Plateumaris bracata (Scopoli, 1772)

Geiser, Elisabeth, 2023, Revision of the Palaearctic species of the genus Plateumaris C. G. Thomson, 1859 (Coleoptera, Chrysomelidae, Donaciinae), ZooKeys 1177, pp. 167-233 : 167

Plateumaris bracata (Scopoli, 1772)

Fig. 4

Prionus bracatus Scopoli, 1772: 100.

Donacia abdominalis Olivier, 1800: 9.

Plateumaris bracatus var. fairmairi LeGrand, 1861a: 265.

Donacia nigra Fabricius, 1792: 117.

Donacia palustris Herbst, 1784: 100.

Leptura violacea Pallas, 1773: 724.

Type locality.

Plateumaris bracatus : Carniola, a historical region which comprised parts of present-day Slovenia.

Type material.

Type specimens of P. bracatus do not exist anymore. Sadly, Scopoli’s collection of insects from Carniola decayed during his life time. He committed this collection to a printer in Vienna who apparently did not store it adequately. Before all the pictures were printed, Scopoli complained in his 1773 letter to Linnaeus ( Brelih et al. 2006) that the insects "had either decayed or fallen apart".

Taxonomic history and synonymies.

In nearly all publications the species name has been misspelled " Plateumaris braccata ". The spelling in the original description by Scopoli (1772) is " Prionus Bracatus" with a single “c” ( Geiser and Geiser 2023). Scopoli used this epithet presumably because “bracae” means “trousers” or “pants” referring to the clubbed shape of the metafemora. A variant of this word exists in later medieval Latin and was spelled “braccae”, which Schenkling (1917) used in his explanation of the scientific names of beetles. Because the spelling of the original description is linguistically correct it must be preserved unaltered (ICZN, Art. 32.2.1). Because the original description by Scopoli is very short, Weise (1893) published a more detailed redescription (see Geiser and Geiser 2023).

Donacia abdominalis (Olivier, 1800): Silfverberg (2010) cited this synonym as Donacia abdominalis (Olivier, 1795). Despite the title page dated 1795, the fourth volume of Olivier’s 'Entomologie, ou histoire naturelle des insectes’ was issued in two parts, one probably in 1795 and the second one in 1800. All new taxa made available in this work have previously been dated 1795 in the literature ( Bousquet 2018). In any case, Olivier’s volume does not contain the original description. He also listed another name of this species, Leptura violacea Pallas, and then described the typical characters of P. bracata . Later, P. abdominalis was regarded synonymous with P. rustica because it was mixed up with P. abdominalis Bedel, 1891, who intentionally did not describe it as a new species (see section on P. rustica for details).

Plateumaris fairmairi was first described by LeGrand (1861a) on page 265 as variation of Donacia nigra (see Geiser and Geiser 2023) from a specimen with complete black antennae and legs. The often-mentioned page 89 derives from the reprint ( LeGrand 1861b).

Fabricius described Donacia nigra by 1792 (see Geiser and Geiser 2023). He allocated it close to D. festucae which is now synonymous with P. sericea . The name Plateumaris was not established then, but Fabricius (1792) noticed some differences from other Donacia species.

Diagnosis.

This is the largest Plateumaris species, body length: 8.0-12.0 mm (Fig. 4A ).

Head, pronotum and elytra entirely black or with a weak blue, purple or green metallic lustre, antennae and legs reddish brown in most specimens, elytra elongate, ~ 2 × as long as wide, side contour of the elytra very straight, almost parallel.

Description.

Size: 8.0-12.0 mm.

Colour: Dark, entirely black or at the most with weak blue, purple or green metallic lustre.

Head: Entirely black or with weak metallic lustre. Fine punctures and very fine wrinkles. Antennae minimum as long as the half length of the beetle, basal part of the antennomere always reddish (with rare exceptions), apical part dark; ½ A1 ≥ A2, ½ A3 ≥ A2, A4 ≥ A3, A1 ≈ A4, A5 … A11 ≈ A4.

Pronotum: Cordate, ahead distinctly wider than behind, anterior tubercles only slightly convex, slightly pubescent. Disc with fine punctures, median line well developed, sometimes shortened, but also very shallow and almost invisible in some specimens.

Elytra: Base of elytra with short, distinct setae in most specimens, elytral disc rugose, punctures delicate, not deep, interstices strongly transversely wrinkled; contour of the margin very straight, almost parallel; elytra elongate, ~ 2 × as long as wide, ratio of length to width = (1.8-2.1): 1.

Legs: Colour variation from complete reddish brown to dark apical parts and completely dark legs, femora basally very broad, metafemur with broad tooth, robust in male, in female feeble or indistinct.

Aedeagus: see Fig. 4B .

Similar species.

The most similar species is Plateumaris consimilis , which is smaller (6.0-9.2 mm) on average, its elytra are shorter with a ratio of length to width ≤ 1.8, and the outer contour of the elytra are slightly rounded, not parallel.

Biology.

Plateumaris bracata is monophagous on Phragmites australis (Cav.) Trin. ex Steud., the common reed, Poaceae ( Bieńkowski 2014). The beetle can be found concealed in the Phragmites leaf-folds. When feeding, it penetrates the young leaf shoots which later unfold to present a characteristic transverse series of round holes. Donacia clavipes feeds on the same plant species in a similar fashion but, in this case, the series of holes produced are irregularly elongated ( Menzies and Cox 1996; Rheinheimer and Hassler 2018). For identification of the larvae see Steinhausen (1994) and Bieńkowski and Orlova-Bieńkowskaja (2004). Despite its large distribution area and its common food plant, its number of specimens stored in museum collections is always remarkably fewer than the number of P. consimilis or P. sericea . Compared with Donacia clavipes , which occurs on the same food plant, the numbers of P. bracata specimens are also much fewer. Recent records are extremely rare.

Distribution.

All parts of Europe except southern Europe and north Scandinavia, continuing to central Asia, including southern parts of Russia and western Siberia. Records exist for Europe: Austria, Belgium, Bosnia-Herzegovina [new in PalCat], Belarus, Bulgaria, Croatia [first record], Czech Republic, Denmark, Estonia, Finland, France, Germany, Great Britain, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Moldavia, Montenegro [first record], The Netherlands, Norway, Poland, Romania, Russia (central and south parts of European Russia), Serbia [new in PalCat], Slovakia, Slovenia, Sweden, Switzerland, Ukraine.

Asia: Azerbaijan, China (Xinjiang [first record]), Georgia, Iran [new in PalCat], Kazakhstan, Kyrgyzstan [new in PalCat], Russia (south Siberia [new in PalCat], west Siberia).

New country records additional to Silfverberg (2010).

Bosnia-Herzegovina: Mohr (1966b).

Croatia • 3 ex.; Dalmatia; E. Geiser 2019 det.; coll. Frey in NHMB.

Montenegro • 2 ex.; Montenegro; E. Geiser 2019 det.; coll. Frey in NHMB.

Serbia: Gavrilović and Ćurčić (2011) and Mohr (1966b).

China • 2 ex.; Xinjiang, "Ost-Turkestan, Bagratsch-Kul" [Bosten-Lake], Kurla; May 1902; Hauser leg.; E. Geiser 2019 det.; HNHM • 1 ex.; Xinjiang, Kuldscha province, Upper Ili valley ["Ober Jli-Thal"]; 1897; F. Hauser leg.; " Pl. braccata " H. Goecke 1956 det., E. Geiser 2019 vid.; coll. Frey in NHMB. Note: Bosten-Lake lies east of Kurla; Kuldscha is now called Yining (in Chinese). Both Bosten-Lake and Kuldscha are located in north-western Xinjiang, on the northern side of the Ili River in the Dzungarian basin, ~ 70 km east of the border with Kazakhstan.

Iran • 2 ex.; Khorasan-e Razavi province, Sabzevar; 36°12′N, 57°35′E; 1024 m a.s.l.; 23. Aug 2012 ( Samin 2018).

Kyrgyzstan: Bieńkowski (2014).

Russia: South Siberia ( Gus’kova et al. 2018).

Material examined.

More than 100 specimens from different localities throughout the distribution area.

Figures

Figure 4. Plateumaris bracata A habitus B aedeagus (photographs by K. Matsumoto) C elytra D elytra of Plateumaris consimilis (drawings from Mohr 1966 a). Scale bar: one unit - 1 mm.