Jakub Straka

Charles University in Prague | CUNI · Department of Zoology (PF)

Taxonomy and nomenclature of the genus Stylops Kirby, 1802 (Strepsiptera) have been understood differently in different parts of world for a long time. Largest differences came from erroneous concept of host specialization of individual species. For this reason, we re-evaluated taxonomy and nomenclature in all Stylops species based on distances of...

Host specialization is an important ecological characteristic of parasitic species. The identification of the parasitic strategy of the genus Stylops (Strepsiptera; Stylopidae) is, however, ambiguous. According to the number of recognized species based on existing taxonomy, highly specialized and supergeneralistic species exist in this genus. Our r...

1. Animal lifespan is constrained by ecology and physiology. The latter has been studied under controlled conditions, but little is known about determinants of lifespan under natural conditions. 2. We studied the relationships between length of adult life, magnitude of foraging activity, and environmental abiotic conditions in two bee species: a p...

Two new species of Strepsiptera from the genus Zethus Fabricius, 1804 (Hymenoptera: Vespidae) are described. Although the stylopisation of the genus Zethus has been known for almost a century, we provide the first description of its strepsipteran parasites. Zethus brasiliensis fuscatus R. Bohart & Stange, 1965 is parasitised by Eupathocera zethisp....

A new genus and species of Strepsiptera, Chrysostylops australiensis Benda & Straka, gen. et sp. nov., is described. It represents the first record of the family Stylopidae from Australia. It was parasitising the bee species Chrysocolletes aureus Leijs & Hogendoorn, 2021 (Neopasiphaeinae). The diagnosis and description of the genus and species are...

Jan Macek, one of the leading personalities of the Czech hymenopterology, celebrated his 70th birthday in 2023. His entire professional career has been associated with the Department of Entomology at the National Museum in Prague (since 2023 officially the National Museum of the Czech Republic), where he worked as a curator of the Hymenoptera Colle...

We reconstruct the phylogeny of the most speciose genus of cuckoo bees, genus Nomada Scopoli, 1770, using 221 species from throughout its distribution, yet with a strong emphasis on the West Palearctic. For phylogenetic reconstruction, we sequenced ultraconserved elements, allowing robust phylogenetic estimates with both concatenation and coalescen...

The twisted‐winged parasite genus Stylops has a history of different species concepts with varying host specificity resulting in diverse species diversity estimates in different regions of the Holarctic. The adoption of a supergeneralist species concept in Europe, proposing synonymization of all Western Palaearctic Stylops species, did not facilita...

Pollinators play a crucial role in ecosystems globally, ensuring the seed production of most flowering plants. They are threatened by global changes and knowledge of their distribution at the national and continental levels is needed to implement efficient conservation actions, but this knowledge is still fragmented and/or difficult to access. As a...

A new species of Strepsiptera of the genus Paraxenos Saunders, 1872 (Xenidae) from the United Arab Emirates is described. It was recorded from the host species Bembix kohli Morice, 1897 and represents the first occurrence of Paraxenos from Bembix Fabricius, 1775 in the Afrotropical region. A detailed redescription of the female cephalothorax of Par...

An essential prerequisite to safeguard pollinator species is characterisation of the multifaceted diversity of crop pollinators and identification of the drivers of pollinator community changes across biogeographical gradients. The extent to which intensive agriculture is associated with the homogenisation of biological communities at large spatial...

Arrhenotoky is the typical mode of reproduction in Hymenoptera. Diploid females develop from fertilized eggs, whereas haploid males originate from unfertilized eggs. However, some taxa of Hymenoptera have evolved thelytoky, in which diploid females originate parthenogenetically from unfertilized diploid eggs. In contrast to some other hymenopteran...

In comparison to organisms parasitising vertebrates, parasites of arthropods are direly understudied despite their abundance, importance, and potential usefulness. Due to their close relationship and coevolution with the host, parasites can be used as tools allowing the inference of information on host life history, ecology, and past events the hos...

Anthropogenic drivers of bumblebee population decline are well-established, particularly in Europe and North America. Agriculturalizsation is associated with a loss of nesting sites, habitat fragmentation, agrochemical toxicity and nutritional stress; climate change is affecting population distribution, phenology, and voltinism, among other traits....

Two new species of Strepsiptera of the genus Xenos Rossi, 1793 (Xenidae) from the New World are described. Both are endoparasites of social wasps of the genus Mischocyttarus Saussure, 1853 (Vespidae: Mischocyttarini). Xenos bicolor Benda & Straka, sp. nov., parasitizes Mischocyttarus navajo Bequaert, 1933, Mischocyttarus flavitarsis (Saussure, 1854...

Human-induced environmental impacts on wildlife are widespread, causing major biodiversity losses. One major threat is agricultural intensification, typically characterised by large areas of monoculture, mechanical tillage, and the use of agrochemicals. Intensification leads to the fragmentation and loss of natural habitats, native vegetation, and...

Two new species of Strepsiptera of the genus Xenos Rossi, 1793 (Xenidae) from the New World are described. Both are endoparasites of social wasps of the genus Mischo-cyttarus Saussure, 1853 (Vespidae: Mischocyttarini). Xenos bicolor Benda & Straka, sp. nov., parasitizes Mischocyttarus navajo Bequaert, 1933, Mischocyttarus fl avitarsis (Saussure, 18...

Using RADSeq approaches, we uncovered potential loci associated with 5 environmental variables (land cover and climate) in two European bumblebee species (Bombus pascuorum and B. lapidarius).

In comparison to organisms parasitising vertebrates, parasites of arthropods are direly understudied despite their abundance, importance, and potential usefulness. Due to their close relationship and coevolution with the host, parasites can be used as tools allowing the inference of information on host life history, ecology, and past events the hos...

Despite recent advances in phylogenomics, the early evolution of the largest bee family, Apidae, remains uncertain, hindering efforts to understand the history of Apidae and establish a robust comparative framework. Confirming the position of Anthophorinae—a diverse, globally distributed lineage of apid bees—has been particularly problematic, with...

Despite recent advances in phylogenomics, the early evolution of the largest bee family, Apidae, remains uncertain, hindering efforts to understand the history of Apidae and establish a robust comparative framework. Confirming the position of Anthophorinae—a diverse, globally distributed lineage of apid bees—has been particularly problematic, with...

It is increasingly recognised that intraspecific variation in traits, such as morphology, behaviour, or diet is both ubiquitous and ecologically important. While many species of predators and herbivores are known to display high levels of between-individual diet variation, there is a lack of studies on pollinators. It is important to fill in this g...

Arrhenotoky is typical mode of reproduction for Hymenoptera – females originate from fertilized eggs, males from unfertilized eggs. However, some lineages of Hymenoptera have switched to thelytoky, where diploid females originate instead from unfertilized diploid eggs. In the contras with some other hymenopteran lineages, thelytoky is generally ver...

Abstract – Natural history of facultative social taxa is important for understanding the evolution of Eusociality. However, data for the social status of many species are missing. Social status of seven European Ceratina bees was studied in Cyprus. Multifemale nests were found in fve species of three diferent subgenera: C. (Euceratina) mandibularis...

The generic taxonomy and host specialization of Xenidae have been understood differently by previous authors. Although the recent generic classification has implied a specialization on the level of host families or subfamilies, the hypothesis that each xenid genus is specialized to a single host genus was also previously postulated. A critical eval...

Safeguarding crop pollination services requires the identification of the pollinator species involved and the provision of their ecological requirements at multiple spatial scales. However, the potential for agroecological intensification of pollinator-dependent crops by harnessing pollinator diversity is limited by our capacity to characterise the...

• Drastic reductions of insect diversity and abundance have been observed in highly fragmented agricultural landscapes of central Europe. Declines of pollinators may have detrimental effects on the reproduction of wild insect-pollinated plants as well as the yield of crops. In order to mitigate such impacts, sown flower strips on arable land within...

The mining bees (Andrenidae) are a major bee family of over 3000 described species with a nearly global distribution. They are a particularly significant component of northern temperate ecosystems and are critical pollinators in natural and agricultural settings. Despite their ecological and evolutionary significance, our knowledge of the evolution...

Societies of social Hymenoptera usually consist of groups of closely related females in which the dominant female(s) is specialized for reproduction and subordinate females care for immature offspring. Studying simple societies allows the identification of factors responsible for early stages of evolution of sociality. Here, we examined facultative...

Brood parasites (also known as cleptoparasites) represent a substantial fraction of global bee diversity. Rather than constructing their own nests, these species instead invade those of host bees to lay their eggs. Larvae then hatch and consume the food provisions intended for the host’s offspring. While this life history strategy has evolved numer...

It is increasingly recognised that intraspecific variation in traits, such as morphology, behaviour, or diet is both ubiquitous and ecologically important. While many species of predators and herbivores are known to display high levels of between-individual diet variation, there is a lack of studies on pollinators. It is important to fill in this g...

Drastic reductions of insect diversity and abundance are observed in the highly fragmented agricultural landscapes of central Europe. Declines of pollinators may have detrimental effects on the reproduction of wild insect-pollinated plants as well as the yield of crops. In order to mitigate such impacts, sown flower strips on arable land within Agr...

The study of wild bees has markedly increased in recent years due to their importance as pollinators of crops and wild plants, and this interest has been accentuated by increasing evidence of global declines in their abundance and species richness. Though best studied in Europe and North America, knowledge on the current state of wild bees is scarc...

Colletes hederae Schmidt & Westrich, 1993 is a cryptic bee species from the C. succinctus species-group. The previous occurrence and spreading of this species were predominantly in south-western Europe. To determine if the species was spreading in Slovak territory, Hedera helix was monitored from autumn 2015. The ivy-bee was first recorded in Slova...

Biparental care is very rare in insects, and it was well-documented in only one bee species to this date – Ceratina nigrolabiata. However, biparental care was only recently discovered in this species, and detailed description of natural history of this species is missing. Here, we describe the nesting cycle of C. nigrolabiata. Pairs of C. nigrolabi...

The precopulatory behaviour of the larviform females of Ripidius quadriceps Abeille de Perrin, 1872 is described. The calling posture of virgin females is documented. The cephalic morphology and microstructures are visualized using scanning electron microscopy, in particular the secretory pores in the cuticle of inflatable maxillary palps. An exhau...

Aculeate Hymenoptera have two modes of overwintering. In solitary species, adults usually do not emerge before winter and overwinter in their natal nests. In the majority of social species, adults activate before winter and only inseminated females perform overwintering. We examined the winter survival strategy in four species of small carpenter be...

Morocco is a well known hot-spot of biodiversity in the Mediterranean basin. While some taxa like vascular plants are relatively well recorded, important groups of pollinators like bees are still understudied. This article presents an updated checklist of the bee species of Morocco and includes a summary of global and regional distribution of each...

Morocco is a well known hot-spot of biodiversity in the Mediterranean basin. While some taxa like vascular plants are relatively well recorded, important groups of pollinators like bees are still understudied. This article presents an updated checklist of the bee species of Morocco and includes a summary of global and regional distribution of each...

Bees of the tribes Biastini, Neolarrini, and Townsendiellini are cleptoparasites in the subfamily Nomadinae (Hymenoptera, Apidae) and parasitize solitary bees. Understanding their phylogenetic relationships has proven difficult for many decades. Previous research yielded ambiguous results because of conflicting phylogenetic signals of larval and ad...

Parasitism is one of the most successful and ancient strategies. Due to the specialized lifestyle of parasites, they are usually affected by reductions and changes in their body plan in comparison with nonparasitic sister groups. Extreme environmental conditions may impose restraints on behavioural or physiological adaptations to a specific host an...

Many organisms are known to have wide distribution ranges, which cover large variability of ecological conditions. Therefore, natural history traits can differ throughout the distributional range, and, thus, studies on the natural history of traits from multiple areas of a single species are highly valuable. Ceratina cucurbitina is the most common...

Participants of the thirteenth Czech-Slovak Meeting on Hymenoptera carried out faunistic research in the Malé Karpaty Mountains (SW Slovakia). Occurrence of Symphyta, Aculeata and the selected Parasitica were examined in five localities during the vegetation season in 2017. On occasion they visited twelve additional localities in the Malé Karpaty M...

Parental care directed to adult offspring is uncommon in animals. Such parental care has been documented in Xylocopinae bees (Hymenoptera, Apidae). Moreover, some Ceratina bees (Xylocopinae) are known to feed mature siblings, and feeding of mature siblings is achieved by dwarf eldest daughters when mothers died. These daughters are intentionally ma...

Colonies of social Hymenoptera are usually groups of closely related females, in which the dominant female(s) is specialized for reproduction and subordinate females care for immature offspring. Kin selection is thought to be the main factor that supports social cohesion. We have discovered a simple society of the bee Ceratina chalybea with an aver...

Most bees collect pollen and nectar for their larvae, while some also collect other resources. We investigated the evolution of floral oil-collecting behaviour in the Apidae and the evolutionary effects of floral oils on host brood cells for cuckoo bees. Focusing on apid bee phylogeny, we reconstructed the evolution of floral oil collection by fema...

1. Maternal investment can be influenced by several factors, especially maternal quality and possibilities for future reproduction. Mass provisioning Hymenoptera are an excellent group for measuring maternal investment because mothers distribute food sources to each brood cell for each offspring separately. Generally in aculeate Hymenoptera, larger...

Letter from Portman (1) regarding our PNAS article about the biparental bee (2) is an excellent contextual addition to male behavior in bees because the male role in hymenopteran societies is generally overlooked (3) and discussion about it can improve scientific awareness. Portman (1) created a summarization of examples of male presence in nests....

Species of the genus Miscophus from Central, Northern, and Eastern Europe are reviewed and a new key to these species is presented. Miscophus cappadocicus de Beaumont, 1967 is given a new status of a valid species (described as a subspecies of Miscophus mavromoustakisi Andrade 1953). New synonyms for Miscophus albufeirae Andrade, 1952 are: Miscophu...

Significance Biparental care is a rare strategy of offspring protection in insects. We discovered a case of biparental care in bees, in Ceratina nigrolabiata . Benefits of biparental care were identified for both males and females; yet, we found that an extraordinarily high proportion of offspring were unrelated to guard males. This is because fema...

After the break-up of Gondwana dispersal of organisms between America, Australia and Africa became more complicated. One of the possible remaining paths led through Antarctica, that was not yet glaciated and it remained habitable for many organisms. This favourable climate made Antarctica an important migration corridor for organisms with good disp...

In Canada, the order Strepsiptera consists of 27 known species representing five families: Corioxenidae (1 species), Elenchidae (1 species), Halictophagidae (5 species), Stylopidae (15 species), and Xenidae (5 species). These totals represent an increase of 21 species since the 1979 assessment. Half of these species represent unpublished records re...

Most bees collect pollen and nectar for their larvae, while some also collect other resources. We investigated the evolution of floral oil-collecting behaviour in the Apidae and the evolutionary effects of floral oils on host brood cells for cuckoo bees. Focusing on apid bee phylogeny, we reconstructed the evolution of floral oil collection by fema...

Measurement of food consumed by larvae of progressive provisioning bees requires an experimental approach that marks the food sources appropriately. This paper aims to measure the amount of sugars and proteins consumed by a single bumblebee larva and to define, how the proportion between protein and sugar changes under stress conditions. We marked...

The apoid wasps have traditionally been regarded as a paraphyletic assemblage of four families (Ampulicidae, Crabronidae, Heterogynaidae and Sphecidae) that are closely related to the bees (Anthophila). The present study covers the three families of apoid wasps known to occur in Europe, i.e., the Ampulicidae, Crabronidae, and Sphecidae. DNA barcode...

Local changes in land use and climatic conditions provoke transformations of habitats and therefore, distribution changes of species in the landscape. Different insect groups are repeatedly used as indicators of local ecological conditions in biodiversity research. Here we suggest that only highly philopatric groups can be relevant indicators point...

Insect pollinators are a key component of biodiversity; they also play a major role in the reproduction of many species of wild plants and crops. It is widely acknowledged that insect pollinators are threatened by many environmental pressures, mostly of anthropogenic nature. Their decline is a global phenomenon. A better understanding of their dist...

Insect pollinators are a key component of biodiversity; they also play a major role in the reproduction of many species of wild plants and crops. It is widely acknowledged that insect pollinators are threatened by many environmental pressures, mostly of anthropogenic nature. Their decline is a global phenomenon. A better understanding of their dist...

This is an updated and revised second edition of the Red List of Strepsiptera of the Czech Republic. Altogether 16 species out of 28 currently known from the Czech Republic, are listed as threatened or data deficient.

Bumblebees in Europe have been in steady decline since the 1900s. This decline is expected to continue with climate change as the main driver. However, at the local scale, land use and land cover (LULC) change strongly affects the occurrence of bumblebees. At present, LULC change is rarely included in models of future distributions of species. This...

Anthophora plumipes is a solitary bee species common in Europe, Northern Africa, and the Middle East. Its sibling species A. villosula, which inhabits Eastern Asia, was recently introduced to the USA from Japan and has become naturalized there. The phylogeographic pattern in both species is unknown. Therefore, they are appropriate models for a phyl...

Taxonomy of bees (Hymenoptera: Anthophila) of the Socotra Archipelago is evaluated based on historical and newly available specimens. Four new species of Halictidae are described from the Socotra Island: Austronomia socotrana Pauly & Straka sp. nov., Lasioglossum (Hemihalictus) boswelliae Pauly & Straka sp. nov., Lasioglossum (Sphecodogastra) diosc...

The genus Tachysphex (Crabronidae) from the United Arab Emirates is revised. The following species from the UAE are described as new to science: T. argenteopilosus sp. nov., T. atris sp. nov., T. difficilis sp. nov., T. quasifugax sp. nov., and T. vanharteni sp. nov.