Hoplitomeryx matthei Leinders 1983
Creators: name: Mazza, Paul P. A.
name: Rustioni, Marco
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Artiodactyla
Hoplitomerycidae
Hoplitomeryx
Hoplitomeryx matthei

description: HOPLITOMERYX MATTHEI LEINDERS, 1983   (TABLE 1, FIGS 3, 5)  
 Holotype: Skull RGM 260.965.   
 Paratypes: Skull fragments RGM 260.944, RGM 260.945 (Type II), RGM 261.092, RGM 261.093, RGM 260.933, RGM 261.100, RGM 261.096, RGM 261.102; nasal horncores: RGM 260.902 (Type II), RGM 260.898 (Type II?), RGM 260.922 (Type I), RGM 260.923 (Type I), RGM 261.098 (Type III); orbital horncores: RGM 261.097 (Type III), RGM 261.099 (Type IV), RGM 178.286 (Type?), RGM 260.926 (Type V).   
 Other specimens here ascribed to the species: Skull fragments SCT 17, RGM 178.566; hemimandibles SCT 80, SCT 83, SCT 72, RGM 261.140, RGM 261.110, RGM 260.943, RGM 260.952; RGM 178.376, RGM 178.474 (?), RGM 261.141, RGM 261.142, RGM 425.330, RGM 425.476, an uncatalogued juvenile mandible, an uncatalogued old aged mandible.   
 Type locality and horizon: Holotype from the Messinian karstic fissure filling called Pirro 11 A in the limestone quarry Pirro between Apricena and Poggio Imperiale, Foggia, Gargano promontory, southeastern Italy (41°48′12″N, 15°23′04″E). Paratypes tagged SCT from the Tortonian Scontrone Member of the Lithothamnium Limestone (Patacca et al., 2008; 41°45′15.54″N, 14°2′13.14″E), outskirts of Scontrone, southern border of the National Park of Abruzzi, L’Aquila, central Italy. Paratypes RGM 260.944, RGM 260.945, RGM 260.933, RGM 260.902, RGM 260.898, RGM 260.922, RGM 260.923, RGM 260.926, RGM 261.140, RGM 260.943, RGM 260.952, RGM 261.141, RGM 261.142, RGM 425.330 come from the Messinian karstic fissure filling called S. Giovannino in a homonymous limestone quarry; RGM 261.092, RGM 261.093, RGM 261.096, RGM 261.097 come from the Messinian karstic fissure filling called Nazario 4 in the limestone quarry Nazario; RGM 178.286 comes from the Messinian karstic fissure filling called Chiro 3, RGM 261.100 comes from the Messinian karstic fissure filling called Chiro D 4, RGM 178.376 comes from the Messinian karstic fissure filling called Chiro 10, RGM 425.476 comes from the Messinian karstic fissure filling called Chiro 10B, and RGM 178.474 comes from the Messinian karstic fissure filling called Chiro 17, all in the limestone quarry Chiro; RGM 178.566 comes from the Messinian karstic fissure filling called Pizzicoli 4 and RGM 261.099 comes from the Messinian karstic fissure filling called Pizzicoli 5, both in the limestone quarry Pizzicoli; RGM 261.110 comes from the Messinian karstic fissure filling called Pirro N A in the limestone quarry Pirro; RGM 261.102 comes from the Messinian karstic fissure filling called Gervasio in a homonymous limestone quarry; RGM 261.098 comes from the Messinian karstic fissure filling called Mobilio 1 in the limestone quarry Mobilio. All these quarries are located between Apricena and Poggio Imperiale, Foggia, Gargano promontory, south-eastern Italy (41°48′12″N, 15°23′04″E).   
 Preservation and deposition of the holotype and paratypes: Museum Naturalis, Leiden (the Netherlands).   
 Preservation and deposition of the new paratypes: Scontrone specimens: Soprintendenza Archeologica dell’Abruzzo (Chieti, central Italy); Gargano specimens: Museum Naturalis, Leiden (the Netherlands).   
 Etymology: Species dedicated to Matthijs Freudenthal.   
 Diagnosis: As opposed to Leinders’ (1983) original description, H. matthei has four orbital horns and no median horn. None of the specimens included in Leinders’ (1983) original description of the species show sabre-like upper canines, or alveoli of these teeth. The rest of the diagnosis of the cranial characters of the species is the same given by Leinders (1983). Here we add the diagnosis of the cheek teeth of the species. Dental apomorphies of species: mesodont lateral dentition (HI = 0.86); absence of upper canines; upper premolars and molars with prominent parastyles and less well-developed metastyles. Robust mesostyles on upper molars. Strong external paracone rib; labial wall of metacone almost flat. Upper molars with triangular protocone and trapezoidal metaconule. No entostyles. Mandibles with horizontal ramus pachyostotic, dorsoventrally deep under and just behind m3; cheek teeth with globose cuspids, especially lingually, and stylids not prominent; paraconid present in unworn or poorly worn lower premolars; ectostylid small in m1, absent in m2 and m3; third lower molars with crescent hypoconulid embracing tear-shaped entoconulid; distal margin of hypoconulid separated from entoconulid occlusalwards and fused to it towards the collar; labial enamel wall corrugated, lingual wall smoother; thin cementum cover; lower cingula absent. Lower dental formula in Gargano specimens: 2–3, unknown in Scontrone representatives at the moment.   
 Differential diagnosis: See Table 1.   
 Description of holotype: See Leinders’ (1983) original description.   
 Description of cheek teeth: The upper premolars of H. matthei are not preserved in the specimens now available. The upper molars have an enlarged mesial portion and a narrower distal part, caused by the triangular shape of the protocone and the more lateromedially squeezed, trapezoidal-shaped posterolingual cusp. The upper cheek teeth have well-developed spurs and their lingual crescents are narrowly cleft.   
Lower premolar to molar ratio (p3-p4/m1-m3) in the Gargano lower toothrows is 0.40–0.43, the highest of all the specimens from this locality. The lingual cuspids of the lower molars are globose. Stylids poorly developed, and quite more salient than the labial cuspids. Postentocristids well developed, but not protruding lingually. The third lower molars have a characteristically crescent hypoconulid extended to embrace the tear-shaped entoconulid.  
M1–M2–M3. Robust parastyle and mesostyle, weaker metastyle. External rib of paracone strong, metacone rib very weak. As wear progresses, preprotocrista fuses to preparacrista, and postmetaconule crista to postmetacrista. Spur present, grows progressively larger from M1 to M3. The latter tooth bears a large metaconule. Labial enamel wall is somewhat rougher than lingual one. No entostyles.  
p3–p4. Short mesiodistally and enlarged labiolingually. Paraconid present. Protoconid very prominent and salient. Talonid consisting of robust entoconid and small (p3) to large (p4) hypoconid. Metaconid very weak, practically represented only by postmetacristid which is fused to protoconid. Entostylid barely developed. No cingula. Enamel smooth.  
m1–m2. Labial cuspids fairly triangular, approximately all the same size but not very spaced from one another. Stylids not very prominent lingually; metastylid and entostylid somewhat stronger than parastylid. Ectostylid very small and short (m1) or completely absent (m2). Metaconid and entoconid globose at base. Preprotocristid short, fairly straight and not fused to premetacristid. Mesial fossette opened mesiolingually. Enamel smooth lingually, corrugated labially. Thin cementum in m2.  
m3. Labial cuspids triangular. Metaconid and entoconid swollen at base of crown. Mesial wall of tooth flattened, mesial stylid of protoconid bent in lingual direction with marked angle. The tooth thus appears somehow squeezed against the second lower molar. Metastylid and entostylid not prominent lingually, parastylid sharp and fairly strong, and protruding lingually. Preprotocristid and premetacristid fashioned as in the other molars; mesial fossette opened mesiolingually. Postentocristids not protruding lingually. Ectostylid absent. Distal margin of hypoconulid embraces the entoconulid. Hypoconulid separated from entoconulid generally almost down to base of crown. Enamel walls smooth lingually and corrugated labially. Thin cementum cover.  
 Description of the skull fragment SCT 17: The specimen is a left portion of a skull. It includes the orbital rim, part of the orbital horn cores, and a thin outer wall of the maxillary bone, with the very badly preserved buccal enamel surfaces of the cheek teeth. The specimen is so fragile that it could not be removed from the rock in which it is preserved. There is no evidence of the possible presence of the nasal horn core. The orbital horn cores show a combination of characters of Leinders’ (1983) horn core types 1 and 2. The lateral horn core springs outwards from a fairly high position of the supraorbital process of the frontal bone, as in horn core type 1. It lies on a plane at right angles to the sagittal plane, bends gently with a dorsal concavity, and is slightly compressed anterodorsally, as in horn core type 2. Although its tip is broken off, what remains of it proves that it bent backwards and somewhat medially, unlike any of Leinders’ (1983) horn core types. The medial horn core points backwards and slightly outwards as in horn core type 1. Medial and lateral horn cores have approximately the same diameters.   
 Measurements: See Table 2.
description: Published as part of Mazza, Paul P. A. & Rustioni, Marco, 2011, Five new species of Hoplitomeryx from the Neogene of Abruzzo and Apulia (central and southern Italy) with revision of the genus and of Hoplitomeryx matthei Leinders, 1983, pp. 1304-1333 in Zoological Journal of the Linnean Society 163 (4) on pages 1320-1322, DOI: 10.1111/j.1096-3642.2011.00737.x, http://zenodo.org/record/5442183