Plecotus

Rosina, Valentina V. & Rummel, Michael, 2019, The Early Miocene Bats (Chiroptera, Mammalia) From The Karstic Sites Of Erkertshofen And Petersbuch 2 (Southern Germany), Fossil Imprint 75 (3 - 4), pp. 412-437 : 423

Plecotus cf. atavus TOPÁL, 1987

Text-figs 5a , 6c

M a t e r i a l a n d m e a s u r e m e n t s. Erkertshofen 1:

SNSB-BSPG 1962 XIX 4201, right p4, 0.75 × 0.65. Petersbuch 2: PCMRCh3, left M1, 1.40 × 1.70.

D e s c r i p t i o n a n d c o m p a r i s o n. The molar (specimen PCMRCh3) from Petersbuch 2 is characterised by a closed trigon basin due to the postprotocrista which gradually merges with the postcingulum while the metaloph is absent ( Text-fig. 5a ). Paraconule, paraloph and hypocone are absent. These are typical signs of the upper molars of plecotin bats ( Rosina et al. 2019). The studied M1 differs from the M1 of the late Miocene Barbastella maxima ROSINA, KRUSKOP et SEMENOV, 2019 from Gritsev (MN 9, Ukraine; Rosina et al. 2019) in lacking the meta- and paralophs (Textfig. 5a, f). The cingulum from the distal side of the protocone of this upper molar from Petersbuch 2 is well developed and forms some hypoconal undulation ( Text-fig. 5a ), which makes this fossil form similar to the modern representatives of the modern American genus Corynorphinus ( Text-fig. 5e ). In morphological details, however, the specimen PCMRCh3 is most similar to the upper molars of the representatives of the group P. atavus s. str. from the Miocene localities of Europe ( Text-fig. 5b–d ).

The crown of the p4 (specimen SNSB-BSPG 1962 XIX 4201) from Erkertshofen 1 is shortened, the lingual cingulum is poorly developed and there is an only slightly pronounced anterolingual process of the cingulum. Its anterior root is slightly reduced compared with the posterior. These characters differentiate the p4 from Erkertshofen 1 from Myotis or Submyotodon (compare with Ziegler 2003: 478, fig. 6(1–2)). It is also distinguished from Miostrellus petersbuchensis ROSINA et RUMMEL, 2012 in having a more rounded crown in cross-section, and less developed anterolingual cuspid, as well as in having a reduced first root (compare with Rosina and Rummel 2012: 471, fig. 5E, F). It differs from the р2 of Miniopterus rummelii by a less developed anterolingual cuspid ( Ziegler 2003: 486, fig. 7(1–2)), and in having a shorter protolophid than the buccal cristid ( Text-fig. 6c ). In precisely these characteristics the p4 from Erkertshofen 1 is most similar to the p4 of P. atavus ( Text-fig. 6 ) as well as in size (compare with Rosina et al. 2019: 3, tab. 1). However, the species affiliation of these single fossil teeth from Erkertshofen 1 and Petersbuch 2 could not be confirmed with complete confidence.

Figures

Text-fig. 5. Upper molars of different fossil and recent Plecotini, occlusal view. a – Plecotus cf. atavus, PCMRCh3, left M1, Petersbuch 2; b – P. aff. atavus, Ch/G-175, left M1, Gritsev; c – P. auritus, ZMMU S-174773, right M1, recent; d – P. schoepfelii, NMA P62/0114, right M2, Petersbuch 62; e – Corynorhinus townsendii, ZMMU S-105677, right M1, recent; f – Barbastella maxima, Ch/G-001, right M1, Gritsev.

Text-fig. 6. Lower jaw fragments of different fossil and recent Plecotini, occlusal view. a, b –Plecotus aff. atavus, fragment of left mnd with p4, Gritsev: a – specimen Ch/G-096; b – specimen Ch/G-104; c – P. cf. atavus, SNSB-BSPG 1962 XIX 4201, right p4, Erkertshofen 1, occlusal view; d – P. auritus, ZMMU S-174773, fragment of right mnd with p4, recent; e – P. schoepfelii, NMA P28/0478, fragment of right mnd with p4, Petersbuch 28.