Spodoptera pectinicornis Hampson 1895

Spodoptera pectinicornis (Hampson)
Figs. 167, 207-211, 313, 343, 375, 407, 439, 474-476, 526
Xanthoptera pectinicornis Hampson 1895: 300; 1896: 515. Caradrina hennia Swinhoe 1901: 495; Holloway 1989: Athetis hennia; Poole 1989: 133. Namangana pectinicornis; Hampson 1909: 545; Poole
1989: 677. Spodoptera pectinicornis; Holloway 1989: 135.
Diagnosis. — Sexually dimorphic, male with forewing darker than female. Male antenna bipectinate (Fig. 19). Forewing pattern obscure, smaller than both S. apertura and S. malagasy. Male genitalia with valve much narrower (Figs. 313, 343) than in either S. pecten (Figs. 311, 341) or S. cilium (Figs. 309, 339). Ampulla long and narrow with a pointed apex (Figs. 313, 343). Female genitalia with signum small and round (Figs. 407, 439).
Description. Adult Male. — Head: Basal segment of labial palpus dark brown mixed with cream scales; median segment dark brown mixed with cream scales; apical segment dark brown, apex cream. Frons with short scales brown; long scales brown; lateral spots at eye margin absent; vertex brown mixed with light brown. Antenna bipectinate; scape brown mixed with cream; flagellum cream annulated brown, becoming completely cream toward apex.
Thorax: Patagium light brown with a median brown transverse band. Tegula brown. Mesothorax light brown. Underside of thorax white. Prothoracic femur fuscous and cream; tibia with lateral scale tufts not extending beyond first tarsal segment, fuscous and cream subapical spot absent; tarsal segments fuscous with cream apical rings on segments 1 and 2. Mesothoracic femur cream and fuscous; tibia fuscous with cream median and apical bands, inner spur more than twice length of outer spur, spurs completely scaled; tarsal segments fuscous with cream apical rings. Meta thoracic femur more cream than fuscous; tibia more fuscous than cream; tarsal segments more fuscous than cream with cream apical rings.
Forewing: Length, 8-8.3 mm; ground color brown; basal line absent; longitudinal black dash at base 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 absent; 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 absent; orbicular spot indistinct, rufous; reniform spot indistinct, rufous; white scales along Cu vein and bases of M3 and CuAl veins absent; postmedial line a series of faint black spots; postmedian band undifferentiated; subterminal line absent; apex lacking a white patch; spots along outer margin absent; fringe brown. Underside ground color light brown; outer margin with black spots; reniform spot absent.
Hindwing: Ground color white suffused with light brown; costal area to vein Rs light brown, outer margin with light brown scales, vein Ml light brown; fringe white. Underside ground color white; costal cells C and Sc white speckled with gray scales; outer margin suffused with gray scales and with gray triangular spots in middle of cells Sc to CuAl; no spot on underside.
Abdomen: Eighth tergite with spiculate patches absent on caudal margin.
Genitalia: Uncus evenly curved; maintaining width throughout three-fourths length, narrowing to pointed apex; setae numerous. Scaphium elongate, well sclerotized. Tegumen lacking a pair of projecting arms on upper third. Costa slightly bent at middle (Figs. 313, 343). Costal process narrow, elongate; at base of costa on inner edge; perpendicular to costa of valve. Valve narrowly rounded. Anellifer with lightly sclerotized plate bearing setae absent. Ampulla elongate, slightly curved with a pointed, produced apex; curved toward sacculus; extends beyond apex of valve (Figs. 313, 343). Clasper proper absent. Clavus a minute round projection. Sacculus broadest at base, gradually tapering distally; apex pointed. Valvula narrower than valve; slightly differentiated from valve, apex not separate; apex pointed; indentation absent. Coremata reduced, closely appressed to sacculus; no distinct lobes. Juxta a narrow rectangular band with ventiolateral-lateral projections, median process as wide as base, ventral margin straight with curved sides. Anellus membranous. Vinculum U-shaped with a narrow base. Aedoeagus straight; coecum smaller in diameter than shaft; patch of spines absent on apex of membranous sheath surrounding aedoeagus.
Adult Female. — Essentially as described for male except:
Head: Basal segment of labial palpus cream; median segment cream; apical segment cream. Frons with short scales cream; long scales cream; vertex cream. Antenna scape cream; flagellum cream.
Thorax: Patagium cream. Tegula cream. Mesothorax cream. Prothoracic femur cream; tibia cream; tarsal segments cream. Mesothoracic femur cream; tibia cream; tarsal segments cream. Metathoracic femur cream; tibia cream; tarsal segments cream.
Forewing: Length, 8.3-9.3 mm. Ground color rufous; orbicular spot absent; reniform spot absent; postmedial line a broad brown band (can be faint); subterminal line reddish brown, indistinct; black triangular-shaped spots along outer margin. Underside ground color cream with light brown scales; outer margin with indistinct gray spots.
Hindwing: Ground color white; fringe white. Underside ground color white; costal cells C and Sc white speckled with light brown scales; outer margin spots absent.
Genitalia: Ventral plate of ostium bursa with height greater than width; distal margin straight; ventrolateral invaginated pocket of 8th sternite absent. Ductus bursae moderately elongate (length 2-3 times width); completely sclerotized. Appendix bursae membranous. Corpus bursae elongate, length greater than twice width; a few striae. Signum in apical half of corpus bursae; short, length less than 0.65 mm; almost vertical.
Larva. — See description, p. 104.
Type material. — Xanthoptera pectinicornis Hampson. The lectotype 8 [BMNH] is labeled: Ceylon; 95-37; Hambantota: March. Type locality: Hambantota, Sri Lanka. In Hampson's original description of pectinicornis (1895: 300) there were 2 8 specimens, one from Calcutta, and the other from Hambantota, Ceylon. Hampson (1909: 545) listed "18 type" from Hambantota in his list of specimens from Ceylon. This can be inferred as a lectotype designation and this specimen is the one mentioned above and is illustrated in Fig. 207.
Caradrina hennia Swinhoe. The lectotype 8 [BMNH, here designated] is labeled: [Borneo] Sarawak. The lectotype is designated to ensure nomenclatural stability in this confusing group of species and is illustrated in Fig. 211. The following syntypes become paralectotypes: (1) 9, Label data: Sarawak; 5377; (2) 8 , Label data: Sarawak; (3) 9, Label data: 1901-178 Sarawak; Borneo; Noc-
tuidae 9; Brit. Mus. Slide; No. 9980 9; (5) 9, Label data: Sarawak; 1901: 178 9.
Material Examined. — Specimens were examined from the following countries: Bangladesh, Indonesia, Papua New Guinea, Singapore, Sri Lanka.
Distribution (Fig. 526). — This species is widely distributed in southern Asia and the Indo-Pacific Region including India, Sri Lanka, Bangladesh, Indonesia, and Papua New Guinea.

Spodoptera pectinicornis (Hampson)
Figs. 167, 474-476 Diagnosis. — This is the most distinctive of all Spodoptera larvae. Its spiracles are stalked (Fig. 167) and the crochets are biordinal. There are no dorsal abdominal markings typically found in most other species.
Description of preserved specimens. — Head: Color brown; reticulate; frons yellowish brown; cutting edge of mandible serrate; P2 setae farther apart than PI setae; ratio ecdysial line: frons height, averages between 0.63-0.84. Thorax: Pronotum with dorsolateral stripe in form of a large spot; middorsal stripe narrow. Mesothorax segmental spot absent; with lateral dark spot absent. Metathorax with segmental spot absent; lateral dark spot absent. Abdomen: Body smooth; setal pinacula minute. Middorsal stripe absent. Segmental spots on abdomen absent. Segment 1 with lateral dark spot absent. Segments 2-6 with lateral dark spots in spiracular band absent. Spiracular band solid; spiracular band on segments 1-6 with white or light colored spot caudal to spiracle absent. Spiracles with black border and pale center; stalked. Subspiracular stripe continuous through abdominal segment 1. Crochets biordinal; total number on one side of body greater than 107 (total number: 133; n=l)
Host plants. — This species is monophagous and feeds only on waterlettuce, Pistia stratiotes (L.) (Araceae). It was released in 1990 in Florida as a biological control agent but has so far not become established (Habeck & Thompson 1994).

Spodoptera pectinicornis (waterlettuce moth) is a moth of the family Noctuidae native to Asia, where it can be found from the northeastern parts of the Himalaya to Sundaland and in New Guinea. It has been introduced as a biocontrol agent of waterlettuce in Florida in 1990, but the attempt was unsuccessful.

Caterpillar

The larvae feed on Pistia stratiotes and Eichhornia crassipes.