The Queen of Spain Fritillary (Argynnis Lathonia)
In shape and in general appearance this butterfly is not unlike a small example of the Silver-washed Fritillary; the large silvery, or sometimes pearly, blotches on the under side of the hind wings at once reveal its higher British rank. When flying it has a curious resemblance to the Wall, and sometimes it has been taken when the captor supposed that he was netting a specimen of that plebeian butterfly. The black markings on the upper side vary somewhat in size, and occasionally those on the front area, or those on the inner area of the fore wings, are more or less confluent; very rarely the wings are suffused with a steely-blue or bronze colour. The specimens occurring in this country do not, however, exhibit so much variation as has been observed in this butterfly abroad.
I have not seen any of the early stages. The figures of the caterpillar and the chrysalis (Plate 58) are after Hübner, and the following descriptions of the egg and other stages are adapted from the detailed life-history of the species by Mr. Frohawk, published in the Entomologist for 1903:—
“The egg is one-fortieth of an inch high, of a rather straight-sided conical form, widest at the base, where it is smooth and rounded off at the edge. There are about forty longitudinal keels, irregularly formed and of different lengths, some not reaching halfway up the side, and others running the entire length from base to crown, where they terminate abruptly, and form a series of triangular peaks round the summit surrounding the granulated micropyle; the spaces between the keels are finely ribbed transversely. When first laid it is of a very pale lemon-yellow colour, inclining to ochreous, appearing almost white in certain lights; the colour gradually deepens, becoming yellower with a greenish tinge. On the fifth day the crown of the egg assumes a dull grey, finally changing to a lilac-grey.”
The female butterfly, when placed in the sunshine, laid about a hundred eggs during the day—August 7. These were mostly placed singly on the leaves or other parts of a plant of heart’s-ease (Viola tricolor), but some were laid on the gauze cover of the cage. All the caterpillars hatched out on August 14.
The caterpillar when full grown is velvety black, densely sprinkled with tiny white dots, each bearing a black bristle; there are six rows of spines, which are of various shades of brown with yellowish bases and shining black bristles; along the back there are two white streaks on the fore part of each ring, and white warts emitting black bristles on the hind part. The head is amber-coloured above, but black below, and is covered with bristles like the body.
The chrysalis has the head, thorax, and wing-cases shining olive-brown; the body chequered and speckled with olive-brown, ochreous, black, and white. The spiracles are black and conspicuous, and the points on the body are amber-coloured. The thorax and first two body rings have brilliant burnished silver-gilt ornamentation.
The butterflies commenced to emerge on September 25, and between that date and the 28th ten came out. Although he succeeded in rearing almost all the caterpillars to the chrysalis, no less than eighty died in this stage, and he states that “there is no doubt that the late autumn English climate is quite unsuited for the existence of this species,” as well as for others that come to us from abroad.
Moses Harris, in 1775, gave this butterfly the name “Queen of Spain;” it had been known to English entomologists from 1710 until then as the “Lesser Silver-spotted Fritillary.” Gamlingay in Cambridgeshire seems to have been the only British locality in which it had been observed until 1795, when Lewin mentions a specimen taken in a Borough (London) garden in August. All the Cambridge specimens had been captured in the month of May. Stephens, writing in 1828 (“Ill. Brit. Ent. Haust.,” i. 37), says—
“Previously to the year 1818, few cabinets possessed even a single specimen; and from the very few known instances of its capture (six only, according to Mr. Haworth), there is reason to believe that some of the specimens at that time [1803] placed in collections were foreign; but in the above remarkable year for the appearance of certain papilionaceous insects, this species occurred simultaneously in several, and very distant, parts, having been taken in August by Mr. Haworth at Halvergate, in Norfolk; by Mr. Vigors in Battersea-fields; by myself at Dover, and, during that and the following month, near Colchester; Birchwood, Kent; and Hertford in plenty by others. At the latter place I saw several specimens, but was not fortunate enough to secure any.”
The butterfly has been taken, chiefly odd specimens, in many of the eastern and southern counties, from Norfolk to Dover, and almost always in the autumn. It has also occurred at Scarborough (1868), and at least once in Ireland (1864).
The neighbourhood of Dover seems to have always been the most favoured locality, and no less than twenty-five specimens were captured there in 1882. Several examples were also obtained at Dover in 1883, and a single specimen in other parts of Kent in 1884 and 1885. The most recent records are—Brighton, one example in 1892; Clifton, one in July, 1898; Christchurch, one in August, 1899; Poole, one in 1901. There does not seem to be any authentic record of the caterpillar having been observed in Kent or any other British locality in which the butterfly has been noted. This may possibly be due to its love of concealment.
There are two flights of the butterfly in the year, one in the spring and the other in the autumn.
Females from the Continent may arrive on our east or south coasts in May, and deposit eggs from which the autumn butterflies are developed. Some of these might wander farther inland, but eggs would almost certainly be laid on the spot. The fate of the caterpillars from autumnal eggs would depend on the winter; if mild they, or at least some of them, might manage to get through and attain the butterfly state about May, but their doing so is rather doubtful.
The species is widely distributed and often common on the Continent, and its range extends to Persia, Northern Asia, and North Africa. In Eastern Asia it is represented by var. isœa.