Griburius tredecimpunctatus Suffr. D. Sassi 2024, comb. nov.
Creators: name: Sassi, Davide
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Chrysomelidae
Griburius
Griburius tredecimpunctatus

description: Griburius tredecimpunctatus (Suffrian, 1866) comb. nov.
(Figs 8; 11e; 13b)
Metallactus 13 punctatus Suffrian, 1866: 325.
Metallactus tredecimpunctatus Clavareau, 1913: 94 (catalogue); Blackwelder, 1946: 641 (catalogue).
= Scolochrus incomparabilis Suffrian, 1866: 95; Burmeister, 1877: 65; Clavareau, 1913: 90 [Griburius] (catalogue); Blackwelder, 1946: 640 [Griburius] (catalogue). Syn. nov.
Types. In the original description (Suffrian, 1866) the author did not report the number of the specimens of Griburius tredecimpunctatus available for the study, but he pointed out that they all were males. It was possible to trace down four syntypes in BMNH (2), in NMV (1) and in MNHUB (1). The typification was made as follows, in order to stabilize the epithet. LECTOTYPE (by present designation): (MNHUB) 1♂, pinned // “23983” [white label, printed] // “13 punctatus Suffr. San Joam [sic] del Rey Sellow” [blue label, handwritten] // “ Griburius tredecimpunctatus (Suffrian, 1866) (Metallactus 13 punctatus) LECTOTYPUS D. Sassi des.” [red label, printed] //. The label information and the presence of a single syntype for the lectotype match the registration data from the old catalogue of the MNHUB (“23983. 13-punctatus Suffr.*. 1. St. João d. R. Sello.”. PARALECTOTYPES: (BMNH) 1♂, pinned // “ Metallactus 13punctatus Suffr Brasil ” [white label, printed] // “Type Suffrian Coll. Deyrolle” [white label, printed] //; (BMNH) 1♂, pinned // “a D. Suffrian determinat” [White label, printed] // “Met. 13 punctatus” [White label, handwritten] // “67-56” [White label, printed] // “123” [Blue label, handwritten] // “ SYNTYPE ” [White-blue label, printed] //; (NMV) 1♂, pinned // “N. c. M.” [blue label, handwritten] // “Alte Sammlg. Brasilien ” [white label, printed] //. All paralectotypes were labelled: // “ Griburius tredecimpunctatus (Suffrian, 1866) (Metallactus 13 punctatus) PARALECTOTYPUS D. Sassi des.” [red label, printed] //.
The species was described as belonging to the genus Metallactus, but it clearly belongs to Griburius (at least until the latter genus is redefined and circumscribed through a new, more up-to-date diagnosis based on a careful examination of all the species currently attributed to it).
Regarding G. incomparabilis, in the original description (Suffrian, 1866) the author again did not report the number of the available specimens, but he pointed out that they all were females. It was possible to trace down four syntypes in BMNH (2) and in NMV (2). The typification was made as follows, in order to stabilize the epithet. LECTOTYPE (by present designation): (BMNH) 1♀, pinned // “ Scolochrus incomparabilis Suffr Brasil ” [white label, handwritten] //“Type Suffr.coll Deyrolle” [white label, handwritten] //“Baly Coll.”[white label, printed] //“ Griburius incomparabilis (Suffrian, 1866) (Scolochrus incomparabilis) LECTOTYPUS D. Sassi des.” [red label, printed] // “ Griburius tredecimpunctatus Suffr. D. Sassi det. 2023” [white label, printed] //. PARALECTOTYPES (3): (BMNH) 1♀, pinned // “ Brasil … [unreadable word]” [white label, handwritten] // “incomparabilis m” [blue label, handwritten] // “8” [blue label, handwritten] // “67-56” [white label, printed] // “TYPE” [white label, printed] // “E. Coll. Chevr. t ” [white label, printed] //; (NMV) 2♀, pinned // “ Rio de Janeiro ” [white label, printed] //. All paralectotypes are labelled: // “ Griburius incomparabilis (Suffrian, 1866) (Scolochrus incomparabilis) PARALECTOTYPUS D. Sassi des.” [red label, printed] // “ Griburius tredecimpunctatus Suffr. D. Sassi det. 2023” [white label, printed] //. Furthermore, MNHUB holds three specimens which most likely belong to the type series, in my opinion, but whose data do not correspond satisfactorily with what Suffrian pointed out in the original description. In fact, Suffrian reported specimens from the Berlin Museum collected by “Sello” (Friedrich Sellow) in Collo del Sacramento, while the specimens housed there, labelled with the catalog number “24030”, bear collection data as “ Brasil, v. Olf.” In other cases, for example for the syntypes kept in the Vienna Museum, the non-correspondence can be explained with arguments that I consider valid enough (see for example Sassi, 2019), but in the case of MNHUB, the coincidence between the information attached to the type series of the different species described by Suffrian and what he wrote in the original descriptions, is usually very good. Therefore, it is considered consequent to exclude the Berlin material from the designation of the paralectotypes of the species.
Despite the notable difference in dorsal coloration pattern, a careful evaluation of the specimens’ origins leads to the conclusion that the two entities described as Griburius incomparabilis and Metallactus tredecimpunctatus are actually the female and the male of the same species, respectively. As the male genitalia are more informative, at least in light of the current knowledge of Cryptocephalinae in general, it is considered appropriate to give priority to the name originally attributed to the males, even though such name appears further down in the same work (Suffrian, 1866). Since both names were published simultaneously, the precedence between them cannot be objectively determined, as outlined in Article 24 of the International Code of Zoological Nomenclature (ICZN, 1999). Therefore, I consider my decision justified by the same article (24.2.2. Determination of precedence of names or acts by the First Reviser. If two or more names, different or identical, and based on the same or different types, or two or more nomenclatural acts, are published on the same date in the same or different works, the precedence of the names or acts is fixed by the First Reviser). Consequently, the following synonymy is proposed: Griburius tredecimpunctatus (Suffrian, 1866) = Griburius incomparabilis (Suffrian, 1866) syn. nov.
Type locality. G. tredecimpunctatus: São João del Rei (Minas Gerais, Brazil). G. incomparabilis: “ Brazil ”.
Additional material examined. BRAZIL: Espirito Santo: Domingos Martins, 7.XII.2021 (1, GBIF); “ Esp. Santo ” (3, HNHMB); “ Espirito Santo ” (1, USNMNH). “Brasil” (1, MNHUB); “Bresil” (1, MNHN); “Brazil, Gift of F. C. Bowditch ” (1, USNMNH). “Brasilia” (1, MNHUB).
Additional data from literature. Suffrian (1866), as stated above, reported “Collo del Sagramento” for G. incomparabilis as Brazilian collection locality for part of the syntypes. As previously discussed elsewhere (Sassi, 2019), I am inclined to deem that the toponym must be intended as Colonia del Sacramento (Colonia, Uruguay).
Blackwelder (1877) described two new species from Argentina hinting at G. incomparabilis as the possible closest taxon. As a matter of fact, these new species (G. octoguttatus and G. persimilis) are clearly different and turned out to belong to genus Metallactus (Sassi, 2019).
Distribution. Brazil (Espirito Santo, Minas Gerais), Uruguay.
Diagnosis. The robust silhouette, with a highly transverse pronotum and, above all, the distinctive dorsal coloration featuring seven black spots on the pronotum arranged in two rows, the wide dark elytral spot in females, and, in males, the characteristically elongated small black elytral spots, make this species easily distinguishable from others in the group.
Description of male. Habitus in figs 8a–b (LT). BL = 6.0– 6.5 mm, BW = 3.9–4.4 mm, PL = 1.7–2.1 mm, PW = 3.6–4.0 mm. Interocular distance 8.3–9.2 % of BL.
Head totally black. Labrum light yellow. Head surface covered with punctures and short appressed setosity, denser and coarser on frontoclypeal surface, sparser on vertex. Mid-cranial suture short but well impressed between eyes. Frontoclypeal sutures hardly detectable. Upper lobes of eyes broadly separated from each other. Ocular line slender, strictly adhering to ocular rim up to ocular canthus. Ocular canthus large, rounded, with surface hidden by short, appressed, dense setae. Antennae with first five antennomeres yellowish, reminders brownish. Antennomeres 3–5 bright subcylindrical; 6–11 dull, more flattened and more diffusedly setose.
Pronotum yellow with seven black spots arranged in two lines: four spots along anterior margin, inner ones larger; three spots along posterior margin, outer ones larger, nearly rectangular, mid one just in front of scutellum, small, usually diamond- or teardrop-shaped. Pronotal shape elliptical, markedly transverse and particularly flattened. Lateral margins narrow, scarcely visible from above, regularly curved, with maximum width nearly at middle. Surface moderately shiny with shallow, sparse punctures irregularly distributed across whole pronotal surface. Posterolateral impressions shallow, scarcely oblique.
Scutellum black, trapezoidal. Surface shallowly micropunctured and covered with dense whitish setosity.
Elytron yellow with three black spots, two of them lined along basal margin, longitudinally arranged, third one, lengthened as well, on apical clivus. Elytral outline with sides slightly convergent toward apex. Surface noticeably flattened on disc. Lateral margins narrow, almost invisible from above. Scutellar area fairly raised, so that dorsal profile clearly angular in lateral view. Humeral callus moderately prominent, impunctate. Surface rather shiny with distinctly impressed punctures irregularly arranged anteriorly, with remnants of rows on elytral clivus. Intervals flat. Epipleuron slightly convex, smooth, with surface mostly shiny and impunctate but finely rugulose along margin.
Pygidium totally yellow. Surface matt, covered with shallow punctures and short, appressed, dense setae.
Ventral parts of thorax dark brown to black, with lateral part of hypomera yellowish. Abdominal ventrites brownish, with lighter colouring along sides. Hypomera shiny, almost devoid of punctation, covered with sparse, short setosity. Remainder of ventral part of thorax and abdominal surface matt, with dense, short, regularly distributed whitish setae and fine, shallow, dense punctures. Prosternal process large, with sides almost straight between anterior coxae; apex broadly rounded; surface almost flat and closely but shallowly punctured, covered with long, semi-erect setae. Legs totally black. Sexual dimorphism apparent in anterior leg shape, with femora robust, strengthened and tarsi stocky, thickened.
Median depression on fifth abdominal ventrite shallow, closely covered with short, appressed setae, hardly distinguishable from remainder of ventrite surface. Posterior margin of fifth abdominal ventrite straight. Median lobe of aedeagus (Figs 8k–n) terminated with large, acute triangular apex, tapered anteriorly in lateral view with apex faintly bent ventrally. Setose depressions narrow, shifted on sides, setose only along dorsal margins. Glabrous depressions well delimited, oval-shaped. Aedeagal ventral surface with long, sharp, median carina.
Femal e. BL = 5.8–7.1 mm, BW = 3.9–4.6 mm, PL = 1.7–2.0 mm, PW = 3.7–4.1 mm. Interocular distance 11.3–12.1 % of BL.
Females differ in more elliptical outline, in slightly larger interocular distance and in the anterior legs more typically shaped, with tarsi slenderer. Additionally, the most apparent difference is given by the elytral colour pattern, where a large oval black spot occupies the whole surface, leaving free only the lateral, apical and sutural margins. Sometimes, such spot is chestnut on its central part and black only along the margin, giving rise to a threecoloured pattern (Fig. 8f)
Fifth abdominal ventrite in females with quite large and shallow pit. Bottom of pit glabrous, matt, impunctate but covered by tiny wrinkles. Vasculum of spermatheca (Fig. 11e) scarcely pigmented with slender proximal lobe slightly bent at base. Distal lobe slender as well, long, tapered towards apex which is pointed and mildly bent downward. Ampulla short, not pigmented. Duct insertion and sperm gland insertion perceptibly distinct. Duct uniform in size, slender, coiled with coils rather loose. Insertion on bursa copulatrix simple, not pigmented.
description: Published as part of Sassi, Davide, 2024, Revision of the Griburius posticatus (Suffrian, 1866) species group (Coleoptera: Chrysomelidae: Cryptocephalinae), pp. 201-237 in Zootaxa 5406 (2) on pages 223-226, DOI: 10.11646/zootaxa.5406.2.1, http://zenodo.org/record/10618162