Mecinus peterharrisi Tosevski & Caldara, 2013

Gosik, Rafal, Skuhrovec, Jiri, Caldara, Roberto & Tosevski, Ivo, 2020, Immature stages of Palearctic Mecinus species (Coleoptera, Curculionidae, Curculioninae): morphological characters diagnostic at genus and species levels, ZooKeys 939, pp. 87-165 : 87

Mecinus peterharrisi Tosevski & Caldara, 2013

Material examined.

25 L3 larvae and 20 pupae, Mecedonia, Prilep, 25.07.2017, (41°17.354'N, 21°29.983'E, 618 m.) ex Linaria dalmatica macedonica , lgt. I. Toševski. Accession numbers of sequenced specimen MN992004.

Description of mature larva

(Figures 34A-D , 35A-F ). Measurements (in mm). Body length: 2.00-3.75. Body width (metathorax and abdominal segments I-II): 0.65-1.00. Head width: 0.35-0.43.

Body (Figure 34A-D ) yellowish, very slender. Chaetotaxy weakly developed, setae extremely short, difficult to observe. Prothorax (Figure 34B ) with nine short prns; two short ps and one short eus. Meso- and metathorax (Figure 34B ) with one short prs, two short pds, one short as, three minute ss, one short eps, one short ps and one short eus. Pedal area with four short pda. Abdominal segments I-VIII (Figure 34C, D ) with one short prs, three short pds arranged along the posterior margin, two minute ss, two short eps, one short ps, one short lsts and two short eus. Abdominal segment IX (Figure 34D ) with two ds located close to the posterior margin, one short ps and two short sts. Each of anal lobe with two minute setae.

Head capsule (Figures 34A , 35A-C ) pale yellow, distinctly narrowed bilaterally. Frontal suture well visible. Des1-3,5 very long, equal in length; des4 three times shorter than other des. Fs1 as long as des1, fs2 and fs3 very short, fs4-5 long. Les1 shorter than les2; two ves and four pes very short (Figure 35A ). Two stemmata of different size. Antennae (Figure 35B ) with sensorium (Se) conical, thrice as long as wide, located medially, and three sensilla of different types: one sa and four sb. Clypeus (Figure 35C ) trapezium-shaped, anterior margin slightly concave; cls2 medium; clss clearly visible. Labrum (Figure 35C ) with sinuate anterior margin; lrs1 very long, lrs2 shorter than lrs1, lrs3 three times shorter than lrs1. Epipharynx (Figure 35D ) with three relatively long, finger-shaped als of almost equal length; two rod-like ams, equal in length; two rod-like mes of medium length; surface smooth; labral rods short, rounded. Mandibles (Figure 35E ) conical, wide, with a small protuberance in the middle of the cutting edge; both mds capilliform, relatively long, equal in length, placed mediolaterally. Maxilla (Figure 35F ) with one stps and two pfs of equal length; mbs very short; mala with six finger-like dms different in length (dms1,2 medium, dms3-6 long to very long), five vms different in length. Maxillary palpi: basal palpomere wider than distal, both of almost equal length. Prelabium (Figure 35F ) close to oval-shaped with one very long prms; ligula with two ligs of equal length; premental sclerite clearly visible, U-shaped. Postlabium (Figure 35F ) with short pms1, long pms2, and short pms3.

Description of pupa

(Figure 36A-C ). Measurements (in mm). Head width: 0.36-0.43. Body width: 0.83-1.50. Body length: 2.46-3.66.

Body elongated, slender, white. Rostrum slender, about five times as long as wide, reaching up to mesocoxae. Antennae slender and moderately elongated. Pronotum 1.1 times as wide as long. Urogomphi (ur) very short, conical, with sclerotised apex, reaching outline of the body, directed downward (Figure 36A, B ).

Chaetotaxy sparse, setae very short, equal in length. Head with one os. Rostrum with one rs placed medially. Setae on head and rostrum straight, as long as those on prothorax (Figure 36A ). Pronotum with one ds, one sls and three pls. Dorsal parts of meso- and metathorax with three setae placed medially. Abdominal segments I-VIII with one seta laterally, two very short setae ventrally and three setae dorsally, placed along posterior margin. Abdominal segment IX with two micro-setae ventrally. (Figure 36B ).

Biological notes.

This species is known only from the southwest region of North Macedonia and northwestern part of Greece following the distribution of Linaria dalmatica macedonica (Griseb.) D.A. Sutton, as well as from sparse populations of L. dalmatica dalmatica (L.) Mill. present at the Montenegrin Sea coast in the vicinity of Kotor Bay ( Toševski et al. 2014). Adults appear in the field at the beginning of March and aggregate on young growing shoots, causing significant damage to the shoot points and apical leaves. Like M. laeviceps , the larvae develop within short larval tunnels, and the newly emerged adults remain and feed in the pupal chamber until mid-August. Adults overwinter in the soil close to the host plant.

Remarks and comparative notes.

This species, found only in the Balkans (Macedonia, Greece, Montenegro) as above reported, is very similar to M. laeviceps , from which it differs by the body being more robust and usually longer, the integument of the pronotum more distinctly bluish, and the penis with longer tip. Moreover, the vestiture is usually formed by slightly broader scales and is therefore generally more distinct. As reported in the remarks on M. heydenii and in the keys, the study of the immatures has revealed other interesting differences between these three species that are very useful for their separation.

Figures

Figure 34. Mecinus peterharrisi mature larva, habitus and chaetotaxy A habitus of the body and frontal view of the head B lateral view of thoracic segments C lateral view of abdominal segment I D lateral view of abdominal segments VII-X. Abbreviations: Th. I-III - number of thoracic segments, Abd. I-X - number of abominal segments, setae: as - alar, ds - dorsal, eps - epipleural, eus - eusternal, lsts - laterosternal, pda - pedal, pds - postdorsal, prns - pronotal, prs - prodorsal, ps - pleural, ss - spiracular, sts - sternal, ts - terminal.

Figure 35. Mecinus peterharrisi mature larva, head and mouth parts A head, frontal view B antenna C clypeus and labrum, dorsal view D epipharynx E left mandible F maxillolabial complex, ventral aspect. Abbreviations: at - antenna, clss - clypeal sensorium, des - dorsal epicranial, lr - labral rods, sa - sensillum ampullaceum, sb - sensillum basiconicum, Se - sensorium, st - stemmata, setae: als - anterolateral, ams - anteromedial, cls - clypeal, dms - dorsal malar, fs - frontal, ligs - ligular, lrs - labral, ls - lateral epicranial, mbs - malar basiventral, mds - mandibular, mes - median, mxps - maxillary palp, pes - postepicranial, ves - ventral, pfs - palpiferal, pms - postlabial, prms - prelabial, stps - stipal, vms - ventral malar.

Figure 36. Mecinus peterharrisi pupa habitus and chaetotaxy A ventral view B lateral view C dorsal view. Abbreviations: Th. I-III - number of thoracic segments, Abd. I-IX - number of abdominal segments, ur - urogomphi, setae: as - apical, d - dorsal, ds - discal, fes - femoral, l - lateral, os - orbital, pls - posterolateral, rs - rostral, sls - superlateral.