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

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

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

Beetles (Coleoptera) of wetlands and other aquatic habitats in the Polish part of the Polesie region found during the Balfour-Browne Club Meeting 2016

A total of 27 sites in the Polish part of the Polesie region were investigated for aquatic and wetland-associated beetles during the field sessions of the Balfour-Browne Club Meeting (23-30.05.2016). These comprised a mixture of fens and Sphagnum peat bogs, ditches draining fens, oxbow lakes of the Bug River, and sand excavations. A total of 408 species, belonging to all three sub-orders of beetle and 34 families were captured, including 351 species related to the aquatic environment (true water beetles – 157, phytophilous water beetles – 32, facultative water beetles – 1, false water beetles – 156, shore beetles – 157). Numerous rare, protected, species and those endangered in Poland or neighbouring countries were found. Information on three species (Agabus pseudoclypealis, Hygrotus polonicus and Berosus geminus) is important for our understanding of their geographical range limits. In the case of B. geminus, new data, in conjunction with information from Ukraine, points to the existence of an isolated island of occupancy in Polish and Ukrainian Polesie. Analysis of the material collected also reveals the high value of the study area, both nationally and internationally, for the protection of wetland beetle biodiversity

Larinus

Key to the mature larvae of the genus Larinus 1. More than 40 setae on pronotum (Fig. 23). Endocarina absent (Figs. 15, 16).......... L. (s. str.) pollinis (Laicharting, 1781) - Less than 15 setae on pronotum (Figs. 9, 37,51). Endocarina present (Figs. 1, 2, 29, 30, 43, 44)....................... 2 2. Abdominal segment I–VII without prs, only 5 pds, and 1 dpls (Fig. 10). Spiracular area in meso- and metathoax with only one seta (ss) (Fig. 9)...................................................... L. (Larinomesius) obtusus Gyllenhal, 1835 - Abdominal segment I–VII 1 prs, 7 pds, 2 dpls and 2 vpls (Figs. 38, 52). Spiracular area in meso- and metathoax with three or four setae (ss) (Figs. 37, 51)............................................................................. 3 3. Setae on thorax and abdomen long (Figs. 37–39). Abdominal segment VIII with 2 dpls and 2 vpls (Fig. 39). Spiracular area in meso- and metathoax with three setae (ss) (Fig. 37). Des 4 close to des 3 (Figs. 29, 30)................................................................................................... L. (Phyllonomeus) sturnus (Schaller, 1783) - Setae on thorax and abdomen relatively short (Figs. 51–53). Abdominal segment VIII. with 1 dpls and 1 vpls (Fig. 53). Spiracular area in meso- and metathoax with four setae (ss) (Fig. 51). Des 4 close to des 5 (Figs. 43, 44)......................................................................................... L. (Phyllonomeus) turbinatus Gyllenhal, 1836Published as part of Gosik, Rafał & Skuhrovec, Jiří, 2011, Descriptions of mature larvae and pupae of the genus Larinus (Coleoptera: Curculionidae, Lixinae), pp. 1-25 in Zootaxa 3019 on page 23, DOI: 10.5281/zenodo.27866

Larinus (Phyllonomeus) sturnus Schaller 1783

Larinus (Phyllonomeus) sturnus (Schaller, 1783) Scherf 1964: 132 (key), 134–135 (description), Figs. 151–153; Nikulina et al. 2004: 25 (key). Material. (77 larvae of different larval instars, 20 pupae), collected in the flower heads of cabbage thistle (Cirsium oleraceum (L.) Scop.)) growing in wet meadows and in the flower heads of welted thistle (Carduus crispus L.) growing in psammophilous grass communities: POLAND centr. or., wet meadow in Łąki ad Nałęczów, UTM nets: EB 88, 7. and 25.vi., 10. and 24.vi., 5. and 20.viii., 5.ix. 2009 (65 larvae, 20 pupae); POLAND mer. or., wet meadow in Susiec, UTM nets: FA 58, 20.viii. 2009 (5 larvae); POLAND centr., sand grass communities in Stara Słupia, UTM nets: EB03, 12.vii. 2009 (5 larvae); sand grass communities in Pińczów, UTM nets: DA 69, 12.vii. 2009 (2 larvae), all R. Gosik leg. Differential diagnosis. Mature larva. Endocarina present (x L. pollinis) (Figs. 29, 30). Des 4 close to des 3 (x L. turbinatus) (Figs. 29, 30). Less than 15 setae on pronotum (x L. pollinis) (Fig. 37). Spiracular area in meso- and metathoax with three setae (x L. obtusus, L. pollinis, L. turbinatus) (Fig. 37). Abdominal segment I–VII with 1 prs, 7 pds, 2 dpls and 2 vpls (x L. obtusus, L. pollinis) (Fig. 38). Setae on thorax and abdomen long (Figs. 37, 38) (x L. turbinatus). Pupa. Sas on head as horns (x L. obtusus, L. pollinis, L. turbinatus) (Figs. 40, 41). Less than 15 setae on pronotum (x L. pollinis) (Fig. 41). Seta 1 on abdominal segment I. near anterior margin, remaining 8 setae close to posterior margin (x L. pollinis, L. turbinatus) (Fig. 41). Pc distinct and long (x L. obtusus, L. pollinis) (Figs. 40– 42). Description of mature larva. COLORATION. Head brown or dark brown. All thoracic and abdominal segments white or light-yellow. Cuticle minutely spiculate. HEAD CAPSULE AND MOUTH PARTS. Head width: 2.0–2.3 mm (mean 2.2 mm), oval, endocarinal line present, reaches middle of the frons. Des 1 and des 3 located almost on frontal suture, des 2 and des 4 located in central part of epicranium, des 5 placed anterolaterad, of equal length (Figs. 29, 30). Fs 1, fs 2 and fs 3 placed medially, fs 4 and fs 5 located posterolaterad, of equal length (Figs. 29, 30). Les 1, 2 and ves slightly shorter than des. Epicranial area with group of 4 pores; one pore near des 1, the next close des 2, remaining two pores placed laterally. Antenna with sensorium conical triangular, relatively short, located medially; basal membranous article with 3 triangular sensillae (Fig. 31). Labrum (Fig. 32 —left side) approx. 2.3 times as wide as long with 3 pairs of hairform lrms 1-3 of different length; lrms 2 3 times shorter than lrms 1 and lrms 3; anterior margin double sinuate. Clypeus (Fig. 32 —left side) 2.3 times as wide as long with 3 pairs of short cls 1-3 of unequal length, located posterolaterad; cls 1 3 times shorter than cls 2 and cls 3; anterior margin slightly rounded to the inside. Epipharynx (Fig. 32 —right side) with 5 pairs of blunt, finger-like als of different length; 2 pairs of ams, ams 2 distinctly longer than ams 1; two pairs of mes, triangular, blunt; labral rods (lr) easily visible, very long, strong converging posteriorly. Mandibles (Fig. 33) slightly truncate; mds 1, 2 almost of equal length. Maxilla (Fig. 34): stipes with 2 stps 1, 2, 2 pfs 1, 2 and 1 mbs of different length; mala with 7 slightly curved dms, different in length; vms 1-4 short, almost of equal length; vms distinctly shorter than dms. Maxillary palpi with two palpomeres; without maxillary palpi seta; length ratio of basal and distal palpomeres: 1:0.7; distal palpomere with group of 6 conical, cuticular apical processes. Praelabium (Fig. 35) heart-shaped, with a pair of plbs; margin of ligula slightly curved to the inside, ligs 1-3 sharp, short; premental sclerite well visible. Labial palpi with two palpomeres; length ratio of basal and distal palpomeres, 1:0.6; distal palpomere with 4 conical cuticular apical processes; both palpomeres with 1 dorsal pore. Postlabium (Fig. 35) with 3 pairs of pslbs, different in length, located laterally and anterolaterally. THORAX AND ABDOMEN. Body length: 13.5–20.5 mm (mean 17.5 mm) elongated, curved (Fig. 36). The widest place in the body (metathorax) up to 4.0 mm. Abdominal segments I–IV almost equal in length, slightly smaller than abdominal segments V–VI; next abdominal segments decreasing gradually to the terminal parts of the body. Spiracles on the abdomen in median parts of abdominal segments I–VIII (Fig. 38). Chaetotaxy of the body rather reduced. Setae medium long, light yellow. Thorax. Prothorax (Fig. 37) with 11 prns, 2 dpls, 2 vpls and 1 msts. Mesothorax (Fig. 37) with 1 prs, 5 pds, 1 alar s., 3 ss unequal in length, 1 dpls, 2 vpls and 1 msts. Chaetotaxy of metathorax (Fig. 37) similar to mesothoracal. Each pedal area of thoracic segments well separated, with 4 long and 3 short pda. Abdomen. Abdominal segments I–VII (Fig. 38) with 1 prs, 7 pds, 1 dls, 1 ss in the spiracular area, 2 dpls, 2 vpls, 1 lsts and 2 short msts. Abdominal segment VIII (Fig. 39) with 7 pds, 2 dpls, 2 vpls, 1 lsts and 2 short msts. Abdominal segment IX (Fig. 39) with 6 ds, 3 ls of different length and 3 sts of different length. All anal lobes on abdominal segment X (Fig. 39) without setae. Description of pupa. COLORATION. Body white-gray or yellowish. The cuticle minutely spiculate, light yellow in the vicinity of the bases of setae. MORPHOLOGY (Figs. 40–42). Body length: 10.2–12.5 mm, in the widest region: 5.3–5.9 mm. Body elongated, slender. Rostrum long, approx 2.7 times as long as wide, reaching up to the metacoxae. Antennae relatively long and slender. Pronotum 1.6 times as wide as long. Abdominal segments I–IV of equal length; next abdominal segments diminish gradually to the end of the body. Abdominal segment VIII almost semicircular; IX distinctly smaller than other abdominal segments. CHAETOTAXY (Figs. 40–42). Setae distinct, medium long, unequal in length, on pronotum placed on protuberances. Head capsule includes 2 vs, 2 sos, 1 os and 4 pas. Rostrum with 5 rs, 2 setae placed medially, remaining 3 setae on anterior margin of rostrum. There is also a seta on each of mandibular thecae (mts). Setae on head and rostrum straight, shorter than setae on thoracic and abdominal segments. Pronotum with 1 pair of superapical setae (sas) placed on conical, divided protuberances; 5 pairs of lateral setae (ls 1-5); 2 pairs of discal setae (ds 1, 2); 1 pair of superlateral setae (sls) and 4 pairs of posterolateral setae (pls 1-4). Dorsal parts of mesothorax with 1 pair of setae placed posteromedially and the next 5 pairs distributed along its anterior margin. Chaetotaxy of metathorax similar to mesothoracal. Each apex of femora with groups of 3 fes. Bases of setae with light yellow ring. Dorsal parts of each of abdominal segments I–VIII with 1 pair of setae placed posteromedially and 8 pairs located along its anterior margin. Setae on abdominal segments VII, VIII placed on conical protuberances. Abdominal segments I–VIII with groups of 4 lateral setae and 3 short ventral setae in regular lines. Abdominal segment IX with 4 pairs of ventral micro-setae and a pair of short, thin dorsal setae. Pseudocerci elongated, slightly curved to the inside. Remarks. Measurements presented by Scherf (1964) did not agree with our results; body length of larvae 13– 15 mm (ours, 19–26 mm) and body length of pupae 12–14 mm (ours, 10.2–12.5 mm). This difference could be caused by different quality of measurements, method of measurement and/or because the thorax and abdomen are not sclerotized and may also be affected by the fixation process, and body length and width are given only for comparison here (Table. 1). Scherf (1964) did not give any other measurements (e.g. head and/ or body width). Chaetotaxy is almost the same apart from a few details, e.g. count of les. Scherf (1964) recorded the presence of three les, but unlike he, we recorded two setae in this region. Descriptions of larvae and also of pupae by Scherf (1964) are brief but informative. Unfortunately, we can not say the same about drawings, which are very poor and almost without any information. Nikulina et al. (2004) mentioned this species only in their key, which is reproduced from Scherf (1964).Published as part of Gosik, Rafał & Skuhrovec, Jiří, 2011, Descriptions of mature larvae and pupae of the genus Larinus (Coleoptera: Curculionidae, Lixinae), pp. 1-25 in Zootaxa 3019 on pages 15-19, DOI: 10.5281/zenodo.27866

Larinus (Phyllonomeus) turbinatus Gyllenhal 1836

Larinus (Phyllonomeus) turbinatus Gyllenhal, 1836 Material. (5 mature larvae, 1 pupa), collected in the flower heads of melancholy thistle (Cirsium heterophyllum L.) growing on wet meadows: CZECH REPUBLIC bor., Liberec env., Janov nad Nisou—Hrabĕtice (5257), N 50 ° 46 '40.5'', E 15 ° 41 '8.09'', 740 m a.s.l., 8.vii. 2008, J. Skuhrovec leg. Differential diagnosis. Mature larva. Endocarina present (x L. pollinis) (Figs. 43, 44). Des 4 close to des 5 (x L. obtusus, L. pollinis L. sturnus) (Figs. 43, 44). Less than 15 setae on pronotum (x L. pollinis) (Fig. 51). Spiracular area in meso- and metathoax with four setae (x L. obtusus, L. pollinis, L. sturnus) (Fig. 51). Abdominal segment I– VII with 1 prs, 7 pds, 2 dpls and 2 vpls (x L. obtusus, L. pollinis) (Fig. 52). Setae on thorax and abdomen relatively short (Figs. 51, 52) (x L. obtusus, L. pollinis, L. sturnus). Pupa. Sas on head, no protuberance with a shape such as horns (x L. sturnus) (Figs. 54, 55). Less than 15 setae on pronotum (x L. pollinis) (Fig. 55). Seta 1 on abdominal segment I. in line with the remaining 7 setae, all close to the posterior margin (x L. obtusus, L. pollinis, L. sturnus) (Fig. 55). Pc distinct and long (x L. obtusus, L. pollinis) (Figs. 54–56). Description of mature larva. COLORATION. Head light brown. All thoracic and abdominal segments white. Cuticle minutely spiculated. HEAD CAPSULE AND MOUTH PARTS. Head width: 1.5–1.7 mm (mean 1.6 mm), suboval, slightly oblate laterally, endocarinal line present, reaches middle of the frons. Des 1 and des 2 located in the central part of the epicranium, des 3, des 4 and des 5 located near the frontal suture, of equal length (Figs. 43, 44). Fs 1, fs 2 placed along frontal suture, fs 3, fs 4 and fs 5 located close to epistoma, of equal length (Figs. 43, 44). Les 1, 2 and ves 1, 2 slightly shorter than des. Epicranial area with group of 3 pores; one located near des 1, with the next two pores placed laterally. Antenna with sensorium conical triangular, relatively long and slender, located medially; basal membranous article with 6 triangular sensillae (Fig. 45). Labrum (Fig. 46 —left side) approx 1.7 times as wide as long with 3 pairs of long, bacilliform lrms of different length; lrms 2 slightly longer than lrms 1 and lrms 3; all lrms distinctly placed on protuberances; anterior margin double sinuate. Clypeus (Fig. 46 —left side) 3 times as wide as long with 2 pairs of long, hairform cls, unequal in length, located posterolaterally; anterior margin slightly rounded to the inside. Epipharynx (Fig. 46 —right side) with 5 pairs of blunt als of different length; anteriorly, 2 pairs of ams, with ams 1 distinctly longer than ams 2; labral rods (lr) very short, converging posteriorly. Mandibles (Fig. 47) relatively broad, highly truncated; short, hairform mds 1, 2 almost of equal length. Maxilla (Fig. 48) stipes with 1 stps and 2 pfs, equal in length; mala with 9 bacilliform dms, different in length; vms 1-2 short, almost equal in length; vms distinctly shorter than dms. Maxillary palpi with two palpomeres; basal palpomere with 1 mxps and two pores; length ratio of basal and distal palpomeres: 1:0.7; distal palpomere with group of 6 conical, cuticular apical processes and one pore. Praelabium (Fig. 49) heartshaped, with 1 plbs; margin of ligula sinuate and 3 micro ligs of different length; premental sclerite well visible. Labial palpi with two palpomeres; length ratio of basal and distal palpomeres 1:0.8; distal palpomere with 5 conical cuticular apical processes; basal palpomere with 1 dorsal pore. Postlabium (Fig. 49) with 3 pslbs of different length, one seta located medially, remaining two setae laterally. THORAX AND ABDOMEN. Body length: 8.0–12.0 mm (mean 10.5 mm), relatively elongated, slightly curved (Fig. 50). The widest place in the body (metathorax) up to 3.1 mm. Abdominal segments I–IV almost equal in length, slightly smaller than abdominal segments V–VI, with the next abdominal segment decreasing gradually to the terminal parts of the body. Spiracles on the abdomen in the lateral regions of abdominal segments I–VIII (Fig. 52). Chaetotaxy of the body reduced, poorly distinguished. Setae thin, short, light yellow. Thorax. Prothorax (Fig. 51) with 14 prns almost in equal length, 2 vpls and 1 msts. Mesothorax (Fig. 51) with 1 prs, 5 pds, 1 as, 4 ss different in length, 1 dpls, 2 vpls and 1 msts.Chaetotaxy of metathorax (Fig. 51) similar to mesothoracal. Each pedal area of thoracic segments well separated, with 8 pda of different lengths. Abdomen. Abdominal segments I–VII (Fig. 52) with 1 prs, 7 pds, 1 dls, 1 ss in the spiracular area, 2 dpls, 2 vpls, 1 lsts and 2 short msts. Abdominal segment VIII with 1 prs and 7 pds of different length, 2 dls, 1 ss, 1 dpls, 1 vpls, 1 lsts and 2 short msts. Abdominal segment IX (Fig. 53) with 5 ds, 2 ls and 2 sts (Fig. 53). Each anal lobe on abdominal segment X (Fig. 53) with 1 micro-seta. Description of pupa. COLORATION. Body white or yellowish; cuticle smooth. MORPHOLOGY (Figs. 54–56). Body length 7.8 mm, width in the widest region (between end of mesofemurs): 3.9 mm. Body elongated, slender, slightly curved. Rostrum medium long, approx. 1.7 times as long as wide, reaching up to the mesocoxae. Antennae long and slender. Pronotum almost 2.0 times as wide as long. Abdominal segments I–IV of equal length; following abdominal segments diminish gradually to the end of the body. Abdominal segments VII–IX distinctly smaller than other abdominal segments. CHAETOTAXY (Figs. 54–56). Setae distinct, medium long, light yellow, unequal in length, placed on small protuberances on the pronotum. Head capsule includes 1 vs, 2 sos, 1 os and 4 pas. Rostrum with 4 rs, 1 pair placed medially, remaining 3 pairs located on the anterior margin of rostrum; and a pair of mts. Setae on head capsule and rostrum straight, almost of equal length, slightly shorter than those on thoracic and abdominal segments. Pronotum with 1 sas placed on small, conical, protuberance; 6 ls; 2 ds; 2 sls and 4 pls. Dorsal parts of mesothorax with 6 pairs of setae, 1 pair placed posteromedially and 5 pairs medio-laterally in a group. Chaetotaxy of metathorax similar to mesothoracal. Each apex of the femora with groups of 3 fes. Dorsal parts of abdominal segments I–VIII with 1 pair of setae placed posterolaterally and 8 pairs distributed along its anterior margin. Setae on abdominal segments VI– VIII placed on conical protuberances. Abdominal segments I–VIII with groups of 4 lateral setae and 3 pairs of short ventral setae in regular lines. Abdominal segment IX with 4 pairs of ventral micro-setae and 3 pairs of short, thin dorsal setae. Pseudocerci elongated, slightly curved to inside. Remarks. Scherf (1964) mentioned this species in his book, but he recorded only descriptions of its eggs, larval biology and parasitoids.Published as part of Gosik, Rafał & Skuhrovec, Jiří, 2011, Descriptions of mature larvae and pupae of the genus Larinus (Coleoptera: Curculionidae, Lixinae), pp. 1-25 in Zootaxa 3019 on pages 19-23, DOI: 10.5281/zenodo.27866

RAFAŁ GOSIK & PETER SPRICK (2013) Morphology and identification of the pupae of several species of soil-dwelling broad-nosed weevils from Central Europe (Coleoptera, Curculionidae, Entiminae). Zootaxa, 3731(4): 445-472.

Gosik, Rafał, Sprick, Peter (2013): RAFAŁ GOSIK & PETER SPRICK (2013) Morphology and identification of the pupae of several species of soil-dwelling broad-nosed weevils from Central Europe (Coleoptera, Curculionidae, Entiminae). Zootaxa, 3731(4): 445-472. Zootaxa 3745 (2): 299-300, DOI: http://dx.doi.org/10.11646/zootaxa.3745.2.

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

The mature larva of the weevil species Orobitis cyanea (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 Viola canina L. (Violaceae), and feeding holes were observed on V. riviniana Rchb. Adults of Orobitis cyanea 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 Leiosoma cribrum (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 Orobitis cyanea are discussed in regard to the systematic position of this taxon