Heterarthrus wuestneii (Konow, 1905)

Liston, Andrew, Mutanen, Marko & Viitasaari, Matti, 2019, On the taxonomy of Heterarthrus (Hymenoptera, Tenthredinidae), with a review of the West Palaearctic species, Journal of Hymenoptera Research 72, pp. 83-126 : 109-111

Heterarthrus wuestneii (Konow, 1905)

Phyllotoma aceris McLachlan, 1867: 104. Syntypes ♀ (probably lost). Type locality: not specified [but probably England: see Healy 1867]. Primary homonym of Phyllotoma aceris Kaltenbach, 1856 [= Heterarthrus leucomela (Klug, 1818)].

Phyllotoma Wüstneii Konow, 1905a: 156. Syntypes ♀, ♂. Lectotype ♂, in SDEI (examined) designated by Muche (1977). Type locality: Denmark, Sonderburg, Insel Alsen.

Heterarthrus imbrosensis W. Schedl, 1981: 151-152. Holotype ♀, in Collection W. Schedl, Innsbruck (examined). Type locality: Greece, Crete, Imbros. Syn. nov.

Heterarthrus tauricus Ermolenko, 1984: 53-56. Holotype ♀, in Schmalhausen Institute, Kiev (not examined). Type locality: Ukraine, Crimea, southern slopes of Al-Petri. Synonymy with wuestneii suggested by Liston (2007) and adopted by Taeger et al. (2010).

Heterarthrus healyi Altenhofer & Zombori, 1987: 191-193. Replacement name for Phyllotoma aceris McLachlan.

Type material examined.

Lectotype Phyllotoma Wüstneii: ♂ "Sonderburg. 12.V.04.", "Coll. Konow", "Eberswalde coll. DEI", " Heterarthrus wüstnei Konow determ. Muche 1976. Mikrosk. Präp. Ty.", “Type”, “GBIF-GISHym3798”, "Paralectotypus Phyllotoma Wüstneii Konow, 1905 des. Zombori 1980", "Paralectotypus ♂ Phyllotoma wuestneii Konow, 1905 des. S. M. Blank 2001", with separate penis valve preparation on glass slide ( Symphyta Coll. Nr: 444, SDEI), SDEI. Paralectotypes: 3♀, 1♂ "Sonderburg. 12.V.04.", and a variety of subsequent labels (SDEI).

Holotype Heterarthrus imbrosensis : ♀ "Kreta: Imbros, Nomos Chania, 6.5.1980, leg. W. Schedl", "Holotypus Heterarthrus imbrosensis Schedl, det. W. Schedl" (Collection W. Schedl, Innsbruck).

Other material examined.

Austria: Upper Austria: 3♂ (DEI-GISHym31987, 31992), Linz , larva ex Acer campestre , 3.6.1977 (em. 4.5.1978), leg. E. Altenhofer (HNHM) . Lower Austria: 1♂ (DEI-GISHym31993), St Pölten, Mine ex Acer campestre , 16.6.1976 (em. 20.4.1977), leg. E. Altenhofer (HNHM) . 2♀ (DEI-GISHym31983), St Pölten, Mine ex Acer campestre , 16.6.1976 (em. 20.4.1977), leg. E. Altenhofer (HNHM) . 1♀ (DEI-GISHym31978), St Poelten , Acer campestre , 16.6.1976 (em. 28.4.1977), leg. E. Altenhofer (HNHM) . 1♀, St Poelten , Acer campestre , 16.6.1976 (em. 27.4.1977), leg. E. Altenhofer (HNHM) . 1♀ (DEI-GISHym31982), St Poelten , Acer campestre , 5.6.1976 (em. 30.4.1977), leg. E. Altenhofer (HNHM) .

Germany: Bavaria: 1♀ (DEI-GISHym19407) 3♂ (DEI-GISHym19408), Franconia, Trimberg, reared ex Acer monspessulanum , 25.05.2003, leg. Liston (SDEI).

Greece: Peleponnese : 7♀ (DEI-GISHym11102) 2♂, Sparti W 6km, Mistrás, 700 m, 13.04.2008, leg. Liston (SDEI) . 1♀, Kalámata SE 15km, Vorio , 650m, 13.04.2008, leg. Liston (SDEI) . 4♀ 1♂ (DEI-GISHym31994), Kastanitsa , 25.04.2015, leg. E. Altenhofer (SDEI) . 3♀ 2♂, Agios Panteleimonas , 23.04.2015, leg. E. Altenhofer (SDEI). Crete : 5♀ (including DEI-GISHym20656) 7♂ ( Liston et al. 2015).

Remarks.

Liston et al. (2015) discussed the taxonomy of H. imbrosensis and wuestneii, pointing out that there is no clear way of separating them morphologically, especially when intermediate specimens from the Peleponnese are taken into account. In any case, the only apparent differences are details of coloration. Greek specimens, especially those from Crete, are usually darker than Central European ones. Neither is the divergence in CO1 barcodes strongly suggestive of the existence of more than one species. Accordingly, we propose the synonymy of H. imbrosensis with H. wuestneii .

The coloration of H. wuestneii varies significantly, even between central European specimens. In females, the malar space can vary from extensively whitish to entirely black, and the supraclypeal area and lower frons may be partly white, or entirely black. The tegula may be entirely white, or only with posterior third whitish.

We have not found any morphological characters which will distinguish H. wuestneii from H. cuneifrons . According to Altenhofer and Zombori (1987), the structure of the frons should be different, but this was not evident in the specimens which we examined. Variability in penis valve morphology is considerable: see also discussion under H. cuneifrons . The form of the penis valve is somewhat different for these species as illustrated by Altenhofer and Zombori (1987, figs 11 and 12). However, the penis valve of the H. wuestneii lectotype ( Fig. 71 ) does not fit very well with either of their drawings, and the penis valve of the reared H. wuestneii specimen illustrated by Liston (2007, fig. 4) looks different from any of these. The drawing of a penis valve of H. wuestneii by Muche (1977), presumably representing the lectotype, which was dissected by Muche and permanently mounted on a glass slide, is very misleading. Only the sclerotised part of the valviceps is outlined; the membranous dorsal part is omitted. We suggest that because of variability, H. cuneifrons and wuestneii males cannot be distinguished by penis valve morphology.

Host plants and biology.

As a result of the synonymy proposed above, H. wuestneii is known to use two different host species: Acer campestre L. ( Altenhofer and Zombori 1987), and A. sempervirens ( Liston et al. 2015). The records from A. monspessulanum L. ( Liston 2007) require confirmation, because the specimens could either belong to H. wuestneii or H. cuneifrons .

Distribution.

Central and southern Europe ( Taeger et al. 2006), including some of the larger Mediterranean Islands (Corsica, Sicily, Crete).

Figures

Figures 69 - 73. Heterarthrus penis valves 69, 70 H. cuneifrons DEI-GISHym 31988, see H. cuneifrons taxon account and Table 1 for details of measurements 71 H. wuestneii lectotype 72 H. wuestneii DEI-GISHym 31987 73 H. wuestneii DEI-GISHym 31993.