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Urbanus viterboana (Ehrmann, 1907)
(Bluish Longtail)

Type Specimens
photo collection:

Pinned Specimens
photo collection Page 1:

Pinned Specimens
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Live Adults
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Immatures photo collection
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Immatures photo collection
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Genitalia photo collection:

Distribution and Larval Foodplants:

E & W Mexico to Colombia and Ecuador




Text from:

Steinhauser, Stephen Rogers 1981. A revision of the proteus group of the genus Urbanus Hübner. Lepidoptera: Hesperiidae. Bulletin of the Allyn Museum 62: 1-41, 61 figs. (4 September).

p. 14-16, f. 7, 8, 34, 49

Urbanua viterboana (Ehrmann), 1907

Figures 7 (♂), 8 (♀), 34 (♂ genitalia), 49 (♀ genitalia)

Thymele viterboana Ehrmann, 1907: 321. Type locality Colombia: Socorro, type in CM.  

The ♂ forewing has a costal fold. In both sexes, the forewing bears the usual  
complement of hyaline spots, those in the ♀ generally larger than in the ♂. Either sex  
may have a subapical spot in M2-M3 but seldom in M1-M2. The subapical spots are not  
present in the holotype. The upper surface basal hair scale clothing is bright blue,  
occasionally with a green tint. On the hindwing this basal clothing is sharply defined  
distally. The under surface ground color varies from a medium brown (holotype) to a  
dark purple gray. The under hindwing central band is entire; the subcostal spots may  
be conjoined resulting in a widening of the band at the costa, or separate, making the  
band bifurcate. A few individuals exhibit nearly complete separation of these spots not  
only from each other but also from the rest of the band. The postdiscal band is entire;  
the pale distal edging to the subtornal spot of this band and to the cell spot of the  
central band is very faint.

The hindwing fringe is white to pale brown and checkered dark brown at the vein  
ends; forewing fringe is only slightly paler than the ground color and faintly checkered,  
usually to the apex. The antennal club beneath is prominently darkened centrally.

A random sample of 15 ♂ and 13 ♀ specimens gave the following wing  
measurements: ♂ forewing averaged 23.4 mm from base to apex and 13.1 mm from  
costa to tornus, varying from 22 x 12 to 25 x 14 (holotype 25 x 13.5); average hindwing  
tail length 9 mm, varying from 7 to 10 (holotype 10 mm); ♀ forewing averaged 25.8 x  
14.5, varying from 23 x 13 to 28 x 16; average hindwing tail length 12 mm, varying from  
10 to 14.

In the ♂ genitalia, viewed ventrally, the uncus arms are narrowly separated, deeply  
divided and nearly parallel, diverging slightly towards the tips; the gnathos is slender,  
bluntly pointed. The valvae are symmetrical, long and relatively slender, the ampulla  
with a rounded shoulder caudally where it meets the cucullus, its dorsal margin  
sinuous. The cucullus has a moderately dentate dorsal area which may be dorsally more  
or less pointed, but usually rounded, just caudad of the ampulla and seldom projecting  
dorsad beyond the dorsal edge of the ampulla. The cucullus is very variable, more or  
less an isosceles triangle, sharply to bluntly pointed caudally and often with the dorsal  
edge more or less concave.

In the ♀ genitalia the terminal margins of the papillae anales are nearly straight; the  
anterior margin of the sterigma slightly concave centrally; the lamella postvaginalis  
has a deep central indentation caudally; the lamella antevaginalis is weakly sclerotized,  
its caudal margin with a broad shallow central concavity; the ductus bursae is short,  
tapered; corpus bursae long, bent to banana shape.

129 specimens were examined from the following countries: Mexico 35 ♂, 18 ♀;  
Guatemala 1 ♂, 2 ♀; El Salvador 10 ♂, 17 ♀; Costa Rica 6 ♂, 4 ♀; Panama 4 ♂, 3 ♀;  
Colombia 16 ♂, 6 ♂; Ecuador 7 ♂. 34 ♂ and 6 ♀ genitalia preparations were made and  
studied in addition to that of the holotype.

This is perhaps the most variable species in the proteus group. It and its close  
relatives, belli, dubius and pronta are clearly distinct entities, yet some individuals can  
be very difficult to place, suggesting that there may be considerable hybridizing  
between them. There is less chance of confusing viterboana with pronta than with belli  
and dubius because of the prominent division of the under hindwing band into separate  
spots. It can be distinguished from belli by the upper surface color being blue in  
viterboana and green in belli. The shape of the valvae is individually quite variable in  
both species, making separation of the males on the basis of genitalia alone rather  
difficult. However, when confronted with a blue-green individual, it usually can be  
determined with little doubt on the basis of the valvae; in viterboana the dorsal dentate  
area of the cucullus seldom projects dorsad beyond the dorsal edge of the ampulla,  
whereas in belli it usually does project dorsad. Females can be separated genitalically  
by the shape of the corpus bursae which is hooked like a letter "J" in belli and bent to a  
banana shape in viterboana. From dubius it can be distinguished superficially by the  
under hindwing distal pale edging to the cell and subtornal spots which are very faint in  
viterboana and prominent in dubius, and by the continuation of the postdiscal band to  
the costa in dubius but only to vein Rs in viterboana. Genitalically the males are  
difficult to separate, but the females can be distinguished, usually without dissection,  
by the shape of the caudal edge of the lamella postvaginalis which is a smooth, almost  
uninterrupted curve in dubius, but deeply indented centrally in viterboana.


Steinhauser, Stephen Rogers. 1981. A revision of the proteus group of the genus Urbanus Hübner. Lepidoptera: Hesperiidae. Bulletin of the Allyn Museum 62: 1-41, 61 figs. {4 September}. p. 14-16, f. 7, 8, 34, 49

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