Nama

Meregalli, Massimo, Borovec, Roman, Cervella, Piero, Santovito, Alfredo, Toševski, Ivo, Ottati, Sara & Nakládal, Oto, 2021, The Namaini, a new weevil tribe with six new genera from South Africa (Coleoptera: Curculionidae: Entiminae), Zoological Journal of the Linnean Society 193, pp. 95-123 : 101-102

THE NAMA -GROUP RELATIONSHIPS IN THE ENTIMINAE

The species of the Nama -group cluster in a clade distinct from all other Entiminae and no relationships with taxa of other tribes of Entiminae were found. The tribal classification of the subfamily Entiminae is still debated, and even its monophyly seems questionable ( McKenna et al., 2009; Gillett et al., 2014, 2018). The tribes, as presently defined ( Alonso-Zarazaga & Lyal, 1999), can be used only in a historical, traditional sense, and do not represent the evolutionary structure of the subfamily. Relationships among the tribes is contrasting in papers dealing with the Curculionoidea ( McKenna et al., 2009; Haran et al., 2013; Gillett et al., 2014). In particular, Gillett et al. (2018) demonstrated that most of the tribes, in their present composition, are para- or polyphyletic. Most of the South African genera were referred to tribes native to the Palaearctic region without a critical analysis of the characters. One of the most important attempts at a reclassification of the Afrotropical entimines was by Marshall (1942). Based on chaetotaxy of the mandibles, he split entimines with “otiorhynchine”- type antennal scrobes (scrobes entirely visible in dorsal view, in profile not forming narrow furrow mostly directed downwards) into two main groups: a group with the mandible bearing only three setae and a group where the mandible bears more or less numerous setae. This mandible chaetotaxy seems to reflect relationships and is still used today, for example, for the redefinition of the tribe Embrithini ( Borovec & Oberprieler, 2013) . Using this character, the Afrotropical entimines with “otiorhynchine”- type scrobes, lacking laterally prominent humeral calli and having trisetose mandibles, were included in the tribes Embrithini , Oosomini , “ Peritelini ” and “ Trachyphloeini ”, even though the attribution of the Afrotropical genera to the latter two tribes is questionable. A detailed discussion and a differential diagnosis of the Namaini vs. the other Afrotropical entimine tribes is given in the Remarks section of the treatment of the tribe.

Since the mt-Cox1 analysis shows that no close relationships exist between the Nama -group and any of the other tribes of Entiminae —as defined by their typegenus—of which mt-Cox1 sequences were available, the Nama -group is here assigned to a new tribe, the Namaini .

PHYLOGENETIC LINEAGES IN THE TRIBE NAMAINI

Our study reveals that the tribe Namaini includes seven monophyletic units, each used to define genus-rank taxa.

The two main subclades, Subclade A and Subclade B, that compose the Namaini clade, might suggest that the tribe is composed of two distinct subtribes. However, the second subclade has no statistical support, and indeed the affinities of Pentamerica could not be determined. Therefore, a subdivision of the tribe into subtribes is not justified. The two genera composing the first group of Subclade A have maximal support and are clearly well delimited by molecular sequences, with some molecular and morphological synapomorphies. The taxa included in each of the two genera are morphologically uniform, with a p-distance usually around 0.09–0.10. Therefore, the attribution of the taxa whose sequences were not available to Cervellaea or Namaquania was relatively easy. The relationships of Nama with Yamalaka , the two genera composing the second groups of Subclade A, are sound. Both genera are composed of relatively well-differentiated taxa, both in their morphology and mt-Cox1 sequences, with a p-distance of about 0.15. The remaining genera appear to be isolated and their reciprocal relationships could not be clearly disclosed.

The placement of Pentamerica is uncertain, since no sound evidence correlating it to either of the two subclades was obtained, neither by the Bayesian inference (associating it to Subclade B, but only with 30% pp) nor by the Bayes factor (associating it to Subclade A, but with BF = 2). The molecular sequences confirm this uncertainty, with the nucleotides of some sites shared with taxa of Nama (Subclade A) and those of other sites shared with taxa of Springbokia (Subclade B) . Springbokia is clearly defined by morphology and mt-Cox1 sequences; the p-distances among the taxa vary between 0.10 and 0.15. Finally, four of the taxa that cluster in Cedebergia appear to be reciprocally closely related, also based on their morphology, while the other species, 601, is more isolated, also geographically.

In the present paper the new tribe and the new genera corresponding to these monophyletic units are described. Due to the complexity of the Namaini and the large number of new species, only the type species of each new genus are be described here. The other taxa of the various genera are listed with their locality code and their formal descriptions will be the subject of further papers.

In the taxonomic part of the paper only the main diagnosis of all the new taxa have been reported. The detailed morphological descriptions of each taxon, the discussions on the reciprocal relationships and the differential diagnoses are added in Supporting Information, File S1.

TAXONOMY