Description of immature stages of Rhinusa species (Coleoptera, Curculionidae, Mecinini) with a focus on diagnostic morphological characters at the species and genus levels.

The mature larvae of the following fourteen Rhinusa species are described and illustrated: Rhinusaantirrhini (Paykull, 1800), R.asellus (Gravenhorst, 1807), R.collina (Gyllenhal, 1813), R.eversmanni (Rosenschoeld, 1838), R.florum (Rubsaamen, 1895), R.herbarum (H. Brisout de Barneville, 1862), R.incana (Kirsch, 1881), R.linariae (Panzer, 1796), R.melas (Boheman, 1838), R.neta (Germar, 1821), R.pilosa (Gyllenhal, 1838), R.rara Tosevski & Caldara, 2015, R.tetra (Fabricius, 1792), and R.vestita (Germar, 1821). The pupae of thirteen of them (except R.incana) were also described. The comparison of larval morphological characters and plant preferences provides evidence supporting the existence of different species groups previously established according to a phylogenetic analysis based on adult morphological characters. The following diagnostic attributes distinguishing the genus Rhinusa are highlighted. For the larvae: (1) pronotal shield indistinct; (2) thoracic prodorsal fold small or even vestigial; (3) abdominal postdorsal folds (especially of segments III-VII) high or even in the form of conical protuberances; (4) cuticle of abdominal segments densely covered with asperities; (5) cuticle without dark spots or dark pigmentation; (6) head suboval, rarely round; (7) labrum usually with 2 als; (8) des1 short or absent, rarely elongated; and (9) fs1-3 usually absent or minute. For the pupae: (1) body stout; (2) head protuberances always present; (3) pronotal protuberances (if present), separated at bases of the pronotum, always wider than higher; (4) abdominal protuberance usually present, wide or round; (5) femora usually with a single fes; and (6) urogomphi short or vestigial. Keys to the larvae and pupae described here are provided. All the characters used for identification are illustrated by photographs or drawings. Biological and distribution data, including new information, are provided for all the species studied.

Developmental Biology and Identification of a Garden Pest, Otiorhynchus (Podoropelmus) smreczynskii Cmoluch, 1968 (Coleoptera, Curculionidae, Entiminae), with Comments on Its Origin and Distribution.

The mature larva and pupa of Otiorhynchus smreczynskii are described and illustrated with complete chaetotaxy for the first time. Five larval instars and the factors for larval growth are determined, and the larval development of this species is comprehensively described. In order to confirm species affiliation, selected larvae were subjected to genetic analysis (mtCOI). Host plants and unique feeding signs of some Entiminae species are presented, and all available data on development are documented and interpreted. Additionally, the morphometry of 78 specimens (48 of O. smreczynskii and 30 of O. rotundus) was examined in order to verify the usefulness of morphological features in distinguishing both species. The female genitalia of both species are illustrated, described and compared with each other for the first time. Finally, the updated distribution of O. smreczynskii is given, and a possible origin of O. smreczynskii and O. rotundus is proposed.

Description of immature stages of Gymnetron species (Coleoptera, Curculionidae, Curculioninae), with particular emphasis on the diagnostic morphological characters at the generic and specific levels.

The immature stages of the following five Palaearctic Gymnetron species are described for the first time: G.tibiellum Desbrochers des Loges, 1900, G.veronicae (Germar, 1821), G.rotundicolle Gyllenhal, 1838, G.melanarium (Germar, 1821), and G.villosulum Gyllenhal, 1838. These species belong to four different groups previously established according to a phylogenetic analysis: the first two belong to the G.veronicae group and the other three to groups respectively bearing their name (G.rotundicolle, G.melanarium, and G.villosulum groups). All these species exhibit several diagnostic characters distinguishing them from each other. Some characters that can be used to separate Gymnetron from other genera in the tribe are also suggested. Three highly significant characters for the larvae and three for the pupae were identified. For the larvae they are: (1) labial palpi with single palpomeres, (2) all spiracles unicameral, and (3) epipharynx with a single pair of mes or none at all. For the pupae they are: (1) the pronotum with prominent pronotal protuberances, (2) abdominal segment VIII with a conical abdominal protuberance dorsally, and (3) very short or even reduced urogomphi. The species studied here are compared with those Gymnetron species already known and with other genera in the tribe Mecinini. Keys to the larvae and pupae described here are provided. All the characters used for identification are illustrated by photographs or drawings.

Morphology of immature stages, biology, and systematic position of the Violet seed weevil, Orobitiscyanea (Linnaeus, 1758) (Curculionidae, Conoderinae, Orobitiditae, Orobitidini).

The mature larva of the weevil species Orobitiscyanea (Linnaeus, 1758), one of only two Palaearctic members of the supertribe Orobitiditae, is re-described, while the pupa is described for the first time. The biology of this species was studied at two sites in Germany. It was reared from seed capsules of Violacanina L. (Violaceae), and feeding holes were observed on V.riviniana Rchb. Adults of Orobitiscyanea and O.nigrina Reitter, 1885, specialists of Viola, show a well-developed escape mechanism, to which contribute a smooth surface, a rounded, nearly spherical body shape, and a seed-imitating thanatosis behaviour. The molytine weevil Leiosomacribrum (Gyllenhal, 1834), the only other known weevil specialist of Viola in Europe, has a smooth surface, also, and is the most spherical species of the genus. The unique characters of the larva and pupa of Orobitiscyanea are discussed in regard to the systematic position of this taxon.

On the Affinities and Systematic Position of Lachnaeus Schoenherr and Rhinocyllus Germar in the Tribe Lixini (Coleoptera: Curculionidae: Lixinae) Based on the Morphological Characters of the Immature Stages.

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.

Adult Postabdomen, Immature Stages and Biology of Euryommatus mariae Roger, 1856 (Coleoptera: Curculionidae: Conoderinae), a Legendary Weevil in Europe.

The larva and pupa of the saproxylic Euryommatus mariae Roger, 1857, the weevil species extremely rare in Europe, are described from Poland. It was reared from galleries in dead branches of a fallen spruce Picea abies. The larval morphology is compared with available larval descriptions of other genera of the supertribe Conoderitae, namely, the Palaearctic Coryssomerus, and the Nearctic Cylindrocopturus and Eulechriopus. The specific characters of the male and female postabdomen are described and illustrated, expressing the peculiar structure of endophallus and spermathecal duct, not seen in any other weevil species. A hypothesis regarding the mechanics of mating in this species is proposed. Euryommatus mariae is recorded for the first time to occur in China.

Sexual Dimorphism in Anthonomus santacruzi (Coleoptera: Curculionidae): a Biological Control Agent of Solanum mauritianum Scopoli (Solanaceae).

There is evident variation in body size amongst Anthonomus santacruzi Hustache, 1924, weevils. The aims of this study were to assess if the variation in body size in A. santacruzi weevils is a result of sexual dimorphism and what features can be used to distinguish males from females. The weevils were collected from field sites in Mpumalanga, South Africa, where they were introduced as biocontrol agents of Solanum mauritianum Scopoli. Body structures and the presence/absence of the tergal notch was examined under an optical stereomicroscope and SEM to assess differences between sexes. The morphometric analysis of the body structures included rostrum length (base-apex and antennal insertion-apex), elytral length and width, pronotum length and width, first tarsus length, first tibia length, funiculus length and total body length. Rostrum length, elytra length and width and total body length were significantly larger in females than in males. A tergal notch in the 8th abdominal tergite was present in males and absent in females. The body structure; of rostrum length, elytra length and width and total body length overlapped between sexes in some specimens. The abdominal tergal notch was found to be the most useful body structure to distinguish males from females in A. santacruzi.

Immature stages of Palearctic Mecinus species (Coleoptera, Curculionidae, Curculioninae): morphological characters diagnostic at genus and species levels.

The immature stages of ten Mecinus species are described for the first time and those of two other species are redescribed, adding important chaetotaxy characters that were missing from previous descriptions. These species belong to six of the nine assemblages of Mecinus species previously established according to a phylogenetic analysis. All these groupings are confirmed on the basis of several characters of mature larvae and pupae. Moreover, all the species show several characters that are useful for distinguishing them from each other, including cryptic species that previously had few differential characters. Some characters that may be useful for separating Mecinus from other genera in the tribe are suggested. To confirm the taxonomic identification of some larvae, the mtCOII gene was obtained and compared with sequences from identified adult specimens. The most important characters for separating the immature stages of the genera and species groups in Mecinus are the number of palpomeres of the labial palpi (1 or 2), the number of air tubes of the thoracic and abdominal spiracles (unicameral or bicameral), and the number of epipharyngeal setae. The species studied herein were compared with those known from other genera in the tribe Mecinini. Two keys, one to the described larvae and the other to the pupae, are provided. Detailed biological data, several of which are new, on some species are reported.

Cleonis pigra (Scopoli, 1763) (Coleoptera: Curculionidae: Lixinae): Morphological Re-Description of the Immature Stages, Keys, Tribal Comparisons and Biology.

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.

Descriptions of the mature larva and pupa of the Scaly strawberry weevil, Sciaphilus asperatus (Bonsdorff, 1785) (Coleoptera, Curculionidae, Entiminae) and observations of its biology.

The mature larva of Sciaphilus asperatus is redescribed and illustrated, and the pupa is described for the first time. Supplements to the identification keys for larvae and pupae of selected Palaearctic Entiminae genera and species are given. Data on the life history, especially oviposition capacity and voltinism, of S. asperatus are provided and discussed, and the number of the six larval instars was confirmed. The economic importance of S. asperatus is briefly highlighted.

First Descriptions of Larva and Pupa of Bagous claudicans Boheman, 1845 (Curculionidae, Bagoinae) and Systematic Position of the Species Based on Molecular and Morphological Data.

In this paper, the mature larva and pupa of Bagous claudicans are described and illustrated for the first time. Measurements of younger larval instars are also given. The biology of the species is discussed in association with larval morphology and feeding habits. Overall larval and pupal morphological characters of the genus Bagous are presented. Confirmation of the larva identification as Bagous claudicans species was conducted by cytochrome oxidase I (COI) sequencing. DNA barcoding was useful for specimen identification of larval stages. The systematic position of the species within the Bagous collignensis-group, based on morphological and molecular results, is also discussed.

Descriptions of immature stages of four species of the genera Graptus, Peritelus, Philopedon, and Tanymecus and larval instar determination in Tanymecus (Coleoptera, Curculionidae, Entiminae).

The mature larva and pupa of Graptustriguttatustriguttatus and the mature larva of Peritelussphaeroides are described for the first time. The larvae of Philopedonplagiatum and Tanymecuspalliatus are re-described. Five larval instars were determined in Tanymecus, thereby correcting doubtful data in the literature. The relationship between larval growth, number of larval instars, head width of the mature larva, and the adult weevil is explained using the example of Tanymecus. The nearly constant ratio of subsequent larval instars in head width ratio, termed "growth factor" and derived from Dyar's ratio, is used for the determination of larval instars. Larval collecting and breeding data are discussed in relation to their significance for the clarification of life-cycles.

Morphological characters of immature stages of Palaearctic species of Cleopomiarus and Miarus and their systematic value in Mecinini (Coleoptera, Curculionidae, Curculioninae).

The relationship between the genera Cleopomiarus and Miarus of Mecinini (Curculionidae, Curculioninae) was tested on the basis of morphological characters from the immature stages. The mature larvae of five Cleopomiarus species (C.distinctus (Boheman, 1845), C.graminis (Gyllenhal, 1813), C.longirostris (Gyllenhal, 1838), C.medius (Desbrochers des Loges, 1893), and C.meridionalis (H. Brisout de Barneville, 1863)), three Miarus species (M.abnormis Solari, 1947, M.ajugae (Herbst, 1795), and M.campanulae (Linnaeus, 1767)), and the pupae of four Cleopomiarus species (C.distinctus, C.graminis, C.longirostris, and C.medius) and two Miarus species (M.abnormis and M.ajugae) are described in detail for the first time. To confirm the taxonomic identification of some larvae, DNA COI barcode was obtained and compared with those of adults. The immature stages of the species herein studied were compared with those known from other genera in tribe Mecinini. It is suggested that Miarus and Cleopomiarus may be monophyletic based on several shared distinctive characters. Larvae of Miarus have a characteristic maxillary mala with six finger-like dms of two sizes (one or two dms very long and the rest of medium length), this feature being apparently unique among weevils. Other genus-specific character states are observed in the pupae, such as the length of setae on the head, rostrum and pronotum, including the number of rs on the rostrum, ds on pronotum, and finally the shape of the urogomphi. A key to the described larvae and pupae were respectively presented. New biological and distributional data on some species are reported.

Description of the immature stages of Larinus vulpes and notes on its biology (Coleoptera, Curculionidae, Lixinae).

Mature larva and pupa of Larinus vulpes (Olivier, 1807) (Curculionidae: Lixinae: Lixini) are morphologically described for the first time and compared with known larvae and pupae of other Larinus species. Very high counts of larval body setae (pronotum with more than 25 setae and postdorsum on meso- and metathorax and also on abdominal segments I-VII with more than 12 setae) are characteristic features of the nominotypical subgenus Larinus. The biology of the species was studied in Ukraine. Echinops ruthenicus and E. sphaerocephalus were identified as host plants of both larvae and adults of this weevil based on the present research in Ukraine, which shows probably oligophagous. Overwintering beetles emerged at the end of May or earlier, then feeding and mating on the host plants. The highest level of adult activity was observed at the end of June. Larvae were endophagous within the flower heads. In July and August, the larvae pupated within inflorescences in a pupation cell. Adults exited the cells at the end of August and did not hibernate on the host plants. Sometimes, larvae and imagines of a new generation were found outside the flower heads in chambers constructed on the stems.

Morphology and identification of the mature larvae of several species of the genus Otiorhynchus (Coleoptera, Curculionidae, Entiminae) from Central Europe with an update of the life history traits.

The mature larvae of 14 Otiorhynchus taxa are described: O. (Otiorhynchus) armadillo (Rossi, 1792), O. (Nehrodistus) armatus Boheman, 1846, O. (Otiorhynchus) aurifer Boheman, 1843, O. (Pocodalemes) crataegi Germar, 1824, Otiorhynchus (Arammichnus) indefinitus Reitter, 1912 (syn. O. dieckmanni Magnano, 1979), O. (Choilisanus) raucus (Fa-bricius, 1777) and 3 taxa of the O. (Otiorhynchus) tenebricosus complex (Herbst, 1784), O. (Otiorhynchus) clavipes (Bonsdorff, 1785), O. (Otiorhynchus) fuscipes (Olivier, 1807) and O. (Otiorhynchus) lugdunensis Boheman, 1843, are described and illustrated for the first time. The larvae of (Otiorhynchus) meridionalis Gyllenhal, 1834, O. (Pendragon) ovatus (Linnaeus, 1758), O. (Zustalestus) rugosostriatus (Goeze, 1777), O. (Metopiorrhynchus) singularis (Linnaeus, 1767), and O. (Dorymerus) sulcatus (Fabricius, 1775) are redescribed and illustrated, and new characters are added. Important characters of the mature larvae (e.g. chaetotaxy, shape of head and body) are explained in detail and illustrated. A key to the identification of the mature larvae of 19 Otiorhynchus taxa is provided. Breeding and collecting data of the larvae are given, and the study is completed by a current overview on the life histories of all treated species.

Comparative morphology of immature stages of two sympatric Tenebrionidae species, with comments on their biology.

The mature larva and pupa of Neomida haemorrhoidalis are described and illustrated for the first time. The mature larva of Bolitophagus reticulatus is completely redescribed and illustrated, and its pupa is described for the first time. The differential diagnosis of the two species is presented. Information about their biology and life history is also given.

Immatures of Palaearctic species of the weevil genus Sibinia (Coleoptera, Curculionidae): new descriptions and new bionomic data with suggestions on their potential value in a phylogenetic reconstruction of the genus.

The larvae and pupae of six species of the Palaearctic genus Sibinia Germar, 1817 are described in detail for the first time. Five of them develop in seeds of Caryophyllaceae and belong to Sibinia (s. str.): S. attalica Gyllenhal, 1835; S. femoralis Germar, 1824; S. tibialis Gyllenhal, 1835; and S. viscariae (Linnaeus, 1760), which are included in the S. femoralis group, and S. sicana Ragusa, 1908, which is included in the S. unicolor Fåhraeus, 1843 group. The sixth species is S. sodalis Germar, 1824, which develops in seeds of Plumbaginaceae and belongs to the subgenus Dichotychius Bedel, 1885. The larvae and pupae of these species are compared with those previously described for some species of the third subgenus, Microtychius Casey, 1910 from the Americas. Some larval characters, but no pupal ones, are useful to support the three subgenera and the two previously mentioned groups of Sibinia s. str., which were previously postulated based on a few adult morphological characters. The immatures of Sibinia are also compared with those of the closely related genus Tychius Germar, 1817, providing some distinctive characters between both genera. New bionomic data on larval and pupal development and adult emergence are reported for all the described species. These data suggest that species in this genus are highly homogeneous in life history traits.

First descriptions of immature stages of the weevils Bagous elegans, B. aliciae, and B. lutulosus.

Last-instar larvae of Bagous elegans (F.), Bagous aliciae Cmoluch, and Bagous lutulosus (Gyllenhal), and the pupa of B. elegans, are described and illustrated for the first time. Biology of these species is analyzed in association with larval morphology and feeding habits. Overall larval and pupal morphological diagnoses of the genus Bagous are updated.

Immatures of Palaearctic species of the weevil genus Tychius (Coleoptera, Curculionidae): new descriptions and new bionomic data with an evaluation of their value in a phylogenetic reconstruction of the genus .

Larvae of 14 species and pupae of 12 species of Palaearctic Tychius Germar, 1817 are described for the first time. Larvae and pupae of T.meliloti Stephens, 1831, T. squamulatus Gyllenhal, 1835 and T. quinquepunctatus (Linnaeus, 1758), are redescribed with addition of new characters. They belong to 10 of 22 groups of species assembled through adult morphological characters in this region and, like all other Tychius with known biology, the studied species live on Leguminosae Papilionoideae, belonging to the tribes Genisteae, Loteae, Galegeae, Trifolieae and Vicieae. Generally larvae, but not pupae, show a few characters useful to support some groupings previously postulated on adult morphology, and also suggest some phylogenetic relationships among groups although these are partly weak because of several clear parallelisms or convergences. One of the most numerous and better known group of species, the T. stephensi group living on Trifolieae, is supported by two distinctive larval character states, whereas all the other groups seem to be distinguishable from each other at least by a unique larval character state. New bionomic data concerning larval and pupal development and adult emergence are reported for all the described species. These data confirm that this genus is highly homogeneous in habits and times of development, with unique adaptive differences in adult emergence and overwintering according to the single or double seasonal flowering of the host plant. On the basis of morphological characters of immatures and adults, a possible concordance between the evolution of Tychius and that of their host plants is discussed.

Descriptions of immature stages of the weevil Lixus punctiventris Boheman, 1835 (Coleoptera, Curculionidae, Lixini).

Last instar larva of Lixus punctiventris Boheman is redescribed and illustrated, its pupa is described and illustrated for the first time. Biology of this species is analyzed in association with larval morphology and feeding habits. Overall larval and pupal morphological diagnoses of the genus Lixus and larval diagnosis of the tribe Lixini are updated.