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In oxygen-deficient waters, the difficulties of oxygen uptake in gill parasites and their fish hosts may influence host and parasite densities, site selection by the parasite, and effects of the parasite on host condition. This study quantified the prevalence and intensity of the gill monogenean Neodiplozoon polycotyleus in the African cyprinid fish Barbus neumayeri from an intermittent forest stream in western Uganda. Oxygen levels were low in the stream over the 12-month study, averaging only 2.5 mg litre−1 (monthly range = 1.2–4.3 mg litre−1). However, parasite prevalence was high (47.2%), suggesting high tolerance to low oxygen in N. polycotyleus. The prevalence of parasites varied with host body size, with the highest frequency of occurrence in the middle size classes. Prevalence also varied over the year; seasonal peaks of rainfall coincided with a lower frequency of N. polycotyleus. The significantly nonrandom frequency distribution of parasites among hosts suggests regulation of parasite numbers. Of the hosts infected, 37.1% harboured one N. polycotyleus parasite, and 62.9% harboured two parasites. No fish were infected with more than two diplozoons. There was evidence for strong site specificity by N. polycotyleus within hosts; 77.7% of the parasites were located on the filaments of the second gill arch, which may relate to increased oxygen availability. In addition, only one of the 178 infected fish had more than one parasite on one side of the branchial basket. Although N. polycotyleus is undoubtedly parasitic, we found no evidence of a negative parasitic effect on the condition or reproductive status of B. neumayeri. Resume Dans les eaux deficientes en oxygene, la difficulte que rencontrent les parasites des branchies et leurs poissons hotes peut influencer la densite des hotes et des parasites, la selection du site par le parasite et l'effet du parasite sur la condition de son hote. Cette etude quantifie la prevalence et l'intensitede Neodiplozoon polycotyleus chez le cyprinide africain Barbus neumayeri dans un cours d'eau forestier intermittent a l'ouest de l'Ouganda. Le taux d'oxygene du cours d'eau est reste bas pendant les douze mois qu'a dure l'etude, egal en moyenne a 2,5 mg/litre (ecart mensuel = 1,2–4,3 mg/litre). Cependant, la presence parasitaire etait elevee (47,2%), ce qui suggere chez N. polycotyleus une tres bonne tolerance a de faibles taux d'oxygene. La presence de parasites variait avec la taille, elle etait la plus elevee dans les classes de taille moyenne. Cette presence variait aussi au cours de l'annee, et les pics saisonniers des pluies corespondaient a une abondance moindre de N. polycotyleus. La distribution de frequence des parasites qui n'est significativemement pas laissee au hasard chez les hotes suggere une regulation du nombre de parasites. Chez les hotes infestes, 37,1% abritaient un parasite et 62,9% en abritaient deux. Aucun hote n'en avait plus de deux. On a constate l'evidence d'une forte specificite de site de N. polycotyleus chez les hotes: 77,7% des parasites se trouvaient sur les filaments de la deuxieme branchie, ce qui peut avoir un rapport avec une meilleure disponibilite en oxygene. De plus, seul un des 178 poissons infestes avait plus d'un parasite d'un meme cote. Bien que N. polycotyleus soit indubitablement un parasite, nous n'avons trouve aucune preuve d'un effet negatif sur la condition ou sur le statut reproducteur de B. neumayeri.

Differences in amount of pigmentation were observed in individuals of Simocephaluesx exspinosus, Simocephalus serrulatus, and Simocephalus vetulus collected from water bodies with or without visually oriented fish. In each species, individuals from permanent waters with fish were more pigmented than were individuals from temporary waters without fish. Pigmentation may reduce the ability of visually oriented predators to detect these crustaceans against structures in benthic habitats.

Studies on species of Monogenea have shown that these parasites often infect only a specific host species, genus, or family, and that they attach only to specific sites within hosts. Few studies, however, examine habitat specificity across host and habitat scales. In this study, we focused on host, macrohabitat, and microhabitat specificity in the monogenean diplozoon Afrodiplozoon polycotyleus, a gill parasite of African cyprinid fishes, Barbus spp. We first compared the occurrence of A. polycotyleus among 4 species of Barbus from a single location in the Mpanga River of western Uganda; Barbus neumayeri was the only species infected with the parasite. We then quantified parasite prevalence and mean abundance in B. neumayeri from a series of river and swamp sites in the same drainage, looking for environmental predictors of diplozoon prevalence and abundance over a broad habitat scale. The prevalence and mean abundance of A. polycotyleus on gills of B. neumayeri was highest in the hypoxic swamp habitat, followed by the intermittent stream sites, and faster flowing river sites. Parasite prevalence and mean abundance across habitats were negatively related to both water current and dissolved oxygen concentration. Within hosts, A. polycotyleus was strongly specific among hemibranchs in poorly oxygenated water and was found on arch 2, hemibranch 4 most frequently.

1. 1. Weight-adjusted metabolic rates of laboratory-reared, female descendents of Drosophila melanogaster collected from northern New York and northern Florida were compared at 18,21, and 25°C. 2. 2. New York flies had significantly higher rates of metabolism at incubation temperatures of 21 and 25°C but not at 18°C. 3. 3. A nested analysis of variance showed that at 2PC, 29% of the total variance in metabolic rate was due to between-population differences and 27% was due to line differences within populations. 4. 4. The metabolic rate characteristics of both groups of flies are consistent with their patterns of fecundity and seasonal abundance.

1. Descendents of a Florida, U.S.A. population of Drosophila melanogaster were reared under short (8 hr light: 16 hr dark) and long (16 hr light: 8 hr dark) photoperiods. 2. Flies reared under short photoperiods had higher rates of metabolism at 21 degrees C. 3. Because genetic background (iso-female line) affects metabolic rates, statistical control through analysis of covariance was necessary to isolate the effects of photoperiod on metabolic rates. 4. These results on a subtropical population of D. melanogaster are similar to those found on a temperate population of the same species.

1. 1. Second-generation descendents of wild-caught female Drosophila simulans Sturtevant collected at different seasons from Gainesville, Florida, USA, were reared under a constant temperature and food level but with seasonally variable photoperiods. 2. 2. Body weight and metabolic rate, after adjustment to a common body weight, were higher in descendents of flies collected in fall and winter. 3. 3. Temperature sensitivity (Q10) of metabolic rate was also related to season: higher Q10 values were associated with seasons of increasing temperatures and lower Q10 values were associated with seasons of decreasing temperatures. 4. 4. These metabolic characteristics may be adaptive in enhancing activity at lower temperatures and conserving energy at higher temperatures.

1. 1.|Descendents of Florida and Ithaca, U.S.A. populations of Drosophila melanogaster were reared under short (10 h light: 14 h dark) or long (14 h light: 10 h dark) photoperiods. 2. 2.|Flies were chilled for 8, 16, 32, or 64 min and the time to recovery was recorded. 3. 3.|Recovery time increased as chilling time increased. 4. 4.|Recovery time was also related to photoperiod; short-photoperiod flies recovered faster than did long-photoperiod flies. 5. 5.|These results together with earlier observations of higher metabolic rates of short-day flies indicate the importance of photoperiod in adaptively modifying physiological features.

The effect of a parasitic water mite, Hydrachna virella, on the stage distribution (the proportion of the host population represented by a stage) of its aquatic insect host, Buenoa scimitra, was studied using a stage-based matrix model. Despite killing members of several stages, the mite increased the stage-distribution values of those stages. This effect seems to result from a lag in the rate of development of parasitized hosts; parasitized hosts remain in a stage longer. Consequently, a stage with parasitized individuals would represent a larger proportion of the host population than would the same stage with only unparasitized individuals. Parasites that delay host development can bias field estimates of prevalence or proportion of a host population (or stage) parasitized.

COWLEY, J. M., R. T. BAKER, AND D. S. HARTE. 1992. Definition and determination of host status for a multivoltine fruit fly (Diptera: Tephritidae) species. J. Econ. Entomol. 85: 312-317. GIBBONS, J. D., I. OLKIN, AND M. SOBEL. 1974. Selecting and ordering populations: a new statistical methodology. John Wiley & Sons, New York, New York. HENNESSEY, M. K. 1994. Depth of pupation of Caribbean fruit fly (Diptera: Tephritidae) in soils in the laboratory. Environ. Entomol. 23: 1119-1123. HOWARD, D. F., AND P. KENNEY. 1987. Infestation of carambolas by laboratory-reared Caribbean fruit flies (Diptera: Tephritidae): effects of fruit ripeness and cultivar. J. Econ. Entomol. 80: 407-410. KNIGHT, R. J., JR 1982. Response of carambola seedling populations to Dade County's oolitic limestone soil. Proc. Florida State Hort. Soc. 95: 121-122. KOGAN, M., AND E. F. ORTMAN. 1978. Antixenosis-a new term proposed to define Painter's "nonpreference" modality of resistance. Entomol. Soc. America Bull. 24: 175-176. NORRBOM, A. L., AND K. C. KIM. 1988. A list of reported host plants of the species of Anastrepha (Diptera: Tephritidae). USDA-APHIS-PPQ Bull. 81-52. SAS INSTITUTE, INC. 1992. SAS', version 6.04. SAS Institute, Cary, North Carolina. SCHNELL, R. J., AND R. J. KNIGHT, JR 1989. Variation in isozyme alleles in Averrhoa carambola L. Proc. Interamerican Soc. Trop. Hort. 33: 127-132.

The effect of photoperiod on wing area of a mosquito in the species complex Anopheles quadrimaculatus was tested on adults reared from a field sample. Short-photoperiod [8:16 (L:D)] individuals of each sex had greater wing areas than did their long-photoperiod [16:8 (L:D)] siblings of the same wing length or body weight. The greater wing areas of short-photoperiod mosquitoes, given any wing length, established that short-photoperiod individuals had broader wings. The greater wing areas of short-photoperiod mosquitoes, given any body weight, established that short-photoperiod individuals had a greater wing area per unit body weight.

The surface-dwelling aquatic insect Hydrometra australis Say (Hemiptera: Hydrometridae) is difficult to rear. Although most field-collected nymphs reared on a diet of Drosophila in the laboratory develop to the adult stage, mate, and reproduce successfully (Lanciani 1975), only a small percentage of individuals reared from the egg stage on this food reach adulthood. In previous laboratory rearing attempts using different container sizes, different substrata, and Drosophila as food, the maximum survival I have observed in individuals reared from egg to adult is 40%. The closely related species Hydrometra martini Kirkaldy has been cultured on Drosophila (Sprague 1956), but its survival rate was not given. Collembolans have been cited as a common food source of hydrometrids, e.g., H. martini (Sprague 1956) and Hydrometra stagnorum (Linnaeus) (Arrow 1895). In northern Florida, H. australis can be often seen in the field feeding on aquatic collembolans, which are abundant in many shallow aquatic habitats frequented by H. australis. These observations suggested a rearing method for H. australis using aquatic collembolans as food. Six female H. australis were collected from Lake Alice, Gainesville, Florida, U.S.A. on 17-IX-1989, placed individually in plastic petri plates lined with moistened absorbent paper, and fed 3 frozen Drosophila melanogaster Meigen per day. Eggs removed from these plates to establish a laboratory parental generation were placed individually in plastic vials (3 cm in diameter and 7 cm in height) that were half to three-fourths full of water. The water surface was completely covered with plants of 2 species of duckweed, Lemna minor Linnaeus and Spirodela polyrhiza (Linnaeus). A circular hole cut in each vial cap was covered with a piece of screen. The vials were placed in a constant-temperature chamber held at 28?C with a 12-h light-dark cycle. Approximately 20 or more live collembolans (Sminthurides sp.) of various sizes collected from a local temporary pond were added to each vial when the Hydrometra eggs hatched. (Collembolans were easily field-collected by slowly skimming the duckweed-covered pond surface with the edge of a plastic box.) As the number of collembolans in the vials dwindled, more were added so that prey were always abundant. Uneaten collembolans survived well, so contamination by death of excess prey did not occur. As individuals of the parental generation of H. australis reached the adult stage, females and males were paired. The first 27 eggs laid, which were from two females, were then placed individually in plastic vials to establish the subject generation. This generation was reared as was the parental generation, except that the vials were removed briefly from the constant-temperature chamber 4 times each day (within the periods 7-9a.m., lla.m.-lp.m., 4-6p.m., and 8-lOp.m.) to be checked for molts. Twenty-six of the 27 subject-generation eggs successfully developed to the adult stage on an exclusive diet of collembolans. The mean stadium of each of the 5 immature instars is listed in Table 1. These stadia are consistently shorter than those (Lanciani 1975) determined on Drosophila-fed individuals (Table 1; P < 0.001 for each instar, t-test). The comparisons of instars 2 to 5 are not ideal because in the Drosophila-fed group, data for instars 2 to 5 were obtained from field-collected instars 1 to 4, respectively, that were maintained in the laboratory through the next instar only. The Collembola-fed

SUMMARYThe truncated negative binomial distribution is used to demonstrate water mite-induced mortality in a field population of the mosquito host Anopheles crucians. Consistent changes in the parameters of this distribution and in the number of hosts expected in higher mite load classes as truncation is applied to successively lower mite load classes suggest that many heavily parasitized individuals were missing from field samples. These changes are not observed in distributions derived from an association between parasitic larvae of another water mite, Hydrachna conjecta, and the insect Sigara ornata, which is apparently immune to this parasite. Although the method discloses parasite-induced mortality that is non-linearly related to parasite load, it fails to reveal linear parasite-induced mortality in a hypothetical example.

The number of larval water mites of the genus Arrenurus attached to the mosquito host Anopheles crucians was compared with the number of stylostomes present in the host tissues to determine the pattern of mite detachment from the host. All hosts carrying small and lightly pigmented mites had the same number of attached mites and stylostomes, indicating that detachment does not occur among mites that are not highly engorged. However, the number of attached mites was often less than the number of stylostomes in hosts carrying large and heavily pigmented mites, indicating that detachment does not necessarily occur synchronously at the time of oviposition of the mosquito but that some mites detach prior to oviposition. Survival of detached mites in laboratory rearings increased as individuals grew to lengths greater than 0.25 mm, a size that would place a mite in the larger and heavily pigmented class. If such mites fell into water as they left the host, they would stand a good chance of surviving.

SUMMARY. The life cycle of Hydrachna virella, a water mite parasitic on the notonectid backswimmer Buenoa scimitra, is described. The mite parasitizes immature instars 2–5 as well as adult males and females of the notonectid. Parasitized immature backswimmers spent longer periods of time between moults than unparasitized immature backswimmers. Initially attaching mites appeared to be generally distributed over the host body surface but previously attached mites that reattached after host ecdysis were found primarily on the dorsum of the thorax. The observed frequency distribution of mite larvae on the host was similar to that predicted by the negative binomial distribution.

The effect of parasitic larvae of the water mite Arrenurus pseudotenuicollis on adult, female mosquitoes of Anopheles crucians was determined from laboratory experiments on field-collected, nulliparous mosquitoes. The parasites significantly reduced the survivorship of both starved and raisin-fed, unengorged female mosquitoes. They significantly reduced the number of eggs produced by both field-engorged and laboratory blood-fed mosquitoes. In field collections of nulliparous An. crucians , the proportion of unengorged females bearing parasites was always higher and the average number of parasites carried by unengorged females was always greater than in engorged females. These results suggest that heavily parasitized females have a higher probability of dying before they feed on blood than do unparasitized or lightly parasitized females.

The effect of parasitic water mites on a natural population of their mosquito host was investigated by noting differences between the average number of mite stylostomes in 2 age groups of the host. In 6 consecutive samples, the average number of stylostomes was always higher in young than in old hosts, a consequence apparently of the higher mortality suffered by individuals that carried larger mite loads

SUMMARYEngorged, parasitic water mites were observed to decrease the growth rate and to increase the stadium length of nymphal backswimmers. Unengorged mites were found to have no effect on the host. The extended stadium lengths of parasitized hosts should reduce the instantaneous rate of natural increase of populations of parasitized hosts because this rate is sensitive to any factor that delays the onset of reproduction.

Recent studies have suggested that the stylostome of parasitic larval water mites of the genus Arrenurus Dugès is a product of the mite, not the host. We tested this hypothesis by comparing stylostomes of the similar species Arrenurus novimarshallae Wilson and Arrenurus pseudotenuicollis Wilson formed in each of two mosquito species, Anopheles crucians Wiedemann and Anopheles quadrimaculatus Say: if the stylostome is produced by the mite, not the host, then stylostome form is likely to be constant in different host species parasitized by the mite.The stylostome of A. pseudotenuicollis is a short, broad, convoluted sac, and stylostomes within the two host species did not differ significantly. The stylostome of A. novimarshallae is a long, thin, convoluted tube, and although it was significantly smaller in A. quadrimaculatus than in A. crucians, its form remained constant. Dark pigment deposits around the stylostome’s attachment point and along the tube may represent host defense that reduces stylostome growth in A. quadrimaculatus. Laboratory-reared A. novimarshallae often die after a brief engorgement period on A. quadrimaculatus but not on A. crucians.Thus, the stylostome of these two mite species has a consistent form in each of two host species, an observation compatible with the hypothesis that the stylostome is a product of the mite. In addition, the ease of distinguishing these two mite species on the basis of stylostome morphology attests to the potential value of the stylostome as a taxonomic character.

The effect of the parasitic water mite Hydrachna virella on its host Buenoa scimitra was investigated using laboratory experiments. The mite parasitizes all but the first instar of the host. Survival rates were found to be greater among unparasitized than parasitized individuals of these instars. Instantaneous death rates were observed to be linear functions of the number of mites supported/host. The mite's effect on the host's death rate appeared to be directly related to the size of the engorged mite compared to the size of the host; greater relative sizes were associated with greater impacts. Unparasitized females oviposited significantly more eggs than parasitized females, and the instantaneous birth rate of the host was observed to be a non-linear function of mite load.

Resource partitioning was studied in 20 species of the water mite genus Eylais, the larvae of which parasitize adult Coleoptera and Hemiptera living in shallow ponds. Co—existence of sympatric species is possible because the mites exploit host resources in different ways. Most commonly they parasitize different species, but when hosts are identical, the mites remain segregated by differences in the precise site of attachment, biotope, or season of parasitism. Mite biology, host dispersal, and competition for attachment sites from other water mite species may restrict further subdivision of host resources. See full-text article at JSTOR

All active stages of the marsh treader Hydrometra myrae Bueno are attacked by larvae of the water mite Hydryphantes tenuabilis Marshall, but the parasitic mites become fully engorged on only adult hosts. All mites attach for the 1st time by jumping onto the host from the water surface, but as the host molts, the mites crawl to the next instar. Initially attaching mites predominate on the venter and legs; transferring mites on the dorsum of the host. Adult hosts bear mites of similar sizes on the dorsum because transferring mites attach simultaneously and engorgement proceeds at the same rate, but they carry mites of smaller and variable sizes on the venter and legs because initially attaching mites can parasitize the host for as long as 6 or 7 days after ecdysis. The incidence of parasitized hosts and the mean number of mites per host increase as the host develops from instar I to the adult. Mite loads appear to be linearly related to host age.

The metabolic rates of 4-day-old Drosophila simulans females are affected by sexual activity. Virgin females have the lowest rates of metabolism, inseminated females that were separated from males had higher rates of metabolism, and females that were kept continuously in contact with males had the highest rates of metabolism. Differences between the metabolic rates of the latter two classes of females are unrelated to differences in their rates of egg laying.

1. 1. Increasing incubation time over which metabolism is measured can provide reasonable estimates of metabolic rates in species with diel cycles. 2. 2. The rates of metabolism of Drosophila melanogaster and D. simulons were measured over consecutive 1-hr intervals to confirm the existence of diel variation. 3. 3. These hourly measurements were integrated over 4- to 9-hr intervals to simulate long incubation times. 4. 4. The estimates of metabolic rate obtained from the 4- to 9-hr intervals closely agreed with the average hourly measurements in both species. 5. 5. Consequently, experiments requiring long measurement intervals that may include periods of fluctuating metabolic rates can provide valid comparative estimates of energy expenditures.

The effect of 2 species of water mites on the instantaneous death rate of their hosts was measured on the basis of laboratory experiments. In both parasite-host association — the parasitic water mite Hydryphantes tenuabilis on the aquatic insect host Hydrometra australis and the parasitic water mite Arrenurus pseudotenuicollis on the mosquito Anopheles crucians — the effect of mite load on the instantaneous death rate of the host appeared to be linear. Also, the impact of a single parasite on the host's death rate was apparently related to the ratio of parasite to host body weight. The results of this study are in general agreement with recent theoretical investigations of the regulation of host populations by parasites.

Pigmented eyespot size of the benthic cladoceran Simocephalus exspinosus was measured in individuals sampled from four freshwater ponds that differed in the extent of visually-oriented predation. In ponds with such predation (from fish, salamander larvae, and dragonfly nymphs), eyespot size was found to be significantly smaller, relative to body size, than in a pond without visually-oriented predation. Reduction in pigmented eyespot size may represent an adaptation to reduce vulnerability to predation.

The life cycle of the water mite Tyrrellia circularis Koenike has been described (Lanciani, 1978, Mosquito News 38: 282-284). The larvae, which inhabit the moist margins of standing and flowing water as do the other stages of the species, seek out and cling to the pupae of at least 2 species of ceratopogonids: Dasyhelea mutabilis (Coquillett) and Dasyhelea grisea (Coquillett). As the fly emerges, the mites crawl from the pupal skin and attach to the abdominal segments of the adult. After 3 to 7 days (at 27 C), most larvae have become fully engorged, leave the host, and, if they are close to an aquatic site, return to their habitat, where they metamorphose to the nymphal stage. The nymphs, unlike the larvae, are predatory, but prey generally on the same species as parasitized by the larvae. Nymphs have been observed to prey on eggs, larvae, and pupae of Dasyhelea species as well as species of other cer

The metabolic rates of adult female Drosophila melanogaster Meigen were measured on single individuals in "closed system" metabolic chambers. Adults whose parents were reared under short-day conditions (8 h light: 16 h dark) had significantly higher metabolic rates than did adults whose parents were reared under long-day conditions (16 h light: 8 h dark). These results together with those of a previous study indicate the importance of photoperiod experienced by the subject and the subject's parents on metabolic rate.

The metabolic rates of wild-caught adult female Drosophila melanogaster measured at 22@*C are significantly greater than those of sympatric Drosophila simulans. Similarly, the temperature-specific metabolic rates, measured at 18, 22, and 25@*C, in laboratory-reared granddaughters of the wild-caught D. melanogaster are greater than those of the laboratory-reared granddaughters of the wild-caught D. simulans females. These genetically encoded differences in metabolic rate between the two species may be related to differences in fecundity and seasonality.

Bledius-Arten. Acta Soc. Fauna Flora Fennica 56 (3): 1-24. PAUTLIAN, R. 1941. Les premiers 6tats des Staphylinoidea. M6m. Mus. Natn. Hist. Nat., Paris (n.s.) 15: 1-361, pl. 1-3. RICHARDS, L. J. 1983. Feeding and activity patterns of an intertidal beetle. J. Exp. Mar. Biol. Ecol. 73: 213-24. STE-CLAIRE DEVILLE, J. 1924. Kleinere Mitteilungen uiber die DyschiriusArten Europas. Koleopt. Rundschau 11: 20-4. WHITEHEAD, D. R. 1969. Notes on Dyschlirius Bonelli and Akephorwus LeConte, with a peculiar new Dyschlirius from Texas (Coleoptera: Carabidae: Scaritini). J. New York Ent. Soc. 77: 179-92.

Hydrachna virella (Acari: Hydrachnellae), a new species of water mite that parasitizes backswimmers of the species Buenoa scimitra Bare (Hemiptera: Notonectidae), is described. Adults and nymphs are characterized by a pronounced elongation of the posteromedial portion of the 4th coxae. Larvae are distinguished by the relative sizes of the coxal plates and by the positions and relative sizes of the coxal plate setae.

The size of the parasitic stage of the water mite Hydrachna virella decreases as the number of parasites on the host, Buenoa scimitra, increases. Logarithmic transformation revealed that the two variables, mite size and number of mites per host, were linearly related. The size of the host affected the nature of the relationship in two ways. First, the bigger the host, the bigger was the mite at any given number of mites per host. Second, the bigger the host, the smaller was the rate of decline in mite size as number of mites per host increased. Crowded mites were likely to have a reduced fitness because of delayed maturation or lower fecundity. Even though mite size declined as the number of attached mites increased, a previous study has shown that host damage induced per mite remains constant.

observations of Cyphoderris (Orthoptera: Haglidae) with a description of a new species. Psyche 85: 147-167. SHAROV, A. G. 1971. Phylogeny of the Orthopteroidea. Trans. Instit. Paleont. 118: 1-251. (English translation). SPOONER, J. D. 1973. Sound production in Cyphoderris monstrosa (Orthoptera: Prophalangopsidae). Ann. Entomol. Soc. America 66: 4-5. WALKER, T. J., J. A. REINERT, AND D. J. SCHUSTER. 1983. Geographical variation in flights of the mole cricket, Scapteiiscus spp. (Orthoptera: Gryllotalpidae). Ann. Entomol. Soc. America 76: 507-517.