Psalidognathus incas Thomson, 1859

Santos-Silva, Antonio & Spooner, Amoret, 2021, On some species of Psalidognathus Gray, especially those of the group “ superbus ” (Coleoptera, Cerambycidae, Prioninae), Zootaxa 5023 (3), pp. 389-404 : 398-399

On Psalidognathus incas Thomson, 1859 , and P. limenius Erichson, 1847

Psalidognathus Limenius Erichson, 1847: 139 .

Psalidognathus Incas Thomson, 1859b: 41 .

Erichson (1847) described P. limenius as follows (translated): “ Psalidognathus violaceus, shiny, front [vertex] distinctly bicarinate, labium bifid.—Length “1’’ 7’’’–2’’ 2’’’ [it is not possible to be exact because it is not possible to know which line system he was following (there are many: French, Austrian, Bavarian, Danish, etc.); using the Bavarian ones, the specimens measured from about 39.6 mm to about 54.8 mm].” Evidently, this description does not allow recognizing the species, as commented by Thomson (1859b). In fact, it does not allow separating it from P. friendii because all features pointed by him are present in the original description of this species. We are surprised that Thomson (1959b) had, in our opinion, correctly supposed that his P. incas was equal to P. limenius (“? Limenius, Éricshson [sic], Arch. de Wieg, 1847, p. 139. Species insufficiently described to be recognized” [translated]). Even so, some considerations are needed:

1. Gemminger (1872: 2754) considered P. incas as a junior synonym of P. limenius ; this synonymy, apparently, was based more on supposition than on real facts;

2. Although Thomson (1859b) knew the description of P. superbus (this because he worked on P. modestus , a species described in the same work by Fries), he simply ignored the existence of the species in the revision of the genus;

3. Thomson (1877a: 254) reported (translated): “According Mr. Henry Deyrolle, the type of P. friendii would be identical with P. Incas Thoms. However, M. Gray said formally that the typical specimen from your description is metallic green with violaceous reflections, which has nothing to do with the P. incas, Thoms. ” The original description of P. friendii reported the color as “of a metallic green, tinted with purple; the antennae and legs of a metallic purple.” This description, without doubt is not true because only the head and the pronotum are metallic green tinted with purple. The elytra are distinctly violaceous. This, apparently, conducted Thomson to a wrong interpretation. Even so, Thomson’s arguments make no sense, especially because he knew that the species of the genus are often very variable in color (in the immediately preceding part, he had named the chromatic variations in P. friendii );

4. Thomson (1877a), arguing that the description of P. limenius was insufficient, synonymized this species under P. incas . Evidently, this argument, although coherent, cannot be accepted. Thus, P. incas has always been the true junior synonym of P. limenius .

5. The designation of lectotype by Quentin & Villiers (1983) has no nomenclatural value because two lectotypes were designated at the same time.