Publ. 6. IV. 1937. 
HEPIALIDAE. By R. Pfitzner |- 
1289 
Family: Hepialidae. 
By R. Pfitzner f. Revised by M. Gaede. 
A strange group differing from all the other lepidopteral forms and separated by extremely old 
marks of distinction; the “Jugatae” , thus styled by Comstock because of their being provided only with a 
skinny lobe (jugum) instead of the frenulum ( frenatae ), comprise the two families of the Micropterygidae in¬ 
clusive of the Eriocraniidae and Hepialidae (Mieropterygina ). The Hepialidae have developed from the Micro¬ 
pterygidae without any closer relations, as there are no connecting links. The Mieropterygina are the most 
primitive lepidopteral order and, in their neuration, they immediately approximate the Trichoptera. The age 
specially of the Hepialidae is traced back to the Jurassic epoch, when this family may have been represented by 
gigantic forms, lepidopteral “saurians”, only single remnants of which have been left to this day, as for instance 
the gigantic Phassus giganteus (100 d) in South America. The marks of the primitive habitus of the He¬ 
pialidae are both morphological and biological. The extremely slim shape similar to that of a dragon-fly, 
most obviously exhibited by the Phassus which are especially well developed in America, the mostly very 
feeble antennae and the absent palpi and oral parts, the strong shaggy legs, the peculiar position of the 
forewings and hindwings exhibiting an interstice, the hair on the wing-membrane, the more or less hair-like 
scales on the wings, the neuration being the same (12 veins) on all the four wings, the subterranean or 
endoxyle habits of the larvae which resemble the grubs of cockchafers (bare with tubercles and a hard shiny 
head and strong biting organs), the mobile pupa provided with limbs, the peculiar flying habits of many 
species resembling those of certain Ephemerids — all these peculiarities prove the Hepialidae to be one of 
the primitive types of lepidoptera. This is corroborated by the fact that most of the members of this family 
are to be found in the isolated Australian Region abounding in archaic forms. America is not only ab¬ 
solutely but also relatively poorer, since only about 90 species occur there, compared with more than 100 
Indo-Australian species. We must, moreover, consider the immense extent of the region and, besides, the 
enormous development of its lepidoptera, in order to be able to realize the difference of the two faunae com¬ 
pared; especially since, including the forms and synonyms, more than 15 000 names of American Rhopalocera 
have been dealt with in Vol. V (Gaede). 
Owing to the immense extent of the region covering tw r o continents, the Hepialidae show of course 
a very different exterior in the various parts of this range. The North-American (neoarctic) forms are closely 
related to the European and palaearctic ones in a restricted sense, belonging for instance to our ganna , hectus, 
velleda and carna groups. The habitus of the antarctic forms ( Pielus , Callipielus) approaches that of the 
South-Australian and Tasmanian species. Between the two subregions, in the tropical zone extending from 
Mexico to Paraguay, the Phassus and Dalaca are inserted, to which most of the American Hepialidae belong. 
Great numbers of other forms are yet to be expected from this region, since every expedition of collectors 
will probably yield new forms. 
The Hepialidae are very unequally distributed over America. In general, the mountainous districts of 
the w r est (Rocky Mts., Cordilleras) are much preferred. In North America, California abounds most in Hepia- 
lid species. From the Equator to the southern point of America, the number of species decreases remarkably; 
quite poor, however, is the subregion of the Antilles from where, as far as I know, not any Hepialid species 
has yet been brought. A peculiar fact which, however, is not unique (cf. Madagascar); still, no satisfactory 
explanation for it is known to me *). 
With the American Hepialidae we are still more confronted by the difficulty of a somewhat unbroken 
description than with the Indo-Australian ones. Especially the South-American forms, above all Dalaca, need 
sifting, since a lot of undescribed material, which is constantly increasing, sticks in the collections. Another 
difficulty is offered by the impossibility of obtaining authentic specimens. Nearly every family presumably 
contains descriptions that are based upon a single type. Yet this is most extensively the case with the He¬ 
pialidae, especially the American ones, more perhaps than with any other lepidopteral group. 
*) The cause may be that the Hepialidae are an old family and therefore to be found more in (the old) Australia, but 
hardly in the (volcanic) New Antilles (G-aede). 
VI 
162 
