Research Article |
Corresponding author: Evgeny S. Koshkin ( ekos@inbox.ru ) Academic editor: Théo Léger
© 2021 Evgeny S. Koshkin.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Koshkin ES (2021) Life history of the rare boreal tiger moth Arctia menetriesii (Eversmann, 1846) (Lepidoptera, Erebidae, Arctiinae) in the Russian Far East. Nota Lepidopterologica 44: 141-151. https://doi.org/10.3897/nl.44.62801
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A thorough description and detailed photographs of all developmental stages of one of the rarest Palaearctic moths, Menetries’ tiger moth Arctia menetriesii (Eversmann, 1846) (Lepidoptera, Erebidae, Arctiinae), are presented. Eggs were obtained from a female collected in the Bureinsky Nature Reserve, Khabarovsk Krai, Russia. Data relating to specimens from this region significantly supplements previously published data, which was derived exclusively from more westerly parts of the species’ range. Larvae were reared mainly on dandelion (Taraxacum campylodes G.E.Haglund) in laboratory conditions. Some larvae were fed on Aconitum consanguineum Vorosch. leaves and larch (Larix gmelinii (Rupr.) Kuzen.) needles during certain periods of their lives. It is hypothesized that toxic compounds found in these plants resulted in high mortality rates among larvae prior to pupation. Metamorphosis anomalies in the form of larva-pupa intermediates and various morphological defects of pupae are documented for A. menetriesii for the first time. The assumptions of some researchers about the important role of Larix and Aconitum in larval development are questioned.
Menetries’ tiger moth Arctia menetriesii (Eversmann, 1846) is one of the rarest and most poorly studied Palaearctic moth species. Although the adults are large with bright colouration and the species is widespread throughout boreal Eurasia (from Finland in the west to Sakhalin Island in the east), it is primarily known from sporadic, disjunctive occurrences. The species is reliably recorded from Finland, Northern European Russia (Republic of Karelia and Arkhangelsk Oblast), the Urals (Sverdlovsk Oblast), Siberia (Yamalo-Nenets Autonomous Okrug, Khanty-Mansi Autonomous Okrug, Kemerovo Oblast, Altai Republic, Republic of Khakassia, Krasnoyarsk Krai, Irkutsk Oblast, Republic of Buryatia, Zabaykalsky Krai, and Republic of Sakha – Yakutia), Russian Far East (Amur Oblast, Khabarovsk Krai, Primorsky Krai, and Sakhalin Island), Kazakhstan, and North China (?Sungari River) (
The holotype of A. menetriesii originated from northeastern Kazakhstan (“Songoria”) (
For a long time, A. menetriesii was included in the monotypic genus Borearctia Dubatolov, 1984. Recently, Borearctia and 18 other arctiine genera have been synonymized with the genus Arctia Schrank, 1802 on the basis of molecular genetic data (
A. menetriesii is included in the Red Lists of both countries it currently inhabits. These are Finland, where it is classified as Data Deficient (DD) (
In July 2018, one A. menetriesii female was collected by the author in the Bureinsky Nature Reserve in the upper reaches of the Pravaya Bureya River (Khabarovsk Krai, Russia) (Fig.
Little is known about the biology of the immature stages of A. menetriesii.
The first reliable data of a natural host plant of A. menetriesii was obtained in the Baikal Region, where one last instar larva was found feeding on the extremely poisonous plant Aconitum rubicundum Fischer (Ranunculaceae) (
Considering the extreme rarity of A. menetriesii and the paucity of data on its biology, this study (1) describes and illustrates all developmental stages of the species; (2) presents the first observations on metamorphosis anomalies of this rare moth; and (3) discusses general patterns of its bionomics in a broader ecological context.
A female of A. menetriesii was collected flying low above the ground in sunny weather after a short shower of rain at 2.30 p.m. on July 1, 2018. Locality: Russia, Khabarovsk Krai, Verkhnebureinsky District, Bureinsky Nature Reserve, Dusse-Alin’ Mountains, upper reaches of the Pravaya Bureya River, Novyi Medvezhii cordon, 52°07'56"N, 134°17'30"E, 877 m. The habitat consisted of mountain larch forest composed of Larix gmelinii (Rupr.) Kuzen. with open-grown young Picea ajanensis Fisch. ex Carr. and Betula platyphylla Sukaczev trees. The lower layers were dominated by green moss species, Vaccinium vitis-idaea L., Rubus arcticus L., and Ledum palustre L. Individual bushes of Salix sp., Betula divaricata Ledeb., Rosa acicularis Lindl., Spiraea beauverdiana C.K. Schneid., and S. salicifolia L. were also present.
The captive female laid 105 eggs on July 3, 2018. First to third instar larvae were kept in ventilated plastic cages in groups of 5–10. Fourth to seventh instar larvae were confined to cages individually or in groups of two per cage. The food was changed twice a day. The cages were cleaned of food waste and frass, and treated with an antiseptic (Miramistin 0.01%) every day to prevent the development of infections. The larvae were maintained in laboratory conditions in the city of Khabarovsk indoors at an average temperature of ca. +25 °C under continuous illumination using three LEDs and daylight compact fluorescent lamps with 21–26 W power consumption. It has previously been established that several boreal arctiine species such as Arctia ornata Staudinger, 1896 and Grammia quenseli (Paykull, 1793), co-occuring with A. menetriesii can complete larval development to adults within two months under continuous illumination, thereby avoiding obligatory winter diapause of larvae that occurs under natural conditions (
Most first and second instar larvae of A. menetriesii were fed on Aconitum consanguineum Vorosch. leaves, while the rest were reared on dandelion (Taraxacum campylodes G.E.Haglund) leaves. All larvae were switched to the dandelion diet at the third instar. Approximately twenty larvae of the sixth and seventh instars were switched from dandelion to larch (Larix gmelinii) needles in order to test the hypothesis that Larix is an important host plant for A. menetriesii (
Photographs were taken using a Sony SLT-A65 digital camera with a Sony 2.8/50 macro lens. Voucher material is deposited in the author’s private collection.
Egg. The eggs are dome-shaped with a flat base and of light green colour (Fig.
Arctia menetriesii. A. Eggs; B–O. Larvae: B, C. First instar larva; D, E. Second instar larva; F, G. Third instar larva; H, I. Fourth instar larva; J, K. Fifth instar larva; L, M. Sixth instar larva; N, O. Seventh instar larva; B, D, F, H, J, L, N. Lateral view; C, E, G, I, K, M, O. Dorsal view.
First instar larva. All thoracic segments, as well as the posterior part of the seventh to tenth abdominal segments, are light orange (Fig.
Second instar larva. The general colouration of the head and body is similar to that of the first instar (Fig.
Third instar larva. Similar to the second instar in general (Fig.
Fourth instar larva. Very similar to the third instar, differing from it in more pronounced dark lines on the dorsum (Fig.
Fifth instar larva. Resembles third and fourth instars larvae, while differing from them in pale warts on the dorsal side of the second to sixth abdominal segments and two well-marked longitudinal dark lines (Fig.
Sixth instar larva. The colouration differs significantly from the larvae of the earlier instars (Fig.
Seventh instar larva. The larva differs significantly in appearance from the earlier instars and has an overall stockier build (Fig.
Pupa. Total length is 21.5–24.0 mm (average length 22.9 mm); maximum width is 7.5–9.0 mm. Pupa is almost entirely black or brown, slightly shiny (Fig.
Arctia menetriesii. A–C. Pupa with insignificant anomalies; D–F. Pupa with severe anomalies; G. Pupa in silken cocoon; H, I. Cremaster; J–L. Female emerged from larva-pupa intermediate (J, K. Head and thorax left covered with the larval cuticle; L. Larval cuticle removed); M, N. Lethal larva-pupa intermediates; A, D, H. Ventral view; B, E, G, K, N. Lateral view; C, F, I, J, L, M. Dorsal view.
Adult. The forewing length is 31 mm for a wild female, 25–29 mm for reared males, and 28–31 mm for reared females. The ground colour of the wings is either yellow or yellow-orange. The forewing and hind wing of a wild female are bright orange-yellow and identical in colour (Fig.
Developmental features. Low to moderate mortality was observed among larvae of the first to sixth instars. However, approximately 75% of larvae that reached the last instar died immediately before pupation.
A significant number of metamorphosis anomalies occurred during pupation. Some of them manifested as larva-pupa intermediates due to disrupted moulting (Fig.
Fourteen larvae reached the pupal stage. One of the most malformed pupae died. Although the remaining 13 survived to adult eclosion, only four adults (two females and two males) fully or almost fully spread their wings (Fig.
The adults hatched on September 12–23, 2018. The development cycle of A. menetriesii from oviposition to adult emergence took 72–83 days under laboratory conditions.
The description of the immature stages of A. menetriesii provided here supports in general and significantly expands on the information available for this species from Europe and Transbaikalia (
The unusually low ratio of resulting adults compared to the initial number of eggs is similar to the results obtained by other researchers (
It is worth noting that no metamorphosis anomalies of the immature stages were observed when rearing two other arctiine species (Arctia ornata and Grammia quenselii) coexisting with A. menetriesii on a dandelion diet under the same laboratory conditions.
Menetries’ tiger moth is extremely rare since the adults are difficult to detect, as they are not attracted to light, are either diurnal or crepuscular, and fly reluctantly. It is possible that larvae are also subject to high mortality in nature due to the metamorphosis anomalies observed in this study. Additionally, high mortality due to parasitoids may also be the case, as has been found in other arctiine species from the same region. For instance, Arctia ornata occurs sympatrically with A. menetriesii in the study area. All 23 sixth-instar larvae of this species collected there in July 2017 were parasitized by the larvae of a tachinid fly (Diptera, Tachinidae). It has been shown that parasitoid infestation significantly reduces imago abundance in several other arctiine species from Siberia (
Further studies on the ecology of A. menetriesii are required in order to determine what biotic and abiotic factors determine the low abundance of the species in nature and to develop a management plan for its conservation.
I am sincerely grateful to Dr. Christian Schmidt (Ottawa, Canada) for carefully reviewing the manuscript and providing valuable comments and ideas. The author is also grateful to Dr. Ivan N. Bolotov (Arkhangelsk, Russia) and Dr. Nikolay A. Ryabinin (Khabarovsk, Russia) for careful reading and valuable comments on the manuscript. Special thanks go to Dr. Anatoly A. Nechaev (Khabarovsk, Russia) and Evgeny V. Novomodny (Khabarovsk, Russia) for their help in identification of Aconitum consanguineum.