Paenelimnoecus sp.

Van Den Hoek Ostende, Lars W., Casanovas-Vilar, Isaac & Furió, Marc, 2020, Stuck in the middle. A geographical appraisal of the oldest insectivores - and a marsupial - from the Vallès-Penedès Basin (early Miocene, Catalonia, Spain), Comptes Rendus Palevol 19 (1), pp. 1-25 : 18

Paenelimnoecus sp.

( Fig. 5 P-R)

MATERIAL AND MEASUREMENTS (in cm).— Spain. Escletxes del Papiol ,1 P4 sin, IPS86422 , 0.97 × 0.91; 2 m1 sin., IPS86425 -26, 0.92 × 0.55; 0.95 × 0.51; 1 m2 dext. in ramus, IPS86424 , 0.93 × 0.55 .

DESCRIPTION

P4

The premolar is just somewhat longer than wide. The front part of the paracone is steep, leaving a wide space with the parastyle. The latter is somewhat larger than the protocone, which is situated lingually of the parastyle.A hypocone cannot be recognized. The lingual side stands at a low angle to the labial side; the cingulum of the posterior emargination covers the labial half but it is absent close to the lingual margin.

m1

The trigonid is clearly longer and slightly wider than the talonid. The metaconid lies posterolingually of the protoconid, shaping, in combination with the long paralophid, a very open trigonid basin. The oblique cristid ends labially to the middle of the posterior wall of the trigonid. The hypolophid is missing. The cusps of the talonid are damaged in one of the two specimens. In the other, the entoconid is missing but a very low barrier (?entocristid) borders the talonid basin lingually. The anterior cingulid is strong, the posterior cingulid is well developed. There is a narrow cingulid on the labial side, but the cingulum appears to be missing on the lingual side.

m2

The only available specimen is somewhat damaged. It closely resembles the m1, but the talonid and trigonid are of similar length and the trigonid basin is less open.

REMARKS

The most prominent character of the molars from Escletxes del Papiol is the reduced entoconid. This feature is characteristic for the genus Paenelimnoecus , many of the more advanced representatives of which even lose the entoconid altogether. A less reduced entoconid-entocristid complex is still present in the central European early Miocene species P.micromorphus ( Doben-Florin 1964; Ziegler 1989; Klietmann et al. 2014c) and in P. truyolsi , a species known from the middle Miocene of the Calatayud-Montalban Basin ( Van den Hoek Ostende et al. 2009). The two species are very close in morphology, mainly differing in the morphology of the p4, an element not found in the Vallès-Penedès assemblages. Comparison with the material of P. truyolsi from the inland localities shows that there are some small differences with that material. Notably, the Catalan molars are somewhat smaller than the sample from Aragón. The lower molars actually fit well with the P. micromorphus assemblage from the German fissure Petersbuch 28 ( Klietmann et al. 2014c), but the P4 is smaller than that from the German locality. Notably, Paenelimnoecus has not been encountered in Ramblian deposits of the Daroca-Montalbán basin, even though the faunas of the Ramblian type section have been extensively studied (Van den Hoek Ostende 2003). The classification of the genus Paenelimnoecus has been a bone of contention for mammal palaeontologists for many years (for discussion seeKlietmann et al. 2014c). The solution we advocated in Van den Hoek Ostende et al. (2009), placing the genus in the Allosoricinae , seems now a poor choice. At that time, we already noted that the position of “ Sorex ” gracilidens , was one of the major issues to be resolved. In the meantime, Hugueney et al. (2012) erected a new genus, Viretia , within the Allosoricinae for that late early and middle Miocene species. Given the vast morphological differences between Paenelimnoecus and Viretia , placement within the Allosoricinae for the former is indeed not tenable. Van den Hoek Ostende et al. (2009: 2003) already suggested: “Should [Paenelimnoeucs and Allosorex ] be shown not to represent a single clade, the clear roots in the Crocidosoricinae would be better expressed by placing Paenelimnoecus in a separate tribe within that subfamily, rather than creating a monotypic subfamily for it.” Although this classification as such is new, it is actually combing the views of Ziegler (1989) as Crocidosoricinae and Fejfar et al. (2006) as Paenelimnoecinae into one hierarchic solution. Notably, this solution would allow for a crocidosoricine stock that has a more advanced morphology of the p4 as the one currently considered typical for the subfamily, as was already advocated by Furió et al. (2007) for some genera.