A Life-history Study of the Brown House Moth,Hofmannophila pseudospretella(Staint.) (Lep., Oecophoridae)

Abstract

Hofmannophila pseudospretella is widely distributed in this country. It is a minor pest of stored foodstuffs, clothes and furnishings, and under certain conditions may give rise to a major infestation.The egg stage is characterised by a high sensitivity to temperature and almost complete indifference to humidity. The incubation period varied from 110 days at 10°C. (90 per cent. R.H.) to 8·5 days at 27°C. (90 per cent. R.H.) and from 9·8 days at 90 per cent. R.H. (25°C.). to 14·0 days at 8·5 per cent. R.H. (25°C.). The percentage survival was greatly reduced both at very low (<3 per cent. R.H.) and at very high (100 per cent. R.H.) humidities. The survival of eggs from a single female varied from 56 to 97 per cent. under favourable conditions.The duration of the feeding larval stage varied between 145 days at 13°C. and 71 days at 25°C. (at 90 per cent. R.H. on middlings). Larvae failed to mature below 80 per cent. R.H. at all temperatures. Larvae were reared successfully on a wide range of diets of both animal and vegetable origin, some predominantly carbohydrate, some almost entirely protein. The most rapid development occurred on dead adults and the slowest upon leather and yeast.Under most conditions fully grown larvae entered diapause. This was characterised by a diapause moult after which the larvae assumed a typical diapause appearance. The length of the diapause was extremely variable and was determined largely by the temperature during larval growth. Larvae grown at low temperature did not enter diapause when incubated at 25°C. as fully grown larvae. The diapausing larvae were remarkably resistant to desiccation.The duration of the pupal stage is affected by temperature but not by humidity. It lasted 98 days at 10°C. and 13 days at 28°C.The total length of the developmental period was highly variable because of the variability in the length of the diapause under constant conditions. When the conditions throughout were 25°C. and 90 per cent. R.H. the total developmental period varied between 152 and 266 days, and at 20°C. and 90 per cent. R.H. the figures were 192 to 440 days. The developmental period was approximately 12 months under field conditions.Under crowded conditions, mating was observed between males of H. pseudospretella and females of Endrosis lactella but none of the eggs developed.The weight of the female at emergence was the most important factor governing the number of eggs laid. Weight of females varied between 8·2 mg. and 43·6 mg. and the egg number between 106 and 657 at 25°C. and 70 per cent. R.H. The number laid was significantly reduced at lower temperatures (10°C.) and at lower humidities (20 per cent. R.H.).The sex ratio was found to be approximately 1:1, with a slight predominance of females.The longevity of the fertilised adult female depended upon its weight at emergence and upon the physical conditions. Variation in weights of males was small, and the length of life of mated males could be correlated directly with the physical conditions. The mean longevity of mated females of all weights was 11·9 days at 25°C. and 70 per cent. R.H., 19·0 days at 15°C. and 70 per cent. R.H. and 9·4 days at 25°C. and 20 per cent. R.H. At 25°C. mated males lived 7·1 days on the average, and 18·8 days at 15°C.The only important predator was the mite, Cheyletus eruditus, which destroyed numbers of eggs and young larvae.

Studies on the Bionomics of the Case-bearing Clothes Moth, Tinea pellionella (L.)

“…In the case of the Brown House Moth, Hofmannophila pseudospretella (Stnt. ), a significant correlation has been traced between length of life and the weight of the female at emergence (Woodroffe, 1951).…”

Characterization of lactic acid bacteria in the larval midgut of the keratinophagous lepidopteran, Hofmannophila pseudospretella

“…Hofmannophila pseudospretella (Stainton) (Lepidoptera: Oecophoridae) (brown house moth) larvae are keratinophagous (Woodroffe 1951). They have a similarly low redox potential in the midgut as T. bisselliella but the pH is less alkaline (Christeller 1996).…”

A survey of stored product Lepidoptera in New Zealand

“…sarcitrella requires conditions of <20 D C or 80% relative humidity to complete its life cycle, although individual stages will survive much lower conditions (W oodroffe 19 51 b). It can complete several generations a year in New Zealand, unlike H. pseudospretella which is usually univoltine and which, in northern Europe, overwinters as a fully grown larva in diapause (Woodroffe 1951a). Casual observation of cultures kept at the Lincoln Plant Health Station has shown that H. pseudospretella larvae also enter diapause during the southern hemisphere winter.…”