The Lepidopterists' News
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The Lepidopterists' News THE MONTHLY NEWSLETTER OF THE LEPIDOPTERISTS' SOCIETY P. O. Box 104, Cambridge 38, Massachusetts, U. S. A. Editor - C. L. REMINGTON • Assoc. Editor - J. E. REMINGTON Volume II April 1948 Number 4 LEPIDOPTERA BIOLOGY -- OPEN FOR STUDY Biology is 11 terally the "science of life ". courtship, duration of coitus, time of day or In the present discussion it will be used in night of coitus,etc.), oviposition habits,and the strictest sense, to mean the study of larval feeding habits (whether diurnal orno~ LIVING Lepidoptera, as contrasted to the stu turnal, what part of plant eaten, defensive dy of dead collection specimens. A large pr0- actions, gregariousness, etc.). portion 0 f our Society members are not pro fessional entomologists, and it is these en (3) HABITAT. The precise location 0 f the thusiastic avocationists whose attention the ova, the larva (day and night), the pupa, and NEWS editors have endeavored continually to especially the adults. In all species we need direct toward the study of Lepidoptera IN THE to know just where the adults live. For ex FIELD. What are the aspects that a lepidop ample, Erebia theano ethela is restricted to terist can study methodically in whatever re small sphagnum bogs; ~. magdalena is in the gion he may live? There are seven primary same area, but frequents only the dry rock ones: (1) phenology; (2) habits; (3) habi tat; slides; ~. tyndarus callias, flying nearby,is (4) host plants in each region; (5) enemies; only on vegetated, less rocky spots; and~. (6) population composition; (7)over-wintering. ~odea is somewhat lower, usually in tall lush grass. The precise altitudinal distri (1) PHENOLOGY. The season-to-season trend bution is not well-known, and in mountainous in Lepidoptera occurrence can be expected to regions would make a profitable study. give valuable information for all biologists. Lepidoptera are especially useful as a tool (4) HOST PLANTS. Here is one of the most in the study of yearly patterns because they important and, surprisingly, least accurately are so well-known taxonomically and their ap known aspects of Lepidoptera biology. Many peal to non-professionals has resulted in a species feed on quite different plants in dif large number of widely-distributed active ferent regions. Euphydryas phaeton eats Che field workers. The only region well-known lone glabra in New England, but in Missouri phenologically is Great Britain and, to a the host is Aureolaria flava. The Lep. Soc. much lesser degree, western Europe. The an expects eventually to publish a list of known nual Season Summary of the Lep. Soc. is an host plants of North American butterflies(and effort to gather such information for North of other groups) as information is assembled. America, and we hope to expand it to include There is a ~lant identification service avai other parts of the world as organized cooper lable (see NEWS, vol.I: p.25). ation develops. Each collector can keep his own records and will find it interesting to (5) ENEMIES. It is especially important compare them year by year. Several Lep. Soc. that all parasites obtained in rearing Lepi members keep field notebooks and record the doptera be saved and complete data, including species taken or seen, their abundance, and the name of the host, kept with them. Insects, their condition after each collecting trip. birds, lizards, and other animals which prey Some of these lepidopterists try to get out on larvae or adults should be noted. at least once each week throughout the col lecting season, in order to have a continuous (6) POPULATION COMPOSITION. The mathema record. Unfortunately, most collectors fail tically inclined lepidopterist can assemble to keep a record of species which are not scientifically valuable data on the percent collected because of commonness. Phenologi ages of various forms in local populations of cal records need to be correlated with wea each species. In Catocala lacrymosa, what ther data. part of the population are the striking forms?; in Lycaena hypophleas, how frequent (2) HABITS. Very little is known of the are the aberrations?; in Papillo glaucus, special habits of different species, especi what percentage of the females are black? and ally as they differ from related species. Ac so on. curate observations are needed on the manner of flight, sociology (which species "chase" (7) OVER-WINTERING. In too few cases we others, which are gregarious, etcr), prefer know the life history stage -- ovum, larva, ences of food of adults (which flowers are pupa, or adult -- in which a species passes chosen, which species are attracted to damp the winter. But we especially need to know ness, to carrion, to dung, to sap flows,etc.), whether Hemiargus isola, Eurema mexicana, color preferences, the normal resting posi Agraulis vanillae, and others survive the tion (wings open or closed, head upward or winter in any stage in Colorado, Kansas, and downward), location of night resting for di Missouri. ~ urnal species and of day resting for noctur nal species, aspects of copulation (type of ~ C.L.R. Vol.II, no.4 PRINCIPLES OF TAXONOMY - II. DEFINITIONS OF TERMS Taxonomy was produced, perhaps partheno Several NEWS readers have requested that genetically, by Carl von Linne. For a long we give definitions of technical words com time it expanded as a rather shapeless mass, monly encountered in writings on Lepidoptera. or as a mass varying in shape from classifier The following apply to Lepidoptera and not to classifier. Each early worker acknowledged necessarily to any other group. the biblical premise that Diety had created all the species at once as outlined in Gene (1) Ovum. Usually used to refer to a fully sis, and each worker believed himself the au formed fertilized egg after oviposition. thor of a new filing system o£ species ar May also mean the unfertilized germ cell rangement, which was admittedly arbitrary. In in the ovary of the female. (Plural- ~.) the beginning of the 19th Century there began (2) Larva. The caterpillar, or grub, stage to appear in biological writings a hint that during which most growth and feeding oc species had undergone many changes, probably cur. Strictly used, this is the stage in response to the environment, and were not following emergence from the egg and pre placed on earth in complete and final form. ceding pupation in insects with complete This idea developed slowly until it took a metamorphosis. (Plural- larvae.) sudden leap to rational reality in the 1850's (3) Pupa. The "restingltstage between the through the brilliant work of Charles Darwin. larval and adult stages, during which the adult is formed. May be enclosed in a co Without himself being a taxonomist, Dar coon in some Lepidoptera, or naked. (Plu win took the varying mass of the body of tax ral- ~.) onomy and miraculously gave it a clear, true (4) Chrysalis. Usually the pupa of butter form by presenting it with a skeleton -- phy flies, only. (Plural- chrysalides.) logeny. The principle of organic evolution (5) lm£gQ. The adult, sexually mature stage, made possible what we call a Itnatural classi having functional wings in all but a few fication lt • The term Itphylogenylt is from the Lepidoptera. (Plural- imagines[preferred], Greek (phylon- a tribe, and genos- descent) or imag~; adjective- imaginal.) and refers to the ancestry, or family tree, (6) Ecdysis. Moulting (shedding) the skin. of organisms. The basic assumption is that (Plural- ecdyses; adjective- ecdysial.) all living entities, whether plant or animal, (7) Exuviae. The moulted skin of the larva. descended from one ancestor. Presumably this Never used in the singular. ancestor was very simple in structure and (8) Eclosion. Emergence of the imago from the gave rise to two main lines, the plants and pupal skin or of the larva from the ovum. animals, and these lines in turn subdivided (9) Instar. The period between two ecdyses. many times, giving us the multitude of differ The first instar is the stage following ent groups of plants and animals existing to emergence from the egg and preceding the day, as well as many now extinct. first ecdysis. The second instar is the The reason we call our system a Itnatural" stage between the first and second ecdy classification is that we believe it express ses. The last instar is between pupation es true ancestral relationships. For example, and the preceding ecdysiS. Parnassius is included in the same family (IO)Stadium. Essentially synonymous with in with Papilio because there is reason to be ~. (Plural- stadia.) lieve they both descended from the same an (ll)Oviposition. The process of laying eggs. cestor, an ancestor which Pieris, Melitaea,~ (12)Hibernation. The dormant state during ~, and others did not share. Similarly, which the insects live through seasonal all these 5 genera are included in one super low temperatures (winter) at a very low family because it is believed that they all de metabolic rate. scended from one progenitor which was not the (13)Aestivation. The dormant state during ancestor of Hesperia, Pyrgus, and Megathymus. which the insects live through seasonal high temperatures or excessive dryness (summer) at a very low metabolic rate. (14)Primaries. The fore (mesothoracic)wings. (15)Secondaries. The hind(metathoracic)wings. (lb)Genitalia. All the special structures at the posterior end of the abdomen directly concernl~d wi th copulation. (17)Sympatrlc. Species which are sympatric occur together, at least in the same 10- cali ty, if not in the same stage of life history,. (18 )Allopatric. Species which are allopatric occupy separate ranges. (19)Dichromatism (sexual, seasonal, etc.). The OCC1~rence of different coloration in a specios. For example, Papilio glaucus, with d aJ'k females in the South, has sexu ~ dicIu'gmatism; Zerene caesonia.