1964 ] ournal of the Lepidopterists' Socicty 3.5 THE MATING TIME OF LEPIDOPTERA by GEORG PRONIN From an oId balcony of our house in Osanovo, Russia, one could see a large meadow which was densely covered with grass, clover, daisies, and sorrel. Among this vegetation were bunches of rosy wild carnations and blue-bell flowers. Farther away the meadow changed into an elder grove, with bunches of wild hops, raspberries, and flowering cherries (Prunus padus). The old basswood garden was joined to the young birch groves at the other side of the old house. Close to this side of the wooden house was a young grove of aspen trees. The dense branches of lilac and acacia were growing directly against the windows of the house. On the balcony a young boy sat motionless, looking very attentively at an old wire cylinder in which a big female moth was fastened. This female belonged to the northern race, Gastropacha qucrcifolia alnifolia, which has a dark violet shade over its brown ground color and is native in Moorom Woods of the government of Vladimir in Russia. Extending her heavy thick abdomen, the moth patiently waited for the males which were certainly flying around the house. The evening was going its way. The redness in the sky changed slowly into the bright summer night's twilight, as is common in the north. The night was silent; only the grating voice of the Com Crake was coming from the large spaces of wet meadows, and the com fields sent the biting cry of the quail. Suddenly a little shadow of a male moth was seen coming from the roof of the house. The boy moved too quickly, and the night visitor flew high up and disappeared. After that, although the young enthusiast sat near his moth in the wire cylinder evening after evening, nothing happened. Only one male was seen at the cage. These moths have no mouthparts and therefore can not take food. The only task which the adult males have is to find and fertilize females. Perhaps this female was not attractive to the males, but the boy could not believe that. Another female of this species was bred from a large, gray caterpillar which had been found sitting on a low willow branch. When disturbed, it showed large dark blue hairy brushes near its head. The caterpillar made a hairy cocoon, changed into a pupa, and after nearly three weeks hatched into a robust G. qucrcifolia female. Evening after evcning, beginning as late as nine 0' clock, the young entomologist sat hour after hour waiting in vain for attracted males. Everything seemed all right, but something was wrong. As four days passed, the female began to lay her eggs and on the fifth day she died. N early twelve years later, in another part of the country, more to the 36 PRONIN; Mating times VoLl8; no.1 west in Luck, Wolhyn [now Lutsk, Volyn, RussiaJ the young entomolo­ gist was again sitting at a wire cylinder which enclosed another female of the C. quercitolia. A big fruit garden surrounded the observation spot. The wire cage was put on the top of an old wooden box which once served as a beehive. The observation had begun at eight o'clock and at 8:45 three males were attracted. Evening after evening the entomologist collected the males which were attracted from 8:45 for a period of only seven or eight minutes. After this very short time no more males were seen. The question was answered. The young boy had begun his observations in Osanovo too late in the evening, when the courtship flight period of the males had already ended. The males of the moth Philudoria potatoria are very similar to those of C. quercitolia. The young collector was very familiar with them in his old basswood garden, and had often placed a female of P. potatoria on a branch in the garden but never found a male there before nearly ten 0'clock. The boy had thought that the mating hours of C. quercitolia would also be late, but the analogy is not the proof. The mating hour of C. quercitolia is 8:45, and of P. potatoria 10:35. But we must not be too severe with the boy for his error. The old genial entomologist, Henri Fahre, also made such a mistake. He waited in vain for the coming of the male Lasiocampa tritolii during the bright sunshine, guided only by the resemblance of the caterpillars of trifolii to those of L. quercus, which visits its female between two and four PM daily. The sexual flight of L. tritolii is at nine in the evening. We must distinguish the flying hours from the mating time, because they are not the same. For example, many hawk moths, which have tongues for sucking nectar, fly at twilight to feed but have their mating hours later, after feeding. The common European sphingid, Laothoe populi, begins flying after 9 PM and the mating hours are after midnight. Perhaps another reason for this is that the young males thus have time to fly very far from the place of their birth and this makes mating with their sisters improbable. Here is a short table of mating hours observed for different moths: THE MATING TIME OF MOTHS Species Time Month Locality Hyalophom euryalus Bdv. 10:30 PM VI Shasta Co., Calif., USA Saturnia pyri Schiff. 10:30 PM V Bosporus, Turkey Saturnia pavonia L. 2-4 PM V Munchen, Germany Aglia tau L. 11-12 AM V Bayerbrun, Germany Endromis versicolora L. 11-12 AM IV Vladimir, Russia Macrothylacia rubi L. 4-6 PM VI Vladimir, Russia 1964 ] oumal of the Lepidopterists' Society 37 Lasiocampa quercus L. 2-4 PM VII Luck, Wolyn, Russia Lasiocampa trifolii Schiff. 9 PM VIII Miinchen, Gennany Lasiocampa grandis Rougeuh 8:45 PM VIII Bosporus, Turkey Lemonia dumi L. 11-12 AM Luck, Wolyn, Russia Lymantria dispar L. 11-12 AM VIII Luck, Wolyn, Russia Philrudoria potatoria L. 10:35 PM VII Luck, Wolyn, Russia Gastropacha quercifolia alnifolia O. 8:45 PM Luck, Wolyn, Russia Epicnaptera americana Harris 9:30 PM VII MalYs Peak, Ore., USA Orgyia antiqua L. 10-12 AM VIII Vladimir, Russia Orgyia gonostigma F. 11-12 AM VII Luck, Wolyn, Russia Laothoe populi L. 12:33 AM VII Luck, Wolyn, Russia Smerinthus ocellatus L. 11-12 AM VII Luck, Wolyn, Russia M imas tiliae L. 10:15 PM VI Vladimir, Russia 9:15 PM VI Kharkov, Russia 7:15 PM V Bosporus, Turkey Deilephila elpenor L. 9:45 PM VI Luck, Wolyn, Russia Sphinx liqustri L. 11:30 PM VI Miinchen, Germany Arctia caia L. 11 PM VII Luck, Wolyn, Russia Eriogaster rimicola Hbn. 10 PM VIII Luck, Wolyn, Russia Catocala elocata Esp. 8:15 PM IV Luck, Wolyn, Russia Psyche unicolor Hufn. 11-12 AM VII Praha, Czechoslovakia Fumea casta Pall. 6 PM; 4AM VII Luck,Wolyn, Russia Aegeria apiformis Cl. 11-12 AM VI Vladimir, Russia Such a table must always have the locality, date, and thc time of day. The locality gives us the possibility of detennining the meridian correlation. An example of the importance of these data is the difference in mating times of M imas tiMae, which begins to fly to his female in North Vladimir at 10:15; in Kharkov at 9:15, and in Bosporus, Turkey, at 7:15 PM. This phenomenon may be connected with the beginning of dew condensation. An unusual mating time was observed in a pair of Smel'inthus kindermanni. An old male was stored in a semi-dark cellar for about 6 days until a female was hatched. When he was put into the box with her, they began to mate at once, at 2 PM in daylight. It may be significant that the pupae had been brought from southern Iran, and the mating took place in Lodz in central Europe. The mating time can be short, as observed in Lasiocampa grandis, whose caterpillar is similar to that of L. quercus. This species lives at Bosporus near Istanbul, Turkey, and I have reared it. One evening one of the big brown males came in through an open window and flew around the electric lamp. In my rearing box were two females. When 38 PRONIN: Mating times VoLl8: no.1 I took the box out into the garden, it was at once surrounded with a small swann of males. This was at 8:45 PM and lasted only 4 or 5 minutes; then the entire lot of males flew away. The mating time of Hyalophora euryalus, which I observed in Shasta County, California, is not short. The pupa of a female of this species had overwintered in her cocoon in an open wire cage at Hat Creek. The conditions were normal, and she hatched on June 5. I put her into a box with walls of tulle netting and took a seat at the beginning of twilight on the balcony of the Hat Creek Entomological Station. At almost 10 PM I could see one male after another flying continuously around the box. One male came very near to the box and after inquiry with his antennae he also flew away. Did the males know that the female was surrounded on every side by tissue? I could not tell. But to permit the female to mate without giving her the chance to escape I very carefully cut her wings so she could not fly, then placed her in a tall wide-mouthed jar, left it on the balcony, and went to sleep.