Parvagula palulae Lange-Badré
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publication ID |
https://doi.org/ 10.4202/app.00146.2014 |
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persistent identifier |
https://treatment.plazi.org/id/03F887DC-B228-A009-806C-DC45FAC35A4E |
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treatment provided by |
Felipe |
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scientific name |
Parvagula palulae Lange-Badré |
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Parvagula palulae Lange-Badré in Godinot et al., 1987
Figs. 2–5.
Holotype: UM / PAT 4 , right dentary bearing p2–m1, and alveoli for p1, and m2–3.
Type locality: Palette, Provence, Bouches-du-Rhône, France.
Type horizon: Early Eocene.
Material. —UM/FNR 51, right m1?; UM/FNR 52, left trigonid of m1?; UM/FNR 53, right fragmentary dentary bearing
p4; early Eocene; Fournes, Minervois, Hérault, France; UM/ FDN 153, left trigonid of m1?; early Eocene; Fordones, Corbières, Aude, France.
Emended diagnosis (modified from Godinot et al. 1987).— Small proviverrine characterized by the presence of a deep dentary and symphysis; four two-rooted and closely spaced premolars; p4 with large paraconid and entoconid; molars with short and wide talonid and lingually closed postfossid, large and bulbous entoconid, paraconid poorly developed, and a m3 smaller than m2.
Measurements.—UM/PAT 4: p1, 1.9*×0.8*; p2, 2.3×1.1; p3, 2.4×1.3; p4, 2.5×1.4; m1, 3.0×1.5; m2, 2.7*×1.15*; m3, 2.1*×1.07*; DD, 4.5. Asterisked measurements are based on alveoli. UM/FNR 53: p4, 2.97×1.27; DD, 4.0. UM/FNR 51: m1?, 3.19×2.2.
Description. —The dentary ( Fig. 2) found in Palette (UM/PAT 4, holotype) is deep and displays an important dorso-ventrally elongated symphysis; the latter structure extends below the anterior root of p2. Two mental foramina are present respectively below the p1 and p3. The coronoid crest is clearly vertical. The angular process is dorsally located compared to the body of the dentary; there is a concavity anteriorly to the process. The Computed Tomography (CT) reconstruction of UM/PAT 4 suggests that the mandibular condyle, which is unpreserved on the specimen, is dorsal to the tooth row. Based on the reconstruction, we also identified the mandibular foramina. The morphology of the ascending ramus is reminiscent of that described for Boritia duffaudi from the early Eocene of La Borie (Aude, France) ( Solé et al. 2014a).
The four premolars, which are all two-rooted, are closely located each other along the dentary on UM/PAT 4. The p2, p3 and p4 are symmetric in lateral view. Unfortunately, the premolars are strongly worn ( Fig. 2), as is the sole molar (m1): we can, however, note that the talonid is short and wide and there is a large entoconid ( Fig. 2). The m3 is clearly shorter than the m1 and m2 ( Fig. 2A).
Three specimens have been collected at Fournes: one complete p4, one complete m1, and one trigonid of m1, while only one trigonid of m1 has been found in Fordones.
The p4 (UM/FNR 53) is almost symmetric in lateral view Fig. 3A View Fig 1 View Fig , A 2). The paraconid is clearly individualized. The protoconid is elongated mesio-distally. The talonid is relatively wide. Only two cusps are present on the talonid: the hypoconid and the entoconid. The hypoconid is high and larg- er than the entoconid; the latter is well developed and is lingually located. There is no crest joining the two cusps. There is only a weak postcingulid on the labial side of the tooth.
UM/FNR 51 (m1?) is almost complete: only the apex of the paraconid is broken ( Fig. 3D View Fig 1 –D View Fig 3 View Fig ); UM/FNR 52, however, provides additional information on the paraconid ( Fig. 3C View Fig 1 –C View Fig 3 View Fig ). The trigonid is twice as high as the talonid. The paraconid is short and slightly mesially shifted. Moreover, it is distinctly lower than the metaconid and protoconid. The metaconid is robust, lower than the protoconid and its apex is tilted lingually. The talonid, which is short, displays a wide postfossid and bears distinct cusps. The latter are distally located. The hypoconulid appears slightly higher than the hypoconid and entoconid, but the apex of the hypoconid is broken. The entoconid is cuspate and bulbous. The postfossid is enclosed lingually and the distance between the bases of metaconid and entoconid is short. The cristid obliqua is clearly oblique and climbs on the distal wall of the trigonid towards the protocristid notch. Only a precingulid is visible along the mesiolabial part of the paraconid.
The morphology of the only known specimen from Fordones (UM/FDN 153) ( Fig. 3B View Fig 1 –B View Fig 3 View Fig ) fits with that of UM/ FNR 51 and UM/FNR 52. However, UM/FDN 153 is slightly smaller than the specimens from Fournes. Moreover, as not- ed by Marandat (1991), the lingual opening of the prefossid on UM/FDN 153 is slightly higher located; this is a primitive condition.
The specimens UM/FNR 51 and UM/FNR 52 from Fournes are considered as possible m1 despite the fact that they are larger than the m1 present on UM/PAT 4, we indeed consider that the fossils from Fournes are younger than those from Palette (see below). However, it is worth keeping in mind that the variability is poorly known for the species due to its weak fossil record.
We estimated, after the methodology proposed by Morlo 1999), that Parvagula palulae probably weights close to 60 g at most.
Remarks. —The lower molars described above (UM/FNR 51, UM/FNR 52, UM/FDN 153) have been described by Marandat (1991) as cf. Hyracolestes sp. The small mammal Hyracolestes has been originally described as a primitive creodont by Matthew and Granger (1925). However, it is still a poorly known taxon, based only on very sparse material. Therefore, it has had a confusing taxonomic history. Based on similarities with Sarcodon, Lopatin and Kondrashov (2004) referred this genus to the Sarcodontinae within the micropternodontid soricomorphs, which are insectivorous mammals with well-expressed carnivorous adaptations. Missiaen and Smith 2008) elevated Sarcodontinae to family rank, but rather considered them as members of Cimolesta , with uncertain ordi-
nal affinities based on the presence of only two molars, the absence of hypoconal shelf on P4 and M2, and a different stratigraphic distribution.
Marandat’s (1991) hypothesis was supported by the close morphological resemblance between the French fossils and a fossil (PSS 20-124) from Tsagan Khushu ( Mongolia, Ypresian) referred to cf. Hyracolestes sp. by Russell and Dashzeveg (1986). The similarities between the French and Mongolian specimens are actually striking (see below). However, the similarities with specimens undoubtedly referred to Hyracolestes are less supported. The French and Mongolian specimens differ from Hyracolestes by the absence of transversal alignment of the talonid cusps, the less mesially shift- ed paraconid, the lingual closing of the postfossid, and the presence of a precingulid.
Lange-Badré in Godinot et al. (1987) created a new genus and new species for a dentary found in Palette: Parvagula palulae . Solé (2013) referred this taxon to the Proviverrinae ; these hyaenodonts are endemic to Europe. The three lower molars from Fournes and Fordones are morphologically similar to that of Parvagula palulae ; they share with the molar of UM/PAT 4 the trigonid morphology characterized by a low paraconid, the short talonid, the circular alignment of the talonid cusps, and the presence of a precingulid.
The p4 from Fournes (UM/FNR 53) is also similar both in size and morphology to that of the holotype of Parvagula palulae . The p4 of UM/PAT 4 is, however, more oval in occlusal view than that of FNR 53, and the apex of the protoconid is slightly more mesially located. These features are similar to the p4 of Tinerhodon (late Paleocene of Morocco) (see Gheerbrant et al. 2006: fig. 6a); the differences between the p4 from Palette and Fournes could be due to an older age of the fossil from Palette compared to that from Fournes (see below). The specimen from Fournes, which is less worn than that from Palette, also differs from the latter by the presence of a paraconid and by the presence of an entoconid. The presence of a space between the p3 and p4 on UM/PAT 4 implies that a paraconid was possibly present on p4. Based on personal observations of the p4 talonid of UM/PAT 4, Solé (2013) coded in his matrix the presence of the entoconid. He observed a small but worn crest on the lingual part of the talonid that could result from the presence of an entoconid. Despite a slightly more derived morphology, UM/FNR 53 does not really differ from the p4 present on UM/PAT 4. These features, such as the presence of paraconid and entoconid, are important because the morphology of the p4 is important for distinguishing the Proviverrinae from other subfamilies (see below).
The sole other early proviverrine recorded from the lowermost Eocene is Eoproviverra eisenmanni from Rians ( Godinot 1981; Solé et al. 2014a; Fig. 4 View Fig ). However, the wear of the teeth of UM/PAT 4 prevented detailed comparisons with Eoproviverra ; this comparison is important because the specimens from Rians and Palette are the oldest proviverrine fossils. The specimens from Fordones and Fournes now allow a comparison between the two proviverrine species, although the comparison can be made only on the base of the lower molars.
The lower molars of the two proviverrine taxa display large and well individualized entoconid; this feature clearly distinguishes them from the molars of sinopines from Dormaal and Le Quesnoy ( Prototomus and Galecyon ) ( Fig. 5 View Fig ). The presence of a large entoconid is also a feature of Arfia , which is also recorded in Dormaal, Erquelinnes, and Le Quesnoy ( Smith and Smith 2001; Missiaen et al. 2013; Solé et al. 2013), but the two proviverrines differ from Arfia Arfiinae ) by a narrower talonid, less developed cingulids and smooth enamel.
The molars from Fournes and Fordones are distinguished from those of Eoproviverra by a less mesially shifted paraconid, a shorter paracristid, a lingually closed postfossid, and a shorter but wider talonid and postfossid ( Figs. 3 View Fig , 4 View Fig ). As a result, the molars of Parvagula appear less secant (e.g., less developed paraconid) but more robust (e.g., wider postfossid) than those of Eoproviverra . These differences add to the distinction of the two taxa and their generic distinction thus should be maintained.
The p4 of Eoproviverra is presently unknown: only its upper and lower molars have been found ( Godinot 1981). Consequently, the p4 present on UM/FNR 53 could be that of Eoproviverra . However, the p4 of UM/FNR 53 is slightly larger than the molars of Eoproviverra (from Godinot 1981: MNHN.F.RI400, m2, 2.8×1.7; MNHN.F.RI204, m1, 2.1×0.8; m2, 2.4×1.6; MNHN.F.RI203, m3, 2.5×1.6). Moreover, because Parvagula is already recorded in Fournes, the reference of UM/FNR 53 to Parvagula is the most parsimonious hypothesis.
Finally, it is worth mentioning that the overall robustness of the molars and the close spacing of the premolars recall that of early Eocene genera Morlodon Solé, 2013 and Boritia Solé, Falconnet, and Laurent, 2014 , which are possibly related to durophagous Matthodon . This would indicate that the development of the peculiar durophagy of Matthodon may have developed early in the history of the proviverrines. However, these relationships cannot be definitively established based on the currently available material.
Stratigraphic and geographic range. —Early Eocene; Palette (Provence, Bouches-du-Rhône), Fournes (Minervois, Hérault) and Fordones (Corbières, Aude), France.
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University of Marburg |
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