About Ichneutica lignana
The scientific name of this species is Ichneutica lignana. Morris Watt described the egg of Ichneutica lignana as hemispherical, with flattened top and bottom of equal area, and an overall pearly white color. After approximately one week, a narrow light brown band forms around the egg just above its equator, and a small, irregular light brown patch covers the micropyle. Four days after that, the light brown areas darken significantly, and the rest of the egg's surface becomes light grey. At this stage, the larva is visible inside the egg. Just before hatching, the reticulated patterning on the egg becomes white and very distinct. Hoare provided a description of the species' larva: The head is green, with longitudinal darker green stripes, and is paler green below the stemmata. The body tapers towards the posterior, with no hump on the eighth abdominal segment, and is bright green overall. It has an indistinct, whitish-green dorsal line, bordered on each side by dark green. A broader, conspicuous cream-colored subdorsal line is present, which is only bordered by dark green along its upper edge. The area between the dorsal and subdorsal stripes has pale marbling, which forms faint, indistinct longitudinal stripes. A clear white lateral stripe sits at the level of the spiracles, and is narrowly bordered by darker color along its upper edge. A broad whitish-green subventral area connects to the lateral stripe and contains some darker green mottling; the area below this, including the bases of the prolegs, is green. Pinacula are very indistinct and greyish. Thoracic legs are translucent greenish. Setae are brownish. Spiracles are pale ochre brown with black peritremes. Walker described the adult male of Ichneutica lignana as follows: The body is a very pale fawn color. The third segment of the palpi is no longer than one-fourth the length of the second segment. Antennae are very minutely ciliated. Both the thorax and abdomen have crests. The thorax has faint oblique black stripes, plus two broader humeral stripes. The forewings have faint brown streaks towards the base, three diffuse brown spots along the exterior border, black marks along the costa, and black marginal lunules. The three discal spots are distinct with brown borders. The orbicular spot is oblong and subfusiform, with a brown streak at its base. The reniform spot is not excavated, and has a blackish disk. The submarginal line is pale and irregular, passing through the marginal spots. The hindwings are brownish ash-grey, with pale cilia. The body length is 7 lines, and the wing length is 16 lines. Adult males have a wingspan ranging from 32 to 40 mm, while adult females have a wingspan ranging from 33 to 39 mm. The species is quite recognizable due to its dark markings on the abdomen and forewings. It could potentially be confused with Ichneutica morosa, Meterana pansicolor, and Meterana pascoi, but I. lignana can be told apart from these three species because they do not have the distinct claviform spot that is present on I. lignana's forewings. Ichneutica lignana is endemic to New Zealand. It can be found on the Three Kings Islands, as well as the North, South, and Stewart Islands of New Zealand. The species occupies a wide range of different habitats, including coastal areas, tussock grasslands, shrublands, and native forest. It occurs across a range of altitudes, from sea level up to over 1300 m.
