Showing papers in "Journal of the Kansas Entomological Society in 2003"

Floral sonication by bees: Mesosomal vibration by Bombus and Xylocopa, but not Apis (Hymenoptera: Apidae), ejects pollen from poricidal anthers

Abstract: Vibration accelerations and displacements were measured in Bombus spp., Xylocopa spp., Apis mellifera L., and Eristalis tenax (L.) (a syrphid flower fly) including the first measurements of thoracic displacements during untethered free flight, and floral sonication by Bombus terrestris (L.). For all except A. mellifera the thoracic displacement during sonication is less than during flight but the frequency is greater. Thus, thoracic acceleration during sonication is greater than during flight for this bee species. However, the sonication frequency of A. mellifera, the honey bee, did not differ significantly from flight frequencies. Its accelerations were lower than required to eject pollen from sonication-pollinated flower anthers having poricidal dehiscence (e.g., Solanum spp.). The vibration mode shape of X. californica arizonensis Cresson, a large carpenter bee, was determined, demonstrating that sonication was produced by the same mechanism as flight. However, for Xylocopa, the sonication frequency stimulated resonant frequencies of both head and abdomen, enhancing acceleration forces transmitted during sonication of flowers. Sonication vibration of the thorax occurred at the second harmonic frequency of the fundamental flight frequency, but the natural frequency of the thorax with the wings decoupled could not explain the higher sonication frequency. It is proposed that the higher frequency is produced by the second harmonic of the indirect flight muscle stretch activation response. The power requirements for sonication by bees is presumably less than during flight such that muscular displacements at the second harmonic frequency of the stretch activation response is adequate to drive this highly evolved morphological, physiological and behavioral system of pollen harvesting. Our results explain the observation that Apis mellifera, the common honey bee, does not use floral sonication in its pollen foraging behavioral repertoire.

Effects of slope and particle size on ant locomotion: Implications for choice of substrate by antlions

Abstract: Antlions construct conical, mechanically unstable pits in sand for prey capture. If ants (a major prey item) have difficulty walking on inclined sand surfaces, this may explain the effectiveness of their capture by this trap design. We investigated the degree to which locomotion of ants is impaired on sandy slopes. The locomotion of ants, physical characteristics of sand, steepness of antlion pit walls, and sand-size preference of antlion larvae were evaluated using four size fractions of sand (0.1-0.25, 0.25-0.50, 0.50-0.71, and 0.71-1.0 mm diameter). An ant's probability of falling when walking on a sandy slope increased with increasing slope angle or decreasing sand-particle diameter. For a given particle size and angle of inclination, larger ants were more likely to fall and roll uncontrollably than smaller ants. The maximum inclination above horizontal (angle of repose) for sand of different particle sizes was measured. The angle of repose was higher for the finest sand fraction than for the three coarser sand fractions, but did not differ among these three coarser fractions. In each sand fraction, the steepness of pits constructed by antlions was not significantly different from the angle of repose. Antlion larvae preferentially built pits in the two finer sand-size fractions.

Bee species of Nova Scotia, Canada, with new records and notes on bionomics and floral relations (Hymenoptera: Apoidea)

Abstract: Pollination is one of the most important processes in terrestrial ecosystems, leading to reproductive success within many plant communities. Pollination, for most angiosperms, is animal mediated, insects being the most important pollinators. Bees (Hymenoptera: Apoidea) are the most highly adapted of all anthophiles (flower visitors), possessing many anatomical and behavioral adaptations suiting a lifestyle completely dependant on floral resources. This dependence makes bees the most important of all pollinators, and as such, they are keystone components of almost all terrestrial ecosystems. Although there is historic knowledge of the importance of bees in agricultural plant communities, only recently has there been an appreciation of the fragility of many plant-pollinator relationships. Therefore, understanding the complex interactions of plants, pollinators and the ecosystems surrounding these relationships is crucial, especially when considering conservation of the species or their respective habitats. A key step in understanding these relationships is knowing which organisms are involved. This paper provides an annotated checklist of bee species in Nova Scotia, Canada, and includes summaries of their bionomics and floral relations. To date, 157 indigenous bees and two recently introduced species, representing 26 genera from six families, have been reported for Nova Scotia. New additions to the bee faunal record of Nova Scotia (based on the literature examined) include Agapostenion (Agapostemon) virescens (Fabricius), 1775; Andrena (Melandrena) dunningi Cockerell, 1898; Anthophora (Clisodon) furcata terminalis Cresson, 1869; Bombus (Pyrobombus) impatiens Cresson, 1863; Calliopsis (Calliopsis) andreniformis Smith, 1853; Colletes validus Cresson, 1868; Hoplitis (Alcidamea) producta producta (Cresson), 1864; Hylaeus (Prosopis) modestus modestus Say, 1837; Megachile (Megachile) relativa Cresson, 1878; Osmia (Nothosmia) tersula Cockerell, 1912; Perdita (Perdita) octomaculata octomaculata (Say), 1824: Protandrena (Pterosarus) nebrascensis nebrascensis (Crawford), 1903; Stelis (Stelis) foederalis (Smith), 1854; and Stelis (Stelis) subemarginata (Cresson), 1878.

Dominant-subordinate relationships in a facultatively social, nocturnal bee, Megalopta genalis (Hymenoptera: Halictidae)

Abstract: The potential for the formation of social relationships was explored for the facultatively social halictine bee, Megalopta genalis, using experimental circular arenas. Observing pairs of females from different nests, we examined the initiation of agonistic behavior, and the expression and relative frequency of dominance behavior in terms of phenotypic differences between interacting bees. Within pairs older females with relatively larger ovaries tended to be dominant over younger females with smaller ovaries, and females with fewer nest-mates tended to initiate agonistic interactions. Bees also modified their behavior over a 24-hour time frame and were more pacific when paired with the same bee in repeated trials. Our observations suggest that these predominantly solitary bees have the capabilities to express cooperative and social dominance behavior typical of the halictines with obligate social behavior.

Activity of spinosad against adults of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) is not affected by wheat temperature and moisture

Abstract: Spinosad, a commercial bacterial pesticide. was evaluated against adults of the lesser grain borer, Rhyzopertha dominica (F.), on 12.5 or 14.5% moisture wheat stored at 22, 28, and 34°C. Adults of R. dominica were exposedfor 14 days to untreated wheat and wheat treated with spinosad at 0.1 and 1 mg (AI)/kg every month for four months. Mortality of adults exposed to untreated wheat ranged from 0 to 39%. All R. dominica adults exposed to spinosad-treated wheat were killed. The activity of spinosad during the four-month test period was not affected by the three temperatures and two moisture levels tested.

Trap-nesting bees and wasps on the university campus in Sao Paulo, southeastern Brazil (Hymenoptera: Aculeata).

Abstract: This paper reports the species of solitary bees and wasps nesting in wooden trap-nests on the campus of the University of Sao Paulo (23°33'S, 46°43'W), in southeastern Brazil, during three years (1998-2001). The wooden trap-nests offered circular holes 3 to 10 mm in diameter, drilled 5 to 12 cm deep. Rolled papers were inserted in the hole, so that the paper tube could later be periodically extracted to reveal the nest. Females of eight species of bees and eleven species of wasps occupied a considerable percentage of the trap nests. The two predominant bee species in the first two years were Tetrapedia diversipes Klug and Anthodioctes megachiloides Holmberg, while in the third year the population of Hylaeus spp. increased considerably and T diversipes decreased. Wasps of the genus Trypoxylon were abundant during the studied period, and in 2001 populations of non-native Passaloecus pictus Ribaut increased. Natural enemies of the trap nest occupants were fungi mites and Melittobia wasps.

Parasitic behavior of Leucospis cayennensis Westwood (Hymenoptera: Leucospidae) and rates of parasitism in populations of Centris (Heterocentris) analis (Fabricius) (Hymenoptera: Apidae: Centridini)

Abstract: The parasitic behavior of Leucospis cayennensis Westwood, the rates of parasitism and other mortality factors in populations of Centris analis (Fabricius), were studied on the campus of the University of Sao Paulo, Ribeirao Preto, SP, Brazil, from May 1996 to April 1999. The host species nested in cardboard trap-nests. Parasite activity was monitored throughout the host's nesting periods. The attacks to the nests began from one to five months after the nesting activities of the host had been initiated and ended within one month after nesting activity stopped. The parasites attacked the cells in several ways: 1) ovipositing through the side wall of the nest; 2) by entering the unplugged or abandoned nests and ovipositing through the cell partition of the last constructed brood cell; 31 by breaking through the nest plug, entering the nest and ovipositing through the cell partition or, 4) by trying to reach the host cell by inserting their ovipositor through the nest plug and cell partition Most attacks were made on cells containing host prepupae or pupae. The eggs were placed inside the host cocoons attached to the lateral wall of the cocoon, to the cellular partition, or on the surface of the host. The total duration from attack to adult emergence took 24 to 56 days for females and 23 to 49 days for males. Leucospis cayennensis was the most destructive enemy of C. analis, accounting for 83.8% and 91.7% of parasitized cells in each year Coelioxys sp. and Mesocheira bicolor (Fabricius) were the other insect parasites associated with the nests of C. analis.

Gene Flow and Population Structure in an Oligolectic Desert Bee, Macrotera (Macroteropsis) portalis (Hymenoptera: Andrenidae)

Abstract: Seven microsatellite loci from 176 female specimens of the oligolectic desert bee, Macrotera portalis, were analyzed to detect population subdivision among eight geographically distinct localities (17 to 342 km apart) across southwestern New Mexico and southeastern Arizona. In spite of the absence of obvious geographic barriers to gene flow, genie and genotypic frequencies revealed significant genetic heterogeneity among localities. F statistics revealed a high level of inbreeding within populations (F i s = 0.3241, P < 0.001), as well as substantial differentiation among localities (F s t = 0.2037, P < 0.001). A significant correlation was detected between distance among populations and the level of gene flow. Various factors may contribute to the low level of gene flow observed among populations, including narrow host-plant specificity, specificity in soil composition, habitat specificity, and the existence of large-headed, flightless males that mate within the nests. Five microsatellites from 192 male and female Macrotera portalis (Timberlake) reared from nests were analyzed in order to estimate intra-nest relatedness. Relatedness among female nestmates was significantly greater than zero for two of seven nests. Our results have implications for understanding patterns of bee diversity.

Bees of the Hawaiian Islands, Exclusive of Hylaeus (Nesoprosopis) (Hymenoptera: Apoidea)

Abstract: In addition to the endemic species of Hylaeus, subgenus Nesoprosopis, there are fifteen species of bees present in the Hawaiian Islands, all presumed to be adventive here, even though the origins of three species {Megachile timberlakei Cockerell, Ceratina sp. nr. dentipes Friese and Xylocopa sonorina F. Smith) remain unknown. A species of sweat bee, Lasioglossum {Dialictus) impavidum (Sandhouse), is here recorded from the Islands for the first time; this species is native to the western United States (California). It is now established on the Island of Oahu. A key, with accompanying illustrations, is provided for the identification of these bees and each species is briefly discussed. It has been a full century since Perkins (1899) treated the entire bee fauna of the Hawaiian Islands. At that time, he reported only five species of bees other than the clearly native members of Nesoprosopis (now treated as a subgenus of the cosmopolitan genus Hylaeus) (Colletidae). He recorded Xylocopa sonorina F. Smith (as X. aeneipennis Perkins) (Apidae), Megachile diligens F. Smith, M. umbripennis F. Smith (as M. schaunslandi Alfken), M. gentilis Cresson (described as a new species, M. palmarum Perkins) (Mega chilidae), and the European honey bee, Apis mellifera L. (Apidae), which had been intentionally introduced in 1857. Of the three Megachile species he postulated that only M. diligens might be native. All of these species are separated in the key given below; authors of each are indicated in the species accounts following the key. Over the next 100 years further accidental introductions brought the total to 12 species (Nishida, 1997), exclusive of the Nesoprosopis species. Additional adventive species, including the first representative of the family Halictidae, have since been discovered on the Islands, bringing the total to 15. All of these species are separated in the key given below. The two species of European origin (Hylaeus leptocephala Morawitz and Apis mellifera) no doubt arrived by way of North America where both are now common and widespread. Four other species (Ceratina arizonensis Cockerell (Apidae), Xylocopa sonorina, Lasioglossum impavidum (Sandhouse) (Halictidae) and Megachile gentilis) are adventive arrivals from the western North American fauna. The remaining nine species are all from the Eastern Hemisphere, from Southeast Asia to Australia; doubtless some arrived in Hawai'i via the South Pacific Islands. Of the adventive species, only Apis mellifera, Xylocopa sonorina, Ceratina nr. dentipes and Lasioglossum impavidum are regularly found in non-coastal areas. The distribution of A. mellifera extends to elevations of about 3000 feet, while L. impavidum has an elevational amplitude from sea level to about 9000 feet. All the megachilids appear to be restricted to coastal areas. (Karl Magnacca, pers. comm.). The material on which this study is based is largely from two sources: the B. P. Bishop Museum (BPBM), Honolulu, and the Natural History Museum of Los Angeles County (LACM), Los Angeles. Additional specimens from the Essig Entomological Museum of

Sex allocation, nests, and prey in the grass-carrying wasp Isodontia mexicana (Saussure) (Hymenoptera: Sphecidae)

Abstract: At six locations in Montana, Isodontia mexicana (Hymenoptera: Sphecidae) nested either in trap nests or in commercial "bee boards" used for alfalfa leafcutting bees. Partitions and plugs in the nests were constructed fromfragments of grass stems gathered by females, who provisioned nests containing 1-6 cells with either tree crickets (Gryllidae: Oecanthinae, Oecanthus) or katydids (Tettigoniidae: Conocephalinae, Conocephalus). The number of prey per cell, but not cell length or cell volume, was a significant predictor of offspring size. Isodontia mexicana displayed differences between the sexes typical of Sphecidae, having larger females that received more investment from their mothers, that occupied cells deeper within nests, and that emerged as adults later in the season on average than males. Finally, by taking unequal numbers of male and female prey, I. mexicana may impose sex-biased selection pressure on their prey populations.

Nestmate Recognition Assays As a Tool for Population and Ecological Studies in Eusocial Insects: A Review

Abstract: Nestmate recognition bioassays are useful in detecting the dispersion of eusocial insect colonies. They also allow investigators to draw inferences concerning the degree of genetic similarity among nestmates and between worker eusocial insects from neighboring colonies. The objectives of this review are to: 1) establish the reliability of nestmate recognition bioassays, as used in ecological studies, 2) provide guidance for investigators who wish to design nestmate recognition bioassays, and 3) suggest future applications of nestmate recognition bioassays in ecological studies of eusocial insects. While investigators have utilized nestmate recognition bioassays in some ecological studies, these assays still have great potential for giving additional insights to our understanding of colony dispersion and of competitive interactions among eusocial insect colonies.

An anteonine wasp in Cenomanian-albian amber from Myanmar (Hymenoptera: Dryinidae)

Abstract: Burmanteon olmii, a new genus and species of anteonine wasp (Dryinidae) is described and figured from a single female preserved in Cretaceous (Cenomanian-Albian) amber from Myanmar (Burma). This fossil is presently the oldest record for its subfamily (and the second oldest for its family) which has hitherto been known only from Middle Eocene Baltic amber. A revised key to the genera of Anteoninae incorporating the new fossil genus is provided.

Ichnotaxonomy, origin and paleoenvironment of Quaternary insect cells from Fuerteventura, Canary Islands, Spain

Abstract: On Fuerteventura, Canary Islands, micritic and silty to sandy insect cells are abundant, in well-exposed Quaternary terrestrial sediments and calcretes. Previous authors regarded these cells as hymenopteran in origin, referring them to the ichnogenus Celliforma. However, a new study of cell shape, cell wall thicknesses, cell lining, apertural closure, construction materials and cell aggregation and clustering, indicates that some of these fossils may be referable to the ichnogenus Palmiraichnus or an unnamed ichnogenus of the Celliformidae, attributed to bees. Other cells are referable to the ichnogenus Rebuffoichnus, considered to be coleopteran pupal cells. Similarities between this Quaternary assemblage and better-known Late Cretaceous to Early Tertiary insect cell assemblages from South America, support an earlier suggestion that the Fuerteventuran cell assemblages developed during periods of relatively increased rainfall in an overall semiand paleoclimate.

Biological Impediments to Measures of Competition Among Introduced Honey Bees and Desert Bees (Hymenoptera: Apiformes)

Abstract: Foraging behaviors, host plant breadth, and vagilities of social and solitary bee species differ dramatically. We illustrate how these phenomena can obscure the effects of floral re source competition from our studies on a species-rich, native bee fauna that visit the flowers of cre osote bush (Larrea tridentata Coville (Zygophyllaceae)), a widespread dominant perennial plant species in the warm deserts of North America. The potential for competition among the solitary bees that visit creosote bush and honey bees was investigated by two methods; one that is widely used asks if solitary bee abundance and species diversity is less at sites with greater honey bee abun dance; and a second, more novel approach that asks if pollen availability is limiting at sites with high bee biomass. We found no relationship among number of honey bees at sites and species rich ness and abundance of all native bees combined or of pollen specialist species considered alone. Protein represented in the pollen of the primary host plant greatly exceeded the biomass of bees present at a site. We suggest bee populations are rarely pollen limited in this system or that com petition, when it occurs, is highly episodic. Future studies of bee competition will need to assess long-term population variation among solitary and introduced bees in habitats where floral resources can be measured for multiple flowering plant species, and where bee colony/nest dynamics can be documented. Studies of bee faunas in temperate areas are needed. This paper demonstrates some of the possible pitfalls for studies of competition among highly eusocial and solitary bees. We conclude that basic data on bee biology and population dynamics are needed before these questions can be satisfactorily answered and, at present, little hard data are available to evaluate the competing hypotheses.

Ecology of two burrowing wolf spiders (Araneae: Lycosidae) syntopic in Florida scrub: Burrow/body size relationships and habitat preferences

Abstract: This fourteen year long study in the Florida scrub on the Lake Wales Ridge demonstrated that visually searching for open burrows of Geolycosa spiders was an effective method for sampling populations in the winter dry season, except one year when abnormally high precipitation during an El Nino event caused many spiders to close their burrows. Not only could the two endemic Geolycosa species be identified by the architecture of their burrow entrances (G. xera archboldi McCrone was aturricolous and G. hubbelli Wallace was turricolous), but the diameter of the burrow opening was highly correlated with the size of the resident spider and the volume of its burrow. The two syntopic Geolycosa species preferred different microhabitats: G. xera archboldi regardless of size was found in barren sand (0-10% litter coverage) whereas G. hubbelli shifted preference as it grew in size (going from 20 to 80% litter coverage). In addition each species exhibited significant habitat preferences: G. xera archboldi was most common in sand pine scrub with rosemary, the most xeric and least common habitat in the scrub; G. hubbelli was most abundant in scrubby flatwoods with sand live oak and in ridge sandhill with scrub hickory, both of which are relatively mesic sites with open canopies.

A preliminary account of the bees of Colombia (Hymenoptera: Apoidea): Present knowledge and future directions

Abstract: An account of the present knowledge of the bee fauna of Colombia is given. Although substantial work has been done on the bees of the world as a whole,there are few works on the bees of Colombia, and most of them focus onidentification of the species of the few groups (mostly meliponines) for which there are specimens in local collections. Other works include some regional surveys and some ecological or behavior (nesting and foraging) studies. An updated list of the species of bees currently known is presented, along with some suggestions for future studies of Colombian bees.

Nesting and social behavior of a wood-dwelling Neotropical bee, Augochlora isthmii (Schwarz), and notes on a new species, A. alexanderi Engel (Hymenoptera: Halictidae)

Abstract: The nesting biology and social behavior are described for Augochlora (Augochlora) isthmii Schwarz at the species' type locality (Barro Colorado Island, Republic of Panama). Bees nested in a fallen log with wood that wasstill solid. Nests of A. isthmii sometimes contained more than one female, suggesting some form of social behavior, while other females nested alone. Pollen taken from nest cells was almost exclusively (>95%) from a single species of Rubiaceae (nr. Warscewiczia coccinea) that is rare on BCI. An occupied nest of a second, related species (A. alexanderi Engel, new species) was discovered in a tree branch in southern Colombia, supporting the conclusion that females of the repandirostris species-group regularly use wood as a nesting substratum. We provide the first taxonomic descriptions of the male of A. isthmii and both sexes of A. alexanderi; we also redescribe the female of A. isthmii. The evolution of social behavior in the "Augochlora group" is briefly considered in light of available information.

Grasshoppers (Orthoptera: Acrididae) and black-tailed prairie dogs (Sciuridae: Cynomys ludovicianus (ord)): Associations between two rangeland herbivores

Abstract: We collected data on the density and species composition of grasshoppers on and off three black-tailed prairie dog (Cynomys ludovicianus) towns in the northern mixed-grass prairie of Badlands National Park (BNP), South Dakota during July of 1997 and July-August 1998. Densities of grasshoppers were significantly higher on prairie dog towns than off in July 1997. In 1998, densities were again significantly higher on towns in July, but lower on towns in August. Species from three Acrididae subfamilies, Melanoplinae, Gomphocerinae, and Oedipodinae, were collected at the BNP. Melanopline species comprised the largest proportion of grasshoppers collected both on and off prairie dog towns in both years, gomphocerine species were found almost exclusively off towns, while oedipodine species were significantly more common on towns. In 1998, the stage of the grasshoppers was also recorded. The proportion of melanopline and oedipodine nymphs that were collected on towns was significantly greater than the proportion collected off towns in July 1998. By intensively grazing in the vicinity of their burrows, black-tailed prairie dogs create areas of bare ground which may provide ideal oviposition sites and preferred habitat for some species of grasshopper.

Antennal morphology of the soybean stemborer Dectes texanus texanus LeConte (Coleoptera: Cerambycidae)

Abstract: The antennal receptors of the soybean stemborer, Dectes texanus texanus LeConte. were examined with a scanning electron microscope. Male and female antennae have nine segments. and have a dense covering of sensilla chaetica. Structurally, there are three types of sensilla chaetica: I, II and III. Types I and II protect the underlying sensilla basiconica located on the distal eight segments, while type III appears to limit antennal movement at the junctions of flagellomeres. Blunt, curved basiconic pegs are found on both sexes and are the main olfactory sensilla. Morphologically distinct contact chemosensilla are also located on the tips of male and female antennae. The putative function of these sensilla is discussed.

Characterization of bean leaf beetle (Coleoptera: Chrysomelidae) flight capacity

Abstract: Bean leaf beetle, Cerotoma trifurcata (Forster) (Coleoptera: Chrysomelidae), flight capacity was measured using a computer-monitored tethered-flight mill. Beetles were collected from soybean (Glycine max (L.)(Fabaceae)) and alfalfa (Medicago sativa L.(Fabaceae)) fields in 2000 and 2001. The number of individual flights, flight duration, and flight distance were recorded for a 24-hr period. Eighty-nine percent of beetles made at least one flight, and the mean number of individual flights per beetle was 25.59 ′ 5.88 (mean ′ SE). The mean total-flight duration was >9 min, and the longest duration of a single flight was >38 min. Seventy-one percent of beetles flew 301 m. The farthest flight made by an individual beetle was 4.9 km. The mean flight distance of all beetles flown was 166.01 ′ 45.38 m. Beetles collected in August flew farther than beetles collected in any other month. There was a strong positive relationship between flight distance and flight duration but not between flight distance and the number of individual flights. The presence of ectoparasitic mites and ovarian stage did not affect flight capacity.

Nest and Provisioning Biology of the Bee Panurginus polytrichus Cockerell (Hymenoptera: Andrenidae), with a Description of a New Holcopasites Species (Hymenoptera: Apidae), Its Probable Nest Parasite

Abstract: The nest architecture, mating behavior and nest provisioning biology of Panurginus polytrichus in central Texas are described. Panurginus polytrichus is a vernal, univoltine, gregari ous, polylectic bee. The main nest site studied has been continuously occupied for at least 20 years. Most mating takes place at the nest site. Mating balls are commonly observed at the emergence site and mating pairs often make short flights while in copula. Nests may have multiple entrances but are occupied by a single female. Nests have an unusual, horizontal sand filled vestibule which the female traverses to reach the open, vertical main burrow. Females usually make three or four pollen trips per day and are estimated to provision a male cell in one day and a female cell in two. Hol copasites rozeni n. sp., a probable nest parasite of P. polytrichus is described. It is the first parasitic bee associated with any species of Panurginus and a possible biological link with the Old World ammobatoidine bees. Panurginus is the only member of the Panurgini occurring in the Western Hemisphere, and the only Holarctic genus in the Panurginae, a group whose 2000+ species make it the largest subfamily of bees in North America (Michener et al, 1993). The taxonomy of Pa nurginus remains unsettled. Eighteen species are currently recognized from North America but there is no modern revision and some currently recognized taxa may actually be com posite entities (Thorp and Leong, 1997). There appear to be as many as 34 Old World species, including ten species of Clavipanurgus, a group which may deserve generic sta tus (S. Patiny, pers. com.). While there are scattered reports on various aspects of the bi ology of a number of Panurginus species, overall knowledge of the biology of the genus remains poor. Detailed reports on nest architecture are available for just two of the Old World species (Malyshev, 1924; Rozen, 1971) and two of the 18 North American species

Behavioral interactions among females of Halictus (Seladonia) lanei (Moure) (Hymenoptera: Halictidae)

Abstract: Halictus (Seladonia) lanei (Moure) has the most extreme cephalic dimorphism, and thereby presumably also caste dimorphism, among the halictine bees. Previously known only from a few sites in Brazil, additional localities for this species are documented, including the first records for it from Bolivia, and a distribution map is provided. In order to investigate the possible social organization of this species in the absence of nest excavations, circle tube experiments were performed. In these arenas pairs of putative workers of this species generally behaved very aggressively, on average more so than any of the other halictine species studied with this apparatus. One pair, however, acted very cooperatively and perhaps they were nestmates. The circle tube behaviors are consistent with the species being eusocial, a fact also supported by the strong size dimorphism and comparisons with its sister species.

Biology and behavior of a seasonally aquatic bee, Perdita (Alloperdita) floridensis Timberlake (Hymenoptera: Andrenidae: Panurginae)

Abstract: The small panurgine bee, Perdita (Alloperdita) floridensis Timberlake, nests in sand during mid-April to mid-May in south-central Florida, This species is solitary, but often nests gregariously in dense aggregations. It is univoltine, with some larvae delaying emergence by a year, and is oligolectic, primarily foraging on gallberry, ilex glabra (L.) Gray. Details of nest construction, foraging, pollen transport and provisions, activity periods, and male behaviors are described. Mating is presumed to occur within nests and was never observed on host plants. Bees over-wintered as post-defecated larvae (prepupae) in a semi-diapause. The biology and behaviors associated with a prolonged period (five to six months) underwater for some prepupae are detailed, and the possible oxygenating role of algae in their survival is discussed. Predators and parasites associated with P floridensis include: the cleptoparasitic bee, Sphecodes brachycephalus Mitchell; two mutillids, Pseudomethoca torrida Krombein and Dasymutilla archboldi Schmidt and Mickel; an undetermined species of mite; the asilid fly, Mallophorina clausicella (Macquart); and the harvester ant, Pogonomyrmex badius (Latreille). In addition, an undetermined nematode species, and mosquitofish, Gambusia holbrooki Girard were associated with P. floridensis nest sites.

A list of the lady beetles (Coleoptera: Coccinellidae) of North Dakota with new records from North Dakota and Minnesota

Abstract: A checklist of the 54 species of Coccinellidae (Coleoptera) known from North Dakota is presented including five new state records for North Dakota: Brachiacantha tau LeConte, Hyperaspidius wolcotti (Nunenmacher), Hyperaspis lateralis Mulsant, Hyperaspis proba (Say), and Harmonia axyridis (Pallas). Five new state records for Minnesota are also reported: the first two above listed species, with Brachiacantha decempustulata (Melsheimer), Hyperaspis inflexa Casey, and H. brunnescens Dobzhansky. The rapid spread of H. axyridis in North Dakota is noted.

A male sleeping roost of a sweat bee, Augochlorella neglectula (Ckll.) (Hymenoptera: Halictidae), in Panamá

Abstract: A persistent sleeping roost is described for male sweat bees, Augochlorella neglectula (Ckll.), occurring on the rootlets of a hanging plant on a 4th story apartment balcony in an urban environment in central Panama. The rootlets were used by the same males consistently within a season, as well as between seasons, although presumably different individuals were involved. Males probably do not use olfactory cues for local orientation to the sleeping rootlet, as inferred from choice tests between an un-used and used rootlet. Brief social interactions among males were generally pacific, although there was kicking and shoving when they first settled. Males became progressively more difficult to disturb further into the night.

Ovaries, ovarioles, and oocytes in apoid wasps, with special reference to cleptoparasitic species (Hymenoptera: Apoidea: Sphecidae )

Abstract: The number of ovarioles and the size and number of mature oocytes of apoid wasps are explored. New data are provided for 68 species in 39 genera, all species and 25 genera being studied for the first time. Eight species are cleptoparasites; three are considered to be pseudoparasitoid,. Available literature data are considered. The number of ovarioles is 6 (3 per ovary) in most sphecids (including pseudoparasitoids), but 4 in most Oxybelus, and 8 in all cleptoparasites. It is hypothesized that the reduced number of ovarioles in Oxybelus is an adaptation to their prey-carrying mechanism (transporting the prey impaled on the sting). The increased number of ovarioles in cleptoparasites probably increases the number of eggs that a female can deposits both during her lifetime and within a given short time period. This is probably an adaptation to the spatiotemporally limited resource of suitable host nests. The number of mature oocytes increases from nonparasitic to cleptoparasitic to pseudoparasitoid species. Also, parasitic sphecids tend to have smaller oocytes than nonparasitic species, which, however, is only ambiguously corroborated by the present study. Our observations agree well with the literature data. and remarkable similarities in the general pattern in ovariole and oocyte numbers could he detected, which were explained accordingly as adaptations to parental investment strategies.

Variable Hessian fly (Diptera: Cecidomyiidae) populations in cereal production systems in eastern Washington

Abstract: A 3 yr study in a semiarid wheat production region of eastern Washington quantified Hessian fly, Mayetiola destructor (Say), populations in cereal production systems using on-farm replicated plots. The systems were as follows: reduced-tillage soft white winter wheat (SWW) (Triticum aestivum L.)-summer fallow rotation, no-till soft white spring wheat (SWS)-chemical fallow rotation, continuous no-till hard red spring wheat (HRS), and no-till HRS-no-till spring barley (SB) (Hordeum vulgare L.) rotation. This study also quantified natural mortality of fly populations in the spring cereal plots, identified hymenopterous parasitoids of the fly, and determined the biotype composition of the fly population at the research site. From 1998 to 2000, tiller infestations in no-till HRS and SWS plots (4.5-13.1%) increased to levels (15.6-47.5%) equivalent to or above the economic injury level of 13-20% for spring-infested tillers. The SB (cultivar Baronesse) in this study was resistant to Hessian fly. Fly infestations were non-existent or low on SWW in 1998 and 1999, but were higher in spring 2000 (27.6% infested tillers). Fly mortality (eggs to larvae) in HRS and SWS plots averaged 88.5 to 91.7% in 1999 and 77.7 to 87.9% in 2000, yet survival was sufficient to account for moderate to high populations in spring wheats. Ten hymenopterous parasitoid adults (seven Homoporus destructor (Say), two Eupelmus alynii French, and one Pediobius epigonus Walker) emerged from field collected puparia in 1999. The biotype composition of the fly population was 58% GP, 17% E, 14% F, 10% G, and 1% N. The high percentage of GP indicates that the currently deployed resistance gene H3 is effective against this population, but its effectiveness will likely diminish over time as frequencies of biotypes E and G, which are virulent to H3, increase in populations.

Annual displacement of soil in nest tumuli of alkali bees (Nomia melanderi)(Hymenoptera: Apiformes) across a Washington landscape

Abstract: Thousands of bee species nest in the ground, sometimes gregariously, digging central tunnels whose excavated soil is pushed to the surface as tumuli. To quantify tumulus production across a landscape, nesting female alkali bees (Nomia melanderi) were censused for the 155 km 2 Touchet Valley of southeastern Washington, where nest sites of alkali bees are managed to pollinate alfalfa seed fields. Across this landscape in 2001. an estimated 9.1 million nesting females collectively brought 87,500 kg (96 tons) of soil to the surface in their tumuli, much of which is subsequently eroded away by wind or rain. At this rate, the oldest populated nest site would have cumulatively lost four cm to surface subsidence as a result of the past half century's nesting activity. Bees are probably minor agents of biogeomorphology and bioturbation except where nesting females are concentrated in long-lived populous aggregations.

African fideliini: Genus Fidelia Friese (Hymenoptera: Apoidea: Megachilidae: Fideliinae)

Abstract: The tribe Fideliini comprises thirteen species in two genera, Fidelia Friese and Neofidelia Moure and Michener. Fidelia includes four subgenera, Fidelia, Parafidelia Brauns, Fideliana Michener, and Fideliopsis Engel (new status), with three, two, two, and five species. All are southern African, except for Fidelia (Fideliana) ulrikei Warncke from Morocco. Neofidelia has two South American species. Three new species of Fidelia (Fideliopsis) have been described: Fidelia fasciata, F borearipa, and F hessei; and lectotypes are designated for F braunsiana Friese, F aliceae Cockerell, F paradoxa Friese, and F friesei Brauns. A key to the species of Fidelia is provided, and for each species a diagnosis is included.