Stenobelus tibialis (Blackburn)

Oberprieler, Rolf G., Thompson, Richard T. & Peterson, Magnus, 2010, Darwin’s forgotten weevil, Zootaxa 2675, pp. 33-46 : 37-38

Stenobelus tibialis (Blackburn)

( Figs. 5–6, 8, 10, 13–14)

Belus tibialis Blackburn, 1893: 190–191 , 192 (in key); Lea 1908: 230; 1909a: 197; 1909c: 5; 1917: 597; von Dalla Torre & Voss 1935: 12; Alonso-Zarazaga & Lyal, 1999: 39.

Leptobelus tibialis (Blackburn) : Zimmerman 1991: 58, pl. 29, figs. 1, 2; 1994: 358, fig. 233.

Stenobelus (Stenobelus) tibialis (Blackburn) : Legalov, 2009: 308.

Type locality. not specified but probably Perth , Western Australia (see Zimmerman 1994: 358) .

Diagnosis. SL 7.4–11.2mm in male (n=11), 7.7–10.4mm in female (n=8); pronotum and elytra with distinct white median stripe (vitta) composed of dense setae; setae of dorsal vestiture longer, directed over punctures ( Fig. 8); antennae inserted less than eye diameter in front of eyes; front tibiae with a series of 2–4 spines at distal end of basal emargination ( Fig. 10); tarsites of front tarsi subquadrate, with stout, dicolorous setae (white on outside, black on inside, Figs. 13–14); elytra posteriorly exceeding abdomen by less than length of apical ventrite.

Material examined (30 specimens). Types: tibialis, HT ♀, “ Type [disc with red margin] // Australia / Blackburn Coll. / B.M. 1910-236 [printed] // Belus / tibialis Blackb. [in Blackburn’s hand]” ( BMHN) . Other specimens: 1 ex., Swan River , W.A. ( SAMA) ; 1♂, 8.5km WNW of / Mt. Dale / Western Australia / at 32 o 06’S, 116 o 12’E / 19 November 1989 / M. Peterson // in swampy area / in jarrah forest / at 1415 hrs ( ANIC) ; 1♂, WA / Windy Harbour / 3.XI.1988 / H. & A. Howden ( CMNC) ; 1 ex., S. Australia ( SAMA) ; 1♂, 1♀, “Lucindale, S.A. / A.M. Lea // 47872 / Belus / tibialis Bl. / S. A.; W.A. [in Lea’s hand] // Belus / tibialis / Blackburn / R.T. Thompson det. 1980 / comp. with type [in red ink] // Specimen / figured / ECZ // Leptobelus / tibialis / ( Blackburn ) / det. E.C. Zimmerman ” ( ANIC) ; 2 ex., Lucindale ( SAMA) ; 2♂, 1♀, Lucindale, S.A. / Feuerheerdt ( AMSA, ex A. H. Elston Coll.); 1♀, Kiata , Victoria / Oct. 1928 / F.E. Wilson ( MVMA) ; 4♂, Queensland / Cooloola / 6 Oct. 1979 / G. Kuschel // on swamp plant ( ANIC) ; 2♀, same locality and collector, 5 Oct. 1979 ( ANIC) ; 1♂, Caloundra / 20. 9. [19]58 / M. A. Permiakoff // Leptospermum (UQBA) ; 1♀, Caloundra / Hacker / 28.10.[19]13 ( QMBA) ; 2♀, Searys Creek Rainforest, / via Tin Can Bay, Qld. / 17– 18.x.1970 / G. B. Monteith ( UQBA) ; 1♂, Teewah Creek, via / Tin Can Bay, Qld. / 17–18.x.1970, T. Weir ( ANIC) ; 1♂, same data except: G. B. Monteith ( UQBA) ; 1♂, Camp Milo / Cooloola, S.E Qld. / 15–18.x.1978 / G. B. Monteith ( UQBA) ; 1♀, Currumundi Lakes / Caloundra, Qld. / 30.ix.1972 / G.B. & S.R. Monteith ( ANIC) ; 1♂, Bribie Island, Qld. / 26 Sept 1984 / M.A. Schneider ( UQBA) ; 1♀, same data except: G. Daniels ( UQBA) ; 1♀, Bribie Island , Qld. / Hacker ( QMBA) .

Distribution. South-western Western Australia, eastern South Australia, western Victoria and southern Queensland ( Fig. 15).

Host plants. Adults collected on Astartea fascicularis and Leptospermum (Myrtaceae) and probably Leptocarpus sp. (Restionaceae) ; larval hosts unknown.

Remarks. The card on which the type specimen is mounted bears a black letter ‘T’ at the base, a red ‘A’ above it and the number ‘1774’ in red near the apex ( Fig. 5). The entry in Blackburn’s catalogue under this number reads: “ Belus tibialis Blackb. W.A. (A) 10-12/[18]86”. It seems that ‘A’ may be a regional code; others in W.A. are ‘P’ and ‘G’. Although this species was evidently described from Western Australia, we have only seen 4 specimens from there (including the holotype), and only two of them recent finds. Barely more have been collected in South Australia, seemingly all at Lucindale, where Lea (1917) recorded it as being “fairly common” nearly a century ago. Three of the Lucindale specimens are labelled as having been collected by [B. A.] Feuerheerdt, who lived in Lucindale at the time and may have collected the other four specimens as well. His name appears in several taxonomic revisions as the collector of others insect specimens taken at Lucindale, though always without a date. A single record from western Victoria has come to light, the specimen collected almost as long ago. All other and recently taken specimens are from a small area in coastal south-eastern Queensland ( Fig. 15), which appears to be the only region where the species may still be common. As with S. testaceus , there are no distinct differences between western and eastern Australian specimens, although the aedeagus of the (large, 11.1mm) male from Mt. Dale has a somewhat larger and stouter aedeagus, with a longer tip and the two short, dentate sclerites inside the aedeagal body well separate, not subcontiguous as in specimens from eastern Australia (Lucindale, Cooloola, Tewah Creek).