The North American representatives of seven species groups in the genus Pardosa are reviewed and are found to have the following distribution: (1) the atrata group, represented by the widespread nearctic species P. fuscula (Thorell), which may or may not be conspecific with P. atrata (Thorell) of the Palaearctic; (2) the cubana group, represented by P. cubana Bryant of the Caribbean area; (3) the ferruginea group, represented by P. beringianasp.n. from Alaska and Yukon Territory; (4) the moesta group, represented by the widespread nearctic P. moesta Banks; (5) the monticola group, represented by the holarctic P. palustris (Linnaeus); (6) the saltuaria group, represented by the holarctic P. hyperborea (Thorell) and the nearctic P. californica Keyserling; (7) the solituda group, represented by the nearctic P. solituda Levi and Levi, found only in the high Rockies.

The primary follicles of all 291 laboratory-reared Simulium arcticum Malloch females provided with only sucrose and water did not develop beyond stage II. This was true for flies derived from field-collected eggs, larvae, or pupae, and for laboratory-reared larvae that received either standard, concentrated, or unsupplemented river water diets. Conversely, all 59 females that digested a meal of cattle blood had follicles at stage IV by 85 h and stage V (mature eggs) by 109 h post-engorgement. Simulium arcticum populations from the Athabasca and Crowsnest River were thus characterized by obligate anautogeny and gonotrophic concordance. Most non-blood-fed females were dissected and examined when 4–19 days old. The presence or absence of a meconium, quantity of fat body, and other internal features were compared in young and old non-blood-fed females.

Dissections of flies caught attacking cattle and flying over the Athabasca River (14 June through 11 September 1974) revealed two large peaks of nulliparous females and two peaks of parous females. In both cases, peak numbers of nullipars preceded the peaks in pars. A small third cohort emerged in late August, and some nullipars were collected over the river on all sampling dates.

Around cattle, nullipars had two prominent, but brief, peaks, followed by two subsequent prolonged periods when pars were most abundant. Parity of captured females was typical of the expected seasonal pattern of parity for an anautogenous species and corroborated our previous determination of obligate anautogeny of laboratory-reared females.

Females examined for parity status were categorized as being teneral, blood-fed, gravid/ovipositing, or parasitized with a mermithid parasite (Isomermis spp.). Dissection of 2414 flies caught over the river revealed little difference in the infection rates of males and females throughout the season. Mermithids occurred primarily in nulliparous flies of the first generation and retarded the development of the reproductive organs in both sexes. Parasitism did not prevent nulliparous females from mating, nor feeding on carbohydrate or blood. A blood meal actually seemed required for maturation of the mermithid parasite. Blood-engorged females with mermithids were collected both around cattle and flying over the Athabasca River. When parasitized females with digested blood meals joined swarms of ovipositing females, mermithids were returned to the river. Nearly all flies harbored just one worm; of the 1435 parous females examined for parity, only 1 had a small mermithid. By killing flies from which they exited, the worms prevented females from taking a second blood meal.

Although flies were killed by exit of the mermithid, this parasite is ineffective against the major pest species, Simulium arcticum Malloch, because it does not prevent parasitized females from seeking and taking a blood meal and thereby harassing cattle. However, in years when nearly 50% of the emerged adults are parasitized (like 1974), this mermithid may be a principal factor regulating the population density of the S. arcticum population in subsequent years.

A discussion is presented about specimens that are morphologically intermediate between Nephrotoma ferruginea (Fab.) and N. suturalis suturalis (Loew). The specimens came from far outside the present ranges of these two species, namely Kerrville, Texas. It is concluded that the specimens might represent a population of hybrids. It is further estimated that the withdrawal of the parental species from central Texas could possibly have occurred a thousand years ago or earlier.

Subspeciation in the circumpolar Nephrotoma lundbecki is discussed for a population from south of the Laurentide Ice Sheet, described here as N.l. alexanderi. For 18 nearctic Nephrotoma species new distribution records are presented, mainly from the northern Nearctic, adding considerably to our knowledge of the distribution of these species. Included is the second nearctic record of the palaearctic species Nephrotoma cornicina (L.).

Rhagionids were studied principally by capturing adults in emergence traps at Southington (1979) and in Malaise traps at Hamden (1980–1983) and Guilford, CT (1983–1985). Most captures of Chrysopilus rotundipennis Loew, C. thoracicus (Fabr.), Rhagio mystaceus (Say), and Symphoromyia hirta Johnson occurred during a 2- to 5-week period. Mean capture dates for sexes differed significantly in only a few cases. Based on percentage of total captured, S. hirta and R. mystaceus ranked first and second at Hamden whereas C. rotundipennis and S. hirta had these respective ranks at Guilford. The sex ratio of C. ornatus (Say) adults in emergence traps did not depart significantly from 1.0, but most rhagionids captured in Malaise traps had skewed sex ratios. Based on percentage and quotient of similarity, faunas at Hamden and Guilford shared many species, but relative abundances of species common at one or both sites were very different. In this study, we found 14 rhagionid species, including 4 not previously recorded from Connecticut. A total of 16 species are now recorded from the state.

Greenhouse and field trials were done to determine the potential of Heterorhabditis heliothidis (Khan, Brooks and Hirschmann) Poinar (NC19 strain), an undescribed Heterorhabditis sp. (NC447 strain), and Steinernema feltiae Filipjev (A32−6 strain) to control British Columbia populations of black vine weevil (Otiorhyncus sulcatus Fab.) and strawberry root weevil (O. ovatus L.). An outdoor application of H. heliothidis applied at rates of 500 and 5000 nematodes per litre of soil gave significantly better control of black vine weevil larvae on potted, lodgepole pine trees (Pinus contorta Dougl.) than did a diazinon drench. Under greenhouse conditions Heterorhabditis sp. NC447 was the most effective nematode of the three tested against O. ovatus on potted, Douglas-fir seedlings (Pseudotsuga menziesii (Mirb.) Franco) and S. feltiae the least effective, at all dose rates tested. A field trial using H. heliothidis against O. ovatus in a forest nursery did not provide a significant degree of weevil control. This lack of control is attributed to the average outdoor temperature (11 °C) during the treatment period, which was below the nematode’s optimum temperature range, and the higher-than-average rainfall.

Parasitism of the Colorado potato beetle, Leptinotarsa decemlineata (Say), by Edovum puttleri Grissell, an exotic egg parasitoid, was studied in relation to the age of host eggs, the age of adult, female parasitoids, and temperature. Parasitism was greater in eggs ≤2 days old than in eggs older than 2 days. Eggs older than 2 days were killed primarily by probing and consequent desiccation. The percentage of eggs killed by probing was positively correlated with host age and negatively correlated with percentage parasitism. Total mortality of eggs from parasitism and probing did not differ among age classes. Following a 3-day preoviposition period, parasitism and probing increased with an increase in the age of females, peaked when adults were ca. 13 days old, and subsequently declined. Parasitism and probing were influenced by temperature: at 15 °C, no parasitism or probing was observed; above 15 °C, mortality from parasitism and probing increased with an increase in temperature up to 30 °C; above 30 °C, the number of eggs that were parasitized and probed decreased with an increase in temperature.

This paper reviews the occurrence of the genus Chlorochroa Stål in Canada. It is shown that 10 species occur in this country, namely C. belfragii (Stål), C. faceta (Say), C. congrua Uhler, C. granulosa (Uhler), C. ligata (Say), C. opuntiae Esselbaugh, C. persimilis Horvath, C. rossiana Buxton and Thomas, C. uhleri (Stål), and C. viridicata (Walker). Chlorochroa sayi (Stål) does not occur in Canada. The published records of C. sayi as a pest of agricultural crops and ornamentals in Canada refer to C. uhleri.

Water suspensions of the entomogenous nematode, Steinernema feltiae Filipjev (“All” strain), were applied to the soil of caged microplot stands of canola, Brassica napus L. cv. Tower, colonized by overwintering adults of the crucifer flea beetle, Phyllotreta cruciferae (Goeze), at the rate of about 1 × 106 infective juveniles per 0.8 m2 soil surface. Single treatments, which were applied before and after the colonization, did not affect the flea beetle adults or their progeny as evidenced by the number of new generation adults that subsequently emerged from the soil. Bioassays with wax moth larvae, Galleria melonella (Linn.), showed that the infectivity of nematodes in the soil declined sharply within 6 days of treatment. High concentrations of the herbicide Treflan®, with which the soil was treated, did not affect the infectivity of the nematodes. Under the conditions of the test, S. feltiae appeared to have no potential as a biological control agent for the crucifer flea beetle.

Anoplius tenuicornis (Tournier) is a holarctic species with a broad distribution both in Europe (Wolf 1967) and North America (Wasbauer and Kimsey 1985). Despite the widespread occurrence of the species, individuals are not frequently encountered, so it is not surprising that biological information on it has not been available for North America and very little for Europe. Richards and Hamm (1939) gave two fragmentary reports of some significance on A. tenuicornis in England, reported as A. piliventris (Morawitz). In one case, cocoons of the wasp were found in dead thistle stems. In the other, an old burrow of Ectemnius continuus (Fabricius) (Sphecidae) (reported as Solenius) in rotten wood contained a series of wasp cocoons and fragments of clubionid spiders, the presumed prey.