Megalographa biloba (Stephens)

Lafontaine, J. Donald & Sullivan, J. Bolling, 2009, A review of the genus Megalographa Lafontaine and Poole (Lepidoptera: Noctuidae: Plusiinae) with the description of a new species from Costa Rica, Insecta Mundi 2009 (77), pp. 1-10 : 6-7

Megalographa biloba (Stephens)

( Figure 6 , 12 , 17 )

Plusia biloba Stephens 1830: 104 . Type: male, BMNH, London [examined]; Type locality: unknown. Note : The species was nominally described from England, where it occurs occasionally as a fall migrant from North America , but Stephens was also known to have mixed North American material in with European material in error .

Diagnosis. Megalographa biloba was thoroughly characterized by Lafontaine and Poole (1991) with adults and genitalia figured. It differs from M. talamanca in several aspects. In the region where M. talamanca was collected, three M. biloba were taken at lower altitudes (2200–2600m). These M. biloba are smaller (male wing length: 14.1mm; female wing length: 15.6mm) and the silver hemispheres of the stigma are joined. The postmedian line is notched between M3 and CUA 1 in M. biloba ; in M. talamanca there is a defined dash. The silver crescent below the reniform spot is entire and prominent in M. biloba but often broken and indistinct in M. talamanca . In the male genitalia the clavus is approximately the length of the clasper in M. biloba but 0.25X its length in M. talamanca ( M. biloba clasper (0.31mm) and clavus (0.31mm); M. talamanca clasper (0.50mm) and clavus (0.13mm). The subbasal evagination in the vesica is larger in M. biloba . In the female genitalia, the ductus bursae is 0.25X as long as the corpus bursae, whereas in M. talamanca it is 0.13X as long, and the corpus bursae has a mesial twist where the bursa bends through a 90 o angle that is absent in M. talamanca .

Distribution and Habitat. Megalographa biloba is widely distributed from southern United States southward through Central and South America to Argentina. It occurs farther north into northern United States and southern Canada as a seasonal migrant where it usually produces one or two generations each summer, but it rarely survives the winter in the northern part of its range. It also occurs in the Hawaiian Islands but it is unknown if the species occurs there naturally or was introduced. The species also occurs as a rare migrant in Great Britain, mainly in the summer and fall, but its travel to Europe could be aided by ships crossing the Atlantic.

Figures

Figure 1–8. Megalographa spp. 1) M. monoxyla, m, Cochabamba, Incachaca, Bolivia. 2) M. agualaniata, m, Cochabamba, Incachaca, Bolivia. 3) M. culminicola, m, Ecuador. 4) M. culminicola, f, Junin to Huanuco Hwy., Pasco, Peru, 3600 m. 5) M. bonaerensis, m, Curitiba, 920 m, Paraná, Brazil. 6) M. biloba, m, San Gerardo de Dota, Cartago, Costa Rica. 7-8) M. talamanca, m, Reserva los Nimbulos, 3150 m, Cerro de la Muerte, San José, Costa Rica.

Figure 9–14. Male genitalia of Megalographa spp. and Lophoplusia sp. 9) M. monoxyla, Cochabamba, Incachaca, Bolivia. 10) M. agualaniata, Venezuela. 11) M. bonaerensis, Curitiba, 920 m, Paraná, Brazil. 12) M. biloba, Verdugo, California. 13) M. talamanca, Reserva los Nimbulos, 3150 m, Cerro de la Muerte, San José, Costa Rica. 14) Lophoplusia sp., Kauai, Hawaii.

Figure 15–18. Female genitalia of Megalographa spp. 15) M. agualaniata, Bolivia. 16) M. bonaerensis, Curitiba, 920 m, Paraná, Brazil. 17) M. biloba, Thunder Bay, Ontario, Canada. 18) M. talamanca, Reserva los Nimbulos, 3150 m, Cerro de la Muerte, San José, Costa Rica.