. Papilio karna holds the same relationship to Papilio paris that Papilio iswara holds to Papilio helenus. Three known geographical forms of Papilio karna are recognized. The first is the nominate form Papilio karna karna Fldr. (35 b), which is the smallest of the three forms. It occurs in West Java, in the same regions where Papilio paris gedeensis flies. The second form is Papilio karna discordia Nicev. (= discoidea Nicev.), which is larger than the nominate P. k. karna, and has smaller central reddish yellow submarginal spots on the underside of the hindwing. It is found in the Gajo highlands of North-East Sumatra. The third form is Papilio karna carnatus Rothsch. (= karnata Fruhst.) (35 a), which is native to North Borneo. This form appears to be much less rare than the other two Papilio karna forms, and it can also be found in lowland plains. Most individuals are the same size as P. k. discordia, though many specimens are no larger than the nominate P. k. karna. In P. k. carnatus, the inner margin of the metallic hindwing area between the subcostal vein and the first radial vein is very oblique, the yellowish green submarginal spots are very large, the reddish yellow submarginal spots on the underside of the hindwing are reduced, and the fifth of these spots is nearly always absent entirely.
