Glyptolenus Bates, 1878

Traces, Pierre Moret, 2024, Description of new Platynini from the montane cloud forest of Ecuador, with a redefinition of the genera Glyptolenus Bates and Glyptolenoides Perrault (Coleoptera, Carabidae), Faunitaxys 12 (63), pp. 1-23 : 10-12

Glyptolenus Bates, 1878

Glyptolenus Bates, 1878: 595 .

Glyptolenus Bates : Whitehead, 1974: 123; Perrault, 1991: 44; Liebherr, 1997: 90; Moret, 1999: 294; Will & Liebherr, 2002: 60; Moret & Murienne, 2020: 9.

Sculpturia Straneo : Will & Liebherr, 2002: 59 (synonymy).

Type species: Glyptolenus rugicollis Bates, 1878 , by monotypy.

Taxonomic remarks. – Glyptolenus Bates , as redefined by Whitehead (1974: 123), comprises platynine species with anterior tibia dorsally canaliculate and male genitalia basally melanistic (especially the base of the parameres). Perrault added three characters to this diagnosis: submentum quadrisetose, fourth protarsomere bilobate, and bursa copulatrix without a dense band of lumenal microtrichia ( Perrault 1991: 44). Furthermore, Perrault split Glyptolenus into two genera, based on the form and setation of the fourth metatarsomere (MTT4). He left in Glyptolenus the species with a dense brush of setae covering the ventral surface of MTT4, and moved to a new genus, Glyptolenoides , the species with two parallel rows of fewer and stronger setae on the ventral face of the same article ( Perrault 1991: 47). This separation, accepted in Moret (1999) and Will & Liebherr (2002), was based on only one character: the ventral setation of MTT4.

However, an ongoing integrative taxonomic study ( Moret & Murienne 2020 and unpublished data) shows that the tarsal setation pattern is highly variable in Glyptolenus and that the two-rowed character state (Fig. 11b-c) coexists with the brush-like character state (Fig. 10b-c) in different species groups that are firmly supported by other characters, especially those of the female genitalia. The morphology of MTT4 thus appears to have been subject of convergent evolutions in several clades of the Glyptolenus complex. Consequently, including all the species exhibiting a two-rowed MTT4 setation pattern in the genus Glyptolenoides would make it polyphyletic. According to a preliminary phylogenetic analysis based on the COI marker ( Moret & Murienne, 2020: 9), Glyptolenoides can only be accepted as a monophyletic taxon if it is limited to the type species, G. azureus ( Chaudoir, 1859) , and a few related species which, in addition to the two-rowed condition of MTT4, exhibit asymmetric tarsomeres ( Fig. 14 b-c) and a distinctive female genitalic pattern ( Fig. 9 f-g).

In view of the pending revision of these two genera, we thought it would be useful to describe several species that illustrate the morphological variability of Glyptolenus and Glyptolenoides . A preliminary diagnosis of both genera is given below. The undifferentiation of the spermatheca’s basal duct ( Fig. 9 f-g) and the asymmetry of MTT1–3, due to an oblique cut of the outer side of the article ( Fig. 14 b-c), are the principal synapomorphies that characterize Glyptolenoides . Conversely, the dorsal sculpture of the tibiae, the melanistic base of the parameres and the transformation of tarsal trichoid sensilla into translucent, flattened a. Glyptolenus rugicollis Bates, 1878 . b. D Glyptolenus calvus sp. nov. c. Glyptolenus arboricola sp. nov. d. Glyptolenus resbecqi sp. nov. e. Glyptolenus hector sp. nov. f. Glyptolenoides azureus Chaudoir, 1859 . g. Glyptolenoides formicarius sp. nov.

strips on the apical lobes of PT4 and MST4 ( Deuve 2019) are characters shared by Glyptolenus and Glyptolenoides .

Diagnosis of Glyptolenus Bates, 1878 . – Submentum quadrisetose. Pro- and mesotibiae dorsally canaliculate, or sulcate, or simply flattened. MTT4 variable, bilobed or not, ventrally with two rows of setae (Fig. 11b-c) or with a dense cover of unordered setae (Fig. 10b-c); apical lobes of PT4 and MST4 with long and more or less spatuliform hyaline phanera ( Deuve 2019); apex of MTT4 with variable hyaline phanera on the outer lobe, and with or without hyaline setae on the inner lobe. Sides of MTT1–3 symmetric. Male genitalia diorchid; median lobe of the aedeagus and parameres basally melanistic (Fig. 10d-e and 12c-d). Bursa copulatrix conical or cylindrical, with or without lumenal microtrichia ( Fig. 9 a-e); spermatheca elongate, tubular, rarely bipartite ( G. chalybaeus ( Dejean, 1831) , see Liebherr, 1997: 94); basal duct of the spermatheca very variable in length, from shorter than the spermatheca ( G. arboricola sp. nov., Fig. 9c) to ca. 10 times longer ( G. rugicollis Bates, 1878 , type species, Fig. 9a), but always distinct and forming an angle with the spermatheca ( Fig. 9 a-e).

N. B. The protibial and mesotibial extra furrow of Glyptolenus and Glyptolenoides is located on the dorsal face of the tibia ( Perrault 1991, Deuve 2019). Referring to it as “external” ( Whitehead 1974, Liebherr 1997, Will & Liebherr 2002) is less accurate. The canaliculate structure of this furrow (i.e., a sulcus delimited laterally by two sharp, elevated ridges) is more consistent on the mesotibiae than on the protibiae. In some species the sculpture of the dorsal face of the protibiae is almost completely obsolete (e.g. hereafter Glyptolenus hector sp. nov.), whereas the mesotibiae exhibit a distinct groove. The epithets canaliculate, sulcate and flattened correspond to different states of erosion of this character.