Scontromeryx apruthiensis ( Mazza et Rustioni, 2011 )

Van Der Geer, Alexandra A. E., 2014, Systematic revision of the family Hoplitomerycidae Leinders, 1984 (Artiodactyla: Cervoidea), with the description of a new genus and four new species, Zootaxa 3847 (1), pp. 1-32: 18-20

publication ID

http://dx.doi.org/10.11646/zootaxa.3847.1.1

publication LSID

lsid:zoobank.org:pub:C7BDD136-2686-4049-B395-684797B26406

persistent identifier

http://treatment.plazi.org/id/03D287A2-FD18-3717-FEF7-F913FD91FE4D

treatment provided by

Plazi

scientific name

Scontromeryx apruthiensis ( Mazza et Rustioni, 2011 )
status

 

Scontromeryx apruthiensis ( Mazza et Rustioni, 2011) 

Hoplitomeryx Leinders, 1984  — Mazza & Rustioni 1996: p. 95 [SCT 16, SCT 29, SCT 50].

Hoplitomeryx  sp. Leinders, 1984 — Mazza & Rustioni 1999: p. 305, fig. 1 [SCT 16, SCT 29, SCT 50, SCT 58, SCT 59, SCT 71, SCT 81, SCT 89, SCT 102, SCT 125, SCT 195].

Taxon B—Mazza & Rustioni 1999: p. 307, fig. 2 [SCT 51, SCT 67, SCT 79].

Hoplitomeryx apruthiensis Mazza & Rustioni, 2011  — Mazza & Rustioni 2011 (partim): p. 1304, 1322, 1330, fig. 4, 5, tables 1, 2 [SCT 16, SCT 29, SCT 50, SCT 51, SCT 58 + SCT 67, SCT 59, SCT 71, SCT 79, SCT 81, SCT 89, SCT 102, SCT 125, SCT 195].

Holotype. Right hemimandible SCT 29 ( Figure 4View FIGURE 4, D, E, F in Mazza & Rustioni 2011).

Paratypes. Maxillaries SCT 59, SCT 125; mandible fragments SCT 16, SCT 50, SCT 51, SCT 58 + SCT 67, SCT 79, SCT 71, SCT 81, SCT 89, SCT 102, SCT 195.

Original diagnosis. See Mazza & Rustioni (2011).

Revised diagnosis. Parastyle and mesostyle very robust and paracone supported by prominent median rib. Weak external rib of metacone and weak metastyle. Upper molars very similar to one another, with trapezoidal, closely packed lingual crescents. Protocone somewhat smaller than metacone. Tiny entostyle on second molars. Lingual walls somewhat more corrugated than labial walls in upper check teeth, opposite in lower ones. Mandible with slightly sinuous horizontal ramus; marked mandibular scissure; premolars compressed mesiodistally and enlarged labiolingually; molars elongated mesiodistally and somewhat compressed labiolingually; paraconid absent or rudimentary; lingually open mesial fossette; metastylid and postentocristid strong; small ectostylid on each lower molar; third lower molars with wide, mesiolingually open mesial fossette; distal margin of hypoconulid separated from entoconulid occlusalward, and fused to it towards the collar; cementum occasionally present; cingula absent in lower cheek teeth; rugose enamel on lower molars.

Differential diagnosis. Differs from S. minutus  , S. falcidens  and S. apulicus  by its larger size and the presence of rugose lingual enamel on lower molars. Differs from S. falcidens  and S. apulicus  by rugose labial enamel on lower molars. Differs from S. minutus  , S. apulicus  and S. mazzai  by having mesodont molars. Differs from S. minutus  and S. falcidens  by absence of a cingulum on lower molars. Differs from S. falcidens  by the presence of a tiny entostyle on M 2. Differs from S. mazzai  by non-pachyostotic mandible, the presence of an ectostylid on lower molars and strong metastylids.

Derivation of name. From the Latin name of the region Abruzzo (central Italy).

Preservation and deposition of type specimens. Soprintendenza Archeologica dell’Abruzzo (Chieti, central Italy).

Type locality and horizon. Tortonian Scontrone Member of the Lithothamnium Limestone ( Patacca et al. 2008; 41 ° 45 ' 15.54 ''N, 14 °02' 13.14 ''E), outskirts of Scontrone, southern border of the National Park of Abruzzi, L’Aquila, central Italy.

Description. For original description of the holotype, see Mazza & Rustioni (2011 )). Morphological description of upper molars are erroneous, because the holotype is a mandible. Revised description: Mandible tapers abruptly rostrally. Fairly long diastema in front of p 2. Ventral profile markedly convex under the lateral dentition. Marked mandibular scissure. p 3 and p 4 short, somewhat compressed mesiodistally and enlarged labiolingually. Parastylid well developed, paraconid absent; weak, backward verging metaconid. Entoconid well developed and backward verging like metaconid. Entostylid very small. Vertical groove on the posterolingual region of p 4. Labial enamel wall rugose, lingual wall smooth. m 1 –m 2 elongated mesiodistally and somewhat compressed labiolingually. Labial conids markedly triangular. m 1 tightly in contact with p 4, mesial wall flattened, preprotocristid bent abruptly in lingual direction with marked angle. Premetacristid very sharp and prominent lingually. Metastylid and postentocristid also very sharp and prominent. Preprotocristid fused to premetaconid crista, and postprotocristid to pre-entocristid. Hypoconid isolated. Small ectostylids. Enamel rugose. Residual cementum. m 3 with tetraconid similar to that of m 2. Premetacristid bent lingually, and preprotocristid separated from it, mesial fossette thus wide and opened mesiolingually. Distal margins of hypoconulid and entoconulid separated occlusalwards and rapidly fused towards collar.

Additional characters shown by paratypes, revised after Mazza & Rustioni (2011). SCT 59 and SCT 125 are both fragmentary right maxillaries preserving only M 2 -M 3. All other paratypes are mandible fragments preserving various elements or their alveoles: SCT 16 (p 4 –m 3), SCT 50 (p 4 -m 3), SCT 51 (p 4, part of m 1), SCT 58 + SCT 67 (m 2), SCT 81 (m 1 –m 3), SCT 89 (m 1, m 2), SCT 102 (m 1 –m 3, alveoles of p 4 and (partial) p 3) and SCT 79, SCT 71, SCT 195 with unknown preservation (not described, not figured; likely small fragments). Wear stage not given in Mazza & Rustioni (2011). Occlusal surfaces of lower cheek teeth quite inclined outwards; inner cuspids sharp and pointed, whereas outer cuspids are affected by relatively higher degrees of wear; mesodont. M 2 –M 3. Molars very similar to one another. Both bear robust parastyles, even stronger mesostyles, as well as considerably developed labial rib of the paracone. Much weaker external rib of metacone and metastyles. Lingual crescents trapezoidal, and postprotocristae and postmetaconule cristae robust. M 3 with large metaconule. Cingula and cementum not present. Lingual crescents very closely spaced. Tiny entostyle in M 2. p 3 –p 4. Paraconid rudimentary in poorly worn specimens, obliterating as wear progresses (see, however, remark on wear stage above). m 1 –m 2. In unworn or moderately worn first lower molars, preprotocristid extended to contact premetaconid crista, and postprotocristid to contact preentocristid. As wear progresses, these structures normally fuse together, so that protoconid connects mesially with premetaconid crista, as well as distally with pre-entocristid. Hypoconid isolated from the other conids at most levels of wear; only in considerably worn specimens posthypocristid fused to postentocristid. Prehypocristid fused mesially to postprotocristid only in heavily worn teeth. Residual cementum on some specimens.

Measurements. See Table 2.

Kingdom

Animalia

Phylum

Chordata

Class

Mammalia

Order

Artiodactyla

Family

Hoplitomerycidae

Genus

Scontromeryx

Loc

Scontromeryx apruthiensis ( Mazza et Rustioni, 2011 )

Van Der Geer, Alexandra A. E. 2014

2014
Loc

Hoplitomeryx apruthiensis

Mazza & Rustioni 2011

2011
Loc

Hoplitomeryx

Leinders 1984

1984