Anchonidium selvanum sp. nov. (Coleoptera, Curculionidae, Molytinae) from northern Portugal

The fourth species of Anchonidium sensu stricto from Western Europe is described, photographed and compared with its congeners; an updated key of the genus is given. The habitat in the northern mountain chains in Portugal in the native Quercus mountain forests is characterized and illustrated

We here focus on a new species of Anchonidium s. str.from northern Portugal, morphologically most closely re lated to Anchonidium spathiferum Germann, 2020 from Serra do Estrela.Germann (2020) already assumed that four specimens from Serra do Marão might belong to a new species.A collecting excursion into the northern mountain chains in Portugal finally allowed to study the variability of the new species, and helped understanding of the distri bution patterns of A. unguiculare and A. selvanum sp.nov.

Material and methods
We provide the description of the new species in a con densed form.For details, we refer to the exhaustive re description of the genus sensu stricto by Germann (2020).Main emphasis is set on the illustrating photos taken with a Keyence VHX-6000 photosystem at the Naturhis torisches Museum Basel (NMB).Photos of the genita lia were taken from objects embedded in glycerol.Body length was measured dorsally from the anterior margin of the pronotum to the apex of elytra.
For the collection methodology of specimens, all de tails are given in Germann (2020).Label data for all spec imens are printed.All type specimens are labelled with red printed name labels.Locality data for the map was taken from Germann (2020).

Discussion
The distribution of the four Anchonidium s. str.species in Portugal follows the mountain chains and river valleys (Fig. 17   Serras Peneda and Gerez, but reaches also the Serra do Barroso (two sampled localities: 10 km NE Cabeceiras de Basto, 41°35'26"N, 7°56'12"W, and 11 km NE Cabecei ras de Basto, 41°35'45"N, 7°56'26"W), and even crosses the Rio Tâmega valley.In the northernmost edge of the Serra do Alvão, we collected A. unguiculare from scru bland at the following locality: 1 km northeast of Macieira, 41°25'53"N, 7°48'34"W, 970 m a.s.l.just four kilometers north of the type locality of the new species.Hence, we did not directly observe a sympatric occurrence, but it is likely.
Due to the constant loss of its characteristic habitat, Anchonidium selvanum sp.nov.must be considered as threatened.The relict character of those forests and the new species is of special importance, and we need to address this observation here.These ancient oak forests are tiny relicts of a habitat type, which had a much wider distribution in ancient times; surely these forests covered a considerable part of those mountain chains.Neverthe less, due to exceptionally redundant wildfires in Portugal (Nunes and Duarte 2006), and a severe loss of natural hab itats due to overexploitation followed by plantations of the abovementioned Australian trees, which even enhance the chance of severe wildfires, this habitat type strongly declined.Even in the Parque Natural do Alvão, we found only small remains of this ancient forest type.Anchonidium selvanum sp.nov.has to be considered as an excellent indicator for these ancient woodlands.We observed spec tacular differences in individual numbers collected, when comparing disturbed habitats with more intact ones.
The observed ecological demands of the Anchonidium s. str.species investigated differ to a certain extent.We col lected all species under humid and shaded conditions.A. unguiculare accepts larger varieties of forests, from med iterranean Oak forests in the south of Spain and in Mo rocco, to the oceanic influenced deciduous forests along the Atlantic coast of Spain, France and Great Britain. A. braunerti seems to be restricted to the highest elevations of Serra de Monchique in a habitat type where heather and mosses dominate nowadays.We collected A. spathiferum in a very similar habitat, where, however, the absence of an ancient Oak forest might explain the rareness of specimens found.Here, with the discovery of A. selvanum sp.nov. it is obvious that this new species is restricted to the an cient Oak forests, and as we could show with specifically prospected localities, the more northern situated mountain chains are populated by A. unguiculare.The latter species also occurred in much larger numbers in more ancient fo rests, rather comparable with A. selvanum sp.nov.
). Anchonidium braunerti in the most southern Serra de Monchique on 890 m a.s.l. with the Rio Tajo as the northern barrier.A. spathiferum in the Serra da Estre la on 1290 m a.s.l. with the Douro valley in between the hereby described A. selvanum sp.nov. in both, the Ser ra do Marão and Serra do Alvão on 750-1180 m a.s.l.The specific excursions into the most northern Serras re vealed that A. unguiculare is not only distributed in the

Figure 15 .
Figure 15.Habitat at type locality of A. selvanum sp.nov. at Bobal, 880 m a.s.l., Serra do Alvão.A small remaining part of the ancient Oak forest with mosses, lichens and a deep leaf litter layer at ground where the new species lives in remarkable den sities (Photo: C. Braunert).

Figure 16 .
Figure 16.Remains and replantation of Oak forest in the Serra do Marão close to Ansiães.A good example for small remains of the ancient forests where we found only few individuals of A. selvanum sp.nov.(Photo: C. Braunert).