Otiorhynchus

Rafał Gosik, Peter Sprick, Jiří Skuhrovec, Magdalena Deruś & Martin Hommes, 2016, 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, Zootaxa 4108 (1), pp. 1-67 : 26-29

Otiorhynchus (s. str.) aurifer Boheman, 1843

Material examined: 11 larvae ( Figs. 211 , 226 ). JKI, Braunschweig, breeding with Ligustrum ovalifolium Hassk. and Viburnum tinus L. flowerpots ( Fig. 224 ), 0 5.01.2012, 7 ex.; some pots were transferred then to Hannover, CURCI, for regular pupae search. 1 larva was taken out from a flowerpot with L. ovalifolium on 16.01.2012 and another ex. on 27.01.2012. A second attempt with 80 first instar larvae was started on 24.08.2012 with Ligustrum ovalifolium and L. vulgare (2 flowerpots each) in the JKI and revealed 2 ex. on 10.01.2013.

Additional material: another 8 mature larvae (and 1 pupa) from the second breeding attempt had already been obtained on 14.12.2012.

Remarks about breeding and development. Larvae were exclusively obtained from two breeding attempts in the climate chamber of the JKI in Braunschweig. In September and October a large number of eggs and some dozens of first instar larvae were released on 4 flowerpots with Ligustrum ovalifolium (2 pots) and Viburnum tinus (2 pots). The parents of these eggs were collected on 0 6.09. 2011 in Heilbronn, former south station, close to “Alter Kaiser”, from Viburnum tinus and Ligustrum vulgare at roadside plantations and front garden hedgerows. This occurrence was discovered a few months before by Klaus Schrameyer and the first record in Baden-Württemberg ( Schrameyer & Bernau 2011). The first mature larvae were obtained in the beginning of January 2012 (05.01.). In Germany, this species of Mediterranean origin is known to occur only in two regions (cities of Hamburg and Heilbronn).

Apparently there is no paper that deals with the life-cycle of this species. These data could be a first contribution on the bionomics of Otiorhynchus aurifer . In 2011, breeding was started on 21.09., but only with 8 L l larvae, the majority of larvae, over 100, were released on the plants on 28.10.2011. This is more exact than reported before in Gosik & Sprick (2012a). 6 pupae were obtained on 27.01.2012 and again 6 from 0 9.02. during February 2012. In 2012, breeding was started on 24.08. and revealed the first mature larvae and 1 pupa mid-December. Therefore, the time required to receive pupae from L l larvae was 3–4 months under controlled conditions in the lab, and—opposite to several other [Central European] species—no diapause or developmental delay was observed.

In Baden-Württemberg, this species was introduced with Laurus nobilis L. very likely in 2003 to Heilbronn- Horkheim, and in 2008 it was found on wayside plantations and front garden hedgerows with Ligustrum vulgare and Viburnum tinus in the southern part of the city ( Schrameyer & Bernau 2011). The origin of the Laurus plants was Italy. Yunakov & Nazarenko (2003) reported about the first record in Ukraine in the town of Sevastopol (Crimea) in 1951, and in Jalta this species was found on Laurus, Rosa and in the botanical garden Nikita nearby on Olea . Heijerman & Drost (2000) reported about the first finding in The Netherlands in 1999 on different bushes, and Crovetti (1971) about an occurrence as noxious species in Sardinia on Citrus .

Description ( Figs. 67–77 ).

Coloration. Head dark yellow; all thoracic and abdominal segments from yellow to dark yellow.

Body elongated ( Fig. 67 ). Chaetotaxy: Setae different in length, relatively short, filiform. Thorax. Prothorax with 4 long and 5 medium long to short prns and 2 ps, different in length. Mesothorax with 1 short prs, 4 pds (ordered: 2 short and 2 long), 1 long as, 1 long eps and 1 long ps. Chaetotaxy of meso- and metathorax similar. Each pedal area of thoracic segments well isolated, with 4 pda, different in length. Each thoracic segment with 1 short eus ( Fig. 68 ). Abdomen. Abdominal segments I–VIII with 1 short prs, 5 pds (ordered: 2 short, 1 long, 1 short and 1 long), 1 long and 1 minute sps [abd. seg. VIII only with 1 microseta], 2 eps, different in length, 1 long and 1 very short ps, 1 long lsts and 2 eus ( Figs. 69, 71, 72 ). Abdominal segment IX with 3 ds, different in length, 2 ps, different in length and 2 sts, equal in length ( Figs. 70–72 ). Lateral lobes of abdominal segment X with 1–2 minute ts each.

Head subglobose, narrowed bilaterally ( Fig. 73 ). Head capsule with 4 medium long des, des 1 and des 2 placed on central part of epicranium, des 3 located on frontal suture, des 5 located anterolaterally; 2 medium long fs, fs 4 placed anteromedially, fs 5 located near to antenna; 2 medium long les; and 1 medium long ves. Stemmata (1 pair) feebly visible. Antennal segment membranous, bearing 1 conical sensorium and 3–4 filiform sensilla. Clypeus 3.3 times as wide as long with 1 short cls, placed posterolaterally ( Fig. 74 ). Labrum about 2 times as wide as long with 3 straight lms of different length, placed medially or mediolaterally; lms 2 distinctly longer than other setae, all lms exceeding the outline of the labrum; the anterior margin of labrum almost rounded ( Fig. 74 ). Epipharynx with 3 finger-like als, different in length; 3 ams, different in length, one ams similar in shape to mes, but the position is more to ams; and 2 very short mes (see comments about ams and mes in Material and Methods); labral rods (lr) elongated, strong convergent ( Fig. 75 ). Mandible ( Fig. 76 ) bifid, teeth almost of equal height; with 2 mds, different in length; internal edge with a triangular tooth. Maxilla ( Fig. 77 ) with 1 very long stps and 2 very long pfs, placed ventrolaterally; without mbs. Mala with 4 dms, different in length and 3 straight vms, almost equal in length. Maxillary palpi with two palpomeres of almost equal length; basal palpomere with 1 mxps; distal palpomere with a group of 5 conical, cuticular processes apically; each palpomere with a sensillum. Praelabium heart-shaped ( Fig. 77 ), with 1 very short ligs and 1 very long prms. Labial palpi with two palpomeres, relatively elongated; both palpomeres almost equal in length. Praemental sclerite well visible. Postlabium with 3 pms, different in length; pms 2 very long, 5 times as long as pms 1 and pms 3 ( Fig. 77 ).

Differential diagnosis. See “Key to larvae of selected Otiorhynchus species” and Tables 1, 2.

Figures

FIGURES 211 – 219. Mature larva, lateral view. 211 — O. aurifer, 212 — O. meridionalis, 213 — O. clavipes (= O. tenebricosus), 214 — O. fuscipes (= O. tenebricosus), 215 — O. lugdunensis, 216 — O. salicicola, 217 — O. ovatus, 218 — O. crataegi, 219 — O. rugosostriatus. (Photos by R. Gosik).

FIGURES 226 – 231. Breeding and collecting of the weevil larvae. 226 — O. aurifer larvae from breeding in the climate chamber, 227 — O. crataegi larva and pupa in the field—size compared with a Taxus needle, 228 — O. rugosostriatus larva in the Panicum virgatum field in Wiesbaden-Schierstein, 229 — O. rugosostriatus, young adult, just hatched, found under Panicum virgatum, as before, 230 — O. armatus, 2 mature larvae on graph paper, 231 — O. armadillo larva in a flowerpot used for breeding. (Photos by P. Sprick).

FIGURES 220 – 225. Breeding and collecting of the weevil larvae. 220, 222 — Sampling sites of O. crataegi under Taxus in Bad Zwischenahn, 221 — Breeding of O. armadillo in flowerpots with Euonymus fortunei cultivar Emerald ' n Gold, 223, 225 — Sampling sites of O. rugosostriatus under Panicum virgatum in Wiesbaden-Schierstein, 224 — Breeding of O. aurifer in a flowerpot with Viburnum tinus. (Photos by P. Sprick).

FIGURES 67 – 72. Otiorhynchus aurifer; mature larva. 67 — habitus, lateral view, 68 — lateral view of thoracic segments, 69 — lateral view of abdominal segment I, 70 — lateral view of abdominal segments VIII – IX, 71 — ventral view of abdominal segments VIII – X, 72 — dorsal view of abdominal segments VIII – X. Abbreviations: Ab. — abdominal segment, Th. — thoracic s., I – X—number of segments, prns — pronotal seta (e), prs — prodorsal s., pds — postdorsal s., pda — pedal s., as — alar s., lsts — laterosternal s., eus — eusternal s., ps — pleural s., sps — spiracular s., sts — sternal s., ds — dorsal s., ts — terminal s.

FIGURES 73 – 77. Otiorhynchus aurifer; mature larva and mouthparts. 73 — dorsal view of head, 74 — labrum and clypeus, 75 — epipharynx, 76 — left mandible, 77 — maxillo-labial complex. Abbreviations: des — dorsoepicranial seta (e), fs — frontal s., les — lateroepicranial s., ves — ventroepicranial s., at—antenna, st—stemmata, cls — clypeal s., lms — labral s., ams — anteromedial s., als — anterolateral s., mes — medial s., lr—labral rods, mds — mandible dorsal s., dms — dorsal malae s., vms — ventral malae s., mxps — maxillary palps s., pfs — palpiferal s., stps — stipal s., mbs — mandible basiventral s., prms — prelabial s., pms — postlabial s., ligs — ligular s.