Family 4. ORTHOSTIXIDAE.

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"Hind-wings with vein 5 fully developed, rising from about middle of transverse vein, 8 connected with upper margin of cell by an oblique bar towards base."—(Meyrick.) (See Plate II., figs. 46 and 47.)

This small family is represented in New Zealand by a single genus only. The peculiar oblique bar connecting vein 8 with the cell towards base, combined with the development of vein 5, distinguish it from all other families. If there is any chance of confusion with those forms of HydriomenidÆ in which vein 8 is also connected by a bar (though in them the bar is placed beyond and not before the middle of cell), the absence of the characteristic areole of the HydriomenidÆ will be a further test.

Genus 1.—EPIRRANTHIS, Hb.

"Face with appressed scales. Tongue developed. Palpi very short or moderate, porrected or subascending, rough-scaled. AntennÆ in male evenly ciliated. Thorax rather hairy beneath. Femora glabrous; posterior tibiÆ with all spurs present. Fore-wings with vein 10 anastomosing with 9, 11 anastomosing with 12 and 10 before 9. Hind-wings with 6 and 7 separate."—(Meyrick.) (Plate II., figs. 46 and 47, neuration of Epirranthis alectoraria; fig. 48, head of ditto.)

Represented in New Zealand by two species.

EPIRRANTHIS ALECTORARIA, Walk.

(Lyrcea alectoraria, Walk. 259; Meyr., Trans. N. Z. Inst. xvi. 95. Aspilates (?) primata, Walk. 1076; Butl., Cat. pl. iii. 4. Endropia mixtaria, Walk. 1506; Butl., Cat. pl. iii. 5. Amilapis (?) acroiaria, Feld. cxxiii. 6. Lyrcea varians, Butl., Cist. Ent. ii. 496. Ploseria alectoraria, Hdsn., Manual N. Z. Ent. 86.)

(Plate VIII., figs. 42, 43, 44, 45, 46, and 47, varieties; Plate III., fig. 24, larva.)

This species has occurred in tolerable abundance at many localities in both the North and the South Islands. It is probably generally distributed throughout the country.

The expansion of the wings is from 1 inch to 1½ inches. The wings range in colour from pale yellow to dark orange-brown, dark reddish-brown, or even dull brown, with innumerable intermediate tints. There is often a central transverse line reaching from the costa of the fore-wing to the dorsum of the hind-wing. Many of the varieties are speckled with darker colour; others have irregular yellow patches, generally situated on the fore-wings just below the apex and on the dorsum near the base; there are often two white dots near the apex of the fore-wings.

Most of the varieties closely resemble the varied hues of fading leaves. In many of the forms greyish speckled marks occur on various parts of the wings, no doubt imitating the irregular patches of mould which are often present on dead leaves. One very well-marked variety is bright yellow, with the costa rosy and two large white-centred rosy spots arranged transversely on each wing. (See Plate VIII., fig. 47.) All the specimens of this insect are so extremely variable that it is almost impossible to adequately describe the species. The apex of the fore-wing is always very acute; the termen is bowed just below the apex, and is furnished with slight indentations of variable depth. The termen of the hind-wing is also furnished with variable indentations.

The egg is oval and much flattened above. When first laid it is pale green in colour, but becomes dull olive-green as the embryo develops.

The young larva is very pale green, with the head brownish-yellow. At this early stage its colouring already completely harmonises with that of the under side of the leaves of its food-plants, Pittosporum eugenioides and P. tenuifolium.

The full-grown larva is very robust, and about 1 inch in length. Its colour is pale green, with numerous yellow dots and a series of diagonal yellow stripes on each segment; there is, in addition, a series of broad crimson blotches on the back and a small crimson flap projecting from the end of the terminal segment; the prolegs and spiracles are also crimson.

The remarkable shape and colouring of this caterpillar, in conjunction with the peculiar attitude assumed when at rest, affords it complete protection, causing it to resemble, in the closest possible manner, one of the buds of its food-plant. These larvÆ grow very slowly, and probably occupy three or four months in attaining their full size. They are very sluggish in their habits. The pupa is greenish-brown in colour. It is enclosed in a cocoon, constructed of two or three leaves of the food-plant, fastened together with silk. The insect remains in this condition for three weeks or a month. The moth first appears about the end of October, and is met with until the middle of March. It frequents forest, where it is occasionally dislodged from amongst the undergrowth. It is also found in the evening on the flowers of the white rata. It is, however, rather uncertain in its appearance, being much commoner in some years than in others.

EPIRRANTHIS HEMIPTERARIA, Gn.

(Hemerophila hemipteraria, Gn. ix. 220, pl. vi. 2. Xyridacina hemipteraria, Meyr., Trans. N. Z. Inst. xx. 60. Ploseria hemipteraria, Hdsn., Manual N. Z. Ent. 85.)

(Plate VIII., fig. 48 ?, 49 ?; Plate III., fig. 19, larva.)

This remarkable-looking species has occurred in the North Island, at Auckland and Wellington. At present it has not been observed in the South Island.

The expansion of the wings is from 1? to 1? inches. All the wings are pale ochreous-brown, with a variable number of minute black dots; there are four or five oblique, wavy brown transverse lines on both fore- and hind-wings, the central and terminal lines being often slightly darker than the others; there is always a black dot in the middle of the fore-wing, and a shaded spot near the termen below the apex. The apex of the hind-wing is very pointed and projects downwards; the almost straight termen has a series of prominent projections.

This species varies much in the intensity of the markings, and in the number of the black dots on both the fore- and hind-wings. The peculiar outline of its hind-wings, however, distinguishes it from any other species with which I am acquainted.

The larva feeds on veronicas in September and October.

Its length when full grown is about 1 inch. Some larvÆ are green, with a broad bluish dorsal line, and two fine yellow lateral lines. Others are brown, with a dull yellow dorsal line.

During the daytime these caterpillars firmly clasp the stem of their food-plant with their prolegs, and hold the rest of their body rigidly out from the branch. In this position they are very inconspicuous, and may readily be mistaken for young leaves or twigs. At night they become much more active, and may then be seen walking about and feeding.

The pupa is rather robust, with a sharp spine at its extremity. Its colour is pale olive-brown, with the wing-cases and sides of the abdomen pinkish. It is not enclosed in any cocoon, but is merely concealed amongst the dead leaves and rubbish around the stem of the veronica. The insect remains in this state for less than a month, so that the protection of a cocoon would appear to be unnecessary.

The moth appears in December and January. It usually frequents gardens and other cultivated places, probably on account of the number of veronicas that are often growing in such situations. It is also attracted by blossoms and by light, but is not a common species. The colouring and wing-outline of this moth cause it to very closely resemble a dead leaf, especially when resting amongst foliage or on the ground. This insect may be occasionally noticed abroad on mild evenings in the middle of winter; the females probably hibernate and deposit their eggs early in the spring.

                                                                                                                                                                                                                                                                                                           

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