Joiirnal of the Lepidopterist r' Societ y , .. .... ,' 1 _. .. .. 49;2i. 1995, 16:5-170 .I BIOLOGY OF URESIPI-IITA PiEj'ERSALIS (GUCX'ÉE) AKD COMPARISOS !VITH U. POL>~GOiYALZSNilORIALZS (FELDER) (CR AMBI DA E) ROSEN.IRYL EES Cnited States Departmeiit of Agriculture-Forest Ser\ ice Qiiarantine Facility, P.O. Bol 236, \'olcano, Ha\vaii 9675.5, LIS.\ ABSTRAC?'. The biology of Uresiphiia recersalis (Guenee) is described, and the uripublished thesis of hlulva). on Uresiphita polygorzalis maorialis (Felder) is summarized. The biologies of the t\vo species are identical in many regards. Eggs are cream colored and laid in overlapping clusters of up to SO. Larvae undergo five instars; they are brightly colored, gregarious, and aposeniatic. Pupae are dark brokvn. Overivintering usually occurs in the pupa1 stage. Adults are active nocturnally and are superficially similar, \vith dark brown foreuings and light orange hind\vings \vith br0u.n markings along the outer rnargin. In coritrast to larvae, adults of both species are suspected to be palatable to predators on the basis of their color, nocturna1 activity, and absence of sequestered cluinolizidine alkaloids in adults of U. recersnlis. Both species are multivoltine. Larvae of U. reversalis are diurnally active but feed throughout the night under \varrn temperatures. Additional key words: P!didae, Pyraiistinae, circadian acticity, geographic distri- bution, Genista. The genus Uresiphita Hübner is a sniall group in the family Cram- bidae (subfamily Pjmustinae), according to hlunroe's (1089) revised classification of tlie Pjnloidea. Tlie biology of only one species, Ure- siphitn polygorinlis mnoriali.s (Felder), has been studied in detail, and ' tlie resiilts of those stiidies are presented iri the iinpublished hlaster's thesis of hlul\.a). (19i8). Uresiphita polygonnlis mnorinlis, the kowhai nioth, is indigenous to Ken. Zealand and is a pest of introdiiced liipines (e.g., Lupincts nrborercs Sims; Fabaceae) (Ferro 1976). hlul\-ay (1978) studied the biologj. of this species in the contest of identif!.ing methods to inhibit daniage to liipines. hlul\.aj. (1978) concluded that LJ. p. mnor- inlis Lindergoes tu.0 or three geiierations per "ear on the Nortli Island of Nen. Zealand, and o\'ern.inters in tlie pupa1 stage. Laboratory studies oii the circadiari nct-i\.it!. of iiidi\~icliiallyisolnted males arid females re\wled tlint adiilts \\'cre nocturnall!. actiive n.hen esposed to alternating light and dark conditioiis or u.Iieii subjected to constant darkness. O\i- positioii \\.as primaril). 011 tlie lo\\.er siirfaces of Sophorn (Fabaceae) lea\,es but 011 tlie upper surfaces of Lupiniis lea\.es. Eggs 1iai.e a lacelike pattern on the chorion ancl are laid in o\,erlnpping clucters of ~ipto '75. h,Icil\,aj. (1978) described tlie 1m.ae of U. p. ninorinlis as crjrptically colored and suggested that the!. probabl!. do not use host plant alkaloids, biit presented no evidence to support this conclusion. Larvae are orange or green \vith conspicuous ).ello\\. and u.hite lateral lines, and have black tubercles, \i,hite patches, long n.hite hairs, and dorsal Lvhite spots; they 161 JOCRS-\L or' -IIIE LEPIDOPTERISTS'SOCIETY feed gregariously. Based on coloration and pattern, larvae of U. p. mnorialis appear to be aposematic. blulvay described larvae as cryp- tically colored probably because the). are obscured from vieu. on de- foliated stems v-hen thej. orient themselves along the length of the stem. The number of instars of U. p. innorialis Lm-ied \i.ith the host plant. Larvae reared on Sophota microphylla Ait., Ulex eiiropaeus L. (Fa- baceae), or Genista monspessrtlann (L.) L. Johnson (Fabaceae) under- lvent five or six instars. Larvae reared on Lupinus arboreus had five instars and smaller head capsules than those reared on S.microphylla. Larvae reared on Sophora hozoinsular (M7. R. B. Oliver) P. S. Green completed sis or sm'en instars. Pupation occurred on host plant leaves, beneath loose bark, or inside crevices of the stern. Pupation did not occur away from the host plants. Uresiphita reversalis (Guenée), the genista caterpillar, is the only niember of the genus known to occur in North America (Munroe 1976). Comstock and Dammers (1933) pro\& the earliest and most estensive descriptions of the egg, larvae, and pupae. Other descriptions of the early stages are provided ti).hícKenzie (1933) and Bernays and Montllor (1989). ?'he present paper reports tlic i-ejults of stuclics 011 the geographic distribution, life histor)., and circadiari activity of U. reversalis. Data \\rere gathered pritnarily in tlie laborator). 011 popdations originating f ron1 nortl-iern California. \\.'lien posible, field data \\rere gathered on populations in the San Francisco Ba). regioii of California, and these are noted in the test. DISTRIBVTIOS Distribution information on U. reversalis \vas obtained through a review of the literature and Inuseuni collections (see Leen 1992 for specific sources). Uresiyhita wrersalis is a Xorth American species \vith a latitudinal distribution froni Ko\.a Scotia, Canada, into parts of hles- ico. Speciniens have been collected from nearlj. al1 states in the U.S. except those surrounding and directl). u.est of the Great Lakes. Colo- rado, Nebraska, lo\\.a, and Illiiiois represent tlie northern liniits of dis- tribution in the mid\\-estern U.S. The \\.estern range estends to Arizona and California, including the California Channel Islands. I found no records of U. rcccr,saIi.s froni Ke\.ada or Utah althoiigh apparentl). acceptable host plants are present tliert.. The current distribution of U. r~~.t'rs(~Ii.sin central and northern California is attributed to a rarige espanrion that occur-red in the early 1950s (Pon.ell 1992). According to the California Departnient of Ag- riculture identification records, the distribution of U. reuersalis ex- tended northLvard during the 1980s. In 1980 and 1982, it \tras collected - in the northern interior county of Shasta. In 1990, the nioth \\.as collected 8 VOLUUE 49, hT~hi~~~2 165 at Fort Bragg in h4endocino County, the northernmost site recorded on the California coast. Freezing temperatures during December 1990 markedly decreased field populations throughout northern California, although U.reversalis was collected again in Mendocino County (Ukiah) in October 1991. The eastern limit of its distribution in California lies near the state boundary. Specimens have been collected from the foot- hills of Placer and San Bernardino counties. LIFE HISTORY The developmental rates of U. reversalis from egg through adult were observed in the laboratory at 20°C and 16L:8D. Adult longevity and egg productivity were studied under the same conditions. Eggs Observations of oviposition patterns and egg numbers were made in both the laboratory and the field. Eggs are shiny and yellow, and laid in clusters in an overlapping pattern resembling fish scales (Fig. 1). Cluster size ranged from 1 to 88 (2 = 19; n = 91) in the laboratory. Clusters observed in the field ranged from 3 to 65 (R = 39; n = 35). Egg clusters are laid on both the lower and upper surface of leaves. On Ccnista monspesszilana, 63% (50/79) of clusters observed in the laboratory and 68% (17/25) of clusters observed in the field were on the upper leaf surface. Additional field observations on other host plants also show surface placement is variable. Clusters were obser\.ed on the upper surface of L. arboreris 67% (4/6) of the time and on the upper siirface of Baptista lezicarztlia lorr. and Gray 25% (1/4) of the time. None of the laboratory or field values diff er significantly from 50% (z- test, p > 0.05).Field data \vere gathered from potted plants maintained in Albany, California. Larvae Egg incubation a\,eraged fi\re days (n = 50). Newly enierged larvae occasionall). cannibalized larvae that \vere slonrer to emerge. The cho- rion often v.as eaten after emergence, suggestirig that cannibalism is probably an indirect consequence of this feeding. The time required for development from larva1 (Fig. 2) to pupa1 stage when fed G. n20n- spessrclana \\.as 28 days (based on 217 lar\.ae from 29 separate clusters of eggs). Head capsule uridths \\.ere nieasured for 205 larvae reared on G. ~nonspesszilanain the laboratory. Larvae go through five instan with head capsule widths ranging from 0.18 to 0.36 mm for the first instar; 0.45 to 0.72 mm for the second; 0.81 to 1.17 mm for the third; 1.26 to 1.89 mm for the fourth; and 1.98 to 2.34 mm for the fifth. Larvae fed on the foliage aiid flonvers of the host and ate bark and other soft stem tissiies wlien foliage \vas not available. First instars initiall>r fed o11 the leaf surface (upper or under) iipon u-liich tlie eggs nrcre oviposited rather than exclusi\Fel), on the upper surface, as iniplied c b? Berna? s and hloritllor (1 9S9). Coloration has been described accu- ratel? b? se1 eral autliors (Chmstock 6 Dammers 1953, Berriaj.s ti Mon- tllor 19S9), arid Iieed riot be rcpeatecl here. Aspects of tht. aggiegative beliaxrior are discussecl iri Leen (1992). Pupae The pripae are dark bro\\.ii \\.ith aii a\.erage \\.eight nf 80 mg (n = 20) for niales and 92 nig (n = 49) for females (Fig. 8). De\.elopnient froni pupa to ridult n\.eraged 18 d;i?-s (ii = 21)..-\ solid. tliick c‘ocoon is fornied pi.ic)r to piipntion. \\ liicli occ-urs :i\t-a>’frnm tlie liost plaiit. i’upae \\.ere fouiid iiiider \\-ood at 2 and 10 111 frorri the host plaiit; larvae searched for pupatiori sites at e\pen greater distances (20 ni). l’upation occiirred on a host plant v-hen additional shelter (e.g., 5 ciii u.ide tape) \vas provided but did not otliermrise occur there. In the laboratory, lanrae cannibalized pupae, even n-lien liost plant foliage \\.as aldable.