Strophosoma

Gosik, Rafał & Sprick, Peter, 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), pp. 445-472 : 462

Strophosoma c.f. sus Stephens, 1831

( Figs 9 , 19 , 49–51 , 72–73 )

Material. 2 ♀♀ collected on 0 9.07.2012 and 1 ♀ on 0 2.09. 2012 in Berkhof in the north of Hannover; exactly at the same locality and sampling site as in Brachyderes incanus ( Figs 72–73 ).

On the identity of the pupa: at the collecting locality 2 Strophosoma species were present as aduls, S. capitatum (DeGeer, 1775) and S. sus Stephens, 1831 . Both were found in medium numbers; furthermore a single specimen of S. fulvicorne Walton, 1846 was collected at a sampling site 260 m away. S. fulvicorne and S. sus are confined to Calluna vulgaris , whereas S. capitatum is a very polyphagous species.

By comparing the shape of rostrum and pronotum of pupa with adult specimens of S. capitatum and S. sus the former species was excluded.

General morphology. Body length up to: 4.60 mm (♀), width at the level of mesocoxae: 2.75 mm (♀), head width: 1.5 mm (♀). Body rather stout, slightly curved, whitish. Cuticle smooth. Rostrum short, almost 1.1 as long as wide, surpassing procoxae in repose. Antennae elongate and slender. Pronotum almost 1.6 as wide as long. Ab. I–VII almost of equal length; Ab. VIII semicircular; Ab. IX distinctly smaller than previous ones. Pseudocerci conical, slightly elongate. Five pairs of functional spiracles placed laterally on Ab. I–V.

Chaetotaxy. Setae short or very short, hair-like, without curved apical part, brown, only on abdominal tergites based on small protuberances. Rostrum with a pair of es, 2 pairs of rs1-2; head capsule bearing 1 pair of vs, 3 pairs of sos1-3 and a pair of os. Es, rs2 and sos3 distinctly shorter than other setae. Pronotum with a pair of as1, 3 pairs of sls1- 3, and paired ls1-2, ds1-2 and pls1-2. All pronotal setae almost equal in length. Meso- and metathorax each with 4 pairs of short setae (d1-4). Tergal part of Ab. I–V each with 6 pairs of d1-6, different in length, arranged posteriorly in three groups (d1, d2-4, d5-6) and 2 l1-2, located near the tergum-sternum border. Ab. VI–VII each with 6 pairs of d1-6, almost equal in length, located posteriorly in regular lines, a pair of setae (d0) placed antero-medially and 2 l1-2, located near the tergum-sternum border. Ab. VIII with 5 pairs of long d1-5, located posteriorly or antero-medially, and 2 pairs of l1-2. Ab. IX with 2 pairs of short d1-2 and 3 pairs of v1-3. Abdominal setae and their protuberances increasing gradually from Ab. I to VIII. Each apex of femora with 2 hair-like setae (fes1-2), different in length.

Figures

FIGURES 1 – 10. Weevils (adults, dorsal view): 1 — Barypeithes pellucidus; 2 — Brachyderes incanus; 3 — Liophloeus tessulatus; 4 — Otiorhynchus dieckmanni; 5 — O. tenebricosus form lugdunensis; 6 — Peritelus sphaeroides; 7 — Phyllobius pyri s. l.; 8 — P. intrusus; 9 — Strophosoma c. f. sus; 10 — Tanymecus palliatus (photos: P. Sprick).

FIGURES 11 – 20. Pupae (ventral view): 11 — Barypeithes pellucidus; 12 — Brachyderes incanus; 13 — Liophloeus tessulatus; 14 — Otiorhynchus dieckmanni; 15 — O. tenebricosus form lugdunensis; 16 — Peritelus sphaeroides; 17 — Phyllobius pyri; 18 — P. intrusus; 19 — Strophosoma c. f. sus; 20 — Tanymecus palliatus (photos: R. Gosik).

FIGURES 49 – 51. Strophosoma c. f. sus (pupa, habitus and chaetotaxy): 49 — ventral view; 50 — lateral view; 51 — dorsal view (abbreviations: es — epistomal setae, rs — rostral s., os — orbital s., sos — superorbital s., vs — vertical s., as — apical s., ls — lateral s., sls – superlateral s., ds — discal s., pls — posterolateral s., fes — femoral s., d — dorsal s., l — lateral s., v — ventral s., pcpseudocerci).

FIGURES 72 – 77. Sampling sites of pupae or mature larvae (reared to pupae) of field-collected species. 72 and 73 — sampling site and habitat of Brachyderes incanus and Strophosoma c. f. sus larvae or pupae near Berkhof (09.07., 02.09.2012): a sand pit with naturally grown Calluna and Pinus vegetation; 74 — sampling site of mature larvae of Phyllobius intrusus under Chamaecyparis obtusa ‘ Crippsii’ in a tree nursery in Bad Zwischenahn, 29.03.2011; 75 — sampling site of a pupa of Phyllobius pyri s. str. at the border of Helstorf peat bog, 21.04.2012; 76 — sampling site of Barypeithes pellucidus pupae: a bed of Bergenia cordifolia ‘ Admiral’ in a garden near Hildesheim, 06.04.2011; 77 — sampling site of a Tanymecus palliatus pupa in a Medicago sativa field near Cottbus on fly ash soil, 0 9.08. 2011 (photos: P. Sprick).