Body temperatures of Namib Desert tenebrionid beetles: their relationship in laboratory and field

Abstract The body temperatures of six apterous species of Namib Desert tenebrionid beetles were measured continuously with indwelling thermocouples under laboratory conditions and in the field. The range of body temperatures selected was within the upper half of their 'tolerated range', which we defined as the temperatures lying between measured critical thermal maximum and critical thermal minimum. In the field, individuals also maintained their body temperatures within the upper half of the 'tolerated range'. These beetles maintained higher body temperatures than those recorded for any other ectothermic insect. Three of the six species maintained lower body temperatures in the field than they selected in the laboratory. The other three species showed no significant difference between field and laboratory body temperatures. We conclude that these beetles are not forced by biotic or abiotic factors to adopt thermal niches which present them with physiological difficulties.     

Response of the sandfly Lutzomyia longipalpis to an oviposition pheromone associated with conspecific eggs

Response of female Lutzomyia longipalpis Lutz & Neiva (Diptera: Psychodidae) to an oviposition attractant and/or stimulant associated with conspecific eggs was investigated in the laboratory. Females of two populations laid significantly higher mean number of eggs on sites with 160 eggs already present than on bare control sites. This response was lost when eggs placed on test sites were previously washed in organic solvents and distilled water. Age of eggs placed on test sites, 1-6 days after being laid, did not seem to affect the oviposition response of the females. Comparing effects of different numbers of eggs, positive responses were obtained when 80, 160 or 320 eggs were placed on test sites. No significant differences between mean egg numbers laid on test sites and controls were detected when batches of only 20 or 40 eggs were used.     

Potential interspecific competition and host specificity: hispine beetles on Heliconia

Abstract. 1. Adults of rolled-leaf hispine beetles (Chrysomelidae, Coleoptera) spend their lives in the scrolls formed by immature leaves of Heliconia (Heli-coniaceae, Monocotyledonae) in Tropical America. As many as eight hispine species can intermingle in the host scrolls at a single site. Scrolls of single host species are invariably occupied by adults of more than one hispine species, and as many as five species can simultaneously occupy one scroll.
2. I made virgin scrolls, which had never contained any insects, by growing leaves under the cover of plastic bags.
3. Thirty-seven combinations of single hispine and Heliconia species were experimentally created in the virgin scrolls, at two sites and in two seasons, in Costa Rica. Combinations included all abundant host species at the sites.
4. All beetles left all leaves of the twenty-eight unnatural beetle—host combinations, within 24 h. On the other hand, none of the nine natural combinations was completely abandoned within the experimental period.
5. Thus, host specificity is not broader in the absence of similar hispine species that might be competitors, and interspecies competition does not affect this obvious aspect of resource utilization for these phytophagous insects.     

A GENETIC ANALYSIS OF SYMPATRIC SUBPOPULATIONS OF THE SIBLING SPECIES LITTORINA SAXATILIS (OLIVI) AND LITTORINA ARCANA HANNAFORD ELLIS

A detailed analysis of shell characteristics (four parameters)and allozyme allele frequencies (eight to nine polymorphic loci)of sympatric Littorina saxatilis and Littorina arcana subpopulationsfrom Filey Brigg on the east coast of England supports theiridentification as closely related but separate species. Oneenzyme system, esterase-2, was nearly species diagnostic. Resultswere generally comparable with an earlier study of the two speciesfrom East Lothian, Scotland. Littorina saxatilis was again foundto be more variable than L. arcana. (Received 14 December 1983;     

A Non-destructive Sampling Technique for Spodoptera mauritia (Boisduval) (Lepidoptera: Noctuidae) and Herpetogramma licarsisalis (Walker) (Lepidoptera: Pyralidae) in Turf

Experiments were conducted using chemical irritants to develop a non-destructive sampling technique for pests of high quality turf and lawn. POW detergent at a concentration of 35 mL in 3.5 L of water applied to an area of 1,600 cm² was the most effective for sampling Spodoptera mauritia and Herpetogramma licarsisalis and resulted in 84% of S. mauritia larvae surfacing within 4 min of application. No larvae surfaced after 4 min. Kendon pyrethrin SF applied at a concentration of 0.46 mL in 3.5 L of water resulted in similar numbers of larvae surfacing relative to 35 mL POW detergent. However, larvae took up to 20 min to surface. Formaldehyde and the pyrethroid, Mavrik® AF did not cause S. mauritia and H. licarsisalis larvae to surface.     

Coxsackie virus in Southern California; isolation of a strain from stools of a patient

Thirty-three stool specimens from 29 patients were examined for Coxsackie virus by the inoculation of suckling mice. Such a virus, designated "California I," was obtained from two stool specimens collected on successive days from a patient with so-called nonparalytic poliomyelitis. Neutralizing antibodies for the California I strain of Coxsackie virus could not be demonstrated in serum obtained from the patient early in the illness, but were present in convalescent serum.Serum from the patient's daughter, who previously had had a similar illness, neutralized the strain of virus isolated from the father. In pathologic examination of the skeletal muscles of mice infected with the California I virus, lesions typical of those produced by Coxsackie virus, group A, were noted. California I strain of the virus was not neutralized by immune serum prepared from several other strains of Coxsackie virus.