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Chironomidae larvae constituted the largest proportion of benthic invertebrates collected from 99 rivers stretching from northern Labrador (latitude 58°N) to northern parts of Ellesmere Island (82°N). We describe 92 species of Chironomidae (mainly larval forms) providing new descriptions, a revision for the adult female of Parametriocnemus boreoalpinus Gowin et Thienemann, a possible new genus (larval form only), and 9 larval forms that may represent a new species. In addition, new geographical distribution records are specified for 1 Nearctic species, 6 species in Canada, 10 for Labrador, and 17 for Nunavut. This work contributes to Environment Canada’s International Polar Year output (2007-2009).

An opportunistic survey for Epiophlebia laidlawi larvae was carried out within five districts in Western and Central Bhutan from 2012 to 2014. The study recorded a total of 21 individuals from five districts and also recorded F0, F3 and F8 instars larvae for the first time in Bhutan. The study adds December and February as possible months to record F0 instars within its range. The record of E. laidlawi from Bumthang District extends its range to the eastern most part of the Himalayas, and it also extends its range from Chhukha District to its southern most range within Bhutan. A record from Punakha District fills the gap between the previous and current record of E. laidlawi from Wangchhu basin in Western Bhutan and Drangmechhu basin spanning central and eastern Bhutan with Punatshangchhu basin in between. The record from Trongsa District emphasises the importance of the study area as E. laidlawi’s habitat. The extent range of E. laidlawi within Bhutan is now extended to six districts, viz., Haa, Thimphu, Chhukha, Punakha, Trongsa and Bumthang.

This study examined ammonia excretion at different life stages (eggs, larvae and juveniles) in silver catfish (Rhamdia quelen) and determined the influence of fasting time on ammonia excretion. Eggs and larvae were collected from incubators at different times after fecundation and placed in chambers. Juveniles were separated into two weight classes (2-50 g and 150-320 g) and placed in individual chambers after feeding. Water was collected from each chamber to determine ammonia excretion. Ammonia excretion by the eggs was low, but when hatching began approximately 28h after fecundation, excretion increased until 48h after fecundation. In fasting silver catfish juveniles, there was a significant negative correlation between ammonia excretion and weight. Moreover, ammonia excretion decreased significantly after 12 and 48h of fasting (compared to 6h fasting) in the smallest and largest specimens, respectively. Consequently, during incubation of silver catfish eggs, water renovation must be increased at hatching time to avoid a build-up in the concentration of ammonia. In addition, as ammonia excretion in this species increases after feeding, feed must be discontinued when ammonia levels in the tanks are high to avoid a further increase of this metabolite and consequent mortality of silver catfish.Verificou-se a excreção de amônia em diferentes estágios de vida (ovos, larvas e juvenis) e determinou-se a influência do tempo de jejum na excreção de amônia no jundiá, Rhamdia quelen. Ovos e larvas foram coletados das incubadoras em diferentes tempos após a fecundação e colocados em recipientes. Juvenis foram separados em duas classes de peso (2-50 e 150-320 g) e após a alimentação foram colocados em recipientes individuais. As águas foram coletadas de cada recipiente para determinação da excreção de amônia. A excreção de amônia pelos ovos foi baixa, mas iniciada a eclosão – 28h após a fecundação, ela aumentou até as 48h. Nos juvenis em jejum, houve significativa correlação negativa entre a excreção de amônia e o peso. Além disso, a excreção de amônia diminuiu significativamente após 12 e 48h de jejum nos espécimes menores e maiores, respectivamente. Portanto, a renovação da água deve ser aumentada no momento da eclosão dos ovos de jundiá para evitar aumento da concentração de amônia. Como nessa espécie a excreção de amônia aumenta após a alimentação, quando os níveis nos tanques forem elevados a alimentação deve ser suspensa para evitar aumento adicional deste metabólito e mortalidade.

Larval therapy is a technique that allows the useof larva of some diptera species on chronicwounds or localized infected focuses, in order topromote the affected tissue restoration. Thetreatment velocity and efficacy, with almost nohealthy tissue loses during the process, havemade larval therapy (sometimes calledbiosurgery) a viable alternative for healingwounds associated with entities as diabetic foot,venous ulcers, cutaneous chronic ulcers andburns, and some benign tumors, abscesses andosteomyelitis.Although modern medicine has been, in manycases, reticent on the application of this kind oftherapies, events as antibiotic resistance andalterations in cicatrization process in chronicwounds, have modified the respective initialpoint of view of many doctors.

Predation on larvae and put a of the2g 268-276 (1998) p p gypsy moth, Lymantria dispar (L.) was studied in a leading-edge population in West Virginia. In 8 thinned and 8 uncut stands rates of survival of larvae and pupae were monitored in 3 types of exclosures placed at 3 heights in the forest strata. The abundance of small mammals was measured within each of these stands using pitfall traps. 37% of larvae and25% of pupae were killed by predators over the 3 d of observations each year. Thinning did not influence the proportion of larvae or pupae killed. Survival of larvae and pupae on the ground was significantly lower than that found on tree boles or in the foliage. Differences in survival among exclosure types indicated that invertebrates were the major predators of larvae, and small mammals were the major predators of pupae. [ABSTRACT FROM AUTHOR]