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The South American rice miner, Hydrellia wirthi Korytkowski (Diptera: Ephydridae), a recently discovered, invasive pest of rice, Oryza sativa L., is reported from southeastern United States (Louisiana and Texas). A detailed description and diagnosis with illustrations and photographs are provided to facilitate identification, along with descriptions of its damage as a miner in rice whorls, stems, and leaves. The localities where this invasive species has been found in Louisiana and Texas are provided.

Two species of Discomyza Meigen occur in the New World, one, D. u-signata Cresson, naturally and the other, D. maculipennis (Wiedemann), apparently as an introduction. These species are revised and their malacophagous breeding habits are documented. The species treatments include the first detailed descriptions and illustrations of structures from the male terminalia, lectotype designations for Notiphila maculipennis Wiedemann and its New World synonym (D. balioptera Loew), as well as phylogenetic and biogeographic information, including maps. Although congeners, these two species are apparently not closely related, and their occurrence in the New World is independent of each other. D. maculipennis has a biogeographic connection with the Orient, and D. u-signata is linked with a group of Afrotropical species, D. eritrea Cresson specifically.

The genus Tronamyia is described in the tribe Lipochaetini (subfamily Gymnomyzinae) with Asmeringa lindsleyi Sturtevant & Wheeler (new combination) as its type species. The type species had previously been listed as an unplaced species in the tribe Atissini (subfamily Hydrelliinae). In a phylogenetic analysis of the tribe Lipochaetini, Tronamyia is the sister group of Lipochaeta Coquillett, a genus that also occurs along maritime beaches or inland saline or alkaline playas of the New World.

We tested the effects of three vegetation management strategies for constructed treatment wetlands on adult shore-fly (Diptera: Ephydridae) successional occurrence and emergence in southern California. Before flooding with effluent from a nearby wastewater treatment plant, eight 0.1-ha research cells were randomly assigned to (1) control cells which were burned to reduce the above ground plant biomass, (2) scoured cells which were burned and then scoured with a rock bucket attached to a backhoe, and (3) hummock cells which were burned and scoured before the placement of earthen mounds that provided shallow areas to concentrate vegetation growth within a small area. Emergence traps and pan traps were used simultaneously to capture adult Ephydridae from July 1998 to September 1999. Twenty-eight species of ephydrids from 23 genera were collected; the cumulative number of shore-fly taxa reached its maximum at 135 d after flooding, and exhibited a hyperbolic pattern over time. Only Brachydeutera sturtevanti Wirth differed significantly in its successional mean occurrence in pan traps among vegetation management treatments, being virtually absent from hummocked cells during 1998 but becoming one of the numerically dominant taxa in all treatments by August 1999. Both emergence and pan traps in the hummocked cells captured significantly fewer B. sturtevanti and Notiphila spp. in the other treatments during 1998, but there were no differences in numbers collected among the vegetation management treatments during 1999. Vegetation management significantly slowed the appearance of Ephydridae in constructed treatment wetlands, but only a short period of time (

Brachydeutera sturtevanti Wirth is a shore fly found commonly in a variety of lentic habitats, including ephemeral pools, in the American Southwest and northern Mexico. We conducted field studies and laboratory rearings to elucidate the morphology and trophic ecology of this colonizer species important to newly flooded habitats such as constructed wetlands. The larvae are generally hyponeustic, suspended from the water surface by hydrofuge hairs on the posterior spiracles. All instars exhibit extremely versatile feeding strategies by collecting or scraping algae and detritus from solid substrates, or by bringing their mouthparts to the water surface and creating a vortex to initiate filter feeding. The mouthhooks are modified to form dorsoventrally-flattened plates lined with stout projections that facilitate the versatile larval feeding. The incubation period under laboratory conditions (20–22°C) was 1–4 d; the three stadia lasted 3–5 d each while the pupal period was 6–8 d. The results of a col...

Fifteen species of shore flies, nearly doubling the number of known fauna, are reported from the Galapagos Islands. Of the 15 species, all but 2 are widespread in the Neotropics and apparently arrived on the Galapagos as introductions, which were probably independent events. The 2 apparent endemics, Philygria galapagensis Wirth and Scatella galapagensis Curran, may have speciated on these islands. The shore-fly fauna is disharmonic biogeographically, with only 11 of 20 tribes being represented. Ephydra gilvipes Coquillett (new synonym) is conspecific with E. chilensis Macquart, the senior synonym. A lectotype for Paralimna decipiens Loew is designated.

A multiple discriminant functions analysis of Scatella stagnalis (Diptera: Ephydridae) from 40 localities in North America showed that only a small portion of the interlocality variation can be accounted for by the geographic positions of the localities. It was hypothesized that the observed variation was due to some combination of local selective pressures and non-selective factors. The data suggest that gene flow is of little importance in this species. Analysis of variance indicated significant interpopulational differences in all 12 characters measured for both males and females, except for the length of the 3rd antennal segment in males. Further analysis showed the females to be larger than the males with respect to all characters. The variational patterns found in males were only partially paralleled in females. This may be a reflection of the varying patterns of sexual dimorphism or it might indicate that males and females are being subjected to somewhat different selective pressures. The analysis indicated that the recognition of geographic races (subspecies) would be inappropriate.

The life histories of Notiphila aenigma Cresson and N. solita Walker, 2 common species of Ephydridae occurring in cattail marshes, were studied in Montana and Ohio, respectively. Larvae of both species develop in oxygen-poor bottom sediments where they ingest detritus and associated saprophytic microorganisms. Larvae obtain oxygen by periodically tapping intercellular air spaces in Typha rootlets by use of their sharply pointed spiracular spines. Notiphila aenigma apparently is univoltine, whereas N. solita is at least bivoltine. Both species overwinter as nearly mature larvae. Puparia are always attached to cattail rootlets via the spiracular spines. The eggs, 3 larval instars, and puparia are described and illustrated. Possible ecological isolating mechanisms that permit co-existence of 4 species of cattail marsh-inhabiting Ephydridae in Montana are discussed.

Adults of Paryda quadrituberculata , distributed in North America east of the Rocky Mountains, occur most abundantly in mud- and sand-shore habitats where they feed upon stranded motile, benthic diatoms. Adults use the labellar canalicular processes for scooping and fanning diatoms into the mouth, or prestomum, whereas larvae use their rapidly protracting and retracting mouthhooks to dislodge and move diatoms close to the mouth into which they are sucked by cibarial action. Adults exhibit a definite activity rhythm consisting of searching/feeding, cleaning, and resting with intervening periods of copulation and oviposition during the daylight period followed by “roosting,” or sheltering upon vegetation or prominent objects at twilight. Heavy rain during daylight elicits “roosting” activity. Eggs are laid on emergent objects in conterminal masses of 2–16 and covered by a thin, uniform, green or yellow-green fecal layer, which turns white in old egg masses. Sparsity of emergent objects on mud flats frequently leads to extensive, multiparental encrustations of egg masses. The incubation period lasts 2–5 days. Serial longitudinal sections of 24 second- and 3rd-instar larvae revealed guts packed with diatoms. The larval stadia total 10–23 days and the puparial phase lasts 5–9 days (or much longer in overwintering forms). Pupation occurs in mud with the postanal elongation bent upward and the bifurcated posterior tracheospiracular siphons projecting slightly above the mud surface. At moderate latitudes, both puparia and adults overwinter, but winter collecting indicates that the adult is the main overwintering stage. The adults typically shelter deep in shoreline grass and sedge hummocks. Some gravid females overwinter and adults in general feed and fly during still, sunlit winter days when the air temperature is above 3.3°C. The primary mortality agents are believed to be parasitic Hymenoptera, weather, and shore birds. Urolepis rufipes (Pteromalidae), Hexacola spp. (Cynipidae), Asobara sp. (Braconidae) were reared from puparia. Aggregation of larvae in isolated, drying mud pools was frequently observed, and it is surmised that this aggregation facilitates parasitization. The egg, 3 larval instars, and puparium are described and illustrated.

Paracoenia bisetosa (Coquillett) is a shore fly common throughout most of the Nearctic Region. It is encountered in a number of habitats including hot and cold mineral springs and in a variety of freshwater to moderately high alkaline and saline environments. Adults were found from early March to early November, and immatures from April to October. Adults overwinter. Adults and immatures were, respectively, most prevalent on and within limnic vegetational debris. Mating and oviposition took place on vegetational mats, the female inserting the eggs slightly into it. Eggs were laid in clumps of 18 to 57. Abiotic mortality factors included prolonged periods of rain, cold, or both. Predators included dolichopodid and ephydrid flies, Odonata, various Hemiptera and Coleoptera, and shore birds. After a developmental period of two to four days, larva hatched by rasping the chorion with their mouthhooks. The first stadium lasted one to three days, the second, two to four days, and the third, three to seven days. The combined prepupal-pupal period was five to eight days. The egg to adult period ranged from 13-26 days. P. bisetosa probably averages five to six generations per year. The egg, three instars, and puparium are described and illustrated.

Two species of brine fly (Diptera: Ephydridae), Paracoenia calida Mathis, which is endemic, and Ephydra goedeni Wirth, which is known from hot springs in several U.S. states, occur in high densities in the thermal (source temp. = 54°C), saline (22 parts per thousand [ppt] salinity) waters of Wilbur Hot Springs, Colusa County, Calif. Both populations are multicohort and multivoltine (based on the year-round presence of all life stages), yet their spatial distributions within the Wilbur Hot Springs thermal effluent are highly segregated. These result from species-specific differences in life history traits and larval physiological tolerances. For example, by ovipositing near the hot spring source, having larval metabolic rates that are independent of high temperatures, and using atmospheric oxygen for larval respiration, P. calida inhabits all but the hottest portions of the Wilbur Hot Springs effluent. In contrast, E. goedeni adults oviposit in cooler, more oxygen-rich pools than those occupied by P. calida . Larvae of E. goedeni are most abundant in these cooler (yet decidedly thermal) waters, perhaps because their metabolic rates increase at high temperatures and they use dissolved oxygen for respiration. However, unlike those of P. calida , larvae of E. goedeni can tolerate water salinities that differ from those at Wilbur Hot Springs. A comparison of physiological traits indicates that P. calida is more highly adapted for existence in thermal saline waters than E. goedeni ; specialization for life under such severe and rare habitat conditions may account for the endemic distribution of P. calida .

In an earlier paper (Berg, 1949) 32 species of insects intimately associated with plants of the genus Potamogeton in Michigan were listed. Species of plants and areas in which they were collected were recorded. The insects, including Diptera of 17 species, were dismissed with a few general remarks concerning aquatic adaptations, modes of hibernation, and injuries inflicted upon host plants. Biology and morphology of immature stages of nine species of Chironomidae reared from Potamogeton are discussed in another paper (Berg, 1950). Similar data regarding eight acalyptrate species will be presented here. Parasitic Hymenoptera reared from puparia of Hydrellia in this investigation represent nine species, seven of which appear to be new. Publication of data on the biology of these interesting insects will be deferred until they are described and specific names become available.

In northeastern Ohio and northwestern Montana, adults of Dichaeta caudata (Fallen), a common and widely distributed species of the subfamily Notiphilinae, are found most abundantly in sedge marshes containing open areas of exposed mud that have surface accumulations of moist, decaying vegetation. Adults can live 10–60 days in the laboratory, and females have a preoviposition period of 5–15 days. Eggs are deposited throughout the summer and there are no obvious interruptions between generations. The incubation period lasts 1–2 days. Larvae feed within decaying plant materials and probably ingest mostly microorganisms, particularly bacteria and yeasts. Larval development requires 7–17 days. Although the puparium has a long caudal breathing tube and is welladapted for floating, puparia are formed in somewhat drier situations than those preferred by the larvae. The combined prepupal and pupal periods last 6–8 days, and the entire life cycle can be completed in 19–44 days under laboratory conditions (21–25°C). Overwintering apparently takes place as adults in diapause. The egg, 3 larval instars, and puparium are described and illustrated.

Dimecoenia fuscifemur , n. sp., from the shores of Virginia and Georgia, is described, and 2 previously known species are included with it in the morphologically distinct typical group of the genus. A key to species, notes on distribution, and data on the postabdomen of both sexes are presented.

“Brine flies” or “salt flies” of the genus Ephydra Fallen are often very abundant in coastal salt marshes, salt and alkaline lakes and ponds, and around thermal and mineral springs. From a detailed study of the male genitalia, 16 species of Ephydra are recognized in North America. These are classified in 3 subgenera: Ephydra s. str., with 6 species in the riparia group and 7 species in the glauca group; HALEPHYDRA , new subgenus with 1 species; and Hydropyrus Cresson with 2 species. Characters of the male genitalia of each species are described and illustrated, brief diagnoses are given of external features, and a key is presented for the recognition of all taxa. The known biology and distribution are summarized. Ephydra goedeni , n. sp. is described from hot springs in Oregon and nearby states; E. packardi , new name is proposed for E. halophila Packard (not von Heyden), and E. currani , new name for E. salina Curran (not von Heyden); and the correct application of other specific names is indicated from a study of the respective types.

Detailed study of the male genitalia of the flies of the genus Brachydeutera of the world makes possible more accurate identification of the six previously known species. These species are redescribed and the following eight species are described as new: africana, brunnea, congolensis, hardyi, neotropica, pauliani, stuckenbergi, and sturtevanti. A key is given for their identification, figures of the male genitalia are presented, and new distribution records are listed.

Continuous quantitative sampling of neustonic insect populations presents some difficulties. Many insects of the neuston are not attracted to light traps or are attracted only during certain types of weather. Some neustonic insects are active both day and night, but some species are either diurnal or nocturnal in their activity. In addition, the nocturnal habits of a large majority of neustonic insects are unknown. Conceivably, some of these problems could be overcome by systematic use of special floating traps. One of these employs a detergent to trap the insects. This trap, devised by Grigarick (1959), consists of a detergent solution contained in a shallow pan held within a wooden frame float. The float is anchored on the corners with dowels and can be equipped with a rain shield. Grigarick designed the device to trap adults of Hydrellia griseola (Fallen) (Diptera: Ephydridae), which alight upon and skate over the water surface. Flies attempting to settle upon the trap solution sink, probably because of the destruction of their tarsal hydrofuge oils and the decrease of the surface tension by the detergent.