Hedychridium, Abeille de Perrin, 1878

Rosa, Paolo, Heim, René & Bernasconi, Marco Valerio, 2022, The Palaearctic types of Chrysididae (Insecta, Hymenoptera) deposited in the Linsenmaier collection. Part 2. Elampini: genus Hedychridium Abeille de Perrin, 1878, Zootaxa 5090 (1), pp. 1-94 : 82-84

The genus Hedychridium in Linsenmaier’s systematics

Linsenmaier subdivided the Palaearctic species of the genus Hedychridium in four subgenera and fiveteen species groups. In the first revision of the West Palaearctic species, Linsenmaier (1959a) proposed three subgenera: Hedychridium s.str., Acrotoma Mocsáry, 1902b and Hexachrydium Bischoff, 1913 (correct spelling: Hexachridium). The name Acrotoma Mocsáry, 1902b is objectively unavailabe because it is a junior homonym of Acrotoma Boettger, 1881 (Mollusca, Clausiliidae ) ( Kimsey & Bohart 1991). However, Linsenmaier (1999) continued to use it as valid subgeneric name. Linsenmaier (1959a) considered Buyssonia Mocsáry, 1902b and Wollmannia Mocsáry, 1909 as synonyms of Acrotoma and Tetrachrydium Zimmermann, 1952 synonym of Hexachridium. Only later, Linsenmaier (1968) correctly recognised Wollmannia as a subgenus of Hedychrum Latreille, 1802 , after receiving a specimen in exchange from Nikol’skaya.

Linsenmaier (1959a) firstly established two species groups: H. roseum group and H. sculpturatum group. Afterward, Linsenmaier (1968) provided the first classification of the species groups and established the following ones: H. luteipenne group, H. planifrons group, H. postthoracicum group, H. plagiatum group, H. ardens group, H. monochroum group (= Cyrteuchridium Semenov-Tian-Shanskij, 1954), H. incrassatum group (= Zarudnium Semenov-Tian-Shanskij, 1954, Zarudnidium Semenov-Tian-Shanskij, 1954, Cyrteuchrum Semenov-Tian-Shanskij, 1954), H. margaritaceum (= Irenula Semenov-Tian-Shanskij & Nikol’skaya, 1954), H. flavipes group (= Colpopyga Semenov-Tian-Shanskij, 1954), H. roseum group (= Euchrum Semenov-Tian-Shanskij, 1954), H. sculpturatum group (= Euchrum Semenov-Tian-Shanskij, 1954). In the same publication, Linsenmaier (1968) described the subgenus Prochridium . Some years later, Linsenmaier (1994) established the H. semenovi group, and then (1997) the H. anale and H. heliophilum groups. Finally, some changes were proposed by Linsenmaier (1999), namely the description of the H. luteum group and H. modestum group, and the union of some groups: H. ardens-monochroum group and H. roseum-sculpturatum group. If the formation of the first group was unnecessary and not supported by any morphological or molecular analyses, the establishment of the H. roseum-sculpturatum group was a new step forward a better classification, since members of the H. roseum group subsequently proved to be females (with nonmetallic abdomen) and males (with metallic abdomen included in the H. sculpturatum group) of the same species ( Rosa 2003; Arens 2004a).

Linsenmaier’s classification (1959a, 1959b, 1968, 1969, 1987, 1993, 1994, 1997, 1999) for the Palaearctic species is here syntethised.

Genus Hedychridium Abeille de Perrin, 1878

Subgenus Prochridium Linsenmaier, 1968

Subgenus Hedychridium s. str.

modestum group

planifrons group

plagiatum group luteum group

ardens-monochroum group

coriaceum group

anale group

heliophilum group

incrassatum group

flavipes group

elongatum group

margaritaceum group

roseum - sculpturatum group

Subgenus Acrotoma Mocsáry, 1902b

Subgenus Hexachridium Bischoff, 1913

Remarks. The H. planifrons group was renamed attenuatum group by Kimsey & Bohart (1991) and later H. wroughtoni group by Strumia (1999), because Hedychridium wroughtoni du Buysson, 1896 is the first species described in the species group.