Certain Biological Relationships Between the Parasite Exorista Mella, and Its Host Estigmene Acrea
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Certain biological relationships between the parasite Exorista mella, and its host Estigmene acrea Item Type text; Thesis-Reproduction (electronic) Authors Adam, David Stuart, 1939- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 03/10/2021 20:54:33 Link to Item http://hdl.handle.net/10150/318219 CERTAIN BIOLOGICAL RELATIONSHIPS BETWEEN THE PARASITE EXORISTA MELLA, AND ITS HOST ESTIGMENE ACREA by • David So Adam A Thesis Submitted to the Faculty of the DEPARTMENT OF ENTOMOLOGY In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 1968 STATEMENT BY AUTHOR This thesis has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the Interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED I APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: J. A4% / T. F. WATSON ^<y Daten o Assoc. Professor of Entomology ACKNOWLEDGMENTS My sincere gratitude is extended to my advisor and thesis director, Dr, T. F. Watson, for his encouragement and advice throughout this study, I am greatly indebted to Dr, L, A, Carruth and Dr, G, W, Ware for reviewing the manuscript and serving on my graduate committee. ' Special appreciation is expressed to Paul Johnson for his assistance in the laboratory. 1 also wish to acknowledge the assistance of Jeffrey Slosser, Gerald Jubb, Jerry Phillip, and Robert Rush. ill TABLE OF CONTENTS Page LIST OF TABLES oeeoeooooeooeeeooeooooe.oeeoeeo ABSTRACT eeeeeedeeoeooeeeeoeeoeoftoeeoeeeoeeoeo "V11 INTRODUCTION« .... 1 MATERIALS AND METHODS4 RESULTS AND DISCUSSION. ................. 14 Adult Biology of Exorista me11a......... 14 Preoviposition Period.............. 14 Oviposition Period.. 15 Mating Suooess.....o..15 ^ Sex Ratio............oBee.ooooo.oe. ly Feoundity............e.o........... iy Longevity @o.....e.oee..eoo........ 22 Size..........e.oe................. 22 Oviposition Behavior............... 24 Developmental Times of Egg, Larval, and Pupal Stages of Exorista me11a ....... 27 Success and Efficiency of Parasitism Relative to Host Stage .e............. 33 Success and Efficiency of Parasitism Relative to Host Size................. 39 Supe rparas i t ism..,..........,@... 0 8 .0 0 .. 48 SUMMARY...e...... 0 9 .o.O............0 .0 ......6 52 REFERENCES CITED o........... 6...... 53 iv LIST OF TABLES Table page le Distribution by weight of later ins tars of Estlgmene acrea ........... 11 2 o Relationship of adult age to mating success of Exorista me11a 0 0 0 0 0 6 16 3® Relationship of the weight of Estlgmene acrea to the sex of Exorista Hie JL JL8, 0 0 0 0 0 0 &O@ & 66 9 09 9 O06@ &06'0 0 0 9 0 0©®©18 Dry weight of Exorista me11a females in relation to total egg production „« 19 5® Adult longevity and egg production of Exorista me 11a in the laboratory »,<,<=<, 21 6e Effect of host weight and multiparasitism on length and dry weight of Exorista me11a adults ...... 23 ?. Time required for hatching of first Exorista me11a eggs on the host. Estlgmene acrea. at 75=2° + 1.6 F.... 28 8. Duration of larval development of Exorista me11a as affected by molting and survival of Estlgmene acrea ...... 30 9e Duration of combined egg and larval stages of Exorista mella in various sized Estlgmene acrea at 75=2 and 75 ® 7 Fo.ee.o. ................. .... 0 0 e ; 31 10d Stage of Estlgmene acrea at the time of larval Exorista mella emergence ... 34 v vi LIST OF TABLES— Continued Table • Page lie Success of the parasite Exorlsta me11a in relation to the stage of its host Estlgmene acrea ............. .................... , 6 , * 36 120 Mean cumulative daily weight loss of twelve Exorlsta me11a puparla at 75-2 F„* * 37 130 Relation of puparial weight of Exorlsta me11a to weight of larvae and prepupae of Estlgmene acrea 38 14. Relationship of multiple puparlum production of Exorlsta me11a to size and stage of Estlgmene acrea..................e 40 15® Relationship of Exorlsta me11a puparlum mortality and multiple adult emergence to size and stage of Estlgmene acrea ......... 41 16. Influence of host weight of Estlgmene acrea on success of the parasite where parasite entry was observed oo.o.ooooo.o............ 44 17® A comparison of Exorlsta me11a success as a parasite on Estlgmene acrea when oviposition alone was noted and when oviposition plus parasite entry were noted. 46 15. Effect of superparasitism in Estlgmene acrea by Exorlsta me11a where parasite entry was observed .............o.................. 3® ABSTRACT The adult biology of the tachinid fly, Exorlsta me11a (Walk,) was studied in the laboratory. Various aspects of the relationship of this parasite to the salt marsh caterpillar, Estlgmene acrea (Drury), were examined# The mean oviposition period of E, me11a females held at temperatures fluctuating between 72° and 78° F, was 24.8 days. The mean lifetime egg production was 150.6, but varied with female size, Longevity averaged 3800 days for females and 29.5 days for males. E. me11a eggs hatched in 48 to 192 hours at 75° F. Maggot developmental time averaged 6.4 days in those instances where the hosts did not molt after parasite entry. Where host molt took place, developmental time required an average of 12,9 days. At 75°» the mean developmental time in the pupal stage was 10.1 days. When parasite er^try was observed, prepupal and pupal hosts successfully produced parasites twice as often as large larval hosts. Parasites utilized host prepupae as a food source to a much greater extent than host larvae and multiple emergence was much greater from prepupal hosts, Parasite success and multiple parasite emergence were alsc directly related to increasing host siSse. INTRODUCTION Bxorlsta me11a (Walk.) is one of the more non-specific tachinid parasites of lepldopterous larvae0 Schaffner and Griswold (193*0 reared it from 25 host species in the northeastern United States„ Thompson (1944) reported this parasite from 29 hosts in 7 families, while Simpson (1957) listed 4l hosts in 10 families0 The extensive range of this fly has been noted by Coquillett (1897) and others. Simpson (1957) reported the occurrence of adult E. mella across the southern half of Arizona from April to November. Taylor (1952) described it as one of the two most important tachinid parasites of the salt marsh caterpillar, Estigmene acrea (Drury) in Arizona. Tachina (= Exorlsta) mella was described by Walker in 184-9 but many synonyms were subsequently applied as this fly was recovered from numerous hosts in North America, Thus Townsend (1908) referred to it as Tachina clislocampae after it was reared from Cllslocampa disstria. Lists of generic and specific synonyms are given by Coquillett (I897) and by Sabrosky and A m a u d (1965)0 The European species Exorlsta larvarum (Linn.) was introduced into New England Between 1906 and 19270 Burgess and Crossman (1929) believed the imported and native flies were distinct species, but Aldrich (1931) felt that the two were identical. Schaffner and Griswold referred to the native as E. me11a in 1934, but confusion persisted until the two flies were placed into distinct species by Sabrosky and Arnaud (1965), Since the taxonomy of this parasite is no longer considered questionable the present study was undertaken in the laboratory to clarify the Intricate host-parasite relationship between Estlgmene acrea and E. mella. This was considered as a prerequisite for more complex studies involving this host and parasite! Phases of adult £. mella biology studied included preoviposition and ovipositlon periods, mating success, sex ratio, fecundity, longevity, size, and ovipositlon behavior. Developmental times of egg, larval, and piipal stages of the parasite were recorded. The success and efficiency of parasitism was measured by several criteria. The host stage when para sitized was related to percent parasitism success, as well as to multiple parasite emergence; The puparium-to-host weight ratio was used to measure parasite food utilization in larval and prepupal hosts. Host weight at parasite entry was related to percent parasitism success, percent puparial mortality, multiple parasite emergence, and parasite sizee A comparison was made of the difference in parasitism success between hosts where parasite entry was noted and where oviposition alone was noted. Superparasitism was delated to parasite size, parasite Utilization of f6b& and percent parasitism success ® MATERIALS AND METHODS Larvae of the salt marsh caterpillar, Estlgmene acrea (Drury), used In this research were descendants of individuals collected in or near cotton fields in September 1966 and July 1967, near Coolidge, Arizona, Most of the Exorlsta me11a (Walk,) used were descended