Copelatus oblitus Sharp 1882

Copelatus oblitus Sharp, 1882 Source of material. The five instar II and five instar III larvae studied were reared ex ovo from adults collected at the following locality: Japan. Mantaburu, Yonaguni-cho, Yonaguni-jima Island, Okinawa Prefecture. 24°27’04.1”N 122°57’36.8”E, 13VI.2019; K. Watanabe leg. Diagnosis (instar III). The third instar of Copelatus oblitus 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 1.50; GA/MP1> 1.50; 1.30 Description, instar II Body: Measurements and ratios aimed to characterize body shape are shown in Table 4. Head: Head capsule ovate, not constricted at level of occiput; anterior margin of frontoclypeus narrowly convex, extending mesally below level of adnasalia; scale-like sculpticels present over frontoclypeus and parietale; adnasalia margined with short bluntly rounded teeth (see Fig. 64); HL = 0.55–0.58 mm; A/MP = 1.39–1.51; MP/LP = 1.70–1.82; MP2/MP1 = 1.67–1.95; GA/MP1 = 1.85–2.32; LP2/LP1 = 1.56–1.89; MNL/MNW = 2.41–2.61. Thorax: L3 = 1.10–1.13 mm. Abdomen: LAS = 0.37–0.39 mm; LAS subconical, not constricted posteriorly at point of insertion of urogomphi. Urogomphus: U = 0.17–0.19 mm, composed of two urogomphomeres; U/HW = 0.26–0.29; U/LAS = 0.45–0.51. Chaetotaxy: Parietale with 3–5 temporal spines; position and number of secondary setae on legs are shown in Table 5. Description, instar III (Figs 30–33, 64). As second-instar larva except as follows: Body: Measurements and ratios aimed to characterize body shape are shown in Table 6. Head (Figs 30, 64): HL = 0.74–0.80 mm; A/MP = 1.50–1.60; MP/LP = 1.65–1.82; MP2/MP1 = 1.44–1.67; GA/MP1 = 1.59–1.83; LP2/LP1 = 1.31–1.47; MNL/MNW = 2.40–2.60. Thorax (Figs 32–33): L3 = 1.57–1.64 mm. Abdomen (Fig 31): LAS = 0.54–0.60 mm; U = 0.20–0.25 mm, U/HW = 0.22–0.27; U/LAS = 0.37–0.47. Chaetotaxy: Parietale with 3–4 temporal spines; position and number of secondary setae on legs are shown in Figs 32–33 and Table 7.
Published as part of Alarie, Yves, Michat, Mariano C., Watanabe, Kohei, Shaverdo, Helena, Wang, Liang-Jong & Watts, Chris H. S., 2022, An outlook on larval morphology of Copelatinae diving beetles with phylogenetic considerations (Coleoptera: Adephaga, Dytiscidae), pp. 151-205 in Zootaxa 5175 (2) on pages 175-177, DOI: 10.11646/zootaxa.5175.2.1, http://zenodo.org/record/7003344
{"references":["Sharp, D. (1882) On aquatic carnivorous Coleoptera or Dytiscidae. The Scientific Transactions of the Royal Dublin Society, Series 2, 2, 179 - 1003, pls. 7 - 18."]}