Copelatus nakamurai Guéorguiev, 1970

Source of material. The two instar II and five instar III larvae studied were reared ex ovo from adults collected at the following locality: Japan. Kasamatshu-cho, Mudoji, Gifu Prefecture, 4.V.2018. Y. Yoshimura, leg.

Diagnosis (instar III). The third instar of Copelatus nakamurai can easily be distinguished from that of the other species studied in this paper by the following combination of characters: HL = 0.80 mm; L3 <2.00 mm; U <0.40 mm; head capsule subquadrate, strongly constricted at level of occipital region (Fig. 28), scale-like sculpticels lacking over frontoclypeus, present over parietale; anterior margin of frontoclypeus narrowly convex, extending mesally well beyond adnasalia (Fig. 28); adnasalia margined with elongate acute teeth (Fig. 64); MP2/MP1> 1.50; GA/MP1> 1.50; 1.30 <LP2/LP1 <1.90; inner margin of stipes lacking a dorsal linear row of spinulae; profemur with less than 3 PV and 4 AV secondary setae; metafemur with less than 3 AV secondary setae; urogomphus composed of one urogomphomere; U/HW <0.40; U/LAS <0.50; Palaearctic.

Description, instar II

Body: Measurements and ratios aimed to characterize body shape are shown in Table 4.

Head: Head capsule subquadrate, strongly constricted at level of occiput; anterior margin of frontoclypeus narrowly convex, extending well beyond level of adnasalia; scale-like sculpticels lacking over frontoclypeus, welldeveloped over parietale; adnasalia margined with elongate acute teeth (see Fig. 64); HL = 0.61 mm; A/MP = 1.49; MP/LP = 2.06; MP2/MP1 = 1.60; GA/MP1 = 1.91; LP2/LP1 = 2.24; MNL/MNW = 3.11.

Thorax: L3 = 1.23 mm.

Abdomen: LAS = 0.45 mm; LAS subcylindrical, slightly constricted posteriorly at point of insertion of urogomphi. Urogomphus: U = 0.26 mm, composed of one urogomphomere; U/HW = 0.41; U/LAS = 0.58.

Chaetotaxy: Parietale with 8 temporal spines; position and number of secondary setae on legs are shown in Table 5.

Description, instar III (Figs 28–29, 64). As second-instar larva except as follows:

Body: Measurements and ratios aimed to characterize body shape are shown in Table 6.

Head (Figs 28, 64): HL = 0.81–0.84 mm; A/MP = 1.42–1.46; MP/LP = 2.02–2.25; MP2/MP1 = 1.51–1.74; GA/MP1 = 1.75–1.99; LP2/LP1 = 1.55–1.78; MNL/MNW = 2.85–2.98.

Thorax: L3 = 1.66–1.72 mm.

Abdomen (Fig 29): LAS = 0.66–0.69 mm; Urogomphus, U = 0.31–0.33 mm, composed of one urogomphomere; U/HW = 0.35–0.38; U/LAS = 0.45–0.49.

Chaetotaxy: Parietale with 9–10 temporal spines; position and number of secondary setae on legs are shown in Table 7.