RESUMEN
Abstract The bee genus Rhynostelis Moure & Urban, a cleptoparasite taxon restricted to the Neotropical Region, was previously known from a single species. In the present work, the genus is revised, with three species recognized, of which two are described as new: Rhynostelis chrysogaster sp. nov. and Rhynostelis plesiognatha sp. nov. from Panamá and Brazil, respectively. Misidentification of the type species, Rhynostelis multiplicata (Smith, 1879), in previous works is pointed out and discussed. Diagnosis, illustrations and an identification key for the three recognized species are also provided.
RESUMEN
ABSTRACT The new genus †Burmasphex is proposed for two fossil species, †Burmasphex sulcatus sp. nov. and †Burmasphex pilosus sp. nov., described from Myanmar Cretaceous amber. It exhibits many plesiomorphic features in relation to the extant Apoidea and is here provisionally allocated in the extinct family †Angarosphecidae.
RESUMEN
ABSTRACT A review of bee species used as hosts of mutillid wasps in the Neotropical region is presented. Three new confirmed host records are provided for the mutillid species Hoplomutilla biplagiata Mickel, 1939, Pappognatha limes Mickel, 1939, and Tallium aracati Casal, 1962. Two potential host records are provided for Euspinolia rufula Mickel, 1938 and Lophomutilla inca Fritz and Pagliano, 1993. Additionally, Mutilla hoplitiformis Strand, 1909, is transferred to the genus Darditilla. Correlations between host nesting habits and female mutillid morphology are discussed. Lastly, all known confirmed and potential host records in the Neotropical region are compiled.
RESUMEN
ABSTRACT Two new species of the stingless bee genus Schwarziana from Brazil are described and illustrated. Schwarziana bocainensis sp. nov. is described from Serra da Bocaina, in São Paulo, and S. chapadensis sp. nov. is described from Chapada dos Veadeiros, in Goiás. An identification key to workers of the known species of Schwarziana is provided.
RESUMEN
Our study on the intracellular distribution of B12 and DBC on a normal and injured liver following the administration of these labelled test materials show that (1) with increasing interval, the pattern of distribution of these two closely related compounds in the various cellular fractions will simulate each other; (2) chromatography of B12 and DBC obtained from soluble fractions exhibited nearly identical Rf values; both findings lend support to our belief that the conversion of vitamin B12 to 5,6 dimethylbenzimidazole cobamide coenzyme took place; (3) in an injured liver, the initial uptake of either B12 or DBC activity is significantly different from the uptake, in almost all cellular fractions, of an intact liver; however, with prolonged interval, the pattern of distribution of B12 and DBC among the individual fractions will eventually be identical. (Summary)