Stehlinia quercyi ( Revilliod, 1922 ) Sigé, 1975

Harrison, David L. & Hooker, Jeremy J., 2010, Late Middle Eocene bats from the Creechbarrow Limestone Formation, Dorset, southern England with description of a new species of Archaeonycteris (Chiroptera: Archaeonycteridae), Acta Chiropterologica 12 (1), pp. 1-18 : 11-12

Stehlinia quercyi ( Revilliod, 1922) Sigé, 1975

*1922. Paleunycteris quercyi Revilliod 144, fig. 55.

Holotype

Right mandibular ramus with C 1 –M 3, ascending ramus broken. Phosphorites du Quercy, NMB QP. 727.

Material

HZM 4.36362 right C 1. CL 1.34; CW 0.96; CH (labial) 1.86 (base of cingulum to tip); total length with root 3.33 ( Figs. 5 A–D, 9D–F).

Description

HZM 4.36362 is a well preserved lower right canine of a medium small microchiropteran, with the root intact. The crown is relatively short and broad at the base, with the tip curved lingually. The distal surface has a central ridge bordered on each side by shallow grooves; on the lingual surface there is a mesial groove, while the buccal surface is quite smooth and evenly convex.

The lower canine of S. quercyi described here agrees well with the description of this element in Stehlinia minor Revilliod, 1922 provided by Sigé (1974: 260, fig. 2) differing only in being significantly larger and in having a pronounced median ridge, bordered by grooves on its distal surface. A distinctive feature of HZM 4.32362 is the presence of a mesio-lingual cingular cusp, which is lacking in the lower canine of Archaeonycteris ( Fig. 3 ) as well as in the C 1 of modern Rhinolophus and Hipposideros species. It is also absent in the C 1 of Vespertiliavus gracilis Revilliod, 1920 ( Sigé, 1988: fig. 8) The C 1 of P. schlosseri is distinctly shorter (CL 1.06–1.18 but wider CW 1.05–1.13). Sigé (1988: table 4) showing that this is a much more gracile tooth. It also lacks the mesio-lingual cingular cusp.

Discussion

Three species of Stehlinia occur in the European Tertiary. All three are now known to occur in Britain. Stehlinia minor ( Revilliod, 1922) is record- ed from the Late Eocene Bembridge Limestone

Formation, Headon Hill ( Hooker et al., 2004: 163). Stehlinia quercyi is a distinctly more robust species recorded here for the first time in Britain from the Creechbarrow Limestone. Stehlinia gracilis Revilliod, 1919 occurs in the Early Oligocene Hamstead Member, Bouldnor Cliff, Isle of Wight ( Hooker et al., 2004)

Although only represented by a canine, size, the main criterion for distinguishing species of Stehlinia , determines the presence of S. quercyi at Creechbarrow. This species, apart from the essentially unlocalised holotype (Quercy undifferentiated), is recorded from Perrière (Quercy) ( Remy et al., 1987) and Eclépens B, Switzerland ( Hooker and Weidmann, 2000). Both records are from the early Priabonian (early Headonian ELMA). The Creechbarrow record therefore represents a range extension back into the Bartonian.

Figures

FIG. 5. Creechbarrow bats. Stehlinia quercyi HZM 4.36362. Right C1 in A — distal, B — lingual, C — buccal and D — occlusal views. Arrow indicates mesiolingual cusp. Scale = 1 mm. Microchiroptera gen. et sp. indet. HZM 22.34774. Right trigonid of lower molar in E — buccal, F — distal, G — lingual and H — occlusal views. Rhinolophidae gen. et sp. indet. HZM 2.38159. Right

FIG. 3. Archaeonycteris brailloni, Avenay and Mutigny Quarries, N.E of Epernay, Marne, France. MNHN Av 4564. Right M1 (holotype): A — occlusal, B — mesial views MNHN[A8]. Left M in C — lingual and D — distal views MNHN Av 6786. 1/2 Left C1 in E — occlusal, F — lingual and G — buccal views. Drawn from casts of type material. Scale = 1 mm