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The taxonomy of the syrphid genus Chrysotoxum Meigen, 1803 (Diptera: Syrphidae), is complex and currently under scrutiny. Two new species allied with Chrysotoxum vernale, one from the Western Mediterranean, Chrysotoxum hispanicum sp. n. and the other from the Eastern Mediterranean, Chysotoxum anatolicum sp. n., are described and illustrated. Chrysotoxum hispanicum sp. n. is distinguished from the similar C. vernale Loew by the size of the yellow abdominal fasciae and shape of surstyli. Chrysotoxum anatolicum sp. n., known only from females, possesses an almost entirely yellow-pigmented wing, unusual amongst the other studied species of the C. vernale group. Additionally, C. hispanicum sp. n. and C. anatolicum sp. n. are separated from each other, as well as from other species of the C. vernale group by COI and ITS2 gene markers. An identification key to the West Palaearctic species of the C. vernale group is provided. [ABSTRACT FROM AUTHOR]

The genus Eumerus Meigen 1822 (Diptera: Syrphidae) is widely distributed in the Old World, though recently introduced into America, and their larvae feed on decaying vegetal material and/or inside underground storage organs of many plants, sometimes generating economic losses as pests. However, little is known about Eumerus larval cycles and their interactions with host plants. Here, immatures of three Eumerus species from different continents are described, noting their feeding habits and host plants. Larvae of Eumerus figurans Walker 1859 were obtained from Hawaiian cultured ginger roots; puparium of Eumerus alpinus Rondani 1857 originated from larvae collected in Asphodelus ramosus L. in France; puparia of Eumerus superbus Shannon 1927 were reared from larvae found in two Zamiaceae species from Australia. Mitochondrial COI sequences served for diagnosing E. figurans larvae. Optical and scanning electron microscopy were used to describe body features, head skeletons, anterior spiracles, pupal spiracles, and posterior respiratory processes. Overall, E. alpinus resembles E. nudus Loew 1848 immatures. Eumerus superbus has a remarkable morphology among all described immatures of the genus, being the only Eumerus reported from gymnosperms. Head skeleton of E. figurans suggests this species is a filtering one. Present findings show that larvae of Eumerus can be separated at the species level and that this genus is polyphagous, feeding on a wide range of plant tissues and taxa, including commercial species. This study emphasizes immature stages and breeding sites as important means to understand species life cycles and the interactions with their host plants and ecosystems. [ABSTRACT FROM AUTHOR]

Understanding the responses of insects to ecological variables provides information that is fundamental for their conservation. The present study took place in three different landscapes (three plots of 10 × 10 km each) in a typical Mediterranean ecosystem of a Spanish national park. Each landscape included three vegetation types, grasslands, scrublands, and woodlands, and was characterised by a dominant vegetation type. Our objectives were: (1) to assess how important the influence of the dominant vegetation type and the vegetation type of sites are on hoverfly (Diptera: Syrphidae) diversity at landscape scale; (2) to assess whether scrublands are contributing to the loss of hoverfly diversity in an ecosystem with a long history of human use. In order to achieve these goals, we compared hoverfly diversity among sampling sites by prospecting all three diversity levels, alpha, beta and gamma, at each landscape. We sampled adult hoverflies at 18 sites located in different vegetation types within the three landscapes. No evidence was found that demonstrated an effect of the dominant vegetation type on alpha or beta diversity of sites, but the vegetation type of sites did have an affect. The highest species richness was found in woodland sites, particularly in the grassland-dominated landscape. At each landscape, beta diversity among sampling sites contributed more to gamma diversity than alpha diversity did. Our results highlight the need to focus on the conservation of woodland remnants of grassland-dominated landscape and scrubland-dominated landscape in order to preserve a large proportion of the biodiversity of Cabañeros hoverflies, as well as on the maintenance of the mosaic landscape, which is linked to high beta diversity, typical in many Mediterranean ecosystems. We emphasise the importance of open clearings in the vast mass of scrubland in the scrubland-dominated landscape in order to provide extra resources for the hoverflies. [ABSTRACT FROM AUTHOR]