Louisiana State University LSU Digital Commons LSU Agricultural Experiment Station Reports LSU AgCenter 1981 Biology and illustrated key for the identification of twenty species of economically important noctuid pests A D. Oliver Follow this and additional works at: http://digitalcommons.lsu.edu/agexp Recommended Citation Oliver, A D., "Biology and illustrated key for the identification of twenty species of economically important noctuid pests" (1981). LSU Agricultural Experiment Station Reports. 260. http://digitalcommons.lsu.edu/agexp/260 This Article is brought to you for free and open access by the LSU AgCenter at LSU Digital Commons. It has been accepted for inclusion in LSU Agricultural Experiment Station Reports by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. Biology and Illustrated Key for the Identification of Twenty Species of bconomically Impor tant Noctuid Pests A.D. C liver and J. B Chapin LOUISIANA STATE UNIVERSITY AND AGRICULTURAL AND MECHANICAL COLLEGE Center for Agricultural Sciences And Rural Dei lopment ALVIN C HARPER CHANCE. LOP AGRICULTURAL EXPERIMENT Sia;ION DO^E C-1 AMBERS, DIRECT "P Table of Contents Page Introduction 3 4 Identifying Noccuid Larvae The Larval Key 6 Dichotomous Ke\ to the Larvae of 20 Species of Important Noctuid Pests Identifying Noctuid Adults 9 Summary Descriptions, Distributions, Hosts, and Seasonal Histories 9 Varieeated Cutworm, Peridroma saucia (Hiibner) 9 Granulate Cutworm, Feltia subterranea (F.) 10 () Dingy Cutworm, Feltia ducens Walker ' Black Cutworm. Agrotis ipsilon (Hufnagel) 10 Claybacked Cutworm, Agrotis gladiaria Morrison 11 Palesided Cutworm, Agrotis malefida Guene'e 11 Tobacco Budworm, Heliothis virescens (F.) 1- Cotton Boll worm, Heliothis zea (Boddie) '2 Cotton Leafworm, Alabama argillacea (Hiibner) .... 13 Green Cloverworm, Plathypena scabra (F.) 13 Velvetbean Caterpillar, A nticarsia gemmatalis Hiibner 13 A Giassworm. inicla infecta (Ochsenheimer) 14 Armyworm. P udaletia unipuncta (Haworth) • '4 Fall Armyworm, Spodoptera frugiperda (J. E. Smith) Beet Armyworm Spodoptera exigua (Hubner) I Southern Armyworm, Spodoptera eridaniu (Cramer) 15 An Armyworm. Spodoptera sutua (Guenee) l f Yellowstriped \t my worm. Spodoptera ornithogalli (Guenee) 16 An Armyworm, Spodoptera latifascia (Walker) 17 An Armvworm. Spodoptera doliehos (F.) 17 Color Plates 19 Glossary of Terms 24 Bibliography . 26 Acknowledgments The authors thank Gerald Lenhard for the photography; Michelle Schlueter and Pat MacLeod for illustrations; and Dr. B. H. Wilson. Dr. L. D. Newsom. and Dr. J. B. Graves for reviewing the manuscript Biology and Illustrated Key for the Identification Noctuid Pests of Twenty Species of Economically Important 1 A. D. Oliver and J. B. Chapin Introduction plates lor This bulletin contains keys, figures, and species of noctuid cater- use in the identification of 20 Louisiana agricul- pillars and moths of importance to is the elon- ture. According to Webster, a caterpillar noctuid gated, wormlike larva of a butterfly or moth. A moths in caterpillar therefore, is the wormlike larva of the fa.mil) Noctuidae 3 order Lepidop- o Noctuidae is the largest family in the U species or about 30 tera, consisting oi 2.500 to 2,800 * 5 Most percent ol the Lepidoptera in North America. Typical species are nocturnal, that is. active at night. The noctuid moths have a wingspan of 25 to 50 mm. States is the largest noctuid moth reported in the United ot black witch, Evehus odom (L.), with a wingspan smallest have a wingspread of about 1 2 cm. Some o! the '' are 25 to 50 mm long. PROLEG J^yf^S 17 to 17 mm. Typical larvae CROCHETS Manx of the most serious insect pests in the world belongto this family. Often referred to as worms, e.g.. ' used to place a larva in the fami 1 :utworms, armyworms, leafworms, earworms, and Fig. l. —Characteristics Noctuidae. budworms, the larvae are annual pests of many crops A .—Prothoracic segment with bisetose prespiracu'ar tubercle. rown in Louisiana. seta be- B. Abdominal segment with primarj setae onl\: 4 instars (stages) through 6 or 7 i These larvae develop hind and seta 5 below the spiracle. Proleg crochets are optimum oxer a period of about 30 to 50 days under uniordinal, uniserial, longitudinal mesoseries. conditions. The time interval between any two instars is is referred to as a stadium. When a caterpillar molts, it each other so developmental period or Because many species resembie I ) i the next instar stage and at times to make pror the last 2 or 3 closely, it will be difficult stadium It is during the development of habitat are not injury identification especially if host and nstars that most food is consumed and crop cannot be too careful in ascertaining the occurs. known. One and exact location where a caterpillar was Because of the importance ot noctuid caterpillars as time of year part ot the host fed as an its host, the growth stage and crop pest- in Louisiana, this bulletin was prepared found, the type of injury caused such as defoliation, aid to entomological consultants, farmers, and exten- upon, and boring, etc. Some species are single- sion agents in making proper identification ot 20 stem or hud others have two or more broods a year. Some species ol caterpillars which are responsible for much brooded: migrate north- the key should species are native to Louisiana; others f the crop injur} in the state. Users of more southern areas and usually do not become familiar with the external anatomy of caterpil- ward from before attempting to overwinter here. lars (Fie. 1 A-B: Fig. 2 A-E) monitoring an insect population in the field, identify them. Use of all figures and plates as indicated When collects Several species (kinds) oi worms in the ke\ to species will aid material!) in making one often be be difficult to distinguish. Some max correct identifications. which max LSI' Baton Rouge. La 70803 Professor and Associate Professor, respectively. Department of Entomology. uted to genetics, host species, season of year, popula- tion density, and length of time since the last molt Color characteristics aid in identification but must bo- used with caution. Because of the remarkable similarities in anatomical characteristics of caterpillars, some people do not at- tempt to make an identification. It must be realized thai the small degree of variation in structures can be use;! B effectively in determining the species on hand Identifying Noctuid Larvae A larva must be placed in the correct family before species identification can be made The typical noctuid C caterpillar body is without numerous secondary setae but has primal) setae which are located in definite patterns or locations. It has more than one pair ot abdominal prolegs. There are two setae in the Kappa group (prespiracular) on the prothorax in most species, but some exceptions exist such as the cotton leal worm which has one seta. The proleg-bearing segments have seta 4 behind and seta 5 below the spiracle on abdomi- nal segments 1-6. The proleg crochets are arranged uniserially, uniordinally, and in a longitudinal mesoseries. These family characteristics are shown in Figs. 1-5. The keys, figures, and illustrations in this paper are Fig. 2. —External anatomy of a noctuid caterpillar. of some common noctu . A. and B. \ Lateral view and B. dorsal view of typical cater- for use in the identification ot crops in pillar. DA, dorsal area; VA, ventral area; SUBD. A., subdor- caterpillars which are usual ly pests subventral sal area; SUP. A., supraspiracular area; SI BY. S., Louisiana. The information is not intended to include stripe. all species in the state but. instead, to provide brief C, Lateral view of caterpillar showing body segmentation; Tl, information on identification, hosts, season i! distor- prothorax; T2, mesothorax: T3, metathorax; PL1, first pair of each species listed. abdominal prolegs; PL2, second pair of abdominal prolegs; tion, and type of injur) caused by PL3. third pair of abdominal prolegs; PL4, fourth pair of Spodopteru sunia (Guene'e) does not occur in Louisiana dodominal prolegs; APL, anal pair of prolegs. at this time but was included in case incipient infesta- and E. Head capsules. SM.A., submedian arc; ADF.S., ad- D tions become established. frontal suture; RET. I)., reticulations, dark color; RET.L., re- Figures are not drawn to scale but are furnished • ticulations, light color; ADE.A., adfrontal area; NO RET., no structures and characteristic s reticulations. aids in finding anatomical used m making identifications. The keys and figures cannot be used to identify worms not listed in this paper. Very young larvae of most species cannot be ace lately identified with this or any other known key. I also must be realized that hosts, egg deposition char are good aids in important pests: o hers may he incidental and present teristics. season, and larval habits stage ot de no problem. Nee... for proper identification, therefore, making identification- ot larvae in any is a most important consideration in pest control. velopment. one Naturally, othei important factors which influence After using the key in making an identification, descr.p pest control decisions are life cycle, seasonal history, should refer to the brief sections on summary given for seasonal distribution, and resurgence potential. The tion, hosts, seasonal history, and distribution comm. less experienced entomologist will face these problems each species. Species without accepted descrip- often and may require advice from others. names are indicated by an asterisk (*) in the Post-embryonic (after egg hatch) pigmentation of tions which follow the larval key . A glossary of some and caterpil- the bod\ wall often varies among individuals in the common terms used in describing moths copulation of a species. This variation may be attrib lars is provided at the end of the paper. 4 VERT T ^ y EPS. 0 2 / 6 ADF S ©3 3 n J A C iP 0 4 Op 6 4 © 5 © 5 j 06 © 6 J d 6 VERT T.