Biology and morphology of immature stages of Adosomus roridus (Coleoptera: Curculionidae: Lixinae)

The mature larvae and pupae of Lixus (Ortholixus) bituberculatus Smreczyński, 1968 and L. (Dilixellus) neglectus Fremuth, 1983 (Curculionidae: Lixinae: Lixini) are described and compared with known larvae of 21 other Lixus and 2 Hypolixus taxa. The mature larva and pupa of L. bituberculatus are the first immature stages described representing the subgenus Ortholixus. The larva of L. neglectus, in the subgenus Dilixellus, is distinguished from the known larvae of four species in this subgenus by having more pigmented sclerites on the larval body. All descriptions of mature larvae from the tribe Lixini, as do all known species from the tribe Cleonini, fit the diagnosis of the mature larva of the Lixinae subfamily. Furthermore, new biological information of these species in the Czech Republic, Slovakia and Romania is provided. For L. bituberculatus, a chicory, Cichorium intybus L. (Asteraceae), is identified as a host plant, and L. neglectus is found on dock Rumex thyrsiflorus Fingerh. (Polygonaceae). Both species are probably monophagous or oligophagous. Adults of L. bituberculatus often inhabit host plants growing in active, dry and sunny pastures with sparse patches without vegetation, being mostly active during the night in April/May and then again in September, when the highest activity levels are observed. Adults of L. neglectus inhabit dry grasslands on sandy soils with host plants, being active during the day from May to September, with the highest level of activity in May/June and September. The larvae of both species are borers in the stem and root of the host plant, and they pupate in root or root neck. Adults leave the pupation cells at the end of summer and do not hibernate in the host plants. Finally, Romania is a new geographic record for L. bituberculatus.

Mature larvae and pupae of Cleonis pigra (Scopoli, 1763) (Curculionidae: Lixinae: Cleonini) are morphologically described in detail for the first time and compared with known larvae and pupae of other Cleonini species. The results of measurements and characteristics most typical for larvae and pupae of Cleonini are newly extracted and critically discussed, along with some records given previously. Keys for the determination of selected Cleonini species based on their larval and pupal characteristics are attached. Dyar’s law was used for the estimation of a number of larval instars of C. pigra. Descriptions of habitats, adult behavior, host plants, life cycle, and biotic interactions are reported here. Adults and larvae feed on plants from the Asteraceae family only (genera Carduus, Cirsium, Centaurea, and Onopordum). Oviposition occurs on the base of the plant stem or the root neck. In the process of larval development, a fusiform gall forms. C. pigra and Cyphocleonus achates can coexist in the same locality. In open habitats, the weevils become the prey of carnivorous animals.

Mature larvae and pupae of Lachnaeus crinitus Schoenherr, 1826 and Rhinocyllus alpinus Gültekin, Diotti and Caldara, 2019 and pupae of R. conicus (Frölich, 1792), belonging to the Lixini (Curculionidae: Lixinae), are morphologically described for the first time. They possess all the characters considered distinctive in the immature stages of this tribe and are distinguishable from all the related genera by a combination of some characters (e.g., presence of endocarina, shape of premental sclerite; the number of pds on the abdominal segments; size and presence of urogomphi). It is emphasized that the controversial tribe Rhinocyllini is not supported by the characters of the larvae and pupae of Rhinocyllus and that the two subgenera of this genus, Rhinocyllus s. str. and Rhinolarinus, are separable from each other not only by characters of the adult but also distinctive characters of the larvae and pupae. These results confirm that the morphology of the immature stages, which is usually overlooked, can be very important for the purpose of identifying new characters that are useful for clarifying taxonomical and phylogenetic complex situations based only on the study of the imagoes.

Acta Carpathica Occidentalis, peer-reviewed scientific journal - results of original natural science research in natural sciences, especially from the Carpathian region of the Czech and Slovak Republics.

Study of Orthoptera and earwigs was conducted in Tovačov gravel pit in 2014. We have recorded 18 species of Orthoptera and 3 species of earwigs. The most significant recorded species are Cepero’s ground-hopper (Tetrix ceperoi), pygmy mole cricket (Xya variegata), Italian tree cricket (Oecanthus pellucens) and riparian earwig (Labidura riparia). Tovačov gravel pit poses the northernmost locality of T. ceperoi and X. variegata in the Czech Republic and the northernmost known locality in Moravia for O. pellucens. For the L. riparia, we present a founding from Tovačov together with another finding from Olomouc vicinity, which is currently the northernmost locality within Moravia. Our findings display recent spatial expansion of some thermophilous species. Moreover, we emphasize importance of (post)-industrial areas as secondary habitats for specialised endangered species