Primer registro de la abeja colectora de óleo Centris (Odontoxys) melanochlaena Smith, 1874 (Hymenoptera, Apidae) en Nicaragua

Se presenta el primer reporte de la abeja colectora de óleo Centris (Odontoxys) melanochlaena Smith, 1874 en Nicaragua. Esta especie se distribuye en varios países de Centroamérica y México, siendo este el primer reporte en el occidente de Nicaragua. Este registro contribuye al conocimiento del rango de distribución de esta especie, así como también incrementa la lista de especies de abejas nativas de Nicaragua.

The first report of the oil-collecting bee Centris (Odontoxys) melanochlaena Smith, 1874 in Nicaragua is presented. This species occurs in several Central American countries and Mexico, being this the first record from western Nicaragua. This record contributes to the knowledge of the distribution range of this species, as well as increases the list of native bees occurring in Nicaragua.

The bee fauna (Hymenoptera, Apoidea) in Cerrado and Cerrado-Amazon Rainforest transition sites in Tocantins state, Northern Region of Brazil / A fauna de abelhas (Hymenoptera, Apoidea) em áreas de Cerrado e de transição Cerrado-Floresta Amazônica no estado do Tocantins, Região Norte do Brasil

Abstract: Two sites located in Tocantins State, Brazil, were selected for the bee's community survey. One of them was mostly covered by Cerrado vegetation and the other one is located in the Cerrado-Amazon Rainforest ecotone. Five expeditions were performed in each site throughout a 12-month period, between 2019 and 2020. The total of 771 bee specimens were collected and distributed into four families. Apidae presented the greatest species abundance and richness, it was followed by Halictidae, Megachilidae and Andrenidae, respectively. Trigona pallens (Fabricius) (Apidae) was the species presenting the greatest abundance in both sites, it totaled 118 specimens, which corresponded to 26.9% of the total abundance of individuals belonging to tribe Meliponini. In general, the community presented several species with few individuals and few species with many individuals. Bee collections were performed by using three different methodologies, among them one finds sampling based on the entomological net method, which allowed collecting the largest number of both individuals and species in comparison to the other used methods. Based on the frequency and abundance classes, only few species were classified as very frequent (VF) and very abundant (VA) in both sites based on the frequency and abundance classes. Most species were constant (W) in both regions, and there was a small number of dominant species (D); moreover, more than 70% of the sampled species were considered accidental (Z). According to the present study, either Cerrado or Cerrado-Amazon Rainforest studied sites presented higher species richness than other sites in these biomes sampled in Brazil.

Resumo: Duas áreas localizadas no Estado do Tocantins, Brasil foram selecionadas para o levantamento da comunidade de abelhas, uma área com vegetação predominante de Cerrado e outra em ecótono Cerrado-Amazônia. Durante cinco expedições em cada área em um período de 12 meses, entre os anos de 2019 e 2020 foram coletados 771 espécimes de abelhas, distribuídas em quatro famílias: Apidae, com a maior abundância e riqueza de espécies, seguida de Halictidae, Megachilidae e Andrenidae. Trigona pallens (Fabricius) (Apidae) foi a espécie com maior abundância em ambas as áreas, totalizando 118 espécimes, o que correspondeu a 26,9% da abundância total de indivíduos da tribo Meliponini. De um modo geral, a comunidade apresentou muitas espécies com poucos indivíduos e poucas espécies com muitos indivíduos. A metodologia de coleta com uso de rede entomológica permitiu a coleta do maior número de indivíduos e de espécies em relação a outros três métodos utilizados. Em ambas as áreas, poucas espécies foram classificadas como muito frequentes (MF) e muito abundantes (MA), de acordo com as classes de frequência e de abundância. Também para ambas as áreas, grande parte das espécies foram constantes (W) e um baixo número de espécies dominantes (D), com mais de 70% delas consideradas acidentais (Z). O presente estudo revelou que tanto o Cerrado como a área de transição Cerrado-Floresta Amazônica apresentou alta riqueza de espécies em comparação com outras áreas destes biomas amostradas no Brasil.

Synthesis of b(1 ? 3) and b(1 ? 6) galactooligosaccharides from lactose and whey using a recombinant b-galactosidase from Pantoea anthophila

BACKGROUND: Milk whey, a byproduct of the dairy industry has a negative environmental impact, can be used as a raw material for added-value compounds such as galactooligosaccharides (GOS) synthesis by bgalactosidases. RESULTS: B-gal42 from Pantoea anthophila strain isolated from tejuino belonging to the glycosyl hydrolase family GH42, was overexpressed in Escherichia coli and used for GOS synthesis from lactose or milk whey. Crude cell-free enzyme extracts exhibited high stability; they were employed for GOS synthesis reactions. In reactions with 400 g/L lactose, the maximum GOS yield was 40% (w/w) measured by HPAEC-PAD, corresponding to 86% of conversion. This enzyme had a strong predilection to form GOS with b(1 ? 6) and b (1 ? 3) galactosyl linkages. Comparing GOS synthesis between milk whey and pure lactose, both of them at 300 g/L, these two substrates gave rise to a yield of 38% (60% of lactose conversion) with the same product profile determined by HPAEC-PAD. CONCLUSIONS: B-gal42 can be used on whey (a cheap lactose source) to produce added value products such as galactooligosaccharides.

A new species of Andinopanurgus (Hymenoptera: Andrenidae) from high elevations in southern Peru / Una especie nueva de Andinopanurgus (Hymenoptera: Andrenidae) de las grandes alturas del sur de Perú

We describe and figure a distinctive new species of the bee genus Andinopanurgus Gonzalez and Engel (Andrenidae, Protandrenini) from Apurímac and Cusco in southern Peru. Andinopanurgus vargasllosai Gonzalez and Alvarado, n. sp., occurs at elevations above 4000 m in the Central Andes and is the second species of this genus in Peru. The new species possesses terga with semi-translucent distal margins, a unique feature among Andinopanurgus, and it combines morphological features of the two species groups previously recognized in the genus. To facilitate its recognition, we provide an updated key to species of Andinopanurgus.

Describimos e ilustramos una especie nueva del género Andinopanurgus Gonzalez y Engel (Andrenidae, Protandrenini) procedentes de Apurímac y Cusco, al sur de Perú. Andinopanurgus vargasllosai Gonzalez y Alvarado, n. sp., se encuentra en alturas superiores a los 4000 m en los Andes centrales y es la segunda especie del género registrada para el Perú. La especie nueva posee tergos metasomales con las márgenes distales semi-translúcidas, una característica única dentro de Andinopanurgus, y combina características morfológicas de los dos grupos de especies hasta ahora reconocidos en el género. Con el fin de facilitar la identificación, presentamos una clave actualizada para las especies de Andinopanurgus.