Art. XXXVA.—On Macro-lepidoptera observed during the Summer of 1903–4, including a Note on the Occurrence of a Hawk-moth new to New Zealand.
[Read before the Wellington Philosophical Society, 6th July, 1904.]
Mr. R. I. Kingsley records having seen this butterfly in his garden at Nelson on the 6th January, 1904.
This butterfly, which is usually very rare in New Zealand, occurred in considerable numbers in various parts of the country during the past summer. The Rev. Alex. Doull, of Otahuhu, to whom I am indebted for the fine series of specimens exhibited this evening, informs me that during the end of February and beginning of March he saw no less than fifteen specimens, and succeeded in capturing seven on a flowering shrub (Escallonia floribunda) in his garden. The occurrence of Diadema bolina at Wanganui in March was reported by Mr. Ritchings Grant, and at Nelson by Mr. R. I. Kingsley, who stated that he had seen seven specimens, and heard of others.
I have noticed, since my garden at Karori has become more sheltered through the growth of trees, that this butterfly is much more abundant there than formerly. Last summer it was very common, and one warm night in January I discovered, by means of a lantern, no less than six individuals
asleep. The butterflies were simply perched on the outside foliage of a macrocarpa tree, and were quite readily seen, though the bright-yellow colouring of the closed wings suggested a faded leaf. This resemblance would, however, afford the insect very efficient protection whilst resting asleep amongst the foliage of many of the native shrubs, the faded leaves of which are, in many instances, yellow in colour. In such situations its destruction by nocturnal enemies would, no doubt, thus be largely obviated.
This insect is generally very irregular in its appearance. Last summer, however, it was reported by Mr. Grant as very plentiful at Wanganui, and by Messrs. F. G. Gibbs and R. I. Kingsley as abundant in the Nelson District.
Chærocampa celerio, Linn. Plate XXII., fig. 1.
Four specimens of this insect, which, so far as I am aware, has not been previously met with in New Zealand, were taken in Nelson last summer—one specimen, apparently the first, by Mr. Kingsley the week before Christmas, another by Mr. Frank Whitwell shortly afterwards, a third by Mr. Edward Mules on 24th February, and a fourth by Mr. Gibbs a few days later. The occurrence of this insect in New Zealand is of excessive interest, as prior to this discovery the family Sphingidœ was only represented in this country by a single, almost cosmopolitan, species, i.e., Sphinx convolvuli. It will be interesting to see if the newcomer is permanently established, and collectors should be specially on the watch to detect further specimens.
The expansion of the wings is about 3 in. The fore wings are brownish-ochreous, with short black and silvery longitudinal lines, and a shining silvery wavy streak, divided by two fine brownish lines running from the base of the dorsum to the apex, below which are whitish longitudinal lines running along the dorsum. A little below the middle of the costa is a black spot in a pale ring. The hind wings are rose-colour, with the termen and a central streak broadly black. The intermediate rosy band is also divided by black veins. The larva is green or brown, with black eye-like markings on the fifth and sixth segments, with white pupils, and enclosed in slender yellow rings. The horn is slender and long and straight. The larva feeds on the vine.” (Kirby.)
C. celerio occurs rarely in Britain south of the Caledonian Canal, and in the north of Ireland, but only as an occasional immigrant. It is a very widely distributed species, otherwise ranging through west, central, and southern Europe, south Asia, Africa, and Australia.
An additional food-plant for the larva of this insect is the wharangi (Brachyglottis repanda). (See “New Zealand Moths and Butterflies,” page 83.)
The following is the life-history of this species: The egg is oval, flattened at one end, pale sea-green, covered with numerous very slight hexagonal depressions. It is highly polished, with a large oval depression on each side of its long axis. As the enclosed embryo develops, small irregular reddish-brown patches appear on the surface of the egg-shell.
The larva, which feeds on tree-ferns (Dicksonia), is, when full-grown, about 1¼ in. in length and of uniform thickness throughout. The general colour is pale rusty-brown with an obscure pale-brown dorsal line, stronger on the thorax and at the commencement of each segment. There are two similar obscure lateral lines. The head is yellow, thickly dotted with dull-red, and the entire larva is thickly dotted with dark-brown dots and clothed with pale-reddish hairs. There are several obscure marks near the spiracular region.
This larva is very sluggish and grows slowly. It probably emerges from the egg in the autumn, hibernates during the winter, and feeds from September till the middle or end of December. It then finally buries itself in the earth and changes into a pupa, the moth appearing a month or six weeks later. (See “New Zealand Moths and Butterflies,” p. 98.)
I find that my report of the occurrence of this species at Wainuiomata, recorded in the “Transactions of the New Zealand Institute,” vol. xxxii., p. 11, is erroneous, having been founded on a mistaken identification.
The larva of this species, which feeds on the common Veronica in December, is, when full-grown, about ¾ in. in length, rather attenuated anteriorly, almost uniform, dark reddish-brown, darker on the sides. The head is reddish, and there are traces of several longitudinal lines in younger larvæ. Others are dull yellowish-brown, with the lines plainer and the prolegs pale-yellow; but as the larva is so extremely variable a detailed description hardly appears possible. The pupa is enclosed between two leaves of the Veronica, fastened together with silk. The moth emerges at the end of January. (“New Zealand Moths and Butterflies,” p. 42.)