Spinosuncus, Chen, Kai, Zhang, Dandan & Li, Houhun, 2018

Chen, Kai, Zhang, Dandan & Li, Houhun, 2018, Systematics of the new genus Spinosuncus Chen, Zhang & Li with descriptions of four new species (Lepidoptera, Crambidae, Pyraustinae), ZooKeys 799, pp. 115-151 : 119-122

Spinosuncus gen. n.

Type species.

Paliga contractalis Warren, 1896

Diagnosis.

Species of Spinosuncus can be recognized externally by the yellow to fulvous wing ground colour, the fulvous to brown lines, the distinct subterminal lines usually arched to CuA2 then obviously angled or concave near the tornus. Diagnostic characters in the male genitalia are the short and stout, strongly sclerotized uncus distally with two spines or teeth, the lamellate, distally inflated sella set with fin-shaped setae forming editum, the dorsally inflated sacculus with the dorsal margin sclerotized and usually spinulose, the distally broad and usually spinulose phallus, and the spine-like cornuti appear funnel-shaped in the distal end of the vesica. The female genitalia are characterized by the strongly sclerotized lamella postvaginalis always extended dorsolaterally, and the sclerotized transverse band posteriorly in the cup-shaped antrum.

Spinosuncus moths are most similar in appearance to Pseudopagyda Slamka, 2013. Some species of Spinosuncus can be distinguished by the much smaller wingspan (usually less than 24 mm). However, some Spinosuncus species have a similar body size to Pseudopagyda , but they can still be differentiated by the wavy or dentate lines on the wings dorsally, especially the sinuate (rather than oblique, or slightly curved as in Pseudopagyda ) anterior part of the postmedial line near the costa. In the male genitalia, the sclerotized uncus, the fin-shaped setae (editum) of the sella, and the inflated sacculus distinguish Spinosuncus from Pseudopagyda . In the female genitalia, the long and slender ductus bursae is distinct from the extremely short ductus bursae of Pseudopagyda .

Description.

Head. Frons oblique, yellowish brown, with white lateral bands. Vertex with moderately raised scales projecting between antennae. Labial palpus obliquely upturned, exceeding frons by 2/3 length of head or slightly less, third palpomere porrect, yellowish brown with base contrastingly white. Maxillary palpus small, yellowish brown, tips pale yellow, sometimes mixed with white. Proboscis well developed, with basal scaling white. Antenna pale yellow, with cilia as long as width of corresponding flagellomeres in male. Thorax. With appressed scales, yellow. Legs unmodified. Foreleg brown, tibia white with brown cross band medially, tarsus white; midleg pale brown, tibia and tarsus white ventrally; hind leg pale yellow, tinged with white, basal inner spur longer than apical inner spurs. Forewing subtriangular, termen gently arched; retinaculum a tuft of curved bristles from below base of discal cell. Hindwing fan-shaped, costal margin translucent whitish; frenulum simple in male, with two acanthae in female. Wing venation (Figure 2) in forewing with cell about half length of wing; R1 free, from 4/5 of anterior margin of cell, R2 free but adjacent to stem of R3+R4 in about basal half, R3 and R4 stalked to about 2/3, R4 to just before apex, R5 parallel to stalked R3+R4 at base then diverging; M1 moderately close to R5 at base, M2 widely separate from M1, closing vein concavely curved; M2, M3 and CuA1 from posterior angle of cell, M3 closer to M2 at base than to CuA1, then diverging; CuA2 from 3/5 of posterior margin of cell; 1A faintly sinuate to tornus, 2A forming complete loop and distally recurved before joining 1A, sometimes disconnected. Hindwing with cell about 1/3 length of wing; Sc+R1 and Rs anastomosing for 1/3 beyond end of discal cell, Rs and M1 short-stalked, closing vein concave, angled medially; M3 closer to M2 at base than to CuA1, parallel with M2 at base, then diverging; 1A complete but weak, 3A curved. Abdomen. Slender, usually yellowish, sometimes dark brown, apical margin of segments usually tinged with white. Male genitalia. Uncus short and stout, nearly quadrate, with wide base; usually strongly sclerotized; distal end with two or four sharp spines laterally or distally bifid forming two teeth; glabrous or ventrolaterally set with few setae, or densely setose at base of teeth. Tegumen quadrate. Vinculum U-shaped. Saccus short, near triangular, rounded at apex. Valva tongue-shaped, varying in width, tapering towards apex, set with hair-like setae on inner side; transtilla sub-triangular, meeting in middle, usually with setae on dorsal margin; costa simple, costal sclerotized band narrow to broad, extended to beyond 2/3 of dorsal margin; sacculus broad, expanded except basal part, with dorsal margin strongly sclerotized and often spinose; sella slender to broad, lamellate, distally inflated, set with modified setae (editum), varying from fin-shaped to thick, needle-shaped. Juxta heart-shaped to nearly pentagonal. Phallus with distal part broad and moderately setose, usually spinulose; vesica in distal part with numerous spine-like cornuti appear funnel-shaped, sometimes with several large spicules. Female genitalia. Ovipositor lobes flat, densely setose. Sinus vaginalis well developed, membranous, usually with sclerotized, streak-like or hook-like notches anterolaterally (absent in S. praepandalis and S. curvisetaceus ); lamella postvaginalis band-shaped, sclerotized (weakly sclerotized in S. contractalis , S. rectacutus and S. brevacutus ), always extended dorsolaterally. Antrum membranous or sclerotized and granulated, cup-shaped, with sclerotized transverse band posteriorly. Ductus seminalis originating from anterior end of colliculum. Ductus bursae with base slightly rotated, as long as or longer than length or diameter of corpus bursae; colliculum ring-shaped, sclerotized. Corpus bursae drop-shaped or globular; accessory bursa present, sometimes with second signum at base; main signum rhomboid.

Biology.

All of the Chinese material has been collected during the night at light. Host information is currently unavailable. Spinosuncus aureolalis and S. contractalis occur sympatrically with species of Pseudopagyda in some places. According to Bänziger (1995), they are not lachryphagous.

Distribution.

Spinosuncus occurs in South China (Figure 28), India, and Thailand.

Etymology.

The generic name is a compound word that refers to the uncus distally with spines ( “spinosus” in Latin). The resultant name is masculine in gender.