~ f28 I~ 128 ~F5 1.0 I.i.i .~ III~~ 1.0 W III;; ~ IiiW I:.l I:.lIii IW 122. ~ W 10: Ii:. ~ 11.1 :r ~ .0 ~ ~ 2.0 .. ~ .. 1.1 .... 1.1 .... ~ -- 111111.8 111111.8 111111.25 111111.4 111111.6 111111.25 111111.4 111111.6 MICROCOPY RESOLUTION TEST CHART MICROCOPY RESOLUTION TEST CHART NATIONAL BURE4U 0' STANOAROS-1953-A NATIONAL BUREAU {If STANDAR05-1963-A Technical Bulletin No. 721 April 1940 Paradexodes epilachnae, a Tachinid Para­ site of the Mexican Be.an Beetle 1 By B. J. LANDIS, associate entolllologist, and K. F. HOWARD, senior entomologist, Division of Truck Crop and Garden I"'sect Investigations, Bureall of Entomology and Plant Quarantine 2 CONTENTS Page Page Introduction .••____________ ...._..... ______ ._ 1 Bionomics.•. ____ •____ ..____ •____________._••_ 21 Bosts of Paraderodes epi/achnae Al<lrich._.- __ 2 The adult. ______ .•____ • ___ • __________ •••_ 21 llyperparasites of Paraderodes <pilachnae __ •• _ i nabits of the first·instar larva._.____ ._.__ 2{ Attempts to introduce Parae/erodes epiluchllUe Habits of the second·instar larva._ •• ____ ._ 2{ into the United States •. _... "'_"" _. "'__ 9 Babits of the third·instar Inn· .. __________ • 25 l\[et'lods used in breeding the parasite.. II Elfects of the pnrasite on the host _••••• _. 25 Care of parasitized hosts .. _.. _._.•..... _.. 11 Predacious coccinelJids as lJOsts .• ___ •••._.• ___ 27 Description of Paracierodes epi/achaae. __ •. _... 11 l~xtenF of.breeding nnd liberation_ .• _._ .•_.___ 27 The adult.•... _. __ ., __ .. _.._•• _•.•..._._ 11 (oloDlzntlon._______ •__ .. __ •.••_.•_•.___ •._••, 2S Theegg_ •••...• _..•..•..• _.•__ •••.•.••. _. 12 Spread [rolIl pointso((·"loniznti~·n_._••_______ 2S ~~~ ~~~~rium-~::~=:===:::=:=:====:-=::== g ~~~~~~:~!_h_~~~r_~:~~_~:~~~e_~~~_~[.:~~_:e~~~_ ml ~eproductive systems._____ ..__ •____ ._.__ 19 en"""=t­ q IJ\"TRODUCTIOK «::::::.>­ ~ The :YJ/}.xican bean beetle (Epilachna mriv1!stis "Muls.) hilS been known from the South,vest for about 85 years and appears to have migrated from Mexico, where it is widely distributed.3 In 1918 it appeared in Alabama and spread l'ilpidly over the centralllnd eastern parts of the united States. Its insect parasites and predators, how­ ever, did not follow the belln beetle into the new territory, and few of the parasitic and predacious insects occurring in the lTnited States appear to be of value in the control of this insect.4 Therefore, after the chance discovery of a dipterous pllpariuill in a quantity of larvae of Epilachna varivestis collected near Mexico Oity in 1921 by H. F. Wickham, who was detailed to search for parasites of the beetle in :Mexico, il, considerable search was made, chiefly in :Mexico, for natural enemies of this insect. E. G. Smyth was f'ngaged by the Bureau of Entomology to conduct this search. In 1922 he found a tachinid parasite of the larval stages of the belln beetle abundant at Me)..-ico Oity and shipped several hundred parasitized hosts and puparia to the junior author at Birmingham, Ala. .Adults were I :oubmitted (or publication Jul;- 13. 1039. 'The autilors 8ro indebt"'l to AI\"ah l'ctrrson, o( th(, Ohio State Unh'crsity, and C. C. Plummcr. R. W. Brubaker, O. V. Johnson, J. W. _-I.pple, and otbers o[ the BurC'au o( Entomology and Plant Quarantine (or n$Sistance in handling and colonization work. All the drawings werc wade by the s,'nior Guthor. 3 LA~DlS. B. J .. and PI.Ull}fER, C. C. THE }fEXICA~ BE.\~ BEETLE I~ }lEXICO. Jour. Agr. Res. ro· 989-1001, ilJus. 1935. j HOW.\RD, X. F., and L.\~nrs, n. J. PAR.\fifTES A~D PJ'.ED.\TOM OF TilE lfEXICA~ BE.\~ BP,:ETLE IN TilE l:~ITEn STATES. 1:. S. Dept. "\gr. Cir. 418, 12 pp., illus. 193'i. 1iS25Q-40 .2 TECHNICAL BULLETIN 721, U. S. DEPT. OF AGRICULTURE reared and submitted to the late J.:M;. Aldrich, who recognized them as new and described the species in 1923 5 as Paradexodes epilachnae. In 1923 Smyth again collected and shipped parasitized hosts and puparia to Birmingham. As had been the case the previous veal', the parasite did not survive the winter or become established after liberation, and the proj(.ct was discoutinued. It was later thought thaI; a more intensive study of the parasite and its hosts in Mexico might yield sufficient knowledge to make its successful introduction into the United States possible. In 1929 and 1930 the senior anthor was detailed to make such a study, and the work was carried on at Mexico Oity. During the period 1931-36 the parusite was reared at Oolumbus, Ohio, by the authors. Some of the results of these studies are recorded herein. FIGURE 1.-Map of central Mexico showing the area in which Paradexodes epilachnae was collected. The parasite was found abundantly at Mexico Oity and its presence was als(l established within the area from Jalapa, Vera Oruz, west to Guadalajara, Jalisco, and south to Oaxaca, Oaxaca (fig. 1). HOSTS OF PARADEXODES EPILACHNAE ALDRICH The knO\vll hosts of Paradexodes epilachnae in Me:\.-ico are Epilachna varivestis Muls., E. mexican a :Nluls., E. dejecta Muls., E. obscurella Muls., and E. viTgata Muls. In 1923 Smyth reared puparia, apparently of P. ep'ilachnae, from larvae of E. dejecta Muls. which he collected o.t Quetzal, Guatemala. The squash beetle (E. borealis (F.) was found to be a suitable host under insectary eonditions at Oolumbus. It is assumed that E. borealis and perhaps other epilaclmids not observed in Mexico are hosts of this parasite. , ALDRICH, J. j\-I. A NEW FARASITIC FLY :IRED FRO)! THE BEAN REETLE. Eot. Soc. "'ash. Proc. 25: 95-97. 1923. PARADEXODES EPILAORNAE, PARASITE OF BEAN BEETLE 3 FIGURE 2.-Epila.chna FIGURE 3.-Epilachna mexicana: Adult, varivestis: Adult, X 5. X 5. FIGURE 4.-Epilachna dejecta: Adult, " FIG U R E 5.-EpilachnCL X 5. obscurella: Adult, X 5. FIGURE 6.-Epilachna borealis: Adult, X 5. 4 TECHNICAL BULLETIN 721, U. S. DEPT. OF AGRICULTURE Epilachna t'ari'vestis (fig. 2) feeds on cultivated and wild beans (Phaseol1ls spp.), beggarweed (j1leibom1a spp.), and ocrnsionnllv other legumes. At :Mexico City, where there is one generation a y~a~, larvne are present from the btter part of June until some time in October (fig. 7). In more tropical Itreas of Mexico two or more genet·­ ations of E. 'l:arivestis OCCl:i.', but the period during which lal'vne are present is nearly the same. Epilachna me.i:icana (fig. 3) feeds on Oestrum aurantiaC1tm, O. 1l0cturn1lm, Echinocystus sp., Sicyos laciniata, Solanum bicolor, S. nig;'wn, and probably O. lanat1lm. 6 The ndult is 8.5 mm. in length. The lnrntl, pupal, and adult stages arc black, except for 12 large yellow or brick-red spots on the elytm of the ndult. Large numbers of eggs nre laid in elongate mnsses on the midribs of the undersides of leayes, At Cuernavnca, 1;101'elos, where there are two genemtions It year, adults were found on foliage along the banks of stremns froIll June 2 until October. 1;1nture IfLl'vne of the first generation were most abundant July 20. Adults were collected at Puente de Ixtla, ~rorelos, June 11 and July 25; at Xochimilco, Fedeml District, June 28; at Tnxco, Guerrero, July 10; nt Onxncn, Onxaca, August 22; and at )'lexico City. Federal District, August 29. Epilachna dt}ectQ (fig. 4) feeds on Oestrum aurantiacum, C. lanatum, C. noctllrmlln, Solanum bico[ol', nnd S. nigrum.7 The adult is 8.5 mm. jJ1 length. The ]egtl, \'ell trflJ sclerites, and mouth pfl.rts 111'e dun orange, find 10 large brick-red spots occur on the black elylril. Two egg maE'ses along the midrib on the underside of leayes contained 82 and 89 eggs, respectively. The larvae and pupae are black. Lal'\-ae and adults were present at JnJttpa and Cordoba, Vorll Cl'm:, on .June 7 and July 2, respectively; adults were present at Gua(\abtjam, Jalisco, on August 8. EpilachnCL obscyrella (fig. 5) feeds on beans, squash, and wild Cllcur­ bits. The adult is 6.3 mIll. in length, is bltlCk, and con'red with a gmv-green pilosit:r, except for 14 or fewer small spots on the dytl'i1. The lfil'Yae nre black, except immediately after molting, ·when the spines are white to the tips. The pupae are gray with blflcl~ stripes or patches fend resemble pupae of E. mrivestis l'etLl'ecl at low tempern­ ture. This species is less prolific. than /!.,J)ilachna varirestfs. Lan-ae letwing the egg mass scittter so tlutt two or more IfllTtle mrely are found feeding on the same Ienf. On squash th(' adults feed at the margins of the leaves si;niitll'ly to E. borealis, but areas are not "ringed" and wilted prior to feeding. Adults and lnrvflC were found at Chalco nnd XochimiLco, Federul District, Hnd n,t Cun,utla, ~rorelos, from ,Tune 11 through September, where they were associated with Epilachna writ'estis in mixed plantings of COl'll, beans, and squash, Epilaclma borealis (fig. 6) feeds on wild and cultivnted ('UGurbits, The ndult is 8 mm. in length. The larval tlnd pupal stnges closely resemble those of E. varicestis. The ndults differ in that E'. borealis hns 14 mther large blnck spots on the elytm nnel E. val'in~t is hns 16 mthcr SInILU black spots on til(' elytm. Adults wel'(' collected n.t Puente ele IxtIn, ).torelos, ;rune 11 and J tlly 2-:10; nt VNn ('I'lI"- and Cordoba, VerH Cwz, June 5 find ,Tuly 3, respectin>ly, nnd at GUlldnln­ jlll'tl, JaLisco, August 8.