PUBLISHED IN: Atalanta, Vol. 31, Iss. 1/2, p. 171-177, colour plate XIII. (Wurzburg)
A new subspecies of Polyommatus icadius (Groum Grzhimailo, 1890)
(Lycaenidae, Lepidoptera) from Russian Altai
V. V. Ivonin*, O. E. Kosterin**
Новый подвид Polyommatus icadius (Groum Grzhimailo, 1890)
(Lycaenidae, Lepidoptera) с Русского Алтая
В. В. Ивонин*, О. Э. Костерин**
* Vystavochnaya str. 32/1, app. 81, Novosibirsk 630078 Russia
** Institute of Cytology & Genetics SD RAS, Lavrentiev ave. 10, Novosibirsk 630090 Russia
Keywords: Lepidoptera, Lycaenidae, Polyomatus icarus species group, Polyommatus icadius (Groum Grzhimailo, 1890), new subspecies, Altai Mountains, Siberia, Russia
Ключевые слова: Lepidoptera, Lycaenidae, группа Polyomatus icarus, Polyommatus icadius (Groum Grzhimailo, 1890), новый подвид, Алтай, Сибирь, Россия.
Polyommatus icadius (Groum Grzhimailo, 1890) is found out in SE (Russian) Altai Mts. in the upper Dzhazator River valley. This population is described as Polyommatus icadius cicero Ivonin et Kosterin, ssp. n. Among others, the main characteristic feature of these butterflies is much better developed orange submarginal spots on wing underside than in Central Asian (including Dzhungarian) specimens, that to a great extent continues the trend of their increase in this species to the North-East. Finding of this strict monophagous species on wild chickpeas (Cicer) agrues against an introductive nature of Cicer songaricum Steph. ex DC. in Altai.
Polyommatus icadius (Groum Grzhimailo, 1890) найден на ЮВ (Русском) Алтае в верховьях р. Джазатор. Эта популяция описывается как Polyommatus icadius cicero Ivonin et Kosterin, ssp. n. Среди прочих, основным ее отличием от среднеазиатских (в том числе джунгарских) бабочек является гораздо более сильное развитие субмаргинальных оранжевых пятен на нижней стороне крыльев, что в значительной степени продолжает тенденцию их увеличения у этого вида к северо-востоку. Нахождение этого строгого монофага на видах дикого нута (Cicer) говорит не в пользу заносной природы Cicer songaricum Steph. ex DC. на Алтае.
Systematics of the genus Polyommatus s. str., especially of the species group Polyommatus icarus (Rottemburg, 1775), is quite complicated. However, the species Polyommatus icadius (Groum Grzhimailo, 1890) (the chickpea blue) has an advantage as being a subject of a special paper by A. B. Zhdanko (1993). Perhaps the most peculiar feature of this species is its strict oligophagy on species of the genus Cicer (chickpeas, Cicer songaricum Steph. ex DC. and C. flexuosum Lipsky so far being known as foodplants) and a corresponding confindness to phytocoenoses incorporating these plants. A. B. Zhdanko (1993) describes the range of P. icadius as follows: "Occurs in Tarbagatai, all the mountain chains of Dzhungaria (and, probably, in West China), in the North (so far not reported from Kunge Alatau) and West Tien Shan, in the mountains of Ghissaro-Alai, the Pamirs, and, probably, Hindikish". Thus, the species was not hitherto found on the territory of Russia. At the same time, one of its foodplants, the Dzhungarian chickpea (Cicer songaricum) is do known in Russia from the Kosh-Agach District of Altai Republic: the headwaters of the Karagem ("an Argut River tributary upstream of Kara-Ir"), "Uzun-Bom on the Argut River" (Krylov, 1933), from the valley of the Direntai (Argem) River on the eastern spurs of the Katunskii Mt. Range (Artemov, 1993) and from the Dzhazator River valley (Dyachenko, 1995; Kamelin, 1998).
In 1998, during stationary studies in the Dzhazator River upper flow, we were lucky to found out both the Dzhungarian chickpea growing in abundance and, as well, the blue species under discussion, in mass quantities. The chickpea and chickpea blues were found in two sites:
1. At 2000 m above sea level on the souhtern slope of a small hilly ridge dividing an ancient, now abandoned and occupied by an anonimous brook, valley of the Dzhazator and its recent valley next to the Akbul River mouth, 7 km upstream of the fall of the Zhumaly River (further in the text this locality will be called DRY MOUNTAINS). The Dzhungarian chickpea grows here by sparce plots of thickets on steep detrituous slopes. This remarkable plant forms more-or less sphaerical "bushes", it has rather large violet-blue flowers, much resembling the males of blues, the finely pubescent foliage and stems covered by a sticky secret of a strong scent of honey and a saltish taste. The chickpea grew in a plant community with rather small projective cover (about 60%) of the following composition: abundant (cop by Drude scale) Festuca kryloviana Reverd., Avenula hookeri (Scribner) Holub, Ziziphora clinopodioides Lam., sparse (sp) Junpierus pseudosabina Fisch. et Mey., Aconogonon alpinum (All.) Schur., Cicer songaricum, Hedysarum gmelinii Ledeb., Geranium pratense L., Galium verum L., Thymus serpillum L. s.l., Campanula rotundifolia L., Artemisia santolinifolia (Pamp.) Turcz. ex Krasch., Psatyrostachys juncea (Fisch.) Nevski., Poa aff. urssulensis Trin., solitary (sol) Silene sp., Pentaphylloides fruticosa (L.) O. Schwarz, Heracleum dissectum Ledeb., Seseli buchtormense (Fisch. ex Spreng.) Koch., Lagopsis marrubiastrum (Steph.) Ik.-Gal., Allium altaicum Pall. First specimens of P. icadius were recorded on 27th June, further were observed also from 11th to 20th June, then observations were ceased.
2. Detrituous bluffs of the right board of the Dzhazator River valley, 1800 - 1950 m above sea level, studied by us within 3 km upstream of the fall of the Chikty Rivulet (further called DZHAZATOR). There the chickpea is very abundant and occupy a considerable area, there is no doubt they continue further downstream of the Dzhazator. The vegetation on these bluffs is represented there by: abundant (cop) Carex pediformis C. A. Mey., Poa aff. urssulensis, Artemisia santolinifolia, sparse (sp) Aconogonon alpinum, Pentaphylloides fruticosa, Stipa zalesskii Wilensky, Geranium pratense, Cicer songaricum, Spiraea chamaedryfolia L., Ziziphora clinopodioides, solitary (sol) Allium lineare L. and others. This locality was studied on 20th and 21st July only, the chickpea blues being observed in great abundance. There were quite fresh specimens among them but the majority of individuals were worn out and were practically lacking the apical one third of their fore wings.
In both localities the habitat of the chickpea blue coincided in detail with those described by A. A. Zhdanko (1993): the butterflies keeped to the chickpea thickets on steep detrituous southern slopes, only rarely and to a small distance penetrating to the meadowy areas of floodland where could be observed together with Polyommatus icarus, from which they differed well by a considerably larger size, small and paler orange submarginal spots, a much wider basal suffusion of greenish-blue glittering scales on the hind wing underside, and often reduction of black dots in the cell on the fore wing underside. In a cloudy weather the butterflies of both sexes of P. icadius rested on the chickpea "bushes" or inside them, sometimes on other plants. In a sunny weather the males flew swiftly along the slope, permanently as if examining "bushes"of the chickpea but did not sit on them. Often the males were seen sitting on the wet ground, stones, or grass at the river bank or flying along the water in places where the river undermines the bluffs. Females mostly used to rest on detritus or low on foliage of the chickpea or other neighbouring plants (Fig. 1), rarely flying from one place to another, they were much less frequently seen at the water. We repeatedly observed feeding of imagines on the flowers of Ziziphora clinopodioides.
Polyommatus icadius was described, as a variety of P. icarus, from Ferghana, Alai, and the Kunzhut Mountains (Groum-Grzhimailo, 1890). A. A. Zhdanko (1993) wrote that the specimens from the Pamirs have the least developed (up to reduction) sumbarginal orange spots on the hind wing underside, while they are the best developed in populations from the northern part of the species range (Dzhungaria, the Zailiiskii Alatau Mts.). In a collection of the Siberian Zoological Museum at the Institute for Animal Systematics and Ecology of the Siberian Division of the Russian Academy of Sciences, Novosibirsk, there are specimens of P. icadius, collected, as well in the second half of the summer, in the West Pamirs (both sexes, Khorog, the botanical garden and environs, 2900 m above sea level, collected by A. Kuzyakin on 17th August 1976 and M. Danilevsky on 3rd June 1989) and in the Dzhungarian Alatau Mts. (only males, the Northern Chain, 5-18 km NE of the city Tekeli, the Kora River lower flow, 1400-1600 m above sea level, 11st August 1994, V. Dubatolov & O. Kosterin leg.; and the Southern Chain, The Tyshkantau Mts., 40 km NNE of the town Zharkent, the Tyshkan River, 2500 m, 24th July 1994, V. Dubatolov & O. Kosterin leg). These specimens quite support the mentioned trend. Our Altai specimens extend this trend further being its extreme expression. Their differences from the Dzhungarian ones to our mind are great enough to describe them as a new subspecies.
Polyommatus icadius cicero Ivonin et Kosterin, ssp. n.
Materials: The holotype - a male: DZHAZATOR [data on the labels: Russia, Siberia, Altai Mts., Kosh-Agach Distr., precipitous steppefied southern slopes of the Dzhazator River right bank 5 km upstream of the Zhumaly River mouth, about 1900 m alt.], 21.07; the allotype - the same locality and date; paratypes: DRY MOUNTAINS [data on the labels: Russia, Siberia, Altai Mts., Kosh-Agach Distr., steppes on southern slopes of a ridge on the Dzhazator River left bank next to the Akbul River mouth, about 2000 m alt.]: 27.06 - 1 m, 11.07 - 1 m, 12.07 - 4 m, 14.07 - 1 m, 17.07 - 3 m, 19.07 - 7 m 1 f, 20.07 - 8 m 4 f (V. Ivonin, O. Kosterin leg.); DZHAZATOR: 20.07 - 22 m 15 f (O. Kosterin leg.), 21.07 - 8 m 21 f (V. Ivonin leg.). The holptype, allotype, and part of paratypes are kept in the Siberian Zoological Museum, Novosibirsk, a part of type series is kept in a private collection by V. Ivonin, few paratypes are transferred to EMEM (Entomologische Museum, Marktleuthen, Eitschberger).
Male (Fig. 2 a, b). Fore wing length 17-19 mm (17 mm in the holotype), wing expanse 29-31 mm (29 mm in the holotype). Wing upperside ground colour do not differ from specimens from other regions being bright light-violet-blue with a narrow (about 0.3 mm) black border and white fringe; hind wing fore margin mainly blakish in front of vein Rs. Wing underside ground colour very light ash-grey. Basal suffusion of hind wing glittering greenish-blue, it occupies between 1/4 and 1/3 of wing area, as a rule it expands to an imaginary line going from the basal black spot in the space between Sc+R1 - Rs to the anal angle. On hind wing the submarginal orange spots are well developed and are of a saturated colour; as a rule the orange colour is distinctly seen even on the foremost spots in the spaces Sc+R1 - Rs and Rs - M1, but in some specimens may disappear from these spots. Dark submarginal spots are well seen also on fore wing underside, two of them, those in scapes M3 - Cu1 and Cu1 - Cu2, as a rule being accompanied with orange colour. On fore wing a black spot in the cell may be absent (in about one third of specimens), strongly reduced or normally developed. White-rimmed black discal spots are well expressed both on hind and fore wings. There are from four to six (five in the holotype) postdiscal black spots on fore wing, they are bright and distinct, with inconspicuous white rims. A white brand between medial and postdiscal rows of black spots is not seen. Genitalia: of a structure typical for the Polyommatus icarus species group.
Female. Fore wing length 17-18 mm (17 mm in the allotype), wing expance 28-31 mm (28 mm in the allotype). In 12 of 42 females collected, wing upperside is evenly dark-brown (Fig. 2 e, f), sometime with some admixture of blue scales in basal area. On both wings darker submarginal spots are noticeable, accopmanied with bracket-shaped orange spots. On fore wing there are two or three hardly noticeable spots, or none, on hind wing there are four to six spots, three or six of which are well expressed. In 30 females (including the allotype) wing upperside is mainly deep violet-blue (Fig. 2 c, d), fore margin of both wing being blackish-brown up to vein R5 on fore wing and M1 on hind wing. On fore wing the violet-blue area is bordered with dark submarginal spots fused to each other and to wing margin, the orange spots on them being absent or hardly noticeable. Transversal vein on fore wing outlined with a black discal spot. On hind wing the blue-violet colour area extends to wing margin narrowly bordered with black and contains a row of round black submarginal spots accompanied proximally with black shevrones, spaces between the black spots and shevrones being occupied with orange spots, well expressed in lower part of wing and disappearing to fore margin; discal spot absent. Wing underside ground colour relatively dark, brownish-grey, basal suffusion on hind wing glittering-green and rather narrow as hardly reaching a row of 3-4 basal black spots. All submarginal orange spots are large, well developed on both wings; they hardly dercease in size to wing fore margins and often fused to each other. All black markings on fore wing are larger than on hind wing. On fore wing there are as a rule two basal spots (one residing in the cell), they are absent in about 1/4 of specimens. White brand between medial and submarginal rows of black spots well expressed. Genitalia: as in the nominotypical subspecies (Fig. 3) but in all the six specimens studied the basis of the anthevaginal plate is not so concave as it is depicted on Fig. 1 in Zhdanko (1993), noteworthy, this concavity is not seen in all the females from the Pamirs studied by us.
The butterflies of the new subspecies differ from the Dzhungarian ones, which we consider as belonging to the nominotypical subspecies (Fig. 2 g, h), first of all by much more expressed orange submarginal spots on the wing underside. In males they as a rule are of an intensive colour and are present up to the wing fore margin, in the lower part of the wing they are large, occupying a half of the interval between black spots of the submarginal and medial rows, and are almost fused to each other, their black rims being pointed shevrones. In the Dzhungarian specimens the orange spots are dull and small, they occupy less than a half of the interval between the black spots of the submarginal and medial rows and are separated from each other by spaces almost equal the spot widths, their black rims being rounded brackets. In the new subspecies ,on the hind wing underside the greenish-blue suffusion is more developed, the ground colour is as a rule somewhat darker as compared with the Dzhungarian butterflies. As different from the new subspecies, the Dzhungarian and Pamirian males have no or hardly noticeable discal spot. The males of the new subslecies have no white brand on the hind wing underside, which is noticeable, although very uncontrasted, in some Dzhungarian and the majority of Pamirian males. Unfortunately, we have in our disposal no females from the Dzhungarian or North Tien Shan for comparison, while differences between the Altaian and Pamirian females are drastic: the latters are much smaller, their wing underside ground colour is paler, the orange submarginal spots on the wing underside are much smaller and paler while on the upperside their are more developed as being large and well noticeable on the fore wing as well. Unfortunately, A. B. Zhdanko (1993) in his paper did not mentioned deep-blue females, but he communicated us personally that such females occur throughout the species range. As we see, in Altai they predominate.
The subspecies is named after the most splendid figure of the ancient Roman culture, whose generic name had been derived from the word "cicer" meaning "pea" or "chickpea", a close relative of the P. icadius larval foodplant.
In the Altai Mts the Dzhungarian chickpea is known also from the territory of Kazakhstan from the Southern Altai Mt. Range: by the Takyrka River (a Kaldzhir River tributary), and in the Bazar River valley (Krylov, 1933). These localities are about 130 km SW of our one and should resemble it much with respect to the natural conditions. This plant seems to be absent from lower and more dry mountains of the Kazakh Altai as being an element of the vegetation of the upper part of the forest belt, although of a type rather asocial and pertained to barren detrituous slopes. Thus, the Altaian population of the chickpea blue is separated from the closest Tarbagataian one with a considerable gap. Most probably, the species should occur in the Chinese Altai. So, the problem of the geographic limits and geographical distinctness of the subspecies under description remains open unless a comparative material from there were available.
It is interesting that in the region studied practically all the females of Polyommatus icarus had the same deep violet-blue colour of wing upperside (Fig. 2 i, j) as the majority of females of P. icadius (yet they can not be confused!), that well characterized a subspecies recently described from the mountains of South Siberia, Polyommatus icarus korshunovi P.Gorbunov, 1995 (Korshunov & Gorbunov, 1995) [AN ERROR IN THE PUBLLICATION due to my fault. This is not ssp. korshunovi P. Gorb, which is in fact described from Central and South Tyva nad has other characters]. Maybe it is conditions of physical environment (temperature?) in this region similarly influence these two very close species. The fact that on 20th - 21st June the brown females were mostly fresh while the blue ones mostly very worn out is rather in favour of this supposition. On the other hand, the absence of transitory specimens stands for the contrary.
Lastly, let us note that R. V. Kamelin (1998) recently put forward a supposition that the Dzhungarian chickpea in the Dzhazator valley is a result of an ancient (dated the Late Quaternary) unconcious introduction by man. The discovery of its strict monophagous species evidences against this supposition, as occasional carrying not only seeds but plants as a whole (together with butterfly eggs) seems to be much less probable.
First of all the authors express their gratitude to ornithologists Sergei Tsybulin and Maxim Grabovskii for a great help in the field during their expedition to SE Altai. Besides, V. Ivonin thanks Y.P. Korshunov, O. Kosterin thanks V. Dubatolov for promotion of their participation in the expedition and both thank Y.S. Ravkin for a permission to join this expedition of his laboratory.
Artemov, I. A. [Flora of the Katunskii Mt. Range (Central Altai)]. Novosibirsk, 1993, 113 p. (in Russian)
Dyachenko, S. A. [Synopsis of flora of the Plateau Ukok]. In: Flora and Vegetation of Altai. Transactions of the South Siberian Botanical Garden. I. Barnaul: Publishers of the Altai State University, 1995. p. 85-106 (in Russian)
Groum-Grzhimailo, G. Le Pamir et fauna Lepidoptera logiqwe. Memories sur les Lepidoptera. Ed. Romanoff, N. M. St-Petersburg. 1890, T. 4, p. 1-402.
Zhdanko, A. B. Polyommatus icadius (Lepidoptera, Lycaenidae), its taxonomy, biology, and distribution. Zoologicheskii Zhurnal. 1993, Vol. 72, Iss. 7, p. 80-83. (in Russian)
Kamelin, R. V. [Materials on the History of the Flora of Asia (the Altaian Mountain Country)]. Barnaul: Publishers of the Altai State University, 1998. 240 p. (in Russian)
Korshunov, Y., P. Gorbunov. [Butterflies of the Asian part of Russia. A handbook]. Ekaterinburg: Ural University Press. 1995, 202 p.
Krylov, P. N. Flora Sibirea Occidentalis. VII. Rosaceae-Papilionaceae. Tomsk: [Press of the Tomsk Botanical Department of All-Russian Society of Nature Explorers], 1933, p. 1149-1817. (in Russian)
NOTE: the figure setting and numeration do not coincide with those in the original publications, but the very figures are the same
Fig. 1. A female of Polyommatus icadius cicero ssp. n. in natural conditions. DZHAZATOR, 21st July 1998.
Fig. 2. Butterflies: a, b - Polyommatus icadius cicero ssp. n., the holotype (a male);
Fig. 3. Female genitalia of Polyommatus icadius cicero ssp. n. The paratype, Dzhazator, 21st July 1998.