Neoxorides collaris

Neoxorides collaris (Gravenhorst, 1829)

Figs 4B, 5D, 6A, C, E, 7B, D, 9A, D

Xorides collaris Gravenhorst, 1829: 848–849.

Xorides collaris var. harpii Fahringer, 1935 in Schimitschek 1935: 139.

Neoxorides collaris – Clément 1938: 517–518. — Oehlke 1966: 890–891, fig. 4. — Kasparyan 1981: 94. — Kanders 2009: 9. — Varga 2015: 3–4, figs 1, 4.

Xorides collaris – Ratzeburg 1848: 105. — Holmgren 1860: 65. — Dalla Torre 1901 –1902: 381–382. — Schmiedeknecht 1907: 17; 1908: 1368. — Hellén 1915: 20. — Haupt 1917: 82.

Diagnosis

This species has proven notoriously difficult to identify with previous keys, and we here give a detailed diagnosis to clarify how it is distinct from other species of the genus. Neoxorides collaris is a species that is quite variable in size with a fore wing length of 8–12 mm. The metasoma in the female is stout with the first tergite about 1.7–1.9 times as long as wide. The ovipositor is relatively short and stout, curved upwards and usually about as long as the metasoma minus the first tergite. The female has the lateral part of pronotum with irregularly punctate rugose structure only in the upper half, while the lower half is polished without microsculpture (Fig. 5D). If the central part occasionally has weak striae, they never extend into the upper part backwards /upwards as in N. montanus and N. striatus sp. nov. (Fig. 5G). The mesopleural furrow usually lacks any distinct transverse carinae and if carinae are present, they are usually less distinct and denser (Figs 4B, 6E). The colouration of the fore coxae ranges from orange, sometimes with the basal half infuscate, to having the apical part more or less extensively yellow. The mid coxae are usually entirely orange in the females, thereby differing from the largely yellow apices of the mid-coxae in the female of N. montanus. The female is distinguished from N. nitens and N. opacus by the combination of the unmodified pronotal collar, the weakly aciculate dorsal portion of the propodeum (Fig. 6A) and the tergites, as well as the aciculate/shagreened mesopleuron/mesosternum with weak, but clearly discernible punctures (Fig. 4B). Neoxorides collaris is distinguished from N. varipes by the orange or partly orange hind coxae and the absence of reticulate microsculpture on the sides of the pronotum. The female is distinguished from N. montanus by the shorter and upcurved ovipositor, the usually stouter first tergite, the structure and the narrower white line on the sides of pronotum, and in most cases by the shape of the pale markings along the inner orbits above the antennal scrobes, which are narrower and have more parallel inner sides (Fig. 9A). The most useful character when separating the males of N. collaris and N. montanus seems to be the relative length of the metasoma, usually expressed in the shape of the first tergite. In N. montanus, it is usually longer, about 3.0–3.5 times as long as wide, while it is about 2.5 times as long as wide in N. collaris. In small males of N. collaris, the hind coxa in the male is apically/dorsally more or less infuscate and the hind femur is at least dorsally infuscate. The weak infuscation of the hind femur dorsally is evident also in Scandinavian females. Frequently, the entire hind femur in the male is brownish with a reddish ring basally. The hind trochanter and trochantelli in the male are usually dark brown dorsally and white ventrally. In Nordic specimens, the mid coxae are largely yellow on the outer side in N. montanus, while they are entirely orange, rarely with a small yellowish spot, in N. collaris. From N. striatus sp. nov., N. collaris is distinguished by the evenly shagreened frons, the structure of the pronotum, the absence of transverse carinae in the mesopleural furrow (Fig. 6E), the wider face in the male (as in Fig. 9G) and the stouter metasoma (Fig. 9D).

Material examined

Lectotype

POLAND • ♂; NMWU.

Other material

SWEDEN • 12 ♀♀, 7 ♂♂; NHRS, UPSZ, MZLU, NJ, LW.

GERMANY • 1 ♂; MR.

FINLAND • 3 ♀♀, 1 ♂; MZH.

FRANCE • 1 ♀, 3 ♂♂; NHMUK.

UKRAINE • 1 ♀; OV.

Ecology

Neoxorides collaris is connected to cerambycids feeding on conifers. Most specimens have been collected in coniferous forests dominated by scots pine Pinus sylvestris L. or on scots pine timber (first author pers. obs.).

Distribution and status in Sweden

Neoxorides collaris occurs over most of the country, especially in light forests with dead wood or in burned forests. Ha, Hs, Sm, Sö, Up, Vb, Ög.

Remarks

Some of the distinguishing characters previously used to separate this species from N. montanus, such as the shape of the male genitalia and the shape of the basal flagellomeres in the female, appear partly unreliable. However, the species is usually easily distinguished by the characters listed in the key and the diagnosis. The type of N. collaris var. harpii (Fahringer, 1935 in Schimitschek 1935) is lost (Horstmann 1988). The original description (p. 139) refers to a rearing from Rhagium inquisitor (Linnaeus, 1758) and mentions characters that could be attributed to several species of Neoxorides. With the current level of knowledge, this variety cannot be properly interpreted and we chose the more conservative point of view and follow the synonymy proposed by the original author.

DNA barcode

The barcodes of Neoxorides collaris are separated from their closest barcodes (in N. opacus) by at least 7.0% p-distance. The sequences are available on GenBank under accession numbers: MT 072689 (SK19_39), MT 072690 (SK19_40), MT 072694 (SK_2148), MT 072693 (SK19_36).