Metallesthes subpilosa Nonfried, 1891

Moeseneder, Christian H., Hutchinson, Paul M. & Lambkin, Christine L., 2014, Revision of the genus Metallesthes Kraatz and description of Metallesthes anneliesae, a new species of Cetoniinae (Coleoptera: Scarabaeidae) from Queensland and New South Wales, Australia, Zootaxa 3881 (4), pp. 301-327 : 319-326

Metallesthes subpilosa Nonfried, 1891

When Nonfried (1891) described M. subpilosa ( Fig. 5 ) he provided German and Latin descriptions of the species. Some of the characters described, however, differ between the two texts; in particular the descriptions of colours are often contradictory. We provide here a translation of the German text (by CHM) with those cases where the Latin differs in square brackets.

“Elongate, convex, black-green [brown] with bronze [metallic] reflections; ventrally shiny copper [brownblack], sparsely pilose. Entirely different from Metall. metallescens White due to its elongate form and different sculpture. Clypeus quadrate, subparallel, feebly indented, lateral margins steeply elevated, roughly punctured, black. Antenna brown. Thorax round, strongly convex, deeply incised before scutellum, with rounded lateral corners, densely granulate, shiny black-green [with copper reflexes]. Scutellum with same colour, shiny, [triangular, acute,] rough shallow punctured, with very smooth, shiny, calous midline. Humeral umbones not raised, shiny. Elytra parallel, strongly convex, with elevated, smooth suture and costae, intervals densely punctured [rugulose], [saturated brown metallic,] with long red-brown pilosity. Pygidium, dashed, [bronze, smooth] without pilosity. Ventrally green with copper reflexes [metallic brown, punctate,] sparse brown [red] pilosity. Metasternum and coxae dashed. [Legs slender, black, sparsely punctate.] Tibiae roughly punctured, dark black-brown, with row of setae. Protibiae tridentate, mesotibiae bidentate, metatibiae with single, large, blunt denticle. Length 14 mm. Origin: Queensland, New Guinea.”

Nonfried’s (1891) description of M. subpilosa is of a beetle unlike any other Metallesthes species. The author himself writes that it is “Entirely different from Metall. metallescens due to its elongated form and different sculpture”.

Metallesthes subpilosa was listed in all major works that dealt with Australian cetoniines ( Lea 1914, Schenkling 1921, Cassis & Weir 1992, Allard 1995, Calder 2002, Krajcik 2012). Allard (1995) illustrated and described a cetoniine that he considered to be M. subpilosa . None of the few characters he provided agree with Nonfried’s original description and only a dorsal view with obscured legs was included. The illustrated specimen ( Allard 1995: plate 17, fig. 12) appears to be a specimen of M. unicolor . Since this specimen cannot be located, and no label data or deposition was provided, we cannot verify the information.

Type specimens of Metallesthes subpilosa . According to Horn et al. (1990) the cetoniines in Nonfried’s collection were passed on to Julius Moser and from him to the Zoological Museum Berlin ( ZMB, now MNHUB) in 1926. We contacted the MNHUB with a request concerning type material of Nonfried’s M. subpilosa . Joachim Willers at the MNHUB confirmed that Nonfried’s cetoniines should reside in their collection and conducted several unsuccessful searches between 2011 and 2014. In 2014 we re-examined the description of Metallesthes subpilosa and found it to be very similar with Pseudoclithira ruficornis . We sent a new request to the MNHUB and received images of two specimens from the Nonfried collection, which we believe were seen by Nonfried and which we consider to constitute the type series of M. subpilosa .

FIGURES 9–10. 9—Totals (n) and proportions of collected specimens per sex (P m, P f) of Metallesthes species. 10—Seasonal occurrence of Metallesthes species. Males—black bars, females—white bars, unsexed—grey bars. Specimens collected or observed (variable vertical scale) per month (horizontal scale) per species and sex.

One female specimen ( Fig. 5 ) bears labels with the text “ Metallesthes hirsuta Nfr Type / Pseudoclithria ruficornis (Westw) [female symbol] M.E. Bacchus det. 1969 / Coll. Nonfried. Australia.” and displays all the characters in Nonfried’s description of M. subpilosa . We herewith designate this specimen as lectotype of Metallesthes subpilosa Nonfried, 1891 and attached a label with the text “ LECTOTYPE / Metallesthes / subpilosa / Nonfried, 1891 / labelled by MNHUB 2014” to it. The condition of this specimen is fair; tarsomeres 2–5 and claws are missing on both prolegs, claws are missing on the left metaleg and one claw is missing on the right metaleg.

A second specimen exists in the collection of the MNHUB that may have been seen by Nonfried. It is a male and carries two labels with the text “Nonfried 89 ex Australia septentr. / Pseudoclithria [male symbol] ruficornis (Westw) M.E. Bacchus det. 1969”. While there is no evidence that Nonfried considered it to also be “ Metallesthes hirsuta ” it is clear that he was aware of the specimen at least one year before he described the taxon. Therefore, we consider this specimen to be a paralectotype. The condition of this specimen is fair; tarsomeres 3–5 and claws are missing on the right mesoleg and the right metaleg and tarsomere 2–5 and claws are missing on the left metaleg.

We designate the lectotype of M. subpilosa in accordance with International Commission on Zoological Nomenclature’s Recommendation 74G which stipulates that designation of lectotypes are to be done in revisionary taxonomic work to enhance the stability of nomenclature. While the name “ hirsuta ” on the possible type specimen and the published name of the species, “ subpilosa ”, are not the same, we consider that they refer to the same taxon because 1) the specimens match the description of M. subpilosa and no other known Australian cetoniines or Papua New Guinea cetoniine genera 2) Nonfried assigned the assumed type specimen to the genus Metallesthes , 3) Nonfried described M. subpilosa as being entirely different than any other Metallesthes and that applies to the two specimens, 4) he did not publish any other papers on the genus, 5) the specimens were located in Nonfried’s collection, where they were expected, 6) both names refer to pilosity, 7) the paralectotype’s location “ex Australia septentr[ional]” indicates that it was found in northern Australia which is consistent with the distribution of M.

subpilosa which Nonfried notes as Queensland and New Guinea, and 8) it not uncommon for an author to consider several names for an undescribed species.

Synonymy of Metallesthes subpilosa . Nonfried’s inclusion of Metallesthes subpilosa in the genus Metallesthes was doubtful ( Nonfried 1891). Lea (1914) also held doubts about M. subpilosa and noted that “The description of this species reads as if founded upon an insect similar to nigrans and hirticeps, and so possibly it should be transferred to Pseudoclithria .” After inspecting specimens of P. ruficornis in the collections AM, PMH, QM, SAM, and MNHUB we determined that the female specimen bearing a Nonfried type label found in the collection of the MNHUB designated herein as the lectotype of Metallesthes subpilosa Nonfried, 1891 and the M. subpilosa paralectotype specimen were both Pseudoclithria ruficornis Westwood, 1874 , and therefore we herein synonymise M. subpilosa with P. ruficornis . While M. subpilosa was described from Queensland and New Guinea, Pseudoclithria ruficornis is known to occur in Western Australia, South Australia, and Victoria. (a revision of the genus Pseudoclithria by CHM and PMH is in preparation and will deal with the species in detail). Another male specimen of P. ruficornis exists in the MNHUB, which was deposited in the same tray as the lectotype and paralectotype of M. subpilosa at the time when we examined images of it. The collection label is illegible and there is no evidence that Nonfried had seen this specimen.

Figures

FIGURE 5. Metallesthes subpilosa female lectotype as “ Metallesthes hirsuta ” (MNHUB), new synonym of Pseudoclithira ruficornis. Images by Joachim Willers (MNHUB).