Pantomallus proletarius

Pantomallus proletarius (Erichson, 1847) Figs 47, 48, 49, 50, 51, 52, 53 Eburia proletaria Erichson, 1847: 140. Eburia bauri Linell, 1899: 260. Syn. nov. Remarks. Linell (1899) described Eburia bauri (Figs 49–53) based on two males and three females from Chatham Island (= Isla de San Cristóbal) in Ecuador (Galapagos). According to him, the elytra in males have the “ apices acuminate and spinose at middle, without sutural spines, ” and the femora are “ not spinose. ” However, he described the elytra in females as having the “ apices truncate, with long spines, the sutural spine half as long as the exterior one, ” and the “ middle and posterior femora with a long apical spine on the inner side. ” These sexual dimorphisms were not known in other species of Eburia sensu auctorum (Coeleburia) or in Pantomallus Lacordaire, 1868. Van Dyke (1953) synonymized Eburia bauri with Eburia proletaria (currently, Pantomallus proletarius) and reported, “ Elytra … emarginate and bispinose at apex, the sutural spines the shorter, ” and “ The California Academy of Sciences has four specimens collected by F. X. Williams, including a typical male from Chatham Island, collected in February 1906, which was carefully compared with specimens in the British Museum of Natural History. This served as the basis of the description above. ” The description of the elytral apex of the males examined by Van Dyke (1953) does not agree with that by Blair (1933), who examined two males of Eburia proletaria collected in the Galapagos Islands and reported no morphological differences between them; therefore, we assume that both specimens have a similar elytral apex. However, as Blair (1933) described the elytral apex in females as in the males from the same island collected by F. X. Williams, it is possible that the lectotype and paralectotype males were aberrant specimens. However, without examining all those specimens, it is not possible to affirm whether all belong to a single variable species or whether two species occur on Chatham Island. Gilmour (1966) removed Eburia bauri from the synonymy of Eburia proletaria (= Pantomallus proletarius) and synonymized it with Eburia pilosa: “ The opportunity of examining and comparing the four specimens from the Galapagos Islands, collected by F. X. Williams, in the California Academy of Sciences collections, has enabled me to synonymize [sic] Eburia bauri Linell with E. pilosa Erichson, not with E. proletaria Erichson, as has been previously stated by various authors. ” Despite our doubts about the identity of the Galapagos specimens identified as Eburia pilosa, especially from Chatham Island (currently San Cristóbal), which includes the three female paralectotypes, we can state that the synonymy proposed by Gilmour (1966) was a mistake. This is because the holotype of Eburia bauri has procoxal cavities strongly angulated laterally, which leaves no doubt that it belongs to Pantomallus. The specimens of Stenocorus pilosus (= Eburia pilosa) from Peru have the procoxal cavities closed laterally (males and females), which places the species in Coeleburia (Eburia sensu auctorum). Furthermore, the lectotype of Eburia bauri does not have abundant erect setae on the legs and ventral surface of the body, whereas they are very abundant in both sexes of the true Coeleburia pilosa. Additionally, although Gilmour (1966) did not describe the shape of the dorsal surface of the scape in the male lectotype of Stenocorus pilosus (he limited himself to describing the general shape of the scape: “ scape moderately clavate ”), it is possible to see in the photograph presented by him that it is distinctly sulcate. In the lectotype of Eburia bauri, it is not clavate and not sulcate dorsally. On the other hand, as with Van Dyke (1953), we were unable to find any reliable difference that would allow the separation of Eburia bauri from Pantomallus proletarius. The elytral apex in P. proletarius is quite variable in the specimens we studied (eight specimens, males and females) and may bear a spine on the external apical angle and / or on the sutural angle or be completely unarmed or nearly so (Fig. 47). Another minor difference found is the length of the more inner ivory-colored band on the base of the elytra, which is always distinctly shorter in the specimens examined by us than in the lectotype of E. bauri. However, we believe that this feature is also variable in P. proletarius, especially since the length in the lectotype female of E. proletarius (see photographs in Bezark 2025 and in Gilmour 1966) is intermediate between that of the lectotype of E. bauri and the specimens we examined. Therefore, we synonymize Eburia bauri with Pantomallus proletarius.