Platycerota incertaria (Leech)

Beljaev, Еvgeniy A. & Titova, Olga L., 2023, New data on geometroid moths (Lepidoptera: Geometroidea: Uraniidae and Geometridae) from Sakhalin and Moneron islands with notes on their taxonomy distribution and ecology, Zootaxa 5369 (1), pp. 1-41 : 8-9

Platycerota incertaria (Leech)

( Fig. 7 )

Synegia omissa , nec (Warren): Matsumura 1925: 175 (Ichinosawa).

Crypsicometa incertaria : Sato 2001b: 142; Kurina 2022a: GBIF occurrences 3023175784 (Gornozabodsk), 3023177809 (Tymovskoe).

Material examined. 1 ♂, Pionery, 18.VII.2015; S Kholmsk, 1 ♀, 10.VII. 2022; 12 ♂, 4 ♀, Sokhonda mount., 20, 23, 26.VII.2019.

Distribution. Russia (S RFE: S and central Sakhalin, S Kurils—Iturup and Kunashir), Japan (Hokkaido, Honshu, Shikoku, Kyushu, Tsushima),?SW China.

Remarks. The host plants of P. incertaria in Japan are various species of Ilex ( Aquifoliaceae ). In Sakhalin the moths fly from mid-July to mid-August. The observed moths were strictly associated with the Ilex rugosa thickets in the fern spruce-fir forest. They are almost not attracted to a lamp light, and were caught mainly at the day-time with a net, scaring them out of the thicket of I. rugosa .

It is a rare species in collections from Sakhalin. For the island it was previously reported by Matsumura (1925, as “ Synegia omissa ”) from Ischinosawa (Pervaya Pad’ village ~ 5 km N of Korsakov center), and two specimens are recorded in the GBIF website labelled as: “Saghalien, Naihoro [Gornozavodsk], 14.VIII.1934, [coll.] Cent. Exp. Sta.”, 46°33′ N, 141°51′ E (GBIF occurrences 3023175784); and “Tymovskiy rayon Tõmovsk [Tymovskoe], 12.VII.1975 ”, 50°51′ N, 142°39′ E (GBIF occurrences 3023177809); both in the IZBE Entomological Collection ( Kurina 2022a). The collection places of our specimens, as well as Pervaya Pad and Gornozavodsk, are located in the extreme south of Sakhalin, but Tymovskoye is localized in the central part of the island at about 51° north latitude, in a zone with dominating of boreal spruce-fir forests, approximately near the northern border of the distribution of Ilex rugosa (see Kiselyova 1988, fig. 50, A). Apparently, P. incertaria is widely distributed in Sakhalin, but is rarely observed due to the narrow location of its populations and to its strict association to the larval hostplant.

Interestingly, genus Platycerota Hampson includes several species distributed exclusively in the southern subtropics and tropics of East and South Asia. P. incertaria is the only exception, living in the subboreal and boreal forests in the Japanese Islands, Sakhalin, and the S Kurils strongly distant from the rest congeners. The reference of P. incertaria from “Western China, Moupin” (Baoxing in Sichuan) ( Leech 1897: 302; later Prout 1915: 315; Inoue 1977; Sato 2011; and others) is probably an erroneous identification of another similar species. Thus, P. incertaria is possibly endemic to Japan and neighbouring islands, and its adaptation to the harsh climatic conditions of central Sakhalin may indicate an autochthonous origin and a relict status of this species.

Figures

FIGURES 2–21. Epipleminae, Ennominae, Desmobathrinae and Geometrinae from Sakhalin. 2—Dysaethria illotata, ♀, S Kholmsk; 3—D. moza, ♀, Sokhonda mount.; 4—Eversmannia exornata, ♀, Yuzhno-Sakhalinsk; 5—Eilicrinia wehrlii, ♂, “Chertov most”, photo in nature by O.L. Titova; 6—Lomographa simplicior, ♂, Sokhonda mount.; 7—Platycerota incertaria, ♂, Pionery, photo in nature by O.L. Titova; 8—Aethalura ignobilis, ♀, S Kholmsk; 9—Gigantalcis flavolinearia, ♂, S Kholmsk; 10—Pachyerannis obliquaria ♂, central Kholmsk, photo in nature by O.L. Titova; 11—Cusiala stipitaria, ♂, S Kholmsk; 12—Larerannis orthogrammaria, ♂, S Kholmsk; 13—Lassaba nikkonis, ♀, S Kholmsk; 14— Zanclidia testacea, ♀, Sokhonda mount.; 15—Abraxas niphonibia, ♀, Moneron (a—upper side; b—underside); 16—Macaria continuaria, ♂, Nysh; 17–18—Alsophila japonensis, S Kholmsk: 17—♂, 18—♀, photo in nature by O.L. Titova; 18—Inurois asahinai, S Kholmsk; 20—Geometra dieckmanni, ♀, S Kholmsk; 21—Comibaena amoenaria, ♂, S Kholmsk. Scale—10 mm.