[Insect] Craniophora minuscula sp. n., a new species of the genus Craniophora Snellen, 1867 (Lepidoptera: Noctuidae: Acronictinae) from Japan

Abstract. In the present study, a new species of Craniophora Snellen, 1867, C. minuscula sp. n., is described as new to science from Japan, during course of the investigations on the Craniophora pontica-group. The external and genitalia morphology of both sexes is provided including the discrimination of the new species from the closely allied congeners. 

Keywords: Craniophora pontica-group, Taxonomy, New species, Genitalia morphology

Diagnonis

Craniophora minuscula externally resembles C. pacifica (Figs. 3, 10), C. taipaishana (Figs. 4, 11), C. draudti (Figs. 5, 12), C. simillima (Figs. 6, 13) and C. pontica (Figs. 7, 14). Due to the high similarity, reliable separation of the six taxa could require the study of genitalia, although C. minuscula exhibits some unique external characters: smaller size (wingspan of 24–32 mm compared to 28–32 mm in C. pacifica, 30–33 mm in C. taipaishana, 30–32 mm in C. draudti, 30–32 mm in C. simillima and 27–33 mm in C. pontica), brownish-greyish ground colour of forewing with slightly stronger rosy-tint brilliance, the narrower, smaller hook-like white dash on Cu2 vein, the crenulated postmedial line on M1, M3 and Cu1 veins, the somewhat elongated hindwing. Its relatives have more brownish ground colour of forewing however C. pacifica could have greyish ground colour.

Craniophora pacifica differs from C. minuscula by its larger size; the somewhat broader, angled forewing; the weaker basal dash; the evenly darker, double antemedial line; the slightly contrasty, double medial line at costal margin; the less crenulated postmedial line; the more or less evenly darker medial field; the more irregular orbicular macule; the somewhat indistinct claviform spot; the rather comma-like white dash; the rounded whitish hindwing with evenly broader brownish or blackish terminal band ended over the tornal patch and paler postdiscal line; in females, the somewhat darker brown hindwing with slightly more visible postdiscal line.

Craniophora taipaishana can be distinguished from the new species by its larger size; broader, angled forewing with brown ground colour; the somewhat weaker basal dash; the slightly contrasting, double antemedial line; the less crenulated postmedial line; the evenly darker medial field; the more or less rounded orbicular macule; the indistinct claviform and reniform spot; the longer and rather comma-like white dash; the rounded, almost pure white hindwing suffused with few brownish scales in the terminal area near to the veins and with a hardly visible or absent postdiscal line; in females, the somewhat evenly lighter brown hindwing.

Craniophora draudti differs from C. minuscula by its somewhat broader, angled and more uniform, brownish forewing; the somewhat weaker basal dash; the more regular antemedial line; the somewhat contrasty postmedial line; the more conspicuous white patch in the medial field at the ventral margin; more irregular orbicular macule; the less visible claviform spot; the slightly smaller, rather comma-like white dash; the slightly angled brown hindwing with weakly visible postdiscal line; in females, the somewhat triangular hindwing.

Craniophora simillima has more brownish forewing with slightly contrasty patterns; somewhat zigzagged, contrasty medial line; less crenulated postmedial line; more indistinct claviform and reniform spot; smaller, less hook-like white dash; slightly rounded whitish hindwing with fine brownish tint in terminal band; paler postdiscal line; faint discal spot; in females, lighter brown hindwing slightly darker the terminal band.

Craniophora pontica differs from all the other congeners by its more colourful forewing; the slightly more visible reniform spot filled with ochre scales; the hardly visible or absent small white dash; the more crenulated postmedial line; the diffuse terminal band and medial line of the whitish hindwing; in females, the whitish hindwing with diffuse brown scales in the terminal band.

Male genitalia (Figs. 15, 16). The close relationship with C. pacifica (Figs. 23, 24), C. taipaishana (Figs. 25, 26), C. draudti (Figs. 17, 18) and with a lesser degree to C. simillima (Figs. 21, 22) and C. pontica (Figs. 19, 20) is evident, however, the differences are very conspicuous. The clasping apparatus of C. minuscula (Fig. 15) differs from those of C. pacifica (Fig. 24) and C. taipaishana (Fig. 26) by its smaller size and the more rounded shape of the valvae. It can be distinguished from those of C. draudti (Fig. 17) and C. simillima (Fig. 21) by its more slender uncus and somewhat rounded shape of the valvae. Craniophora pontica (Fig. 19) has shorter uncus, slightly narrower and elongated valvae than its congeners. The valvae in the pontica species-group show some variation in more rounded vs. elongate shape but this variation may be constant within the given species. Craniophora minuscula (Fig. 16) has shorter vesica than C. pacifica (Fig. 23), C. taipaishana (Fig. 25) and C. draudti (Fig. 18). The proximal curve of vesica is turned upwards from right to left and in the latter three species forming a full loop in dorsal position. On the surface of the proximal curve, C. draudti and C. taipaishana have one patch of numerous small, spine-like cornuti, C. minuscula and C. pacifica have two patches of them. Craniophora minuscula differs from C. simillima (Fig. 22) by its larger aedeagus, much longer, curved vesica, with two separated patches on its surface covered by numerous small, spine-like cornuti. Craniophora pontica (Fig. 20) can be distinguished from all the other relatives by its somewhat complicated structure of the vesica. The full loop is in ventral position and its surface is covered by numerous small, spine-like cornuti. 

Female genitalia (Fig. 27). Craniophora minuscula can be distinguished from C. pacifica (Fig. 28) and C. taipaishana (Fig. 29) by its shorter ductus bursae; simpler appendix-corpus bursae complex with one half curve at its distal part. The new species differs from C. pontica (Fig. 32) by its shorter ductus bursae without additional arch at the junction to corpus bursae; broader and shorter appendix-corpus bursae; from C. draudti (Fig. 30) and C. simillima (Fig. 31) by the orientation of ductus bursae-corpus bursae junction; simpler structure of appendixcorpus bursae complex and expressed half curve at its distal part.

The male eighth abdominal segments (Fig. 33) show the close relationship of the above mentioned species. The bell-shaped tergite is widening by sections in C. minuscula, C. pacifica (Fig. 34), C. taipaishana (Fig. 35) and C. simillima (Fig. 37), but gradually in C. draudti (Fig. 36) and C. pontica (Fig. 38). Its distal end is much broader in C. taipaishana and C. simillima. Craniophora minuscula has more oval “window” in the tergite than in C. pacifica, more regular than in C. taipaishana, C. draudti and C. pontica and longer than in C. simillima. The proximal section of the sternite is usually arcuate with exception of C. pacifica. The two lateral sections of the sternite are widening gradually in C. minuscula but they are more parallel in all other species.

Description

Male (Figs. 1, 2). Wingspan 24–28 mm (forewing 12–13 mm). Head, thorax and forewing greyish with blackish, brownish scales, the latter with rosy-tint brilliance. Abdomen light brownish with three blackish hair brushes dorsally. Forewing narrow and short with obtuse apex; costa finely curved. Wing pattern clearly visible, basal line indistinct; antemedial line double, the outer line more contrasty and abrupt irregularly; medial line contrasty; postmedial line double, contrasty, crenulated at the M1, M3 and Cu1 veins; subterminal line indistinct; terminal line traceable by black dots. Medial field lighter and filled with ground colour. Orbicular macule small or medium sized, light brownish with white and black outlines; reniform spot relative large, indistinctly outlined, inner part darker; claviform spot reduced, faint; on Cu2 vein with narrow, hook-like white dash. Hindwing whitish, elongated, terminal band brownish; postdiscal line diffuse, faint; discal spot pale. Female (Figs. 8, 9). Wingspan 28–32 mm (forewing 13–15 mm). As male but somewhat larger in size, with brownish hindwing.

Male genitalia (Figs. 15, 16). Clasping apparatus weakly sclerotized; uncus strong, long, with hairy and pointed tip; scaphium developed, moderately sclerotized, juxta subdeltoidal with wider basal plate and long triangular dorsal extension. Valvae symmetrical, weakly sclerotized, rounded; sacculus expressed with tuft of dense hairs; harpe reduced, substituted by oblique medial sclerit; ventral margin of the valvae weakly sclerotized. Aedeagus cylindrical. Vesica tubular, everted forward, recurved ventrally upwards from right to left and continued in a full loop turned upwards at right side from right to left; proximal curve covered with spinulose structures; distal third of vesica covered by small spinules.

Female genitalia (Fig. 27). Ovipositor rounded shaped, as long as wide, tapering; papillae anales weakly sclerotized, oval, densely hairy; apophyses anterioris longer or equal long as apophyses posterioris. Ostium bursae moderately wide, dorsal plate weakly sclerotized, platelike. Antrum short, hardly sclerotized. Ductus bursae medium long, tubular, dorso-lateral curved; sclerotized crests running evenly to apical part of corpus bursae. Corpus bursae reduced, fused with the large appendix

bursae. Appendix-corpus bursae complex rather simple, tubular, recurved, distally with a loop.

Male eighth abdominal segments (Fig. 33) with sclerotized structures; tergite “bell-like”, with two symmetrical bars; distal half more sclerotized; middle section without sclerotization, strongly oval; sternite moderately sclerotized with two curved bars, connected by a rather straight cross-bar proximally; distal part triangular, broadened; middle section without sclerotization, moderately oval and rounded.

Reference: Ádám Kiss and Utsugi Jinbo. 2016. Craniophora minuscula sp. n., a new species of the genus Craniophora Snellen, 1867 (Lepidoptera: Noctuidae: Acronictinae) from Japan. Journal of Asia-Pacific Entomology 19 (2016) 929–935.  http://dx.doi.org/10.1016/j.aspen.2016.07.018