Observations on the biology and anatomy of Curtonotidae (Diptera: Schizophora)

New information concerning the biology and anatomy of Cyrtona spp. and Curtonotum quinquevittatum is given. During the hot, dry season the latter species leaves its warthog burrow refuges at night. Cyrtona spp. rest in densely shaded humid habitats during the same season, dispersing in the cooler seasons. Postabdominal sclerites and internal anatomy of the male abdomen are described for both genera. A suggested ground plan of the Ephydroidea is outlined.     

Inventory of Sarcophaginae (Diptera: Sarcophagidae) for the Humid Chaco,a poorly surveyed ecoregion of South America

ABSTRACT

Sarcophaginae is a large subfamily of sarcophagid flies (Diptera: Calyptratae: Oestroidea: Sarcophagidae) which have diverse habits, mainly sarcosaprophagous, and have forensic and sanitary importance. This is the first work that analyzes the fauna of Sarcophaginae exclusively in the Humid Chaco ecoregion where diversity of flies has scarcely been studied. This inventory was based on: a) samplings at different locations in the province of Chaco, Argentina, and in the state of Mato Grosso do Sul, Brazil; b) examination of entomological collections and c) bibliographic records. Sixty-two species of Sarcophaginae flies are included in this paper, of which 31 species are recorded for the first time in the Humid Chaco ecoregion. Ten species are new records for Argentina, two for Brazil and three for Paraguay. Lepidodexia (Neophytodes) lindneri Townsend, 1931, Lepidodexia (Notochaeta) adelina Mulieri, Schaefer, Duré and González, 2018, Lepidodexia (Pachygraphomima) lenti Lopes, 1980, Oxysarcodexia berthet Dufek and Mulieri, 2017, Oxysarcodexia ibera Dufek and Mulieri, 2017 and Retrocitomyia paraguayensis Lopes, 1985 are registered as endemic species of the Humid Chaco ecoregion. Species with forensically and sanitary importance are listed. Some comments on species distribution previously published in catalogues are provided.     

Field behavior and seasonal activity of the rodent bot fly, Cuterebra tenebrosa, central Washington (Diptera: Cuterebridae)

Behavior and activity of the rodent bot fly, Cuterebra tenebrosa Coquillett, was studied at a natural aggregation site in central Washington. Daily flight activity extended from 1700 hr to 2030 hr (PDT) beginning in mid - July of 1970 and 1971. The peak of flight activity, in August, was followed by a decline in activity through September. Male flies aggregated on the vertical faces of basalt cliffs, where they awaited females. Daily activity reached a peak at temperatures of 30 – 35 C. Eggs were laid in rock crevices without regard to the proximity of Neotoma wood rat hosts. Developing fly pupae were found in litter in wood rat tunnels in basalt cliffs.     

Nasal botflies of migrating wildebeest from western Zambia

Summary

A migratory population of wildebeest (Connochaetes taurinus) in Liuwa Plain National Park in the Western Province of Zambia was sampled for nasal bots (Diptera: Oestridae: Oestrinae) during 1975–78. Infestations from 32 antelope included Gedoelstia spp. (two species), Oestrus aureoargentatus and O. variolosus. A total of 1913 second and third instar larvae was recorded from the sinuses and nasal septa with individual parasite loads varying from 4 to 144 bots. No obvious pathogenicity was attributable to these oestrids, all four species of which were judged to be multivoltine in this habitat. The significance of this voltinism in relation to the migratory course of the wildebeest is discussed together with a consideration of parasite densities and the potential threat of myiasis to domestic livestock in the area.     

Blow flies (Diptera, Calliphoridae) of Idaho: an annotated checklist

A total of 33 species of blow flies (Diptera: Calliphoridae) are recorded from Idaho. They include 1 species each of Cochliomyia, Phormia, Protophormia, Trypocalliphora, Cyanus, Cynomya, and Melanodexia ; 12 species of Protocalliphora ; 5 species of Lucilia ; 6 species of Calliphora ; and 3 species of Pollenia . Other calliphorid species that may also occur in the state include 5 species of Protocalliphora and 3 species of Calliphora . Known distribution, periods of activity, abundance within the state, and biological notes are provided.     

Prey choices and foraging efficiency of recently fledged California Gulls at Mono Lake, California

We studied the foraging biology of recently fledged California Gulls ( Larus californicus ) at Mono Lake during August-September 1991. We made behavioral observations to collect information on the relative proportions of different prey types in the diet of these birds and took plankton tows to determine the relative abundance of each prey in the water column. These data show that alkali flies ( Ephydra hians ) were the primary constituent of the diet and that they were eaten at a much higher rate than one would expect based on their abundance. We also determined the number of feeding attempts and successful captures made during each behavioral observation. From these, we calculated the bird's feeding efficiencies on emergent adult alkali flies and on all other prey types combined. We found that foraging efficiencies on emergent flies were very high and significantly greater than those obtained on other prey types. These results suggest that flies were actively sought in preference to the alternative prey type, brine shrimp ( Artemia monica ), presumably because they are easier to capture and of greater nutritional value.     

On the life-habits and developmental stages of Nidomyia cana Papp (Diptera,Borboropsidae)

Eggs, second and third instar larvae of the enigmatic species Nidomyia cana, which was discovered most recently from the nests of raptorial birds in southern Hungary, are described. Both egg and larvae show peculiarities among the so-called heleomyzoid flies. Larvae were found in wet vegetable material (mostly pieces of poplar bark) of a buzzard nest and their shape is of a saprophagous type. Females are macro-oviparous, with a maximum of 15 to 17 eggs laid in one batch. Adults live mostly on the surface the of the nest, they copulate there, and they find shelter in the nest itself. No direct contact with adults or nestlings within the nest was observed. It is suggested that overwintering occurs as pupae (pharate adults) underground, beneath the nest. However, if N. cana lives exclusively in the nests of raptors, adults would have difficulties in finding a new nest, and it is probable that they are transferred to new nests attached to the birds.     

Food spectrum analysis of the Asian toad,Duttaphrynus melanostictus (Schneider, 1799) (Anura: Bufonidae), from Timor Island,Wallacea

The Asian toad, Duttaphrynus melanostictus (Schneider, 1799), is widespread throughout tropical Asia and very abundant where it occurs. It was relatively recently introduced to Timor, the second largest island in the biogeographic region called Wallacea. Timor Island shows an exceptionally high level of endemism in a wide range of faunal groups and there are concerns that D. melanostictus may have a negative impact on this diversity, including vertebrates, through direct predation. To evaluate the impact the diet of D. melanostictus might have on the local fauna, gut contents of 83 preserved toad specimens from five habitat types in Timor-Leste, a country occupying the eastern half of Timor Island, were examined. We identified 5581 prey items, comprising the following animal groups: annelids; snails and slugs; spiders and harvestmen; woodlice; millipedes and centipedes; grasshoppers, crickets and earwigs; termites; thrips and true bugs; beetles; ants; hymenopterans other than ants; true flies; butterflies; unidentified insects; and insect larvae. Small eusocial insects (ants and termites) constituted the major part of the diet (61.6% and 23.4%, respectively). No vertebrate prey was recorded. Prey item composition did not differ between habitats. The wide prey spectrum well indicates that D. melanostictus is a generalist invertebrate feeder, as other studies, from regions where this species occurs naturally, have already shown. Although the Asian toad seems to not generally prey on vertebrates, vertebrate species that are morphologically similar to invertebrates in their overall appearance may be consumed. Hence, a negative effect on some taxa (e.g. blindsnakes) may be possible. We also present some limited data on intestinal parasites occurring in D. melanostictus.     

Studies in European ant-decapitating flies (Diptera: Phoridae): ant alarm pheromone as host finding cue in Pseudacteon brevicauda,a parasite of Myrmica rubra (Formicidae: Myrmicinae)

Pseudacteon brevicauda Schmitz parasitizes Myrmica rubra in the Middle Rhine region in Germany. Female flies are attracted to disturbed ant colonies, where they attack Myrmica workers for oviposition. We experimented with different body parts of the ants, with dissected mandibular glands, and with synthetic gland constituents to locate the source of the fly attractant and the chemical basis of the signal. The attracting kairomone originates from the mandibular glands, which are used by Myrmica ants in alarm communication. Among the gland constituents, the ketones 3-octanone and 3-nonanone attracted and alerted the parasitic flies. The alcohol 3-octanol did not attract flies over long distance but it released an alerting response over short distance. A comparison of the chemical compositions of mandibular glands between ant species, focusing on the bioactive compounds, can explain both host specificity of P. brevicauda and the extension of the host spectrum to the (chemically similar) Myrmica scabrinodis.     

Remarkable waxing, waning, and wandering of populations of Mimulus guttatus : an unexpected example of global warming

Experimental sets of Mimulus cardinalis and M. lewisii plants were (1) exposed to pollinators and (2) shielded from pollinators at study sties in Red Butte Canyon and Big Cottonwood Canyon, Wasatch Mountains, Utah. The exposed plants produced 1,535 seedlings and the shielded plants only 1. Clearly, seed production is dependent upon cross-pollination. A few syrphid flies were observed visiting the flowers but no hummingbirds or bumble bees, although the latter two have been reported as the main pollinators of M. cardinalis and M. lewisii , respectively. No interspecific hybrids were produced even though the species are fully interfertile, indicating that pollinators are faithful to their species or that different parts of their bodies pick up and carry pollen to the two different species.     

Distribution of shore bugs and shore flies at Sylvan Springs, Yellowstone National Park

Three species of shore bugs (Hemiptera: Saldidae) and 10 species of brine flies (Diptera: Ephydridae) were collected at Sylvan Springs (Wyoming section of Yellowstone National Park, USA), an area containing both acid and alkaline thermal springs. The fauna consists of both widespread (e.g., shore bugs Saldula comatula Parshley and Saldula explanata [Uhler] and shore flies Atissa litoralis [Cole] and Scatella stagnalis [Fallén]) and Yellowstone Park–endemic species (e.g., Saldula nr. arenicola and the shore fly Ephydra thermophila Cresson). The ratio of adults to nymphs of the numerically dominant shore bug Saldula nr. arenicola is higher along heated margins (11–12:1) than along near-ambient-temperature margins (0.6–2:1) of a thermal channel at Sylvan Springs; this may reflect differences in food availability, osmoregularity, thermal tolerance, predation, or other factors. Shore flies include species typical of acid ( E. thermophila ) and alkaline ( Paracoenia bisetosa [Coquillett] and Paracoenia turbida [Curran]) springs.     

The early larval instars of Lucilia sericata and Lucilia cuprina (Diptera,Calliphoridae): myiasis blowflies of Africa and Australia

Lucilia cuprina and Lucilia sericata are probably the two most important sheep myiasis flies in the southern hemisphere. This paper describes and illustrates structural features that enable reliable specific identification of the first and second instars of these species of be made.     

Studies on the tolerance of aquatic insects to low oxygen concentrations

Acute, short - term (96 - hour) tests were conducted to determine the relative sensitivity of low oxygen concentrations to 20 species of aquatic insects. In addition, the longer - term effects of low oxygen levels on the survival, molting, growth, and emergence of 21 species were studied. This paper encompasses work conducted at the University of Montana Biological Station from 1968 to 1970 and at the University of Utah from 1966 to 1972. An evaluation of the average minimum dissolved - oxygen requirements of the different groups of aquatic insects tested indicates that the mayflies are the most sensitive, that the stoneflies are next, and that the caddis flies, freshwater shrimp, true flies, and damselflies follow, in that order. While two species of mayfly could tolerate as low a dissolved-oxygen concentration as 3.3 mg/1 for 10 days, a level of 4.6 mg/1 was required for 50-percent survival at 30 days. Fifty percent of the true flies and damselflies tested were able to survive at levels ranging from 2.2 to 2.8 mg/1 for periods ranging from 20 to 92 days.       

Protandric simultaneous hermaphroditism and sex ratio in Lysmata nayaritensis Wicksten, 2000 (Decapoda: Caridea)

Caridean shrimps display a wide variety of sexual systems, including the newly discovered protandric simultaneous hermaphroditism. Protandric simultaneous hermaphroditism is known only from seven species of Lysmata, and it is not clear if this condition is fixed within the genus or if Lysmata includes species that are simply protandric or gonochoric (with separate sexes). This study uses anatomical data, aquarium experiments, and field observations to demonstrate that Lysmata nayaritensis is another protandric simultaneous hermaphrodite. It is shown that, despite occurring in the tropics, this species fits into the “crowd” species category, with high densities in the field and that the field sex ratio is highly male‐biased. Information on the sex allocation and sexual system of more species needs to be examined before these observations can be put into a comparative context within the genus.     

Bristlecone pine and Clark's Nutcracker: probable interaction in the White Mountains, California

Many bristlecone pines in the White Mountains, California, are members of multistem clumps. We propose that these clumps have arisen by multiple germinations from seed caches of Clark’s Nutcracker, as occurs in several other pine species. The commonness of nutcrackers and their caching of singleleaf pinyon seeds in the study area provide supporting evidence. Other vertebrates appear unlikely to be responsible for the stem clumps. Seed burial may be required to establish regeneration on these adverse sites where bristlecone pine attains great longevity.        

Differential attraction of calyptrate flies (Diptera) to faeces

Adult flies may visit faeces to lay eggs or larvae, to feed, or to drink, in dry weather. Within the group of calyptrate flies without meral bristles (Muscoidea), species that breed in faeces show a significantly greater tendency to visit it than those species that breed in other media. Oestroidea (with meral bristles) do not show this tendency, ecological confirmation of the anatomical fact that calyptrates fall into at least two distinct natural groupings. Visiting faeces to drink seems unimportant for muscoids. The dung of semi-wild browsing cattle is visited by few calyptrate fly species and is only attractive for a short time.     

Effects of defoliation on reproduction of a toxic range plant, Zigadenus paniculatus

Zigadenus paniculatus is a toxic plant common on sagebrush foothills at middle elevations in the western United States. Plants produce several racemes from a single stalk. Flowering commences at the base of each raceme and proceeds upwards. The terminal raceme begins blooming first and is followed by lower racemes in sequential order. Flowers are markedly protandrous and incapable of autogamy. Observations do not support the idea that apomixis is a viable reproductive strategy. Plants are mostly self-incompatible; a few seeds were produced from geitonogamous hand pollinations. The pollen/ovule ratio was high, also suggesting outcrossing as the predominant mode of sexual reproduction. A self-incompatibility mechanism may have evolved because the movements of syrphid flies on the inflorescence render protandry alone insufficient to prevent some selfing. The probable presence of toxic substances in the pollen and nectar appears to have reduced the number of potential pollinator species but increased the flower constancy of those species capable of utilizing the floral rewards.