The text below is grayed out because it is not intended to be read. It is a necessarily imperfect OCR of the original and is only used by a search engine.
Journal of the Lepidopterists' Society 35(2), 1981, 132-136
AN OXALIS (OXALIDACEAE) FEEDING LARVA, GALGULA PARTITA (NOCTUIDAE)
George L. Godfrey
Section of Faunistic Surveys and Insect Identification, Illinois Natural History Survey, 172 Natural Resources Building, Champaign, Illinois 61820
ABSTRACT. The ultimate instar larva of Galgula partita Guenee (Lepidoptera: Noctuidae) is described and illustrated. The hostplant for the larva of G. partita is documented as Oxalis (Oxalidaceae) which apparently is an unique larva/plant association among North American Lepidoptera.
This paper presents the first description of the ultimate instar larva of Galgula partita Guenee (Noctuidae: Amphipyrinae) and the first substantiated, published report of the larva's host. The detailed larval account may in time help establish the phylogenetic position of Galgula Guenee, which has no obvious relative, according to Forbes (1954), and is represented only by partita in Canada and the U.S.A. (McDunnough, 1938).
The only known larval host of partita is Oxalis. This statement is based on McFarland's (1965) indication, on the information in the description that follows, and on unpublished information at the U.S. National Museum of Natural History. Records from the latter source show that Galgula partita larvae were collected on Oxalis in Clemson, South Carolina, 15 December 1956 and were intercepted by USDA Plant Quarantine officials at Nogales, Arizona, 4 December 1960 and 4 August 1962 (Weisman, pers. comm.).
Associations of lepidopterous larvae feeding on species of Oxalidaceae apparently are rare. This is intriguing because there are seven genera and approximately 800 species in this plant family (Robertson, 1975). The situation may be related to the high concentration of oxalate in these plants. Details of the plants' chemistry were summarized by Hegnauer (1969), but additional speculation regarding possible plant resistance, etc., is beyond the scope of this paper. Basic larval hostplant indices and bibliographies (e.g., Forbes, 1954; Kimball, 1965; Kingsolver & Sanderson, 1967; Godfrey, unpubl. computerized host catalog) do not list any North American larvae of Lepidoptera from the Oxalidaceae. To my knowledge the only other published account of a lepidopteran being associated with an oxalid is McFarland's (1979) rearing of a geometrid, Metallochlora militaris (Lucas), on Averrhoa carambola L. (introduced plant) in Australia.
All line drawings in the following illustrations were done to scale, and explanation of the abbreviations was published previously (Godfrey, 1972).
Volume 35, Number 2 133
FiGS. 1-2. Galgula partita: 1, dorsal view; 2, lateral view (photographs by J. G. Franclemont).
Galgula partita Guenee
General. Head: integument smooth; width 1.40-1.50 mm (x = 1.47). Total length 12-17 mm (x = 14.57). Body: integument smooth; distinctly swollen at first abdominal segment (Abl) (Fig. 1), abruptly tapering cephalad and slightly tapering caudad to Ab3; segments Ab4-7 of equal width, declivous from Ab8-Abl0 (Figs. 2, 9). All setae simple. Prolegs present on Ab3-6, 10; size increasing only slightly caudad on Ab3-6, those on AblO slightly smaller than on Ab6. Crochets mesoseric, uniordinal.
Head (Fig. 3). Postgenal sutures parallel to each other; length of epicranial suture 0.42-0.46 mm (x = 0.45); height of frons (apex to Fa's 0.44-0.50 mm (x = 0.46); distance Fl-Fl 0.28-0.34 mm (x = 0.30); AFa cephalad and AF2 caudad of apex of frons; Al-3 forming right to slightly obtuse angle at A2; Pl-Pl 0.70-0.81 mm (x = 0.73); P2-P2 0.84-0.91 mm (x = 0.87); PI insertion approximately midway between epicranial suture and L; L cephalad of juncture of adfrontal ecdysial lines; antennaria concave; Ocl-Oc2 0.03-0.04 mm (x = 0.03); Oc2-Oc3 0.02-0.03 mm (x = 0.03); Oc3-Oc4 0.03 mm (x = 0.03).
Mouthparts. Hypopharyngeal complex (Fig. 4): spinneret elongate, tubular, its apex and tip of Lp2 extending subequally, length about 4.0 times length of Lpsl; length of Lpsl about 6.0 times that of stipular seta, 2.2 of Lpl, 10.0 of Lps2, 0.38 of Lp2; distal and proximal regions rather continuous; distal and proximomedial regions void of spines; proximolateral region bearing short, thin spines distally and about 12 flat, stout, lateral spines. Mandible (Figs. 5, 6): two outer setae present, distant from each other;
134
Journal of the Lepidopterists' Society
Figs. 3-7. Galgula partita: 3, head capsule, frontal view; 4, hypopharyngeal complex, left lateral view; 5, left mandible, outer surface; 6, left mandible, oral surface; 7, dorsum of seventh abdominal segment. Scale lines equal 0.5 mm.
inner ridges two and three terminating about at tips of outer teeth; inner tooth present, prominent, flat, longer than wide, sometimes broken and represented only by basal scar; first outer tooth small; second outer tooth serrated on side opposite first tooth; third and fourth teeth prominent, acutely angular; fifth tooth reduced but angular; sixth tooth reduced, rounded.
Thorax. Segment Tl: SD1 & 2 setal insertions separated from edge of cervical shield (Fig. 8): interspace Dl-Dl about 0.78 XDl-XDl; D2-SD2 about 1.53 SD2-XD2; setae SD1 and L2 present; spiracle elliptical, peritreme uniformly narrow. T2 (Fig. 8): Dl-D2 about 1.0 D2-SD2; SD1 hairlike; coxal bases contiguous to narrowly separated; tarsal setae 1-3 slightly thickened, 4 merely setose; base of tarsal claw produced, rounded to obtusely angulate.
Abdomen. Segment AM: 2 SV setae. Ab2-6 with 3 SV setae, 1 on Ab 7 & 8. Dorsal and lateral chaetotaxy of Ab6-10 as in Fig. 9. Setae D2 set in white subdorsal lines on
Volume 35, Number 2
135
Figs. 8-9. Galgula partita: 8, dorsolateral chaetotaxy of prothoracic (Tl) and meso-thoracic (T2) segments; 9, dorsolateral chaetotaxy of abdominal segments (Ab6-10). Scale lines equal 0.5 mm.
Ab2-7 (Fig. 7). Ab9: SD1 semi-hairlike, weaker than and distant from Dl and D2. AblO: posterior margin of anal shield entire; dorsal surface of anal shield broadly convex; subanal setae merely setose, subequal to lateral setae of anal proleg. Height of spiracle on Ab7 0.08-0.11 mm (x = 0.09), on Ab8 0.12-0.15 mm (x = 0.13). Length of dorsal setae on Ab7 0.12-0.16 mm (x = 0.14).
Coloration (living material). Head (Fig. 3): contrastingly marked, coronal and ocellar stripes glossy black, remainder of head essentially white or yellowish white; gular regions tinged with pink. Body (Figs. 1, 2): ground color brown; dorsal and subdorsal areas of Tl-3 and subdorsal area of Abl-9 dark brown; subdorsal area on Abl-7 divided into dorsal and ventral stripes by thin, white line; dorsal area of Abl-9 tannish brown; lateral area white with strands of tannish brown, continuous to tip of anal proleg; ventral area with strands of dark brown underlaid by white flecks; middorsal and subdorsal lines white, prominent on dark brown cervical shield, diffuse to absent on T2-Ab2; middorsal line of Ab3-10 white, continuous, becoming more distinct caudad; subdorsal lines on corresponding segments white and continuous but thinner, less distinct; dorsal margin of lateral area white, passing beneath spiracles on Tl and Abl then curving sharply dorsad on Abl and ending at D2, resuming at normal level at posterior margin of Abl and continuing caudad, running under but touching spiracles on Ab2 & 3 and passing above spiracles on Ab4-8, bending sharply dorsad on Ab8 to SD1. Spiracles dark brown to black with black peritremes. Thoracic legs black.
Material examined. 4 specimens: Highlands, Macon Co., North Carolina, August-September 1958, J. G. Franclemont, Oxalis sp. (yellow) (Franclemont collection). 3 specimens: IL.: Cook Co., University of Illinois Chicago Circle Campus, 16 August 1979; host—Oxalis sp. in greenhouse; coll. Larry Sykora (Illinois Natural History Survey collection).
Acknowledgments
I thank Dr. John G. Franclemont (Cornell University), Mr. Larry Sykora (University of Illinois, Chicago Circle Campus), and Mr. Don L. Weisman (Systematic Entomology Laboratory, SEA, USDA) for their invaluable information and discussions regarding this study.
Literature Cited
Crumb, S. E. 1956. The larvae of the Phalaenidae. U.S. Dept. Agr. Tech. Bull. 1135. 356 pp.
136
Journal of the Lepidopterists' Society
Forbes, W. T. M. 1954. Lepidoptera of New York and neighboring states. Pt. 3.
Cornell Univ. Agr. Exp. Sta. Mem. 329. 433 pp. Godfrey, G. L. 1972. A review and reclassification of larvae of the subfamily Had-
eninae (Lepidoptera, Noctuidae) of America north of Mexico. U.S. Dept. Agr. Tech.
Bull. 1450. 265 pp. Hegnauer, R. 1969. Chemotaxonomie der Planzen. Band 5. Dicotyledoneae: Mag-
noliaceae-Quiinaceae. Basel & Stuttgart. 506 pp. Kimball, C. P. 1965. The Lepidoptera of Florida: an annotated checklist. Arthropods
of Florida and neighboring land areas. Vol. 1, 363 pp. Gainesville. Kingsolver, J. M. & M. W. Sanderson. 1967. A selected bibliography of insect-vascular plant associational studies. U.S. Dept. Agr., ARS 33-115. 33 pp. McDuNNOUGH, J. 1938. Check list of the Lepidoptera of Canada and the United States
of America. So. Calif. Acad. Sci. Mem. 1(1): 1-275. McFarland, N. 1965. The moths (Macroheterocera) of a chaparral plant association
in the Santa Monica Mountains of southern California. J. Res. Lep. 4: 43-74. --------- 1979. Annotated list of larval foodplant records for 280 species of Australian
moths. J. Lepid. Soc, 33(3) Suppl. 72 pp. ROBERTSON, K. R. 1975. The Oxalidaceae in the southeastern United States. J. Arnold
Arboretum 56: 223-239.