Schizogalerix, Engesser, 1980

Rzebik-Kowalska, Barbara & Rekovets, Leonid I., 2016, New data on Eulipotyphla (Insectivora, Mammalia) from the Late Miocene to the Middle Pleistocene of Ukraine, Palaeontologia Electronica 12 (1), pp. 1-31 : 3-6

Genus SCHIZOGALERIX Engesser, 1980

Schizogalerix sp.

Figure 2.1-2.5

Material. Popovo 3 ( MN 11), right P4, left m1, right m2. MNI = 1. Catalogue number 29/III/1. Verkhnya Krynitsa 2 ( MN 11/ MN 12), left m1, left buccal fragment of P4, right m2. MNI = 1. Catalogue number 29/2/1.

Description. The anterior and posterior sides of the P4 ( Figure 2.1 ) are almost straight (not concave as typical for an upper P4). Its parastyle is vestigial in the tooth from Popovo 3 and slightly larger (in the shape of the cingulum cuspule) in Verkhnya Krynitsa 2. The paracone of P4 is strong, its protocone is also strong and larger than the hypocone. Cingula are absent except for antero-buccal and posterior ones. The m1 ( Figure 2.2-4 ) has a clear paraconid and massive metaconid standing slightly anterior to the protoconid. The posterior cingulid is connected with the posterior arm of the entoconid and the hypoconid. The rather narrow anterior cingulid continues to the buccal side and finishes below the protoconid/ hypoconid valley. The m2 ( Figure 2.5 ) is similar but smaller.

Measurements. See Table 1.

Systematic Position and Distribution. The relatively small size of the teeth indicates that they belong to Galericinae hedgehogs. In Europe the subfamily is comprised of seven genera. These include the Miocene (MN2/MN3–MN9 or MN10) Galerix Pomel, 1848 ( Murelaga et al. 2004; van den Hoek Ostende and Furió, 2005), Lantanotherium Filhol, 1888 (MN3/MN4- MN11, van den Hoek Ostende et al., 2005) as well as the rare early Middle Miocene (MN3) Riddleria van den Hoek Ostende, 2003 and the Late Miocene Deinogalerix Freudenthal, 1972 and Apulogalerix Masini and Fanfani, 2013 . Two genera - Parasorex von Meyer, 1865 (MN7+8–MN14, van den Hoek Ostende, 2001) and Schizogalerix Engesser, 1980 (MN5– MN15, Doukas, 2005) are also recorded from the Early Pliocene.

A comparison of Ukrainian hedgehog teeth with those of Riddleria is difficult because the lower molars of the latter form are damaged. The detailed morphology of their posterior walls is unclear and their measurements imprecise. Moreover, upper teeth characteristic of the genus Riddleria are absent in Ukrainian material (except for P4 which in Riddleria is fragmentary). So far Riddleria is known only from its type locality in Spain and dated to the early Middle Miocene; its presence in Ukraine is improbable. Even more unlikely are the very large representatives of the genus Deinogalerix and small representatives of the genus Apulogalerix . They are not found beyond the Gargano Peninsula ( Italy). Also, the lower molars (m1 and m2) of Apulogalerix lack a connection between the posterior arm of the hypocone and posterior cingulid.

Lanthanotherium species have massive teeth, the metaconid of their m1 stands in front of the protoconid, the entocristid of m1 and m2 extends anteriorly and the trigonids of their lower molars (m1 and m2) are significantly longer than the talonids. The Ukrainian molars from Popovo 3 and Verkhnya Krynitsa 2 are not very heavy, the metaconid of their m1 stands slightly anteriorly in comparison with the protoconid, and their trigonids are not much longer than talonids. In the m1 the difference between the trigonid and talonid lengths equals 0.37–0.38 mm (n=2) and in m2 it is 0.30 mm (n=2). In Lanthanotherium sansaniense ( Lartet, 1851) this difference equals 0.76–0.78 mm in m1 and 0.35– 0.41 mm in m2 (calculated from minimum, average and maximum lengths of these teeth cited by Baudelot, 1972). In Parasorex species there is no connection between the posterior cingulids and the posterior arm of the entoconid in lower molars while in teeth from Popovo 3 and Verkhnya Krynitsa 2 this connection is very clear. It is also present in the molars of Schizogalerix and just this character allowed the inclusion of Ukrainian molars to the genus Schizogalerix .

According to van den Hoek Ostende (2001) a connection between the posterior cingulid and the posterior arm of the entoconid is also visible in populations of Galerix symeonidisi Doukas, 1983 from Aliveri ( Greece, MN4) and from several localities in Germany (MN4, MN5) ( Doukas, 1986; Ziegler and Fahlbusch, 1986; Prieto and Rummel, 2009) but it is not present in younger (Middle and Late Miocene) species of this genus (compare with van den Hoek Ostende and Doukas, 2003).

So far more than 10 named species of Schizogalerix have been described in Europe ( Rzebik-Kowalska and Lungu, 2009). One of them, S. sarmaticum ( Lungu, 1981) was cited from Ukraine [Mikhailovka 1 (MN10) and Frunzovka 2 (MN11)]. However, the specimens described above cannot belong to S. sarmaticum because the P4 of the latter form is characterized by a large parastyle (vestigial in the specimen from Popovo 3 and Verkhnya Krynitsa 2) and very long entoconids and entostylids in lower molars (entostylids are lacking in Popovo 3).

All species of the genus Schizogalerix are more or less similar in size (Rzebik-Kowalska, 2009). From the morphological point of view the P4 from Ukrainian localities is very similar (by its almost straight anterior and posterior sides of the crown) to the P4 of S. anatolica from Turkey (MN7+8, Engesser, 1980) and especially to P4 of S. moedlingensis from Austria (MN11, Rabeder, 1973). The age and geographical distribution of the Ukrainian specimens are closer to the age and distribution of S. moedlingensis . However, material from Popovo 3 and Verkhnya Krynitsa 2 is too poor to allow species identification.

Representatives of the genus Schizogalerix were collected in neighboring countries such as the Republic of Moldova ( Lungu, 1981; Rzebik-Kowalska and Lungu, 2009; Lungu and Rzebik-Kowalska, 2011), Romania ( Rzebik-Kowalska, 2005) and Slovakia ( Fejfar and Sabol, 2005) as well as in other European countries (Rzebik-Kowalska, 2009), Asia minor , Engesser, 1980; Sen, 1990; Selänne, 2003; de Bruijn et al., 2006; Furió et al., 2014), China ( Qiu and Storch, 2005) and North Africa ( Algeria and Morocco; Engesser, 1980; Stoetzel, 2013).

Figures

FIGURE 2. Schizogalerix sp. from Popovo 3 (1) and Verkhnya Krynitsa 2 (2-5). 1, right P4, occlusal view (catalogue number 29/III/1/1). (2-4) left m1; 2, occlusal; 3, lingual; 4, posterior view (c.n. 29/2/1/1); 5, right m2; occlusal view (c.n. 29/2/1/2).