Vespa crabro flavofasciata Cameron, 1903

Vespa crabro flavofasciata Cameron, 1903 View in CoL

Description.

Head (Fig. 5 View Figure 5 ): CW / MW = 1.56–1.75 (n = 40, mean 1.66). Cranium with moderately strong, irregular rugo-reticulation, with the ventral area between the lateral margin of the clypeus and the outer margin of the cranium lacking this rugo-reticulation. Antenna positioned nearly at the level of the dorsal margin of the clypeus (Fig. 5 E, F View Figure 5 ) with a distinctly sclerotized rim (Fig. 5 E View Figure 5 ) and a diameter of 0.09 mm (Fig. 5 E, F View Figure 5 ). Temporal band (Fig. 5 I View Figure 5 ) with moderately defined lateral margins and a heavily margined dorsal edge, with moderate ferruginous pigmentation in the inner area, except for the ventral one-fifth region; ventral extremity positioned lower than the dorsal margin of the antenna (Fig. 5 F View Figure 5 ). Faint dotted patches on the frons, with a few setae located around the frontal suture and fewer than 15 setae on other areas of the frons. Paired suprafrontal marks well defined (Fig. 5 F View Figure 5 ). Clypeus width slightly exceeds the minimum distance between the antennae (Fig. 5 F View Figure 5 ). Main disc with a broadly and roundly convex dorsal margin, merging with the lateral margin without separation from the latter; pigmented spots present along the margins except at the labroclypeal suture, with (Fig. 5 C – E View Figure 5 ). Main disc relatively high, with a CLI of 1.5–3; main disc with approximately 80 setae; ventral section strongly transverse. Labrum (Fig. 5 G View Figure 5 , left) densely covered with small processes. Palate (Fig. 5 G View Figure 5 , right) with a large median patch; sclerotized patch dark, proximally wide, and narrowing distally, with conical papillae present in the proximal half; conical papillae also present in the ventral area of the palate; largest conical papillae 0.02 mm in diameter; spicules widely distributed in the medioventral region and dorsally along the lateral margin, and interspersed among the conical papillae (Fig. 5 B View Figure 5 ). Mandible (Fig. 5 A, E, H View Figure 5 ) with a heavily sclerotized apical third, with the entire surface containing numerous shallow pits (Fig. 5 A View Figure 5 ). Mandibular teeth I and II distinctly projected in comparison to tooth III. Tooth I similar in size to or slightly more produced than tooth II, while IIIa similar to or smaller than IIIb; teeth I and II separated at an angle of 50 ° – 70 °, II and IIIa at 45 ° – 80 °, and IIIa and IIIb at 80 ° – 105 ° (Type A) or 90 ° – 135 ° (Type B, similar to the condition in V. ducalis ); tooth I apically blunt and tooth II with a sharper apex (Type A); tooth II with a smooth dorsal margin and gibbous ventral margin; bifurcation point between teeth II and IIIa deeper than the other bifurcation points. Maxilla with 25‒30 setae. Prelabium with approximately 25 setae.

Body (thorax and abdomen): Body 19.5–25 mm in length (n = 40, mean 21.5 mm) and 9–11 mm in width (mean 10.0 mm); integument with gradually increasing setae from the fifth integument posteriorly and with even spicules. Spiracles deep, generally uniform in size, except for spiracles 1, 2, and 10, which are slightly smaller; largest spiracle 0.3 mm in diameter; spiracular rim 0.03 mm in thickness, lacking any processes; collar processes thick and short (occasionally not thick).

Remarks.

This species exhibits numerous dark spots along the dorsal and lateral margins of the clypeus. However, the number of spots varied among individuals. This variation may be due to certain environmental or genetic (Fig. 5 C – E View Figure 5 ). The dorsal and lateral margins of the clypeus form a broad, rounded convex shape, creating an almost semi-circular arc, a characteristic observed only in V. crabro flavofasciata (Fig. 5 C – E View Figure 5 ). In this species, mandibular tooth III presents in two forms (Fig. 5 H View Figure 5 ): Type A is observed in most individuals, and Type B, observed in a few individuals, resembles the form observed in V. ducalis . For Type B mandibles, the angle between tooth IIIa and IIIb ranges from 90 ° to 135 ° (Fig. 5 H View Figure 5 ). Additionally, spicules are distributed along the lateral margin of the palate, with a characteristic that contradicts the observations reported for V. crabro by Kojima (1998).

Specimens examined.

South Korea • 10 mature larvae; Daegu; 35°59'27"N, 128°35'49"E; 27 July 2021; Choi and Kim GoogleMaps • 10 mature larvae; Daegu; 35°53'31"N, 128°26'04"E; 28 July 2021; Choi and Kim GoogleMaps • 10 mature larvae; Jeollanam-do, Naju-si ; 35°01'46"N, 126°42'10"E; 18 Aug. 2021; Ma and Kim GoogleMaps • 15 mature larvae; Gyeongsangbuk-do, Yecheon-gun ; 36°40'16"N, 128°27'45"E; 2 Sept. 2022; Choi GoogleMaps • 10 mature larvae; Gyeongsangbuk-do, Sangju-si ; 36°21'58"N, 128°02'12"E; 5 July 2023; Choi and Ma GoogleMaps • 30 mature larvae; Gyeongsangbuk-do, Andong-si ; 36°35'12"N, 128°42'56"E; 18 Aug. 2023; Choi and Kim GoogleMaps • 8 mature larvae; Gyeongsangbuk-do, Daegu ; 35°54'59"N, 128°40'12"E; 20 Sept. 2023; Choi GoogleMaps • 10 mature larvae; Gangwon-do, Hongcheon-gun ; 37°47'19"N, 128°09'23"E; 22 Sept. 2023; Kim GoogleMaps • 5 mature larvae; Gyeongsangnam-do, Gimhae-si ; 35°21'36"N, 128°53'38"E; 10 Oct. 2023; Choi and Kim GoogleMaps • 10 mature larvae; Gyeongsangbuk-do, Yecheon-si ; 36°39'21"N, 128°24'10"E; 10 July 2024; Kim GoogleMaps • 5 mature larvae; Gyeongsangbuk-do, Andong-si ; 36°35'34"N, 128°46'35"E; 23 Oct. 2023; Choi and Kim GoogleMaps .