Brachyderes incanus (Linnaeus, 1758)

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 : 451

Brachyderes incanus (Linnaeus, 1758)

( Figs 2 , 12 , 25–28 , 58, 59 , 72–73 )

Material. 1 ♂, 0 9.07.2012, Berkhof (Hannover), collected directly in the soil and 2 ♀♀, 14.07. and 22.07.2012. Females were reared from field-collected mature larvae, collected on 0 9.07.2012 at the same locality and sampling site in a sandy soil rooted by Pinus sylvestris L. and Calluna vulgaris (L.) Hull of a naturally forested sand pit inside of a large pine forest area ( Figs 72–73 ).

General morphology. Body length up to: 9.50 mm (♀), 9.60 mm (♂), width at the level of mesocoxae: 5.70 mm (♀), 5.50 mm (♂), head width: 1.80 mm (♀ and ♂). Body slender, elongate, white or yellowish. Cuticle densely covered by minute hair-like cuticular processes ( Fig. 59 ). Rostrum medium-short, almost 1.1 as long as wide, surpassing procoxae in repose. Antennae slender and elongate, clava covered by cuticular thickening. Pronotum almost 1.7 as wide as long. Ab. I–VI of almost equal length; Ab. VII semicircular; next Ab. diminished gradually to the end of the body. Pseudocerci conical, slightly elongate, with sclerotized apical parts ( Fig. 58 ). Sexual dimorphism visible in the structure of Ab. IX: gonotheca of ♀ divided ( Fig. 25 ), of ♂ undivided ( Fig. 26 ). Five pairs of functional spiracles placed laterally on Ab. I–V.

Chaetotaxy. Setae of unequal length, light brown, brown or black, mostly based on small protuberances. Macrosetae of head, rostrum and femora dark brown, with curved apical parts ( Fig. 55 ). Microsetae light brown, straight. Setae on abdominal tergites black, thorn-like. Rostrum with a pair of es, 3 pairs of rs1-3 and 2 pairs of pas1- 2; head capsule bearing 1 pair of vs, 1 pair of os1 and paired sos1-2. Setae pas1, vs, os2 and sos1 long, well visible, with curved apical parts; es, rs1-3, pas2, os1 and sos2 very short, straight. Pronotum with paired as1-2, ds1-2, sls1-2, pls1-2 and a pair of ls, all almost equal in length, straight. Meso- and metathorax each with 5 pairs of short, thorn-like d1-5. Each tergal parts of Ab. I–VIII with 6 pairs of short, thorn-like d1-6, almost equal in length, first pair located medially or antero-medially, next ones located posteriorly in regular lines, 2 pairs of l1-2 located near the tergumsternum border and 3 pairs of very short (poorly visible) v1-3. Ab. IX with 3 pairs of v1-3. Abdominal setae and their protuberances increasing gradually on Ab. I to VIII. Each apex of femora with 2 long setae (fes1-2) with curved apical parts.

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 25 – 28. Brachyderes incanus (pupa, habitus and chaetotaxy): 25 — ventral view of female; 26 — ventral view of male; 27 — dorsal view; 28 — lateral view (abbreviations: es — epistomal setae, rs — rostral s., pas — postantennal s., os — orbital s., sos — superorbital s., vs — vertical s., as — apical s., ls — lateral s., ds — discal s., pls — posterolateral s., fes — femoral s., d — dorsal s., l — lateral s., v — ventral s., pc—pseudocerci).

FIGURES 55 – 63. Setae and microstructure of selected body parts I. Barypeithes pellucidus: 55 – 57 — pseudocerci; Brachyderes incanus: 58 — pseudocerci; 59 — vertical setae; Otiorhynchus tenebricosus form lugdunensis: 60 — vertical s. (with destroyed apical part); 61 — dorsal s., 62 — apical s., 63 — dorsal s. of Ab. VIII (photos: R. Gosik).

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).