2 October 2001 PROC. ENTOMOL. SOC. WASH. 103(4), 2001, pp. 777~787 DESCRIPTION, BIOLOGY, ANp KARYOTYPE OF A NEW PSILOCHALCIS KIEFFER (HYMENOPTERA: CHALCIDIDAE) FROM INDIANMEAL MOTH PUPAE (LEPIDOPTERA: PYRALIDAE) ASSOCIATED WITH CULLED FIGS J. A. JOHNSON, E. E. GRISSELL, V. E. GOKHMAN, AND K. A. VALERO (JAJ and KAV) Horticultural Crops Research Laboratory, 2021 S. Peach Ave., Fresno, CA93727, U.S.A.; (EEG) Systematic Entomology Laboratory, PSI, Agricultural Research Service, USDA, % National Museum of Natural History, Washington, DC 20560-0168, U.S.A.; ('YEG) Botanical Garden, Moscow State University, Moscow 119899, Russia Abstract.-Psilochalcis brevialata Grissell and Johnson, new species, is described and illustrated based on specimens from a laboratory culture reared on Plodia interpunc­ tella (Hubner) pupae. This species, isolated from laboratory-reared P. interpunctella placed at a culled fig warehouse in central California, is the first Psilochalcis associated with stored product pyralids. In the laboratory, P. brevialata also sucessfully parasitized Cadrafigulilella (Gregson), C. cautella (Walker), Ephestia elutella (Hubner) and Amyelois transitella (Walker). The karyotype of P. brevialata showed a haploid chromosome num­ ber (n) of 6, the highest n value known for the family Chalcididae. Female P. brevialata had relatively long reproductive lives of 39.3 days, producing an average of 3.3 progeny/ day for a total of 128.7 progeny per female. Key Words: Hymenoptera, Chalcididae, Psilochalcis brevialata, new species, Pyralidae, pupae A review of the hymenopterous parasites Psilochalcis (as Invreia), originally con­ of stored product insects (Gordh and Hart­ sidered an Old World genus, was first re­ man 1991) included only two cha1cidid spe­ ported in the New World based upon three cies: Antrocephalus aethiopicus Masi and species described from Oklahoma and Tex­ A. mahensis Masi, both parasitoids of Cor­ as (Grissell and Schauff 1981). A fourth cyra cephalonica (Stainton) (Lepidoptera: species from Arizona and Hawaii was add­ Pyralidae). No Psilochalcis species has pre­ ed later (Boucek 1984). Boucek (1992) re­ viously been recovered from stored product ported that less than 20 species of Psilo­ pyralids, and few host records are known chalcis were known from the western hemi­ for the genus (Boucek 1992). Grissell and sphere. Boucek and Halstead (1997) re­ Schauff (1981) summarized the then known cently stated that at least 10 undescribed hosts, which consisted of two pyralid spe­ species occurred in the Nearctic Region. cies in the Old World and a pyralid and gelechiid species in the New World. Naren­ As part of a project to integrate natural dran (1989) reported as a host a species of enemies into non-chemical control pro­ the family Oecophoridae from India. No bi­ grams for postharvest dried fruits and nuts, ological .observations have been made on a survey was made of the insects present at any species, but in the few reared instances, a culled fig warehouse in Fresno, California adult wasps emerged from the pupal stage (Johnson et al. 2000). Because culled, sub­ of its host moth. standard figs are judged unsuitable for hu- 778 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON man consumption, little or no attempt is was smeared on the underside of the lid. made to control pests within the warehouse. Dishes were held under rearing conditions Consequently, large pyralid populations de­ until emergence of adult Psilochalcis. velop in these figs, which in turn support These adults, along with any remaining in various parasitoid populations. During the the jars, were used to continue the culture. course of the survey, we discovered an un­ Specimens from several generations of the described species of Psilochalcis (Hyme­ laboratory colony were killed in 70% noptera: Chalcididae) parasitizing pupae of ETOH and sent to E. Grissell for taxonomic the Indianmeal moth, Plodia interpunctella study. (Hubner) (Lepidoptera: Pyralidae). In this Karyotype.-Parasitized hosts from the paper, we describe the new species Psilo­ laboratory culture were sent to V. Gokhman chalcis brevialata Grissell and Johnson and for karyotype determination. Chromosome include observations onits culture, biology preparations were obtained from cerebral and karyotype. ganglia of prepupae according to the tech­ nique of Imai et al. (1988). Chromosomes METHODS AND MATERIALS of three males and three females of P. brev­ Maintenance of laboratory culture.-We ialata were studied. For making chromo­ began a: laboratory culture of Psilochalcis some measurements, ten haploid metaphase using material reared from traps baited with plates were scanned directly from the prep­ host pupae placed at the culled fig ware­ arations using an optic microscope fitted house in November 1994 and June 1995 with a static TV camera connected to a per­ (Johnson et al. 2000). Host pupae were sonal computer equipped with the image from a laboratory culture of Indianmeal analysis program Imagefixpertv version moth reared in glass jars (41) with about 1.0. Scanned images were measured using 350 g of wheat bran diet (Tebbets et al. Adobe Photoshop'" version 3.0.5. Statistical 1978). Corrugated cardboard strips (2.5 em analysis was performed with the help of X 2 m) were placed on the diet surface, STATISTICA® version 4.3. coiled along the inner wall of the jar, to Life history.-We obtained adult Psilo­ serve as pupation sites for Indianmeal moth chalcis of known age by placing individual larvae. Strips with 1-3 day old pupae were parasitized host pupae in glass culture tubes transferred to clean jars, along with a hand­ (12 X 75 mm) closed with foam plugs. ful of diet containing mature larvae. About 1 g of honey was smeared along the inside Within 24 hours of emergence, adult para­ wall of the jar before adding 50-100 adult sitoids were removed from the culture tubes Psilochalcis. and sexed. Single pairs of male and female Psilochalcis rearing jars were kept in en­ wasps were placed in plastic Petri dishes vironmental chambers at 27°C, 60% RH, (90 X 15 mm) lined with filter paper. A and a photoperiod of 14:10 (L: D) h. Moths small amount of honey was smeared on the from unparasitized hosts were removed as underside of each lid. Only pairs that were quickly as possible, but not before some observed in copulo were used in the study. were able to lay eggs. Because these eggs A total of 15 pairs were used. Ten 1- to 4­ produced larvae capable of feeding on par­ day old Indianmeal moth pupae in cocoons asitized host pupae, 1 week after the addi­ were added to each dish. After 24 hrs, pu­ tion of adult Psilochalcis, pupae were re­ pae were removed, placed in plastic sample moved from the pupation strips and exam­ cups (30 ml), and held at noc, 60% RH, ined for evidence of parasitization (mela­ and a photoperiod of 14:10 (L:D) h for nized spots). Parasitized pupae were placed emergence of either moths or Psilochalcis. in plastic Petri dishes (90 X 15 mm) lined Host pupae were provided each day to each with filter paper. A small amount of honey Psilochalcis pair until the death of the fe- VOLUME 103, NUMBER 4 779 male. A similar test with 10 virgin females ameter (an area covered with effaced sculp­ also was done. ture); flagellum (Fig. 2) filiform, scape wid­ Potential host range.-Pupae from labo­ est in basal %, pedicel 2 to 3X longer than ratory cultures of various postharvest Lep­ any funicular segment, slightly shorter than idoptera other than P. interpunctella were clava, which appears to be one-segmented offered to recently emerged and mated Psil­ (ratio in holotype beginning with scape 55: ochalcis females held in plastic sample 18:7:8:9:9:9:9:9:9:21); scape ca. 1.3X as cups. After 24-72 hours, the pupae were long as eye height; pedicel 3 X longer than removed and held at rearing conditions for greatest width (apical). Mesosoma: Ratio emergence of either moths or Psilochalcis. pronotum : mesoscutum : scutellum: propo­ A total of five pyralid species (Lepidoptera: deum ca. 3:4:4:3 (holotype same); prono­ Pyralidae) were tested: Cadra figulilella tum, scutum, and scutellum with evenly (Gregson), C. cautella (Walker), Ephestia spaced, nearly contiguous setigerous punc­ elutella (Hubner), Amyelois transitella tures except punctures on median area of (Walker) and Galleria mellonella (Linnae­ scutellum vary from nearly contiguous (as us). We also tested pupae of the codling for male, Fig. 4) to 1 to 2 diameters apart moth, Cydia pomonella (Linnaeus) (Lepi­ (Fig. 5), seta length 1 to 2X puncture di­ doptera: Tortricidae). ameters; interspaces reticulate-aciculate; midlobe of mesoscutum with punctures ca. RESULTS AND DISCUSSION ~ own diameter apart (especially posteri­ orly); scutellum medially with punctures Psilochalcis brevialata Grissell and less than own diameter apart (as in Fig. 5); Johnson, new species mesepisternum with forecoxal depression (Figs. 1-7) not prolonged into flange ventrally; propo­ Description.-Female length 3.0 to 4.0 deum (Fig. 6) with complete well-devel-· mm (holotype 3.5 mm). Ratio head: meso­ oped submedian carina, prespiracular sulcus soma: metasoma: forewing ca. 1.5:5:5:6 carinate laterally, an irregular diagonal ca­ (holotype 7:23:25:29). Black except the fol­ rina joined from anterior of sublateral ca­ lowing yellow to dark reddish brown: te­ rina to inner posterior carina of prespira­ gula, tarsi, tibiae (except sometimes pro­ cular sulcus, with many transverse carinae and mesotibiae basally brown to black), between main longitudinal carinae; midfe­ metafemur at apex and base, metatrochan­ mur distally swollen, rounded ventrally, 3X ter, scape and flagellum (basal half of scape wider distally than proximally; forewing 2­ and apex of pedicel may be yellow). Head: 3X as long as wide (holotype 8:3), hyaline, Face (Fig. I) wider than high (holotype 5: ratio submarginal: marginal: stigmal veins 4), eye (Fig.