Antonio Ricarte’s research while affiliated with University of Alicante and other places

Records of two species of hoverflies (Diptera, Syrphidae), Hammerschmidtia ferruginea (Fallén, 1817) and Megasyrphus erraticus (Linnaeus, 1758), are here provided for the first time in the Iberian Peninsula, both records located at the southern edges of these genera ranges in Europe. The new data is reported following fieldwork in the Pyrenees of Huesca and Lleida provinces (Spain) and consultation of the 'Museu de Ciències Naturals de Barcelona' entomological collection. The importance of these findings is discussed in the frame of the conservation of these species’ habitats.

The largest genus of Palaearctic Syrphidae, Cheilosia Meigen, 1822 (Syrphidae: Rhingiini), is currently under revision in the Ibero-Balearic region (Iberian Peninsula + Balearic Islands). Prior to this study, various species groups with putative phylogenetic support were defined for this genus of complex taxonomy. The group of Cheilosia melanura Becker, 1894 includes species distributed all over Europe, with some of these species being similar each other in both morphology and genetics. After recent fieldwork in different Iberian localities and consultation of entomological collections, a new species from Sierra Nevada (Granada, Spain) was uncovered, described, and illustrated. Data on diagnostic characters, intraspecific variability, and adult biology were also provided. Maximum likelihood analyses of the fragment “C” of the 5′ end of the cytochrome c oxydase subunit I (COI-5′) and complete COI-5′ were performed to explore and support morphological species concepts within the group. The Spanish-endemic Cheilosia andalusiaca Torp Pedersen, 1971 is recognised here to be part of the C. melanura group based both on morphological and molecular evidence. Cheilosia carbonaria Egger, 1860 and Cheilosia cynocephala Loew, 1840 from the Iberian Peninsula are reported for the first time based on specimens originating in the Spanish Pyrenees. An identification key for the Iberian species of the C. melanura group is provided.

Increasing knowledge of the genus Brachyopa Meigen, 1822 (Diptera, Syrphidae) in the Iberian Peninsula: new findings from the eastern region

The genus Paragus Latreille, 1804 with over 100 species of hoverflies (Diptera: Syrphidae) is widely distributed except for Antarctica. The larval biology of these hoverflies is well known since they develop in aphid colonies, which are often of economic importance. However, the immature stages of only 9 of the 27 known larvae of genus Paragus are described. Paragus (Paragus) hyalopteri Marcos-García & Rojo, 1994, is a Palaearctic species described from Spain. Its larva has only been found preying on the aphid Hyalopterus pruni (Geoffroy, 1762) (Hemiptera: Aphididae), on several species of fruit trees and on leaves of Arundo donax L., and Phragmites spp. Here for the first time the full life cycle of a Paragus hoverfly is described including egg, all three larval stages and the puparium. Eggs, larvae and pupae of P. hyalopteri were collected on leaves of Phragmites australis (Cav.) among aphid colonies of H. pruni, and their morphology analyzed and described in detail using stereomicroscope and Scanning Electron Microscope techniques. To facilitate the diagnosis of Paragus larvae, a key to all known larvae of Paragus is provided.

Comprising nearly 300 described species, Eumerus Meigen, 1822, is one of the most speciose syrphid genera worldwide, and its taxonomic diversity is remarkable in the Mediterranean basin. The Eumerus barbarus (Coquebert, 1804) group consists of four species in the western Mediterranean. Although the phenotypic variability of this species group has been commented on in previous studies, it has never been contrasted with molecular data. In the present work, the morphological variation found in 300+ specimens of this species group from the western Mediterranean is explored and tested against the COI mitochondrial DNA (mtDNA). The highest phenotypic disparity was found in E. barbarus and Eumerus sulcitibius Rondani 1868. The integrative approach has not revealed cryptic diversity within the species E. barbarus but in E. sulcitibius. As a result, a new species close to E. sulcitibius was discovered, Eumerus sardus Aguado-Aranda, Ricarte & Hauser sp. n., from Sardinia, Italy. The new insular species is here described, illustrated, and discussed. A total of twenty-three haplotypes of COI mtDNA were identified amongst the analyzed Mediterranean specimens of E. barbarus, whereas two and five haplotypes were distinguished in the Iberian specimens of E. sulcitibius and Eumerus gibbosus van Steenis, Hauser & van Zuijen, 2017, respectively. Moreover, the first known barcodes of E. gibbosus and Eumerus schmideggeri van Steenis, Hauser & van Zuijen, 2017 were obtained, and the distribution ranges of all species are mapped. An updated dichotomous key to the males of the E. barbarus group from the western Mediterranean is provided.

Eumerus colladoi Ricarte & Aguado-Aranda is reported from France for the first time. New data on its biology and habitat preferences are provided. The known distribution of the species in France is mapped.

With 14 species, Pelecocera Meigen, 1822 is a scarce and small genus of hoverflies (Diptera: Syrphidae: Rhingiini) from the Holarctic Region. Apart from the finding of larvae of Pelecocera (Chamaesyrphus) japonica (Shiraki, 1956) in fungi in Japan, the larval biology of these hoverflies is virtually unknown. The early stages of all Pelecocera species are undescribed. The adults of Pelecocera (Pelecocera) tricincta Meigen, 1822 and Pelecocera (Chamaesyrphus) lugubris Perris, 1839 are found in Palearctic conifer forests with sand dunes. We here report the first morphological evidence of the immature stages of Pelecocera (P. lugubris and P. tricincta), as well as specific data on their breeding sites. Larvae of both species were collected feeding on the hypogean basidiomycete Rhizopogon luteolus Fr. & Nordholm, 1817 in Denmark in 2021. The first larval stage and second larval stage of P. tricincta, the third larval stage of P. lugubris, the anterior respiratory process, and the posterior respiratory process of the puparia of these two species were analyzed and studied using stereomicroscope and scanning electron microscope techniques. The chaetotaxy of the puparium of each species is also described and illustrated. A taxonomic diagnosis of the larvae of the genus Pelecocera is proposed to separate them from the larvae of other genera of the tribe.

The genera Eumerus and Merodon (Syrphidae: Merodontini) form together the most speciose grouping of hoverflies in the Palaearctic Region. However, little is known about the morphology and biology of their larvae. The few larvae of Eumerus and Merodon that have been uncovered are phytophagous in underground organs of plants (some Eumerus and all Merodon) or saprophagous in a variety of plants' parts (the reminder of Eumerus). In this study, the second larval stage (L2) of Eumerus lyneborgi Ricarte & Hauser, 2020 and both the larva (L2) and puparium of Merodon constans (Rossi, 1794) are described for the first time. Larvae of E. lyneborgi were found in a decaying stem of Cyphostemma juttae (Dinter & Gilg) Desc., 1960 (Vitaceae) in Namibia (Africa), while larvae of M. constans were collected in bulbs of Leucojum vernum Linnaeus, 1753, (Amaryllidaceae) in France (Europe). Morphology of the immature forms was studied by observation and imaging with stereomicroscopy and scanning electron microscopy. The head skeleton of E. lyneborgi larvae was found to be of the filter feeding type, i.e., in accordance with a saprophagous trophic regime, while that of M. constans was typically phytophagous. Variability in certain characters of the M. constans early stages is described and discussed in relation to the adult form and molecular information published in literature. An updated identification key to all known third larval stages/puparia of Merodon is provided.