Spodoptera exigiia (Hiibner)

Spodoptera exigiia (Hiibner)
Figs. 18, 25, 38, 47, 59, 68, 77, 85, 95, 105, 116, 124, 151-152, 172-180, 308, 338, 370, 402, 434, 471-473, 522
Noctua exigiia Hiibner 1808: plate 78, figure 362. Noctua fulgens Geyer 1832: plate 168, figure 796. Caradrina pygmaea Rambur 1834: 384, plate 8, figure 2;
Walker 1856: 188. Caradrina junceti Zeller 1847: 447. Laphygma caradrinoides Walker 1856: 190. Caradrina flavimacidata Harvey 1876: 54. Caradrina sebghana Austaut 1880: 212. Caradrina venosa Butler 1880a: 7. Prodenia caradrinoides; Cotes & Swinhoe 1888: 326. Laphygma flavimaculata; Smith 1893: 168; Grote 1895: 42;
Hampson 1909: 264. Laphygma exigiia; Walker 1856: 188; Cotes & Swinhoe
1888: 327; Swinhoe 1890: 227. Hampson 1909: 265;
Warren in Seitz 1914a: 322; Barnes & McDunnough
1917: 67; Draudt 1926: 256; McDunnough 1938: 96. Laphygma exigua subsp. antipodea Warren in Seitz, 1914a: Spodoptera exigua; Boursin 1964: 238; Forster &
Wohlfahrt 1971: 159; Brown & Dewhurst 1975: 245;
Franclemont & Todd 1983: 141; Todd & Poole 1980:
726; Goater 1983: 275; Poole 1989: 923; Edwards
1996: 324; Poole & Gentili 1996: 774; Kononenko et
al. 1998: 233.
Douzdrina protector de Laever 1985: 149; [synonymized byYelal985]:212.
Diagnosis. — This is a small moth with forewing ground color light brown to pale gray, a round, cream, orbicular spot centered with pale rufous, and hindwing with veins covered with light brown scales to base (Figs. 172-180). Spodoptera exigiia has a cosmopolitan distribution. In the New World the female of S.frugiperda is most similar, but S. exigua can be distinguished by the lack of brown scales on veins at base of hindwing. In the male genitalia the cucullus has a round apex and sacculus is not well differentiated from valve
truncate apex and sacculus is well differentiated
has an elongate corpus bursa (Fig. 402), compared to S. frugiperda with a round corpus bursa (Fig. 417). In the Old World S. exigua can be confused with the female of S. cilium, which has a similar orbicular spot that can be completely cream or centered with buff to brown (Figs. 182, 184-185, 187-188), and S. pecten (Figs. 196, 198, 200, 202-203). The color of the hindwing veins can be used to separate S. exigua from either S. cilium or S. pecten which have white veins near the base. Female genitalia are most similar to S. pecten (Fig.
405), but the ductus bursae is much shorter in S. exigua.
Description. Adult Male. — Head: Basal segment of labial palpus cream, scales mixed with brown and black medially; median segment mixed with black and brown scales in basal half, cream apically; apical segment a mixture of cream, brown, and black scales. Frons with short scales cream; long scales cream to rufous; lateral spots at eye margin black; vertex cream (variably mixed with brown and black). Antenna filiform; scape cream and brown; flagellum cream (annulated brown becoming wholly brown at midlength).
Thorax: Patagium light brown mixed with white scales, brown along apical margin. Tegula brown. Mesothorax a mixture of brown and light brown scales. Underside of thorax white. Prothoracic femur fuscous and cream; tibia with lateral scale tufts not extending beyond first tarsal segment, cream and fuscous (sometimes rufous scales present), subapical spot absent; tarsal segments fuscous with cream apical rings. Mesothoracic femur fuscous and cream; tibia fuscous and cream, inner spur more than twice length of outer spur, mediolateral surface sparsely scaled on both spurs; tarsal segments fuscous with cream apical rings. Metathoracic femur fuscous and cream; tibia fuscous and cream; first tarsal segment cream, remainder as in other legs.
Forewing: Length, 11-14 mm; ground color light brown to cream; basal line absent; R vein not a contrasting color; basal scale patch between R and Cu veins absent; basal half circle scale patch below Cu vein absent; antemedial line black; claviform spot absent; basal scale patch absent; gray patch covering anal cell and half of cell CuA2 absent; oblique brown mark from fifth outer marginal spot to vein CuA2 absent; curved white line from antemedial line to postmedial line absentorbicular spot round, cream, with pale rufous center; reniform spot with cream border, center variable with a combination of rufous, light brown, and or black scales; white scales along Cu vein and bases of M3 and CuAl veins absent; postmedial line black, indistinct, from just below costa to posterior margin, wavy; postmedian band undifferentiated; black scale patches in middle of cells in postmedian area absent; subterminal line absent; apex lacking a white patch; black triangular-shaped spots along outer margin; fringe pale gray. Underside ground color a mix-
ture of light brown and white scales, a slightly darker area covering discal cell; outer margin with black spots; reniform spot absent.
Hindwing: Ground color white; apex, outer margin, and veins with light brown scales; fringe white. Underside ground color white; costal cells C and Sc cream speckled with pale gray scales; outer margin with gray triangular spots in middle of cells Sc to CuAl; no spot on underside.
Abdomen: Dorsum cream; venter cream; distolateral black spots on sternites; 8th tergite with spiculate patches absent on caudal margin.
Genitalia: Uncus curved in basal half; slender, gradually narrowing toward pointed apex; setae few or absent. Scaphium elongate, weakly developed. Tegumen lacking a pair of projecting arms on upper third. Costa bent in basal fifth (Figs. 308, 338). Costal process absent. Cucullus apex rounded; produced. Anellifer with lightly sclerotized plate bearing setae absent. Ampulla elongate, narrow, slightly curved, apex round; extends to just below apex of valve (Figs. 308, 338). Clasper proper absent. Clavus absent. Sacculus narrow, width less than 0.2 length, tapering distally; apex pointed. Valvula wider than valve; not differentiated from valve; indentation absent. Coremata moderately elongate, approximately 0.5 or less length of valve; no distinct lobes. Juxta a narrow elliptical band, median process narrow with grooved apex, ventral margin convex. Anellus with minute granules. Vinculum a broad U-shape with bowed arms and a robust base. Aedoeagus straight; coecum equal in diameter to shaft; patch of spines absent on apex of membranous sheath surrounding aedoeagus. Vesica curving ventrally; moderately elongate, 0.75-1.0 length of aedoeagus; apicobasal cornutal patch a narrow ribbon; short, extending to just beyond apex of aedoeagus; cornuti in form of minute flat granules; lateral cornutal patch absent; dense cornutal patch subapical on vesica; distal cornutus a large spine.
Adult Female. — Essentially as described for male except:
Forewing: Length, 12.5-14 mm.
Abdomen: Fine dense scales on 8th segment whitish.
Genitalia: Ventral plate of ostium bursa with height greater than width; distal margin straight; ventrolateral invaginated pocket of 8th sternite absent. Ductus bursae short (length less than twice width); completely sclerotized. Appendix bursae membranous. Corpus bursae elongate,
length greater than twice width; smooth. Signum in apical half of corpus bursae; elongate, length greater than 1.15 mm; forming less than a 30 degree angle to vertical axis of corpus bursae.
Larva. — See description, p. 99.
Type material. — Noctua exigua Hiibner. The specimen illustrated in Hiibner (1808, plate 78, figure 362) is a fair representation of S. exigua and the specimen the illustration depicts is considered the holotype. Type locality: Unknown.
Noctua fulgens Geyer. The type is apparently lost. Type locality: [Italy]: [Sicily].
Caradrina pygmaea Rambur. The type is apparently lost. Type locality: Marseille, France.
Caradrina junceti Zeller. The lectotype 8 [BMNH, here designated] is labeled: Zell. Coll. ,1884; Spain, Caralonia, 3-VII; junceti, var. b., Cat. 3 Ful; Noctuidae genitalia slide No. 3890 8 . The lectotype is designated to ensure nomenclatural stability in this confusing group of species and is illustrated in Fig. 179. Type locality: Caralonia, Spain. The following syntypes become paralectotypes: (1) 9, Label data: Zell. Coll.,1884; Spain, Caralonia, 3-VII; junceti 9 , Cat. 3 Ful; Noctuidae genitalia slide No. 3936 9. (2) 9, Label data: Zell. Coll.,1884; Spain, Caralonia, 3-VII; junceti 9, Cat. 3 Ful. (3) 8, Label data: Zell. Coll.,1884; junceti 8 , Cat. 3 Ful; Noctuidae genitalia slide No. 589 8 .
Laphygma caradrinoides Walker. The holotype 8 [BMNH] is labeled: C. Colony [South Africa], 406-26; Laphygma_ caradrinoides; Noctuidae genitalia slide No. 594 8. Type locality: C. Colony [South Africa].
Caradrina flavimaculata Harvey. The lectotype 8 (BMNH, here designated] is labeled: syntype 3481, Californ. [United States]; California, Grote Coll., Caradrina flavimaculata Harvey; Noctuidae genitalia slide No. 1598 8 . The lectotype is designated to ensure nomenclatural stability in this confusing group of species and is illustrated in Fig. 178. Type locality: California, United States of America.
Caradrina sebghana Austaut. The type is apparently lost. Type locality: Algeria.
Caradrina venosa Butler. The holotype 9 [BMNH] is labeled: Hawaii, Honolulu, T. Blackburn, 80-31; Caradrina venosa Butler type; Noctuidae genitalia slide No. 1658 9. Type locality: Honolulu, Hawaii, United States of America.
Laphygma exigua subsp. antipodea Warren. The
lectotype 8 [BMNH, here designated] is labeled: N. S. Wales [Australia], 1904.12.; Broken Hill; Noctuidae genitalia slide No. 595 8. The lectotype is designated to ensure nomenclatural stability in this confusing group of species and is illustrated in Fig. 176. The following syntypes become paralectotypes: (1) 8, Label data: Broken Hill; N. 3. Wales [Australia], 1904.12., 8. (2) 8, Broken Hill; N. S. Wales [Australia], 1904.12., 8 .
Material Examined. — Specimens were seen from the following countries: Aldabra Atoll, Bermuda, Canary Islands [Spain], Costa Rica, Dominica, Dominican Republic, Egypt, El Salvador, French Guiana, Germany, Guatemala, Honduras, India, Iran, Lebanon, Madagascar, Mexico, Pakistan, Panama, Papua New Guinea, Philippines, South Africa, Sri Lanka, Syria, Taiwan, Thailand, United States, Venezuela, Zimbabwe.
Distribution (Fig. 522). — S. exigua is the only cosmopolitan species in the genus. It has been found on all continents except Antarctica. It can migrate long distances and has been found in Sweden, Finland, and Latvia (Mikkola & Salmensuu 1965). Northern temperate regions are typically out of the breeding range of S. exigua. In the New World this species can reach southern Canada and is found throughout the United States. It occurs throughout Mexico and as far south as French Guiana and Venezuela (Todd & Poole 1980).