WorldCat Identities

Praz, Christophe

Works: 19 works in 26 publications in 3 languages and 48 library holdings
Genres: Classification 
Roles: Other, Author
Classifications: QL568.M4, 551.57
Publication Timeline
Most widely held works by Christophe Praz
Mature larvae and nesting biologies of bees currently assigned to the Osmiini (Apoidea, Megachilidae) by Jerome G Rozen( )

2 editions published in 2016 in English and held by 9 WorldCat member libraries worldwide

The purpose of this study is to describe the mature larvae of all taxa of the tribe Osmiini (Megachilidae) whose postdefecating larvae have been collected and are available. The hope is that data uncovered will eventually lead to a better understanding of the interrelationships of included taxa and of their anatomies, behaviors, and ecologies (i.e., their natural histories). The species included are representatives of the following taxa: Ashmeadiella, Atoposmia, Chelostoma, Heriades, Hoplitis, and Osmia (Hoplosmia). We also include recently described larval representatives of Haetosmia and Ochreriades. Because of its large size and diversity, the genus Osmia alone (with the exception of the subgenus Hoplosmia) is allocated to a separate future investigation. Larvae of the tribe share many features with one another and also with other members of the Megachilidae. Anatomical structures of larval Osmiini whereby they can be differentiated from other megachilids were not identified. However, most (though not all) members of the tribe fall into one of three main subgroups on the basis of: (1) body form, (2) presence or absence of middorsal, intersegmental tubercles on basal abdominal segments 1-5, and (3) the depth of intersegmental constrictions. In the process of gathering specimens the authors uncovered new information concerning nesting biology with respect to nest location and structure and to cocoon structure and function. These data were derived from the authors' own field studies as well as from specimens and field data collected through the years by others
Etat de la biodiversité en Suisse en 2014 : une analyse scientifique( Book )

1 edition published in 2015 in French and held by 8 WorldCat member libraries worldwide

Allgemeiner Teil, Gattungen, Apis, Bombus = Partie générale, genres, Apis, Bombus by Felix Amiet( Book )

1 edition published in 2017 in German and held by 6 WorldCat member libraries worldwide

Unraveling hydrometeor mixtures in polarimetric radar measurements by Nikola Besic( )

2 editions published in 2018 in English and held by 4 WorldCat member libraries worldwide

Floral specialization in solitary bees a case study of the osmiine bees by Christophe J Praz( )

3 editions published in 2008 in English and held by 4 WorldCat member libraries worldwide

Nesting biology, flower preferences, and larval morphology of the little-known Old World bee Ochreriades fasciatus (Apoidea, Megachilidae, Megachilinae) by Jerome G Rozen( Book )

3 editions published in 2015 in English and held by 3 WorldCat member libraries worldwide

Herein we present information on the nesting behavior of Ochreriades fasciatus (Friese) found occupying beetle galleries in dead trunks and branches of certain trees and shrubs in Israel. We also describe the pre- and postdefecating larvae thereby making known the mature larva for this uncommon Old World genus. Females of O. fasciatus build linear nests in existing burrows in dead wood; depending on the length of the burrow, 1-5 cells are placed in one nest. The cell partitions are made of hardened mud, while the nest plug consists of pebbles fixed together with mud. Ochreriades fasciatus is oligolectic on Lamiaceae and probably strongly associated with the two related genera Ballota and Moluccella. It is hoped that information concerning its nesting biology, host-plant relationships, as well as larval development and anatomy will eventually prove valuable in determining the phylogenetic position of this genus relative to other megachiline bees
Identification of blowing snow particles in images from a Multi-Angle Snowflake Camera by Mathieu Schaer( )

1 edition published in 2020 in English and held by 2 WorldCat member libraries worldwide

Solid hydrometeor classification and riming degree estimation from pictures collected with a Multi-Angle Snowflake Camera by Christophe J Praz( )

1 edition published in 2017 in English and held by 2 WorldCat member libraries worldwide

Nests, floral preferences, and immatures of the bee Haetosmia vechti (Hymenoptera, Megachilidae, Osmiini) by Ariella Gotlieb( Book )

2 editions published in 2014 in English and held by 2 WorldCat member libraries worldwide

Herein we describe the nests (including structure, closure, orientation, and depth of cells) of the bee Haetosmia vechti Peters found nesting in Rehovot, Israel. The nesting biology of H. vechti mirrors the ancestral nesting biology within the Osmia group of the Osmiini. Nests in sandy soil consist of an excavated burrow, ending below in a small cluster of vertical cells. The cells possess firm walls of masticated leaf pulp of Centaurea procurrens Spreng. and Heliotropium suaveolens M. Bieb., and are covered with pebbles and sand grains. The last larval instar and pupa of Haetosmia vechti are described, as is its cocoon. The immature stages exhibit the basic features of megachilid bees, but tend to have a thinner body vestiture compared to other studied taxa. In addition, we report new information on and review published accounts concerning the pollen collecting behavior of the genus Haetosmia Popov, which contains three species. Pollen taken from scopal hairs of 68 females collected at 17 sites in Turkestan, Morocco, Israel, and the United Arab Emirates was identified as originating solely from Heliotropium L. (Boraginaceae), which strongly suggests that all three Haetosmia species are narrowly oligolectic on this plant genus. In females of all three species, the second segment of the labial palpus is densely covered with rather long, apically curved and capitate bristles, an adaptation to collect Heliotropium pollen from anthers that are hidden inside the narrow corolla tube. Similar pollen-harvesting bristles specifically adapted to exploit flowers of Heliotropium seem to have evolved independently a number of times on different continents, in bees of four families
European red list of bees( )

1 edition published in 2014 in English and held by 1 WorldCat member library worldwide

The European Red List is a review of the conservation status of European species according to IUCN regional Red Listing guidelines. It identifies those species that are threatened with extinction at the regional level - in order that appropriate conservation action can be taken to improve their status. This publication summarises results for all Europe's native species of bees (1,965 species). 9.2% of species are threatened with extinction at the European level due to habitat loss as a result of agriculture intensification (e.g., changes in agricultural practices including the use of pesticides and fertilisers), urban development, increased frequency of fires and climate change. The European Red List was compiled by IUCN's Global Species Programme and the European Union Representative Office with support from the STEP project (www.STEP-project.onet) and it is the product of a service contract with the European Commission. It is available online at and
Nests, petal usage, floral preferences, and immatures of Osmia (Ozbekosmia) avosetta (Megachilidae, Megachilinae, Osmiini), including biological comparisons with other osmiine bees( )

1 edition published in 2010 in English and held by 1 WorldCat member library worldwide

Herein we describe the nests (including construction, closure, orientation, and depth of cells) of the bee Osmia (Ozbekosmia) avosetta Warncke found nesting near Antalya, Turkey, and Sepidan, Iran. Cells are unusual in that they are lined by two layers of colorful flower petals that sandwich a thin middle layer of mud. Analyses of pollen taken from scopal hairs of specimens from the Turkish site were identified as solely from Onobrychis viciifolia Scop. (Fabaceae) whereas those from the Iranian site were from a related plant, Hedysarum elymaiticum Boiss. and Hausskn. These facts coupled with analyses of scopal pollen from 11 other sites in Turkey, Jordan, and Syria strongly suggest that this bee is oligolectic with respect to the plant tribe Hedysareae. The egg and last larval instar of Osmia avosetta are described. The presence of an egg taken from a cell and provisionally identified as belonging to Sapyga pulcherrima Morawitz suggests that this cleptoparasite may have this bee as one of its hosts. In addition, we report new information on and review published accounts concerning the use of whole petals or large petal pieces in the construction of cell walls of osmiine bees. Only Osmia (Ozbekosmia) avosetta and species of Osmia (Tergosmia) have three-layered cell walls with the middle layer made of mud. Recorded also are the similarities and differences exhibited in pollen and petal preferences and nest characteristics of species in these two related subgenera
Regeneration of a dominant ectomycorrhizal tree species in an African lowland rainforest: the roles of light, density-dependence and distance to adults by Christophe J Praz( Book )

1 edition published in 2003 in English and held by 1 WorldCat member library worldwide

DNA barcoding of the potter wasp genus Eumenes Latreille, 1802 (Hymenoptera: Vespidae: Eumeninae) in Switzerland by Rainer Neumeyer( )

1 edition published in 2015 in German and held by 1 WorldCat member library worldwide

Nursing protects honeybee larvae from secondary metabolites of pollen( )

1 edition published in 2018 in English and held by 1 WorldCat member library worldwide

Abstract : The pollen of many plants contains toxic secondary compounds, sometimes in concentrations higher than those found in the flowers or leaves. The ecological significance of these compounds remains unclear, and their impact on bees is largely unexplored. Here, we studied the impact of pyrrolizidine alkaloids (PAs) found in the pollen of Echium vulgare on honeybee adults and larvae. Echimidine, a PA present in E. vulgare pollen, was isolated and added to the honeybee diets in order to perform toxicity bioassays. While adult bees showed relatively high tolerance to PAs, larvae were much more sensitive. In contrast to other bees, the honeybee larval diet typically contains only traces of pollen and consists predominantly of hypopharyngeal and mandibular secretions produced by nurse bees, which feed on large quantities of pollen-containing bee bread. We quantified the transfer of PAs to nursing secretions produced by bees that had previously consumed bee bread supplemented with PAs. The PA concentration in these secretions was reduced by three orders of magnitude as compared to the PA content in the nurse diet and was well below the toxicity threshold for larvae. Our results suggest that larval nursing protects honeybee larvae from the toxic effect of secondary metabolites of pollen
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Audience level: 0.89 (from 0.66 for Mature lar ... to 1.00 for Nests, pet ...)

Alternative Names
Praz, C.

Praz, C. J.

Praz, Christophe.

English (19)

French (4)

German (3)