Herbertlutzius

Herbertlutzius
Temporal occurrence
Middle Eocene
44.7 to 43.4 million years
Locations
Eckfelder Maar
Systematics
Higher mammals (Eutheria) Laurasiatheria Artiodactyla (Artiodactyla) Dichobunidae Eurodexeinae Herbertlutzius
Scientific name
Herbertlutzius
Franzen , 2009

Herbertlutzius is an extinct genus from the order of the even-toed ungulate and is considered to be its smallest, so far discovered representative. So far it has only comedown to uson a single lower jaw fragment from the Eckfelder Maar in the Eifel . Like the entire fossil site, the lower jaw is placed in the late Middle Eocene and is therefore around 44 million years old. Herbertlutzius thus belongsto the early phase of the evolution of the ungulates.

features

Herbertlutzius is a very small, now extinct, arthropod and reached the size of a hedgehog . The genus has so far only been passed on through a single, left lower jaw fragment 1.9 cm long and 0.48 cm high, to which the last premolar and the first and parts of the second molar still adhere. In addition, the root of the third premolar is partially preserved. Since the teeth are clearly chewed, the animal was already fully grown at the time of its death. The molars were long and narrow. The anterior molar with 2.9 mm length was significantly shorter than the rearmost premolar with 3.4 mm, but exceeded this with 1.7 mm width compared to 1.4 mm in the fourth premolar. The chewing surfaces of the molars had a bumpy ( bunodontes ) enamel pattern . The trigonid was characteristically higher than the talonid , but both had about the same width and were open on the tongue. The yokes created by the paired arrangement of the enamel cusps had a distinctive (tapir-like) arrangement that ran transversely to the length of the tooth.

Based on the size of the fossil, especially the teeth, it is assumed that Herbertlutzius is one of the smallest cloven-hoofed animals known to date. Diacodexis from the Lower Eocene , whose European representatives had similarly long but wider molars, was similarly small , while the North American relatives were larger overall. Also Homacodon from the Geisel had similar dimensions. Here, however, the molars were significantly larger than the rearmost premolar, which, at 3.5 mm in length, was the size of Herbertlutzius' . Likewise, the closely related and roughly the same old Eygalayodon had significantly larger posterior molars and probably exceeded Herbertlutzius in body size.

Fossil record

So far only a single, left lower jaw fragment is known, which at the same time represents the holotype (copy number MNHM PW 1991/43-LS) and is kept in the State Collection for Natural History Rhineland-Palatinate . This was discovered back in 1991 during the annual excavations in the Eckfelder Maar , a very fossil-rich site in the Eifel , and thus, like the entire site, dates to the Middle Eocene around 44 million years ago. The fossil was found in a sediment body that was created by slope slides in the former maar lake ( turbidite ). Since further finds of this genus of cloven-hoofed animals were initially expected, the piece remained unprocessed for the time being and was only published in 1994.

Systematics

Herbertlutzius is an extinct genus from the order of the artifacts . It was first described in 1994 by Jens Lorenz Franzen as Lutzia . Since the name has been preoccupied by a representative from the mosquito group since 1903 , Franzen changed it to Herbertlutzius in 2009 . Both names honor Herbert Lutz from the Mainz Natural History Museum for his services to research into the Eckfelder Maar fossil deposit . Only recognized type is Herbertlutzius eckfeldensis , the species epithet in turn refers to the reference. In his first description, Franzen placed Herbertlutzius in the family of the Diacodexeidae , very primitive and mostly small cloven-hoofed animals, which are at the base of this mammalian order and are characterized by a rather short snout. A revision of the early even-toed ungulates makes a position within the family Dichobunidae and here in the subfamily Eurodexeinae appear more plausible. Although these are closely related to the Diacodexeidae, they represent a separate line of development of the early cloven-hoofed animals, which is more restricted to Eurasia . As a result, there is a closer relationship with Eurodexis and Eygalayodon .

Individual evidence

1. ↑ Herbert Frankenhäuser, Werner Löhnertz, Jens L. Franzen, Uwe Kaufluss, Martin Koziol Herbert Lutz, Dieter F. Mertz, Jens Mingram, Torsten wappler and: Volker Wilde: The Eckfelder Maar in the Vulkaneifel - a window into a habitat off the coast 44 million years ago . Mainz Natural Science Archive 47, 2009, pp. 263–324
2. ↑ ^{a b c d} Jens Lorenz Franzen: New mammal finds from the Eocene of the Eckfelder Maar near Manderscheid (Eifel). Mainzer Naturwissenschaftliches Archiv, supplement 16, 1994, pp. 189–211
3. ↑ ^{a b c} Jessica M. Theodor, Jörg Erfurt and Grégoire Métais: The earliest Artiodactyls. In: Donald R. Prothero and Scott E. Foss (Eds.): The Evolution of Artiodactyls. Johns Hopkins University, Baltimore, 2007, pp. 32-58
4. ↑ Jens Lorenz Franzen: Correction - Correction Herbertlutzius nomen novum instead of Lutzia Franzen, 1994. Mainzer Naturwissenschaftliches Archiv 47, 2009, pp. 325–326