Martes vetus Kretzoi, 1942

Martes vetus Kretzoi, 1942

Figures 2–7 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 ; Tables 1–3

Material. Deutsch Altenburg 2C: a viscerocranium with a small part of the left neurocranium and preserved left I1, I3, C1, P2–P4, and right I1–M1; right P4; three M1 (2 left, 1 right); a left mandible without most of the ramus and present i3–m2; a right mandible without the ramus, with c1, p2–m3, and m1 (DA/2275/14/77); a right complete mandible with i3–c1 and p2–m2; a right c1; two trigonids, of the left and right m1. Deutsch Altenburg 4B: a left mandible with missing symphyseal part and with p2 and p4; a right mandibular body fragment with m1.

Emended diagnosis. Marten of about the size of Martes martes and M. foina ; cranium with a short and broad viscerocranium; broad incisor row moderately extended forward; moderately convex frontal profile with gently marked concavity in the middle part; compressed, short, and broad temporal region with a broad and short postorbital bar situated almost exactly in the middle of the temporal region; large, inflated, and strongly convex tympanic bullae; short and broad palate, especially in its distal part; V-shaped and convex median indentation of palate; C1 with broad and short crown; large and oval P1; narrow P2; narrow P3 with weakly marked convex margin; P4 with short and low protocone, whose length is smaller than the distal breadth of P4; M1 with trigon length slightly greater than the talon length, highly complicated microrelief on the occlusal surface and moderately large metacone; mandible with a long and slim body, gently convex mandibular lower margin under m1 and vertical edges of the ramus; triangular and shallow masseteric fossa; moderately spaced mental foramens; large p1; m1 with a short trigonid and small metaconid; oval m2; postcranial bones morphologically resembling those of M. martes .

Description. The viscerocranium is short and wide, with a well-marked broadening at the level of canines and P4. The frontal profile in lateral view is moderately convex, with a well-marked concavity in the middle of the frontal part. The frontal line runs somewhat mesially to the nasal bones and depresses slightly on the boundary between the cerebral and facial areas. The muzzle area is broadened at the canines, narrowed behind them, and then gradually widened ( Table 1). The rostral area is proportionally short and massive. The nasal aperture is large and rounded, and the nasal bones are broad, short, and W-shaped. The oval and large orbits have minute lacrimal processes. The infraorbital foramina are large and oval. The upper tooth row is curved distally. The teeth are loosely arranged with short diastemas between I3 and C1, P1 and P2, and P2 and P3; the longest one is between I3 and C1. The broad and curved incisor row is moderately extended forward ( Figure 2 View FIGURE 2 ).

The simple build I1 is relatively short mesio-distally and moderately developed bucco-lingually. The crown is asymmetric, and its main axis runs obliquely from the upper-lingual to the lower-buccal side. The apex of the crown is oriented mesio-buccally and forms an asymmetric triangle. The mesial edge is larger than the distal one. The mesial valley between them is V-shaped, shallow, and both edges are connected to each other. The I2 has a massive and compact crown with a tip directed distally and slightly buccally. The buccal part of the crown is concave and separated from the convex lingual side by a thin and V-shaped cingulum, almost evenly developed mesially and distally. The large, canine-like I3 has a crown placed at an angle of 40 o to the root axis. The crown, ovoid or oval in cross-section, is also flattened on both sides, especially on the lingual side. The top of the crown is twisted disto-lingually. Two edges extend from it, mesial and distal, which at the base of the crown connect with the moderately developed lingual cingulum, forming a thin ridge around the crown. The C1 are flattened laterally and relatively short mesio-distally; weak mesial and distal crests run from their apex to the base. The oval-shaped P1 is a small, monocuspid, single-rooted tooth. Its buccal and lingual margins are convex, and the lingual one is developed more strongly.

The P2 is an elongated tooth, with a stronger distal cingulum. The buccal margin is straight, and the lingual margin is slightly convex in its middle part. The mesial and distal margins are blunt. The protoconid is situated more mesially. Two thin edges run from the apex of the protoconid, the mesial one in a mesio-lingual direction. The distal edge ends exactly medially and is connected with the distal cingulum. The P3 is elongated and narrow. The crown bears an elongated distal cingular projection. The small mesio-buccal prominence of the cingulum forms a faint mesial crest to the apex of the protoconid. This main cusp is located medially and slightly mesially. The two edges running from the apex of the protoconid are thick and sharp. The distal one is not connected with the distal cingulum, and its end forms a small, swellinglike bulge. The cingulum is weakly developed on the lingual side. The mesial and distal margins are blunt or rounded, while the buccal margin bears a moderately developed, median concavity. There is a moderate convexity at the same level, but on the lingual margin.

The long and narrow P4 has straight buccal and lingual margins of the talon. The mesial and

Measurements 9 10 13 14 15 21 27 28 34

Value (mm) 33.36 20.16 8.24 14.94 23.94 21.94 10.62 8.62 19.94

MARCISZAK & NAGEL: FOSSIL MARTENS FROM AUSTRIA distal margins are blunt or rounded. The moderately high paracone bears a thin crest across the mesial border from the apex to the base of the crown. It is separated from the moderately long and low protocone, whose mesial margin is aligned with that of the paracone. Its length is, on average, smaller than the distal breadth of the crown ( Table 2). The metacone is separated from the paracone by a deep valley. The cingulum is more strongly developed on the lingual margin of the metacone. The M1 is large, its breadth is smaller than the length of P4 ( Table 2). The trigon is moderately wide and short, with a moderate and abrupt concavity of the buccal margin. The paracone and the metacone are elongated and well developed; the paracone is larger. They are well separated by a deep, narrow, V-shaped valley. Apexes of both main cusps are connected by a thin, long crest. The talon is shorter than the trigon and they are separated by a deep and broad depression running through the middle part of the crown. The protocone is low and long. It is divided by a shallow and wide valley into two parts of similar length and height. The reduced metaconule is not connected with any other cusp or crest, and is a low, elongated cuspid situated in the middle part of the crown. A long and thin crest corresponding to the buccal margin of the cingulum runs in parallel along the whole talon length. The well-developed lingual cingulum forms a thick crest.

The mandibular body is long and moderately high ( Figure 3 View FIGURE 3 ). Its height measured behind the m1 is comparable to the m1 length ( Table 3). Two rounded mental foramens are moderately spaced and similar in size. The mesial one is situated under the p2, while the distal mental foramen is located under the distal root of p3, slightly lower than the mesial one ( Figure 3 View FIGURE 3 ). The masseteric fossa is moderately deep and its rounded, mesial edge reaches the m1 and m2 boundary. The mesial part narrows dorso-ventrally and its ventral margin only slightly exceeds the midline of the mandibular body in dorso-ventral direction. The lover mandibular body margin forms a gently curved arch, uniformly domed mesially and distally, with the strongest curvature under m1. The symphysial part is moderately massive and elongated. The row of cheek teeth is almost straight and only the distal parts of the p2–p3 crowns moderately arch lingually. In the tooth row, the premolars are located more buccaly in relation to the molars. As a result, the lingual margin of the p4 is displaced more buccally relative to the lingual border of the m1 ( Figure 3 View FIGURE 3 ).

The premolars are loosely arranged with diastemas between c1 and p1, p2 and p3, and p3 and p4. All teeth are situated at a similar level. The triangular crown of the i3 is double cusped, with the main protoconid occupying a larger surface. It is slightly asymmetrical, being more developed on the lingual side. Its vertical top is massive and rather blunt. The distoconid, located laterally to it on the buccal side, has the top of the crown directed slightly disto-buccally. It is a well-developed cuspid, although its shape and size are subject to considerable variability. It is separated from the protoconid by a thin and deep medial notch running almost to the base of the crown, which, in fact, divides the crown into two parts. The c1 is long and robust, with a proportionally short and hook-shaped crown ( Figure 3 View FIGURE 3 ; Table 3).

Two longitudinal grooves run on the buccal and lingual sides of the c1 crown. The relatively large and weakly reduced p1 is an oval, small, and one-rooted tooth. It is tightly squeezed between c1 and p2. Contrary to other premolars, the axis of its crown runs in an arrangement from mesio-lingual to bucco-distal. The two-rooted p2 is low-crowned, with the protoconid strongly displaced mesially. Its occlusal outline is almost rectangular, with an elongated distal part. Two thin crests run in the mesial and distal direction from the top of the protoconid. The distal cingulum forms a thin ridge, collaring the smooth area in the distal part. The mesial part of the crown is longer than the distal one. It bears an elongated distal cingular projection. The mesial and distal margins are blunt, while the buccal and lingual margins are almost straight. The larger p3 has a similar outline in occlusal view, with straight buccal and lingual margins. The mesial and distal margins are blunt. The protoconid is also displaced mesio-medially, although to a lesser degree than in p2. The distal part of p3 is shorter than the mesial one. An elongated distal, cingular projection is oriented slightly disto-buccally. Two thin edges run from the apex of the protoconid. On the distal edge, a small tubercular convexity is present just behind the top. The mesial and distal cingulum are relatively strongly developed. The two-rooted p4 is relatively high-crowned and has the protoconid placed almost exactly centrally and pushed slightly mesially. A relatively large hypoconid is present behind the protoconid. It is associated with the distal crest, running distally from the apex of the protoconid. The mesial ridge is thinner than the distal one. The mesial and distal halves of the tooth are equal in length. The mesial part is narrower than the distal one. The crown is slightly broadened distally. There is a gentle lingual convexity in the middle part of the crown. The lingual margin is straight. The mesial margin is blunt, while the distal one is rounded. The mesial and distal cingulum are relatively strongly developed. The distal, cingular projection is less elongated compared to the rest of the crown. Collared by a thick cingulum, the inner surface of this projection is crescent-shaped and shallow.

The elongated and large m1 has a proportionally short and massive trigonid with a low paraconid and high protoconid. The long and low talonid is similar in breath to the trigonid. The mediumsized, but well-recognized metaconid is connected with the protoconid. A thin, longitudinal ridge surrounds the talonid field, ends on the metaconid base, and runs from the elongated and low hypoconid. The edge of the paraconid is weakly developed. The mesial margin is rounded, while the distal one is blunt. The buccal margin is almost straight, with a gentle concavity at the transition between the trigonid and talonid. The lingual margin of the paraconid and half of the protoconid is straight, while there is a moderate convexity more distally. The cingulum is moderately developed. The m2 is a moderately reduced, one-rooted tooth. The crown has a slightly irregular, rounded occlusal outline, with a length slightly exceeding the breadth. On the trigonid are located the large and low paraconid and protoconid. The larger paraconid is located mesio-buccaly, while the smaller, but not lower protoconid is situated medially and lingually. The talonid is narrower, with a conical and low hypoconid. The moderately developed cingulum is stronger only on the distal margin.

Comparison. Being the same metrically, the DA2 marten morphologically differs more from Martes martes than from M. foina . The viscerocranium is short and broad as in M. foina , with a broad and less extended forward incisor row. In lateral view, the frontal profile is weakly convex, with a slightly marked crossing between the maxillae and frontal region ( Figure 4 View FIGURE 4 ). In M. martes , the rostrum is proportionally longer and narrower, with a similarly less marked widening of the facial part at the level of canines.

No particular differences were found in the morphology of the upper incisors and canines. The C1 of all three marten species are comparable dimensionally, where males are larger than females. On average, the C1 of Martes vetus is slightly more robust, but the ranges of variation strongly overlap. Morphologically, the C1 of M. vetus is characterised by a more curved, shorter and wider crown, which resembles more the C1 of M. foina than the more elongated and narrower C1 of M. martes . The right P1 of the DA2C marten measured 2.74 mm, which falls well into the range of variability of M. vetus (2.69 mm, 2.46–2.94 mm, n = 13) and M. martes (2.59 mm, 2.29–3.21 mm, n = 129), but distinctly exceed values obtained for M. foina (1.97 mm, 1.78–2.49 mm, n = 114). The P1 of M. vetus is not only larger, but also more robust, and the B/L index for this species is 68.5 (62.4– 72.8, n = 13) compared to 69.7 in the DA2 marten. The P1 of M. martes is even more massive (71.9, 66.4–77.8, n = 129), while that of M. foina is notably narrower and more reduced (55.6, 52.9–64.3, n = 114). The P3 of M. vetus is similar to that of M. foina in having a narrow crown, with a weaklymarked convex margin ( Figure 4 View FIGURE 4 ). The P3 B/L mean ratio for M. vetus (48.7) is similar to that of M. foina (47.7). Morphotype A1, which is characteristic for M. foina (97%), without the lingual bulge, occurs also in the DA2 marten. This morphotype rarely occurs in M. martes (19%), for which the morphotype A2 is the most typical, with a small to moderate lingual bulge (73%). This species possesses much broader P3 (B/L = 62.4), which is consistent with the strongly developed lingual convexity.

The P4 of the DA2 marten is moderately long and low, and it is slightly shorter than the distal breadth of the crown ( Figure 4 View FIGURE 4 ). The protocone length to the distal breadth (L pr/Bp) index in the DA 2 specimens (97.1, 96.2–98.6, n = 3) corresponds well with the data obtained for Martes vetus (94.5). Martes foina has distinctly shorter protocone (80.8), while its length in M. martes exceeds the distal breadth of P4 (L pr/Bp = 105.7). The P4 of the DA2 marten represents morphotype A2, with a notch between the protocone and parastyle, nonprotruding protocone, and a concave buccal outline. This morphotype often occurs in M. foina (33%) and M. martes (24%). The P4 from the Sackdilling holotype belong to morphotype A1, with a notch between the protocone and parastyle, the protocone being shifted mesialy to the parastyle, and a concave buccal outline ( Marciszak et al., 2021). This is also the most common morphotype in extant martens (58% in both). Other morphotypes are much rarer (Gimranov and Kosintsev, 2015).

The M1 of the DA2 marten has a relatively wide trigon, visibly broader than that in the Sackdilling holotype. The index of the trigon length to the M1 breadth (L ta/L tr) in DA2 is higher (78.7, 75.9– 81.4, n = 4) than that obtained for the Sackdilling marten (69.0, 65.5–72.5, n = 2) ( Marciszak et al. 2021). Data from both localities coincide with values of this index for Martes vetus (66.8, 59.2–76.1, n = 58). In this matter, M. vetus shows intermediate values between M. foina (62.6, 58.0–67.5, n = 114) and M. martes (75.4, 68.3–85.3, n = 129). The outline is irregular, and the occlusal surface is more complicated than in most specimens of M. foina and M. martes . The single M1 of the DA2 marten was assigned to morphotype A2, with straight lingual and rounded buccal outline and the preprotocrista bearing two small cusps. This morphotype (55%), together with A1 (32%), is the most common for M. martes , while others occur only rarely (Gimranov and Kosintsev, 2015). In M. foina , only group B morphotypes occur, with a deep groove between the paracone and metacone (Gimranov and Kosintsev, 2015). This is a reliable specific feature for M. foina , which was already pointed out by Wolsan et al. (1985) and Wolsan (1988, 1989a). The sole M1 from Sackdilling represents morphotype D2, with a straight lingual and rounded buccal outline, where the preprotocrista possesses two small cuspids and the hypocone and metaconule are present.

Previous authors, e.g., Heller (1930, 1933, 1936), Brunner (1933), or Dehm (1962), who described and studied remains of Martes vetus , practically did not deal with the mandible morphology. Only Anderson (1970) noted that the mandibular body is relatively shallow, the masseteric fossa reaches its maximum at the m1/m2 border, and the mental foramens are situated relatively far apart. She noted that the distance between them in M. vetus is 4.96 mm (3.70–6.10 mm, n = 13), while the mental foramens spacing ranged between 3.70– 7.40 mm in M. martes and 2.00– 3.40 mm in M. foina . A detailed revision showed that this feature is the most useful for taxonomic classification of European martens. The obtained results are close to the data presented by Anderson (1970), where the spacing of the mental foramens in the DA2 marten is 4.98 mm (4.02–5.74 mm, n = 5), and well corroborates with that of M. vetus (4.77 mm, 3.78– 5.94 mm, n = 28). This measurement shows intermediate values between that of M. foina (2.53 mm, 1.97–3.41 mm, n = 114) and M. martes (6.13 mm, 5.36–7.97 mm, n = 129) ( Figure 5 View FIGURE 5 ).

Considering other features as well, the mandible of Mares vetus is morphologically more similar to that of M. martes in having an elongated and moderately high mandibular body, the condyloid processes located slightly below or at the level of p4/m1, and a similar shape of the mandibular ramus. In M. vetus and M. martes , the mesial and distal edges of the coronoid process are approximately of the same length and form a not fully isosceles triangle. In M. foina , the mesial edge of this process is more inclined than the distal one, which is almost vertical and therefore considerably shorter. That is why, in relation to the mandibular body, the ramus is proportionally shorter and more vertical.

The morphology of the angular process is more variable; however, there are some differences ( Figure 6 View FIGURE 6 ). The morphology of the angular process in the DA2 marten strongly resembles that in Martes vetus and M. martes , which is longer and hooked, contrary to the short and straight angular process of M. foina . There are also some differences in the shape of the masseteric fossa, which, on average, is shallower with a more triangular mesial edge in M. vetus and M. martes . In M. foina , this structure is usually slightly deeper, with a more rounded mesial edge. However, the shape of the masseteric fossa is also highly variable. It is rather more related to age and sex (in males and older individuals the masseteric fossa is deeper), than to species-specific characteristics. Therefore, the diagnostic values of this feature is limited and cannot be taken into consideration during species discrimination. The mandible of M. vetus resembles that of M. foina and differs from that of M. martes simultaneously in having a strongly curved mandibular body, with a notably marked curvature of the lower margin under m1. In contrast, the mandibular body of M. martes is straighter, with a lower margin having no or only a gentle curvature. The variability of all the above features is relatively smaller than in most teeth, but still relevant and therefore diagnostic value of those characters should be considered with caution.

There are also some differences between the studied martens in the morphology of the lower dentition. Our studies confirmed all previously known differences and revealed a few others. The great size variability of the c1 of Martes vetus was already highlighted by Heller (1933). When comparing size values of different marten species, differences seemingly result from sexual dimorphism. The c1 of M. vetus is on average slightly narrower than c1 of M. martes and M. foina . However, the ranges of variation are almost the same, and c1 of all three martens also do not differ morphologically. The p1 of M. vetus tends to be larger and less reduced (2.67 mm, 2.32–3.14 mm, n = 33) than in M. foina (2.21 mm, 1.79–2.56 mm, n = 114), and shows great similarity to p1 of M. martes (2.54 mm, 2.14–3.19 mm, n = 129).

The p1 of Martes vetus is not only larger, but also more robust, with a B/L index of 73.8 (66.2– 80.2, n = 33), while this ratio is 72.9 (64.9–84.6, n = 129) in M. martes and 54.1 (53.2–63.9, n = 114) in M. foina . The p1 of the DA2 marten is relatively small (L = 2.27 mm), but rather wide (B/L = 67.8), and the robustness index falls into the range of variability of M. vetus . Metrically, the p2, p3, and p4 of all three martens are similar, only M. foina tends to show slightly higher values. Morphologically, those lower premolars showed some tendency to variability, although its range is not so wide. The p2 and p4 of M. vetus are narrower than that of M. martes and M. foina . In M. vetus , the B/L index of p2 is 50.7 (46.8–56.8, n = 29) and 45.2 (41.6–48.6, n = 38) in p4. Values of this ratio are 54.8 (48.9– 61.1) for p2 and 53.2 (48.2–57.6) for p 4 in M. martes (n = 129). In M. foina (n = 114), it is 54.9 (48.7– 64.3) for p2 and 54.5 (48.8–61.6) for p4. The robustness index of p3 is almost the same for all three martens. Of the three p3 from DA2, two were assigned to morphotype A2, where a small distal additional cuspid is present on the distal ridge of the protoconid. The third p3 represents morphotype A1, where this cuspid is absent, and which is the dominant morphotype in M. foina (97%) and M. zibellina (82%) (Gimranov and Kosintsev, 2015). In M. martes , the most numerous is morphotype A2 (73%), but A1 also occurs relatively often (17%). Two p4 from DA2 were assigned to morphotype A3, where a small distal additional cuspid is present on the distal ridge of the protoconid, at lower level. This morphotype occurs in all three extant martens, but in low proportion: M. foina (3%), M. zibellina (9%), and M. martes (10%). Much more numerous in those species are morphotypes A1 (58% in M. foina and M. martes , and 40% in M. zibellina ), without the additional cuspid, and A2 (33% in M. foina , 24% in M. martes and M. zibellina ), where this cuspid is located high in relation to the protoconid (Gimranov and Kosintsev, 2015).

In the morphology of the lower dentition, most authors focused on m1. Dehm (1962) and Anderson (1970) highlighted the larger value of the mean size of m1. Additionally, Anderson (1970) and Wiszniowska (1989) mentioned that the m1 of Martes vetus has a proportionally short trigonid as in M. martes , and a small metaconid as in M. foina . Rabeder (1976) noted the lack of the so-called “paraconid edge”, a strong, median concavity situated between the disto-lingual margin of the paraconid and the mesio-lingual margin of the metaconid. When dealing with the DA2 material, it shows to be small marten, dimensionally smaller from other populations and species. The mean of L m 1 in DA2 is 8.38 mm (7.97–8.78 mm, n = 5), which is clearly smaller than in extant martens, where L m 1 in M. martes is 10.71 mm (10.08– 11.38 mm, n = 63) in males and 9.64 mm (9.16– 10.27 mm, n = 75) in females. Similarly, in M. foina , L m1 has higher values in males (L m1 = 10.64 mm, 10.04–11.34 mm, n = 68) compared to females (9.35 mm, 8.76–9.88 mm, n = 44). When comparing the DA2 material with two relatively numerous populations from Schernfeld and Żabia Cave, differences seemingly result from sexual dimorphism. In Schernfeld, M. vetus is larger (L m1 = 10.76 mm, 10.17–11.89 mm, n = 23 in males, and 9.44 mm, 8.74–9.89 mm, n = 17 in females) than in the Żabia Cave (L m1 = 9.87 mm, 9.57– 10.52 mm, n = 7 in males, and 8.78 mm, 7.98–9.47 mm, n = 15 in females). The DA2 marten is relatively small, but its dimensions fall into the range of size variability of M. vetus females, and indicates a predominance of females at this locality. Only a single, incomplete m1 documents the presence of a larger male.

The general morphology of m 1 in Martes vetus is typical for the genus Martes , with a proportionally broad and trenchant talonid, comparable in width with the trigonid. This is well illustrated by the talonid (B ta) to trigonid breadth (B tr) index. The mean value of this ratio is 98.9 (94.1–103.1, n = 83) in M. vetus , 106.1 (103.1–116.9, n = 139) in M. martes , and 93.4 (87.5–103.1, n = 114) in M. foina . It has been also found that M. vetus has not only a moderately narrow talonid, but also a relatively short trigonid. The mean ratio of the talonid (L ta) to trigonid length (L tr) is 46.9 (36.2–58.1, n = 86) in M. vetus , while 56.8 (41.5–72.3, n = 139) in M. martes and 37.6 (26.7–47.5, n = 114) in M. foina . In both indexes (L ta/L tr and B ta/B tr), the m1 of M. vetus shows intermediate values between M. martes and M. foina . The same was obtained for the material from DA2, where the mean of L ta/L tr is 52.6 (49.2–55.4, n = 4) and the mean of B ta/B tr is 98.8 (98.1–99.7, n = 5). Two m1 of DA2 were assigned to morphotype A1, were the distinct and robust hypoconid, as a sole cusp, occupies approximately half of the talonid basin. Two other m1 represents morphotype A2, where the small, but well-recognizable hypoconulid is adjacent to the robust hypoconid. Finally, the last tooth belongs to morphotype B2, where the hypoconulid is adjacent to the relatively small-sized hypoconid. The frequency of occurrence of particular morphotypes in extant martens is highly variable. There is, however, a noticeable difference between M. foina , in which group A morphotypes predominate (55% A1, 40% A2), M. martes , for which group B morphotypes are typical (24% B1, 67% B2), and M. zibellina , in which morphotypes B2 (44%) and C2 (45%) are the most common (Gimranov and Kosintsev, 2015). Other morphotypes occur only rarely.

In this aspect, the DA2 marten resembles the most Martes foina , because group A morphotypes also predominate. But the limited number of specimens should also be taken into account, especially considering that other morphotypes in the much more numerous populations of Schernfeld and Żabia Cave occurred also relatively often. Anderson (1970) noted some differences in the morphology of m2, being long and narrow in M. vetus , slightly broader than longer in M. martes , and nearly round in M. foina . Both preserved m2 from DA2 were assigned to morphotype A2, where the closely spaced protoconid and metaconid form a crest. This is also the dominant morphotype in M. foina (83%) and M. zibellina (96%), but occurs rarely (9%) in M. martes . For this species, morphotype A1 is typical (91%), where the protoconid and metaconid are separated from each other (Gimranov and Kosintsev, 2015). When comparing the B/L index of m2, both teeth from DA2 (89.2, 87.9– 90.5, n = 2) corroborate well with the data obtained for M. vetus (92.7, 84.5–99.5, n = 46). The m2 of this marten tends to be narrower than in extant martens, in which the mean B/L ratio is higher, approximately 107.4 (94.5–112.4, n = 138) in M. martes and 99.7 (91.6–102.5, n = 112) in M. foina (83%).

In sum, the analyzed marten material from the DA2 locality both metrically and morphologically corroborates well with the respective dentognathic material of Martes vetus , which allows assigning it to this species. The comparison with two extant martens, M. martes and M. foina , showed a similar number of differences and similarities between these three species. Moreover, many of those features and indexes of M. vetus showed intermediate values between M. martes and M. foina . A concluded list of differences and similarities between those three martens is given below.

Comparison with Martes martes . Individuals of M. vetus from DA2 differ from M. martes in: (1) shorter and broader viscerocranium; (2) broader and less extended forward row of incisors; (3) strongly convex frontal profile in lateral view, with well-marked concavity in the middle part; (4) shorter, wider, and more strongly curved crown of C1; (5) narrower P2; (6) narrower P3 with weakly marked convex margin; (7) shorter and lower protocone and stronger lingual cingulum of P4; (8) less expanded trigon of M1 with more complicated microrelief on the chewing surface and less reduced metacone; (9) narrower spacing of mental foramens on the mandibular body; (10) slightly narrower c1; (11) narrower p2; (12) narrower p4 with an additional cuspid located low in relation to the protoconid; and (13) narrower m2 with closely spaced protoconid and metaconid that form a crest ( Figure 7 View FIGURE 7 ).

Individuals of Martes vetus from DA2 resemble M. martes in: (1) larger, less reduced, and robust P1; (2) elongated and moderately high mandibular body; (3) condyloid processes located slightly below or at the level of p4/m1; (4) shape of the mandibular ramus, where the mesial and distal edges of the coronoid process are approximately of the same length and form a not fully isosceles triangle; (5) longer and hooked angular process; (6) larger, less reduced, and robust p1; and (7) m1 with short trigonid ( Figure 7 View FIGURE 7 ).

Comparison with Martes foina . Individuals of M. vetus from DA2 differ from M. foina in: (1) less massive crown of C1; (2) smaller, narrower, and less reduced P1; (3) M1 with more complicated microrelief on the chewing surface and less reduced metacone; (4) wider spacing of mental foramens on the mandibular body; (5) elongated and moderately high mandibular body; (6) condyloid processes located slightly below or at the level of p4/m1; (7) shape of the mandibular ramus, where the mesial and distal edges of the coronoid process are approximately of the same length and form a not fully isosceles triangle (in M. foina , the mesial edge is more inclined than the distal one, which is almost vertical and thus considerably shorter); (8) longer and hooked angular process (short and straight in M. foina ); (9) slightly narrower c1; (10) larger, less reduced, and broader p1; (11) narrower p2; (12) narrower p4 with an additional cuspid located usually low in relation to the protoconid; (13) shorter trigonid of m1; and (14) narrower m2 ( Figure 7 View FIGURE 7 ).

Individuals of Martes vetus from DA2 resemble M. foina in: (1) shorter and broader viscerocranium; (2) broader and less extended forward row of incisors; (3) strongly convex frontal profile in lateral view, with well-marked concavity in the middle part; (4) shorter and broader crown of C1; (5) narrow P2; (6) narrow P3 with weakly marked convex margin; (7) P4 with short and low protocone, which length is smaller than the distal breadth; (8) M1 with less expanded trigon and irregular occlusal outline; (9) strongly curved mandibular body, with notably marked curvature of the lower margin under m1; (10) m1 with a small metaconid and a talonid slightly narrower than the trigonid; and (11) morphology of m2, where the closely spaced protoconid and metaconid are connected by a distinct crest ( Figure 7 View FIGURE 7 ).

Possible occurrence of Martes zibellina at DA2. Rabeder (1976) described a right mandible body with the ramus fr. and present c1, p2–p3, and m1 (collection no. UWPI 2275/14/77) from DA2 as Martes cf. zibellina . He classified this specimen to this species according to its small size, lower crowns of c1, p2, and p3, and the small metaconid and broad talonid of m1. Among other features of this individual, he also noted the low mandibular body, the two mental foramens being located under p2 and p3, the moderately elongated and curved c1, the p1 alveolus directed distally, the low m1 without median concavity situated between the disto-lingual margin of the paraconid and the mesio-lingual margin of the metaconid, the trigonid slightly narrower than the talonid, the low hypoconid located on the trenchant talonid, and the minute hypoconulid. All these features are also characteristic for the morphology of M. vetus .

Rabeder (1976) did not discuss the differences between mandibles classified as Martes cf. zibellina and those of M. vetus . Only when describing the trigonid of the isolated m1 as M. cf. vetus , he concluded that this tooth cannot be assigned to M. zibellina , which differs in having smaller size and more strongly reduced metaconid of m1. He compared both specimens with the mandible (L m1 = 9.28 mm) from Sackdilling Cave, which was studied before by Brunner (1933), Anderson (1970), and Marciszak et al. (2021). More recently, Jiangzuo et al. (2021) agreed with Rabeder’s (1976) original classification as M. cf. zibellina . However, they also pointed out some differences, such as the relatively wide m1 talonid and the presence of an additional small cuspid in the talonid basin or in the entoconid ridge, which is not present in the analyzed specimen.

Rabeder (1976) also highlighted his doubts about the correctness of the identification of this particular specimen. Considering that Martes zibellina is unknown from the European fossil record and that its extant populations show a remarkable geographic variability, this determination is even less probable. Of course, we cannot fully reject the possible presence of other marten species at DA2, but, based on our current state of knowledge, it is highly unlikely. There are no clear differences between M. zibellina and M. martes in the structure of the skull and teeth. As it was already pointed out above, the morphology of M. vetus showed intermediate values by many features and indexes between M. martes and M. foina , which makes unambiguous classification extremely difficult or even impossible. Additionally, the presence of small specimens, metrically and morphologically indistinguishable from the DA 2 specimen, was also reported from the Schernfeld and Żabia Cave populations. All of them were, after detailed and careful revision, identified as females of M. vetus .