A study of the genus Protosticta Selys, 1855, with descriptions of four new species from Vietnam (Odonata: Platystictidae) Author Phan, Quoc Toan Author Kompier, Tom text Zootaxa 2016 4098 3 529 544 journal article 10.11646/zootaxa.4098.3.6 687e2f7e-8268-4707-9cd7-bf46f9753f3b 1175-5326 257723 A005DB6C-7389-4506-B2D5-392531F832EB 5. Protosticta ngoai spec. nov. ( Figure 4 A–H) Type specimens . Holotype : male, Thuong Hoa, Minh Hoa district, Quang Binh Province, central Vietnam , 30.V.2015 , Quoc Toan Phan leg. Etymology . The specific name ngoai is based to the Vietnamese term “ngoại” or “nh ngoại”, referring to the countryside of one’s wife. In this case, the type locality of this species is the countryside of the first author’s wife. Description of male holotype . Head ( Fig. 4 A) brownish black with a dark reddish mark on postfrons and occipital ridge. Labrum black with anterior border pale blue; mandibles and genae pale blue; a pale yellow marking between antefrons and eyes. Anteclypeus pale yellow, postclypeus wholly black. First and second segments of antennae pale yellow, remainder black. Posterior margin of head with indistinct pale yellow marking extending to level of posterior ocelli. Posterior border of occiput with black median narrow edge as in P. taipokauensis . Prothorax pale blue, dorsum with dark grey marking; lateral lobes dull black. Synthorax black with pale blue stripe over metepisternum; lower edge of metepimeron and venter pale yellow. Legs and coxae pale yellow with black stripe over flexor surface; spines brown. Wings ( Fig. 4 H) hyaline with a tiny pale brown smudge at tip. 17–18 postnodal veins in forewing, and 16 in hindwing. Pterostigma black. Abdomen long, S1–7 brown with yellow marking as follows: ventral side of S1–2 pale yellowish, S3 with a narrow basal stripe, extending to middle of segment; S4–7 each with a yellow mark at its anterior end; S8–10 completely black. Anal appendages ( Figs. 4 B–E) pale yellow with cerci strongly curved downward and with rounded tip; paraprocts flattened and twisted (spiraling) at base. Penile organ as Figs. 4 F–G. Measurements . Hindwing 25; abdomen including appendages 44. Female . Unknown. Differential diagnosis . In the genus Protosticta , four species have a large robust body that sets them aside from the other smaller species. These are: P. ngoai spec. nov. ; P. taipokauensis Asahina & Dudgeon, 1987 ; P. grandis Asahina, 1985 ; and P. robusta Fraser, 1933 . The latter species is known from the female only and can be separated from the other species by having 20–22 postnodal veins in both wings, as compared to 16–17 in P. ngoai spec. nov. and P. taipokauensis and 14–18 in P. grandis . P. ngoai spec. nov. is characterised by a black labrum ( Fig. 4 A), which separates it from all robust Protosticta species, which have pale yellow or blue labrums. The anal appendages of the male P. ngoai spec. nov. resemble those of P. taipokauensis in lateral view, but in ventrolateral view the cerci of P. taipokauensis show a strong basal indentation compared to the simple shape of the cerci of P. ngoai spec. nov. ; and whereas the apex of each cercus appears moderately bilobed in taipokauensis , it is rounded in P. ngoai spec. nov. ( Figs. 4 C–D, 4I –J).