Crambodes talidiformis Guenée 1852

Crambodes talidiformis Guenée, 1852, Histoire Naturelle des Insectes. Species General des Lepidopteres, 6:152, pl. 7, fig. 12.

Carvanca conjungens Walker, 1858, List of the Specimens of Lepidopterous Insects in the Collection of the British Museum, 15:1661.

Diagnosis: Crambodes talidiformis has an elongate forewing. The general appearance of the forewing is a striate, woody brown. The reniform spot is a white streak and there are black streaks on the radial veins in the postmedial and subterminal regions. The antemedial in highly scallped with dark streaking on the veins. The postmedial line is obscure, but when visible consists of two parallel lines of dark dots. The hindwing of the male is white or yellowish, but the female is suffused with light brown. The male antenna are strongly serrate with tufts of long bristles from the serrations. This species is most likely to be confused with Condica discistriga and C. temecula. Luckily the ranges of the two species are almost allopatric except in the southwestern United States. The serrate antenna of both males and females are an obvious differentiating factor and clearly the male and female genitalia are not even remotely similar.

Distribution: This species has a peculiar distribution that mimics the distribution of the other known Verbena feeder in North America, Catabena lineolata. The species occurs through the northern half of eastern North America and ranges westward through Michigan, Wisconsin, Iowa, Illinois and Nebraska. The distribution then dips southward through Texas and south into most of Mexico. The species also ranges westward into eastern Arizona. The species is absent from most of the southeastern United States except for western Mississippi and Louisiana. Its absence (and the absence of Catabena lineoata) from most of the southeastern United States is something of mystery to me. Certainly several species of Verbena occur there. No specific species of Verbena have been listed as foodplants. Possibly both species are restricted to one or a specific group of species in the genus that does not occur in the southeastern United States. Clearly this distributional pattern should be investigated. The species is sexually dimorphic, but not strongly so. The male antenna is strongly serrate, but the female antenna is simple. Females tend to be darker than males and the hindwing of the female is suffused with light brown while that of the male is white or yellowish. The species varies somewhat in size but size does not seem to be geographically determined. Perhaps foodplant quality is involved.

Adults occur throughout the summer further north with the flight period becoming longer the further south one goes. In Texas the species appears to be commoner in the spring and fall than during the summer months.

Identification Quality: Excellent

Larva: The larva has been described by Crumb (1956) and has been reared from Verbena. The larva is somewhat thin and elongate with the first pair of abdominal prolegs slightly reduced in size relative to the next three pairs. The larva belongs to Crumb's "larva confluentae" group and there are only two SV setae on abdominal segment one. The larva is basically green and its major feature is a red line running through the spiracles. There is a vague white middorsal line margined with red, particularly near the cephalad margin of each abdominal segment. The head is light brown or green (cannot tell in preserved material) with a vague darker brown reticulation. For more detail, see Crumb (1956).

Foodplants: Verbena.

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