NATURE NOTES THE SPHINX MOTH

Press, Volume LXXIV, Issue 22435, 23 June 1938, Page 6 (Supplement)

NATURE NOTES THE SPHINX MOTH

i The Sphinx was a person of : ancient mythology who went about ; poring ’people by asking them 1 f ..-riddles. H they could not give the ■/ right answers,; he very promptly ( ; ate them up. Although Linnaeus : ' gave the name of Sphinx to a ' group of moths because he saw a : resemblance in the resting attitude of the larvae to the Egyptian Sphinx there are other. resemblances. These insects present us with three riddles. Why should the moth have such a long tongue? Why should' the caterpillar wear a hom at the tail-end where horns are useless? Why dpes the pupa look like a jug with a handle but no spout? Afl of which is suggested by the fact that the pupils of the Reeftofc

; ■ *chool sent me some weeks ago a p very large caterpillar (B), which they had found in the ground. I kept it in soil in a dish and in a few days it turned into a peculiar pupa (C). If all goes well in the spring /it should emerge in the shape of a magnificent moth like the one sketched at (A). The species of sphinx moth found in New Zealand is. usually known as the convolvulus moth because the larva feeds on the leaves of convolvulus or other plants of. the same family. The horn on the rear end is an absolutely harmless projection; it neither stings nor poisons anything. When disturbed or when at rest the caterpillar has a habit of rearing up the front part of the body as shown at (A). Whether they are meant to look threatening .or ferocious in this attitude could .; .only be decided by their natural / enemies such as birds. When restJ ing'they may remain in this posi- •' tion for hours at a time, quite ■ motionless. The six true legs on f the thorax are very short ahd • furnished with small'-sharp claws . which hold the edges of the leaf in a suitable position for the jaws to ' cut it freely. The four pairs of i fleshy legs or foot stumps are used for holding on to the twig or leaf. : On the tail end is a large fleshy : loot stump which can clasp a twig firmly like a vice;

(By L. W. McCaskill)

When the caterpillar is full grown it descends to the ground and burrows into the earth. It does not spin a silken cocoon, but makes a. smooth-walled earthen cell in which it changes to the pupa. The "jug handle" encloses the long tongue found in the adult moth. In the spring the pupa wriggles its way to the surface and the moth emerges. The expansion of the wings is about 3iin. The lorewings are grey, dark speckled, with several darker grey marks. The hindwings- are greyish-black with several handsome dark markings. The head and thorax are dark grey. The abdomen is grey with stripes of white, black, and red.

Adult moths may appear in November and December. They fly with remarkable swiftness at dusk, hovering over the. flowers and, while poised in the air, extracting the nectar with the long tongue. The long tongue or proboscis is specially suited to getting nectar from flowers such as convolvulus, honeysuckle, petunia, or nasturtium which have long tubular nectaries or corollas. Many orchids in other countries are visited by sphinx • moths, whose long tongues can reach down to the foot of the long spur in which the nectar is secreted. Alfred Russel Wallace showed that the length of the moth’s tongue may be exactly suited to the length of the nectary tube of the orchid regularly visited. Later on he became acquainted with an orchid from Madagascar with a nectar-spur nearly llin long. This was much longer than the tongue of any known moth. But Wallace had great faith in Nature. He prophesied that a moth would be found with a tongue long enough to reach the nectar. “That such a moth exists in Madagascar may be safely predicted and naturalists who visit >that island may search for it with as much confidence as astronomers searched for the planet Neptune—-and I venture to predict that they will be equally successful.”

Many years passed and then someone discovered a moth in Madagascar with a tongue just the right length.