Australian occurrences of moths in the genus Tetraschalis (Lepidoptera: Pterophoridae) are distributed down the east coast from around Cairns to the north-eastern corner of Victoria.
At present (July 2026), the Australian Faunal Directory and Atlas of Living Australia include these records under the species Tetraschalis arachnodes Meyrick, 1887, with Trichoptilus inclitus Lucas, 1892 as a synonym. The closely related Tetraschalis lemurodes Meyrick, 1907 is found across the Torres Strait in New Guinea. The species currently known as Oxyptilus causodes Meyrick, 1905 has been found interspersed with Tetraschalis specimens in Australian collections and (based on female genitalia, general habitus, abdominal pattern and overall colouration) may be related to Tetraschalis.
Based on specimen review in ANIC and using iNaturalist observations, it seems clear that lemurodes occurs at least in Far North Queensland. Occurrences from Brisbane and to the south (as far as north-eastern Victoria) seem to be arachnodes (== inclitus). The few Australian occurrences of causodes are from Far North Queensland and the Top End of the Northern Territory.
The original descriptions for all taxa are included at the end of this post.
Separating the species
The available records show that there is significant variation in the markings and colouration of arachnodes and lemurodes, although the two species can readily be separated in well-marked individuals. Structural aspects are also sometimes difficult to assess. As with many other plume moths, the shape of the forewing can be obscured by angle, rolling of the segments and the breadth of the fringes.
More review is required to confirm whether the species overlap in south Queensland, but the specimens in ANIC (for which structural aspects are easier to assess) seem to divide cleanly between with arachnodes from the Sunshine Coast south through New South Wales, and with lemurodes from regions north of Mackay. The iNaturalist observations show the same geographic break in distribution between northern and southern records and, to the extent that this can be judged, the images are compatible with the same assigment (arachnodes to the south and lemurodes to the north).
Tetraschalis arachnodes Meyrick, 1887
Currently the most southerly record in iNaturalist is this individual from Mallacoota in Victoria. It shows the following characters:
- The wings and abdomen appear disproportionately long.
- The four black-scale teeth (two on each hind-wing) show clearly.
- The ground colour is greyish brown.
- The pale forewing markings matching those in Meyrick’s description for arachnodes (“a cloudy narrow white band on base of first segment, a broader one at its middle, and a narrow one at three-fourths”).
- The antennae are not dark
- The scale-tufts on the forelegs are very bushy.
- The first forewing segment dilates a little after the cleft and has a visible termen with a clear tornus (angle).
- The second forewing segment is also moderately broad (relative to lemurodes).
This record from Brisbane in south Queensland shows a reddish individual, and in particular the bushy tufts on the legs are reddish-brown and contrast with the colour of the tibiae. This seems to be a good character for arachnodes. This insect also shows the whiteness of the antennae. However, although the shape of the first lobe remains clear, the second lobe appears narrow, perhaps as a result of angle or rolling.
This insect from Lismore in northern New South Wales is much more fuscous. Although the shape of the first forewing lobe is again clear, the colouration on the lobe resembles that of typical lemurodes.
Tetraschalis lemurodes Meyrick, 1907
One of the most northerly Australian records for the genus is this individual from the Lockhart River in Far North Queensland. It
Original descriptions
Tetraschalis Meyrick, 1887
Meyrick, E. (1887) On Pyralidina from Australia and the South Pacific. Transactions of the Entomological Society of London 1887: 267:
TETRASCHALIS, n. g.
Forehead without tuft. Antennae minutely ciliated (1⁄4). Palpi moderately long, ascending, with appressed scales, terminal joint long, filiform. Tibiae tufted with scales on origin of spurs. Fore wings bifid, cleft from middle; veins 2 and 4 stalked, 3 absent, 5 and 6 very short, 7 from below angle of cell, long, 9, 10, and 11 out of 8. Hind wings trifid, third segment with tuft of black scales in dorsal cilia; vein 2 from middle of cell, 3 absent, 5 and 6 very short, 7 to apex.
Allied to Oxyptilus, but distinguished by having vein 11 of the fore wings rising out of the stalk of 8, 9, and 10.
Tetraschalis arachnodes Meyrick, 1887
Meyrick, E. (1887) On Pyralidina from Australia and the South Pacific. Transactions of the Entomological Society of London 1887: 267-268:
Tetraschalis arachnodes, n. s.
♂, 21—24 mm. Head, palpi, thorax, and abdomen light brownish-ochreous, mixed with whitish, reddish, and dark fuscous scales. Antennae whitish. Legs very slender, whitish, irrorated with reddish-fuscous, anterior and middle pair tending to be longitudinally striped. Fore wings with segments linear, first slightly, second posteriorly moderately dilated, pointed; reddish-fuscous, sprinkled with whitish and irrorated with dark fuscous; a cloudy narrow white band on base of first segment, a broader one at its middle, and a narrow one at three-fourths, two latter also indicated on second segment; cilia grey, irregularly mixed throughout with black scales. Hind wings cleft firstly from one-fourth, secondly from near base, segments linear; fuscous, third segment dark reddish-fuscous; cilia grey, third segment with a few black scales on upper margin, on lower margin with a tolerably continuous row of close black scales from near base to apex and a fringe of white hair-scales, a large triangular tooth of black scales beyond middle and another at apex.
Newcastle, New South Wales; two specimens, in indifferent condition (Australian Museum).
Trichoptilus inclitus Lucas, 1892
Lucas, T.P. (1892) On 34 new species of Australian Lepidoptea, with additional localities, &c. Proceedings of the Royal Society of Queensland 8: 94:
TRICHOPTILUS (?) INCLITUS, sp.nov.
♂ ♀. 23-26 mm. Head fuscous, closely irrorated with ochreous. Palpi dark fuscous. Antennae ochreous fuscous. Thorax fuscous grey, irrorated with ferruginous fuscous. Abdomen ochreous fuscous, longitudinally streaked with grey, black and fuscous. Tibiae alternately banded light ochreous, fuscous and dark fuscous, anterior pair specially thickened with scales on origin of spurs. Forewings cleft from before middle, segments linear, ferruginous ochreous with dark fuscous, darker toward hindmargin; an ochreous white spot on costa at ⅚. Cilia smoky-grey, on costa narrowly based with fuscous ochreous, darker toward apex; 2nd segment with cilia of darker shade toward base. Hindwings cleft first from before ⅓, secondly from base, segments linear, ferruginous fuscous. Cilia of 1st and 2nd segments smoky grey; 3rd segment darker ferruginous with black cilia.
This appears much the largest species of the genus taken in
Australia. Mr. Boyd of Toowoomba found the first specimen
and Dr. T. L. Bancroft found a second near Brisbane which unfortunately got damaged by ants.
Tetraschalis lemurodes Meyrick, 1907
Meyrick, E. (1908) Notes and descriptions of Pterophoridae and Orneodidae. Transactions of the Entomological Society of London 1907: 476:
Tetraschalis lemurodes, n. sp.
♂ ♀. 23-24 mm. Head, palpi, and thorax dark reddish-fuscous sprinkled with blackish and whitish. Antennae grey, above dotted with black and white scales. Abdomen very long and slender, dark reddish-fuscous sprinkled with whitish. Legs dark reddish-fuscous lined with white. Fore-wings very narrow, cleft from ⅓, segments almost linear, second segment with tornus slight but distinct, its apex extremely slender and elongate ; dark reddish-fuscous sprinkled with whitish ; first segment with a broad band of whitish suffusion beyond its middle, and a narrow fascia towards apex, sometimes also much suffused with whitish anteriorly : cilia dark fuscous, on costa whitish with several dark fuscous patches, on lower margin of first segment with some scattered white and black scales, on both margins of second segment irregularly mixed with black scales. Hind-wings cleft firstly from ⅕, secondly from near base, segments linear ; dark fuscous ; cilia dark fuscous, on upper margin of third segment with scattered black scales, on dorsum much mixed with black and white scales from base to apex, forming a rather longer and more conspicuous accumulation beyond middle.KEI ISLANDS, in April and May; two specimens.
Oxyptilus causodes Meyrick, 1905
Meyrick, E. (1905) Descriptions of Indian Microlepidoptera. Journal of the Bombay Natural History Society 16: 582:
Oxyptilus causodes n. sp.
♂ ♀. 20 — 22mm. Head, thorax, and abdomen dark reddish-fuscous, face without tuft. Palpi long, slender. Forewings with segments narrow ; dark reddish-fuscous, slightly sprinkled with whitish-grey, especially on first segment ; an ochreous-whitish costal dot or small spot at middle of first segment, and a slender ochreous-whitish bar near its apex ; cilia fuscous, with numerous scattered blackish scales, forming a bar at lower angle of tip of first segment, rounded dark fuscous black-edged spots at tip of second and tornus, and two undefined projections on its dorsum. Hindwings with segments linear ; dark fuscous; cilia fuscous, on third segment mixed with black scales at base on both margins, with a large triangular black scale-tooth on lower margin at 3⁄4, and a small one beneath apex.
Nine specimens, Peradeniya, Ceylon, in August and October (Green). Larva feeds in fleshy fruits of Dillenia retusa, in August ; when about to pupate, it leaves the fruit and attaches itself to any neighbouring support (Green).
