Miltochrista fluctuata sp. n.

https://zoobank.org/ urn:lsid:zoobank.org:act: 01439A22-AD85-452E-A122-AE3562C8F475

(Figs 15–18, 31–33, 40)

Paratypes. THAILAND: 3 females, Nakhon Nayok, Khao Yai NP, Khao Khieo, 752m, 14°24'20''N, 101°22'14''E, 1. VI.2005, K. Černý leg. (CKC); 1 male, Chiang Mai Prov., Doi Inthanon Nat. Park, 44.5 km N of Chom Thong, 2240m, 26–27. V .1998, gen. prep. No.: MWM 31.743 (MWM/ ZSM); 1 male, Changwat Chiang Mai, Mt. Doi Inthanon, NP, 2300m, 7–8.IX.1999, A. Szabó & Z. Czere leg., gen. prep. No.: MWM 37.113 (MWM/ ZSM) ; 1 male, 1 female, Chiang Mai Prov., Doi Inthanon National Park, km 43.5 road (N of) Chom Thong – summit 5.5 km above checkpoint 2, 2050m, lower montane forest, 15–21.XI.1998, leg./ex coll. Dr. Ronald Brechlin, gen. prep. Nos.: MWM 33.539 (male), MWM 33.540 (female) (MWM/ ZSM) ; 10 males, 15 females, Chiang Mai, Fang, Doi Pha Hom Pok, 2110m, 20°06'16''N, 99°07'46''E, 23–24. V .2011, K. Černý leg., gen. prep. No.: AV2784 (female) (CKC); 2 males, 1 female, Chiang Mai, Fang, Doi Pha Hom Pok, 2050m, 20°07'30''N, 99°08'49''E, 5–6. V .2006, K. Černý leg., gen. prep. Nos.: AV2783, AV5472 (males) (CKC); 1 female, the same locality as previous, 27–31.X.2006, T. Ihle leg. (CKC); 1 female, Chiang Mai, Fang, Doi Pha Hom Pok, 1400m, 20°02'54''N, 99°09'49''E, 28–29.XI.2005, K. Černý leg. (CKC) ; 2 females, Chiang Mai, Fang, Doi Ang Khang, 1425m, 19°54'10''N, 99°2'28''E, 25–26. V.2011, K. Černý leg. (CKC).

Diagnosis. The forewing length is 9.0–11.0 mm in males and 13.0–13.5 mm in females. Miltochrista fluctuata sp. n. (Figs 15–18) is externally very similar to the sympatric M. megalytera sp. n. (Figs 1–4) and differs only in the more transversally directed discal spot of the forewing. In many cases, reliable identification requires the examination of the genitalia structures. In the male genitalia, M. fluctuata sp. n. is similar to M. etalina Volynkin, N. Singh, Černý, Kirti & Datta, 2022 (Fig. 14) recently described from Northeast India, from which the new species differs in the larger size and more distinct forewing markings. The male genital capsules of the two species display no remarkable differences and the main diagnostic features are found in the phallus and vesica structures. The phallus of M. fluctuata sp. n. (Figs 31–33) is dilated medially and distally whereas it is of uniform width in M. etalina (Fig. 34). In the vesica, the new species differs from M. etalina in the narrower main chamber, the presence of a ventral diverticulum bearing a dense cluster of short spinules, the presence of the long and broad subbasal diverticulum, the lack of the lateral cluster of spinules, and the markedly shorter distal diverticulum. Since the female of M. etalina is unknown, the female genitalia of the new species (Fig. 40) were compared with other similar species, i.e. M. setozia sp. n. (Fig. 41), M. megalytera sp. n. (Fig. 38) and M. idiomorfa (Fig. 39), from which M. fluctuata sp. n. differs clearly in the broad, heavily sclerotised and dorso-ventrally flattened ductus bursae, and the strongly elongate and curved, membranous appendix bursae whereas it is extremely short in the aforementioned congeners.

Distribution. The new species is known from Northern and Central Thailand (Chiang Mai, Nakhon Nayok and Nakhon Ratchasima Provinces).

Etymology. The specific epithet originates from the Latin ‘fluctuatus’ meaning ‘waved’ and refers to the wavy (sinuous) medial line on the forewing. The name is a noun in the nominative singular in apposition.