Egg morphology of Draconia rusina Druce from Honduras (Lepidoptera: Thyrididae)

3 Pages·1992·1.3 MB·

by  S Passoa

PROC. ENTOMOL. SOC. WASH.
94(4), 1992, pp. 556-558
EGG MORPHOLOGY OF DRACONIA RUSINA DRUCE FROM HONDURAS
(LEPIDOPTERA: THYRIDIDAE)
Steven Passoa and Bruce A. Steinly
(SP) USDA/APHIS/PPQ, 8995 East Main Street, Bldg. 3, rm. 109, Reynoldsburg, Ohio
43068; (BAS) Illinois Natural History Survey, Center for Economic Entomology, 607 East
Peabody Drive, Champaign, Illinois 61820.
Abstract. —The egg and some first instar morphological features ofDraconia rusina are
given based on specimens collected in Honduras. This is the first record ofD. rusina from
Honduras and the second illustration of a Neotropical thyridid egg.
Key Words: Draconia rusina, Thyrididae, egg, first instar, Honduras
The systematic position ofthe Thyrididae (parental female number 78, S. Passoa coll.)
is unclear. Munroe (1972) and Whalley using cheesecloth as an oviposition sub-
1976) tentatively united thyridids with oth- strate. They were either dried or preserved
(
er Pyraloidea. Common (1990) and Minet in 80% ethanol. After several years, a few
(1983) elevated this group to its own su- dried eggs were mounted on aluminum stubs
perfamily named Thyridoidea. Passoa with Elmer's glue and sputter coated twice
(1985) suggested pupal pilifers as a synapo- at different angles with gold-palladium for
morphy of Pyralidae, Hyblaeidae, Ptero- further study. These were examined with an
phoridae, and Thyrididae. Although the information Scientific instrument DS-130
presence ofpilifers is apomorphic (by virtue scanning electron microscope and photo-
of the outgroup comparison method where graphed with Polaroid type 55 positive/neg-
Monotrysia is a sister group to Ditrysia), ative film. Structural measurements, ex-
this character is homoplastic because pupal pressed in microns or millimeters, were
pilifers also occur in the unrelated Papili- made directly from the scale line on the
onoidea (Mosher 1916). Very little is known photographs after dividing by the magnifi-
about immature thyridids (Whalley 1976). cation. Egg terminology follows Downey and
Therefore, the egg and some first instar lar- Allyn(1981).
val characteristics ofDraconia rusina Druce The egg (Figs. 1-4) is cream-colored and
are described here to aid in comparing the subcylindrical with nearly parallel truncate
morphology ofpyraloid families for system- ends (length 1.29-1.34 mm, mean = 1.30
atic and identification purposes. mm, n = 4; width 0.61-0.68 mm, mean =
Draconia rusina is a large moth previ- 0.65 mm, n = 3). The chorion sculpturing
ously recorded from Guatemala, Panama is composed of approximately 21 ridges
and Venezuela (Gaede 1936). Several spec- parallel to the long axis of the egg (Fig. 1)
imens of D. rusina were collected in Co- that converge and terminate at the micro-
mayagua, Honduras (Department of Co- pylar shoulder (Fig. 3). Ridges across the
mayagua) at a blacklight during April, 979, long axis are usually straight and separated,
1
and again in March and May, 1980. Ap- although a few are crossed orbifurcate (Figs.
proximately 20 eggs were obtained in 1979 1, 2; inter-ridge distance 17.02-29.79 ^lm,
VOLUME 94, NUMBER 4 557
Figs. 1^. Egg ofDraconia rusina Druce. 1, lateral view (59 x). 2, chorion ridges ofthe egg (235 x ). 3, oblique
view of the micropyle (122x). 4, aeropyle apertures of chorion (580x). Scale lines marked in microns under
each figure.
mean = 22.33 nm, n = 10). Aeropyle ap- hexagonal pattern ofcells on the chorion of
ertures occur on the chorion ridges (Figs. 2, Dysodia ska Druce but did not include lon-
4) with one aperture per 21.28 to 28.40 ^m gitudinal ridges in her illustration. In con-
(mean = 24.0 1 nm, n = 55). These apertures trast, Thyris fenestrella (Scopoli) (Sarlet
(Fig. 4) are irregularly shaped, with a width 964), Aglaopus pyrrhata (Walker) (Com-
1
(opening parallel to the egg's long axis) of mon 1990) and Draconia rusina eggs all have
6.38-19.15 Mm (mean - 10.55 ^lxn. n = 12) chorionic ridges. All four genera {Aglaopus,
=
and a height of 10.34-20.69 iim (mean Draconia, Dysodia and Thyris) share a
15.17 /um. n = 5). Micropylar end (Fig. 3) rounded, truncate apex which may be a gen-
consists of a circular depression (diameter eral characteristic of thyridid eggs. Com-
= 180.3 /um, n = 1) with a central raised mon ( 1 990), Aniello ( 1 980) and Sarlet ( 1 964)
tubercle (diameter = 77.87 ^m, n = 1). mention that thyridids have upright eggs.
A
review of published thyridid egg de- The location of the micropyle in D. rusina
scriptions revealed some differences be- is consistent with this type of egg.
tween taxa. Aniello (1980) mentioned a Although our Draconia rusina eggs never
558 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
hatched, dissection revealed a fully devel- Literature Cited
oped larva within the egg shell. First instar
Aniello, A. 1980. Life history ofDv50^/a 5/ca (Lep-
larva ofZ). rusina have a short front, a bise- idoptera: Thyrididae) in Panama. Psyche 87: 121-
tose SV group and apparently only one L 130.
seta on the thoracic segments, uniordinal Common, I. F. B. 1990. Moths of Australia. E. J.
crochets in a circle, and long setae on the Brill, Netherlands. 535 pp.
anal shield. The latter character is shared Downey, J. C. and A. C. Allyn. 1981. Chorionic
sculpturing in eggs ofthe Lycaenidae. Part 1. Bul-
with mature Thyridopyralis larvae which letin ofthe Allyn Museum 61: 1-29.
also have long setae on the anal shield. An- Gaede, M. 1936. Thyrididae. In Seitz, A. (ed.). Ma-
iello (1980) stated the crochets offirst instar crolepidoptera ofthe World. American Bombyces
Dysodia sica larvae are in a biordinal circle, and Sphinges. A. Kemen, Stuttgart. 1327 pp.
but this arrangement was not found in Dra- Minet, J. 1983. E'tude morphologique et phylogene-
tique des organes tympaniques des Pyraloidea. I.
conia rusina. Generalite's et homologies (Lep. Glossata). An-
nales de la Societe Entomologique de France 19:
175-207.
Mosher, E. 1916. A classification ofthe Lepidoptera
based on characters of the pupa. Bulletin Illinois
Acknowledgments
State Laboratory ofNatural History 12: 1-159.
We thank the Center for Electron Mi- Munroe, E. 1972. Pyraloidea. Pyralidae (part). In
croscopy at the University of Illinois for Dominick, R. B., etal. (eds.). The Moths ofAmer-
ica North ofMexico. Fasicle 13.1A. E. W. Classey,
advice and use of facilities. The comments London. 134 pp.
of T. Harrison, Dr. M. Berenbaum (Uni- Passoa, S. 1985. Taxonomy ofthe larvae and pupae
versity of Illinois) and Dr. G. Godfrey (Il- ofeconomicallyimportant Pyralidaein Honduras.
linois Natural History Survey) on various M.S. thesis. University ofFlorida, Gainesville. 486
pp.
drafts of this manuscript were greatly ap-
Sarlet, L. 1964. Iconographie des oeufs de Lepidop-
preciated. J. Apperson helped with the fig- teres beiges (Rhopalocera-Heterocera). Deuxieme
ures. Dr. D. Habeck (University ofFlorida) partie. Heterocera: Bombycides-Sphingides. Me-
allowed us access to his larval collection. moiresde la Societe Royaled'EntomologiedeBel-
This study could not have been completed gique29: 1-172.
without the identification ofthe parental fe- Whalley, P. E. S. 1976. Tropical leafmoths. A mono-
graph ofthe subfamily Striglininae (Lepidoptera:
male by Dr. D. Ferguson (USDA, System-
Thyrididae). Bulletin of the British Museum of
atic Entomology Laboratory). Natural History. 194 pp.