3.1.1. Taxonomic accounts
Genus Sphecodoptera Hampson, [1893]
Sphecodoptera Hampson, [1893]: 189. Type species. Sphecia repanda Walker
Sphecia Hampson, 1919: 80.
Sesia Spatenka, Lastuvka, Gorbunov, Tosevski & Arita, 1993: 87
Spherodoptera Matsumura, 1931: 1017.
Scasiba Matsumura, 1931: 8.
Sphecodoptera sheni (Arita & Xu, 1994)
Sesia sheni Arita & Xu, 1994: 61. Type locality. Nanjing, Jiangsu, China
Scasiba caryavora Xu & Arita, 1994: 2.
Sphecodoptera sheni Kallies, Arita, Owada & Wang, 2014: 587.
Material examined. Korea. GW: 2♀, Wonju, Moosil-dong 1710, 8.VII.2020, J-K. Jung; 2♂, 1♀, ditto, 12.VII.2022, J-K Jung, gen. slide no. IPE04, IPE05/S.Kim; 5exs, Chuncheon, Woodoo-dong 1121, 12.V.2023, B. Lee. GG: 9 exs, Seongnam, Bungdang-gu, Sampyong-dong, 15.VII.2022, JK Jung; 5, Goyang, Ilsan, Juyeob-dong 152, 6.V.2023, B. Lee; 6, Bucheon, Yeokgok-dong, 3. VI. 2023, B. Lee. CB, 2, Chungju, Heungdeok-gu, 28. IV.2023, S. Kim. Daegu, 6, Jung-gu, Gukchaebosang-ro 139gil 1, 8-12.IV.2023. I. Park.
Diagnosis. This species is superficially close to
Scasiba rhynchioides in having yellowish scales on thorax, but it can be easily recognized by the 1
st tergite of abdomen black with a narrow and yellow posterior band and the 2
nd and 3
rd tergites dark brown with reddish brown centrally (
Figure 3E). The male genitalia of
S. sheni is also differentiated from
S. rhynchioides by a finger-like processus on the saccular margin antemedially (Figure 5E). Female genitalia are also distinguished from that by the long and narrow ovate corpus bursae bearing distinct signum (Figure 5G-H).
Host Plants. Carya illinoensis (Wang.) K. Koch (Juglandaceae);
Quercus suber Linnaeus,
Q. variabilis Blume,
Q. acutissima Carruthers and
Castanea mollissima Blume (Fagaceae) [
13,
14];
Quercus palustris Münchh. (this study).
Distribution. Korea (GG, GW, CB, Daegu) (this study), China (Jiangsu) [
14].
Remark. Of the pin oak street borers, the large-sized sesiids were identified as
S. sheni in this study. This species was found in Korea for the first time since it was reported form China. According to Arita et al. [
14], this species has been reported as a pest of North American native pecan trees planted as street trees in Nanjing, China. Based on investigation of number of pupal exuviae,
S. sheni was higher than other sessid borer density and their distribution on tree was aggregated between ground to 1m in heights.
Genus Paranthrenella Strand, 1916
Paranthrenella Strand, 1916: 47. Type Species. Paranthrenella formosicola Strand
Type Material. Holotype: One male, Korea, GW, Wonju, Moosil-dong 1710, 2.VII.2022, JK Jung, gen. slide no. IPE03/ S. Kim; Paratypes: two males, ditto, 8.VII.2020, JK Jung.
Diagnosis. This species is externally similar to
Paranthrenella formosicola in having a long and slender abdomen (
Figure 4E). However, it can be readily distinguished from the former due to the lesser development of yellow scales between the thorax and tegula (
Figure 4C), as well as the abdomen dorsally (
Figure 4E). Except for the 4th and 7th tergite, the presence of yellow scales on the posterior margin of each tergite is not noticeable. In contrast,
P. formosicola has thickly developed yellow markings on the posterior margin of the 2
nd, 4
th and 6
th tergites in male and almost entire tergites in female. The male genitalia is also differentiated from that by the asymmetrical valva including a ridge line and aedeagus bearing four small cornuti at apex.
Description. Male (
Figure 4). Wingspan. 22.0-28.0 mm; forewing length 10.0-12.5 mm; body length 17.0-19.5 mm. Head: frons pale brown; vertex dark brown; occipital fringe yellow; scape of antenna yellow entirely, shorter than 1/2 diameter of eye; flagellum blackish brown antemedial and apical parts, tinged with yellow postmedial part dorsally, short setose at apex, yellow ventrally; labial palpus entirely yellow; 3
rd segment of labial palpus 2/3 length of 2
nd segment. Thorax: patagium blackish brown, mixed with pale brown laterally; tegula blackish brown with yellow scales on posterior margin; mesothorax blackish brown with two spots of yellow scales on posterior margin; metathorax blackish brown. Forewing hyaline; costal margin blackish brown; dorsal margin yellowish brown; wing base blackish brown tinged with bright yellow; bright yellow between radius vein 2 (R2) and R3; cilia yellowish brown; forewing vernation: radius 4 (R4) stalked with R5 antermedially; anterior transparent area (ATA) extended to 3/4 of forewing; posterior transparent area (PTA) extended to 4/5 of forewing; apical 1/3 exterior transparent area tinged with yellowish brown scales. Abdomen blackish brown with yellow scales noticeably at posterior margin of tergite 4 (T4) and T7.
Male genitalia (
Figure 6). Tegumen-uncus complex broad; scopula androconialis well-developed, slightly shorter than the length of tegumen-uncus complex; crista gnathi lateralis large, a cup-shaped; crista gnathi medialis relatively narrow, oval. Valvae elongated, oval, asymmetrical; right valva with asymmetric ridge line from basal crista sacculi to apex, rather dense setose followed the ridge from base to 1/3 of valva; left valva without ridge. Saccus with bifurcate terminal margin, a reverse blunt fork-shaped, as long as vinculum. Aedeagus as long as valva, gradually narrow from base to apex; vesica curved at sub-apex; bearing four cornuti.
Female genitalia. Unknown.
Host Plants. Quercus palustris Münchh. (this study).
Distribution. Korea (GW) (this study).
Etymology. The species name is derived from a common name of the host plant (Quercus palustris), pinoak- plus a Latin diminutive suffix, -ula, referring to the insect pest borer of the pin-oak.
Remark. In the pin oak street insect pests, the small-sized borers were identified as new species, P. pinoakula sp. n., in this study. This species was only found from WonJu (GW) in Korea, and their densities were relatively lower compared to S. sheni.