Plesiosminthus cf. margaritae, Freudenthal & Martín-Suárez, 2017

Freudenthal, Matthijs & Martín-Suárez, Elvira, 2017, A revision of European Plesiosminthus (Rodentia, Dipodidae), and new material from the upper Oligocene of Teruel (Spain), Palaeontologia Electronica 9 (1), pp. 1-25 : 9-10

Plesiosminthus cf. margaritae n. sp.

Locality. Vivel del Río 1, MP28, Spain.

Material. Collection Naturalis-Leiden: 40 m 1, RGM

558308–558347; 31 m 2, RGM 558348–558378; 38

m3, RGM 558379–558416; 7 P4, RGM 558525–

558531; 40 M1, RGM 558417–558456; 47 M2,

RGM 558457–558503; 21 M3, RGM 558504–

558524. Collection Zaragoza: 10 m 1, VIV 514–

523; 23 m 2, VIV 524–546; 3 m 3, VIV 547–549; 31

M1, VIV 550–580; 29 M2, VIV 581–609; 10 M3,

VIV 610–619.

Measurements. Appendix 1, Figure 5 .

Description. Number of specimens in brackets.

m1—anteroconid absent (3), small (33), or with cingulum (7); anterolophulid absent (42) or present (2); metalophulid absent; protoconid hind arm absent (1), transverse and low connected to the metaconid (8), transverse and high connected to the metaconid (20), bent and low connected to the metaconid (6), or bent and high connected to the metaconid (9); ectolophid longitudinal (3) or oblique (46); ectolophid complete (32) or anteriorly interrupted (17); mesoconid absent (12), weak (25), or strong (11); mesosinusid open (44) or closed (5); mesolophid reaching the border of the molar (37) or ending in a mesostylid (13), ectomesolophid absent; hypolophulid anterior oblique (1), anterior transverse (41), or transverse (7), hypoconid hind arm absent (45) or short (1); posterolophid continuous (36) or low connected (4); labial posterolophid absent (27), small (7), or strong (14); in five specimens there is a longitudinal connection metaconid-mesoconid; seven specimens have hypoconulid.

m2—labial anterolophid present; metalophulid anterior interrupted (2), anterior complete (40), or connected to the anteroconid (10); protoconid hind arm absent (27), short free (8), transverse and low connected to the metaconid (14), transverse and high connected to the metaconid (1), or bent and low connected to the metaconid (1); ectolophid longitudinal (20), oblique (29), or curved (3); ectolophid complete (51) or anteriorly interrupted (1); mesoconid absent (41), weak (8), or strong (1); mesosinusid open (46) or closed (6); mesolophid long (2), reaching the border of the molar (46), or ending in a mesostylid (4); ectomesolophid absent (51) or weak (1); hypolophulid anterior oblique (1) or anterior transverse (51); hypoconid hind arm absent; posterolophid continuous; labial posterolophid absent (42), small (5), or strong (4); in five specimens there is a longitudinal connection metaconid-mesoconid; one specimen has a hypoconulid.

m3 — lingual anterolophid absent (1), short (2), or long (37); labial anterolophid long; metalophulid absent (1), anterior interrupted (3), connected to the anteroconid (3) or to anterolophulid (32); protoconid hind arm absent (37) or transverse and low connected to the metaconid (2); sinusid open; sinusid narrow backwards (3) or broad backwards (36); mesosinusid open (4) or closed (34); mesolophid of medium length (12), long (21), or reaching the bor- der of the molar (6); ectomesolophid absent; entoconid absent (10), small (17), or large (8); hypolophulid anterior oblique (1), anterior transverse (33), or transverse (1); hypoconid hind arm absent; posterosinusid open (2), half closed (2), or closed (33); shape short triangle (10), long triangle (17), or trapezoid (12); in two specimens there is a longitudinal connection hypolophulid-mesoconid.

M1 — anterocone absent (59) or present (9); anterostyle absent; anterolophule continuous; antecingulum absent (40) or present (29); protolophule transverse (1), double (1), posterior interrupted (1), or posterior (68); sinus open (68), closed (1), or there is an entostyle (1); sinus forward (70) or transverse (1); mesosinus open (70) or closed (1); mesoloph of medium length (1), reaching the border of the molar (61), or connected to a mesostyle (9); entomesoloph absent (70) or short (1); metalophule anterior (31), transverse (39), or curved backward (1); posterosinus large and open (67) or large and closed (1).

M2 — lingual anteroloph absent (21), weak (41), or strong (9); protolophule anterior (27), anterior plus incomplete posterior connection (3), transverse (12), or double (27); sinus open (71) or there is an entostyle (2); sinus strong forward (9) or forward (64); mesosinus open (67) or closed (6); mesoloph reaching the border of the molar (71) or connected to a mesostyle (3); entoloph-protocone connection high (2), low (32), or interrupted (34); metalophule anterior (35) or transverse (36); posterosinus large and open (59) or large and closed (11).

M3 — lingual anteroloph absent (20), weak (3), or strong (2); protocone a distinct cusp (18) or a mere crest (8); protolophule to anterocone (11), to anterolophule (18), or transverse to axioloph (1); sinus absent (2), very small (2), small (15), or deep (10); neo-entoloph absent (3), interrupted (9), low (6), or high (8); mesosinus open (23) or closed (6); mesoloph reaching the border of the molar (26) or connected to a mesostyle (4); old entoloph absent (12), curved spur (1), long spur (1), or complete (16); axioloph absent (2), short posterior spur (2), long posterior spur (8), complete (1), or = old entoloph (17); centroloph absent; centrocone absent (29) or on old entoloph (1); metacone absent (17) or present (12); posterosinus open (8) or closed (21).

N.B. Hugueney et al. (1987) mentioned P. promyarion from VIV1, but did not describe it. We provisionally call it P. cf. margaritae n. sp. in order to avoid creating yet another species, but there are important differences with the type material:

whereas the MV value of m2 is higher in VIV1

(0.610 vs. 0.270), the value for M2 is lower (0.410

vs. 0.535) than in P. margaritae n. sp. from the type locality. Other differences are: The pcdha of m3 is nearly always absent in VIV1; the sinusid of m3 is wider in VIV1; the antecingulum of M1 is more frequent in VIV1; the neo-entoloph of M3 is less developed in VIV1.

Figures

FIGURE 5. Scatter diagrams of molar length (L) and width (W) of Plesiosminthus cf. margaritae n. sp. from Vivel del Río 1 (in mm). 1, m1; 2, m2; 3, m3; 4, M1; 5, M2; and 6, M3.