''Hoplitomeryx'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

deer-like

ruminant Ruminants (suborder Ruminantia) are ungulate, hoofed herbivorous grazing or browsing mammals that are able to acquire nutrients from plant-based food by Enteric fermentation, fermenting it in a specialized stomach prior to digestion, principally ...

s which lived on the former Gargano Island during the

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

and the

Early Pliocene Early may refer to: History * The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.: ** Early Christianity ** Early modern Europe Places in the United States * Early, Iowa * Early, Texas * Early ...

, now a

peninsula A peninsula (; ) is a landform that extends from a mainland and is surrounded by water on most, but not all of its borders. A peninsula is also sometimes defined as a piece of land bordered by water on three of its sides. Peninsulas exist on all ...

on the east coast of South Italy. ''Hoplitomeryx'', also known as "prongdeer", had five horns and sabre-like upper canines similar to a modern

musk deer Musk deer can refer to any one, or all seven, of the species that make up ''Moschus'', the only extant genus of the family Moschidae. Despite being commonly called deer, they are not true deer belonging to the family Cervidae, but rather their fa ...

. Its fossilized remains were retrieved from the late 1960s onwards from reworked reddish, massive or crudely stratified silty-sandy clays (terrae rossae), which partially fill the paleo-karstic fissures in the

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...

limestone substrate and that are on their turn overlain by Late Pliocene-

Early Pleistocene The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time ...

sediments of a subsequently marine, shallow water and terrigenous origin. In this way a buried paleo

karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

originated. The fauna from the paleokarst fillings is known as ''

Mikrotia ''Mikrotia'' is an extinct rodent belonging to the Muridae. It lived during the upper Miocene (about 11.63 - 5 million years ago) and its fossil remains have been found in Italy ( Gargano). The type species is ''M. magna'', although two other sp ...

'' fauna after the endemic murid of the region (initially named "Microtia", with a c, but later corrected, because the genus ''

Microtia Microtia is a congenital deformity where the auricle (external ear) is underdeveloped. A completely undeveloped pinna is referred to as anotia. Because microtia and anotia have the same origin, it can be referred to as microtia-anotia. Microtia ...

'' was already occupied). Later, after the regression and continentalization of the area, a second karstic cycle started in the late Early Pleistocene, the neokarst, which removed part of the paleokarst fill.

Description

''Hoplitomeryx'' was a deer-like

with a pair of pronged horns above each orbit and one central nasal horn. Hoplitomerycids are not the only horned

deer Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer ...

; before the appearance of antlered deer, members of the deer family commonly had horns. Another left-over of this stage is ''

Antilocapra ''Antilocapra'' is a genus of the family Antilocapridae, which contains only a single living species, the pronghorn ''(Antilocapra americana)''. Another species, the Pacific pronghorn, lived in California during the Late Pleistocene and survive ...

'' of North America, the only survivor of a once successful group related to

Bovidae The Bovidae comprise the biological family of cloven-hoofed, ruminant mammals that includes cattle, bison, buffalo, antelopes, and caprines. A member of this family is called a bovid. With 143 extant species and 300 known extinct species, ...

. The diagnostic features of ''Hoplitomeryx'' are: one central nasal horn and a pair of pronged orbital horns, protruding canines, complete fusion of the navicocuboid with the

metatarsal The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the med ...

, distally closed metatarsal gully, a non-parallel-sided

astragalus ''Astragalus'' is a large genus of over 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae and the subfamily Faboideae. It is the largest genus of plants in terms of described species. The genus is native to tempe ...

, and an elongated

patella The patella, also known as the kneecap, is a flat, rounded triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint. The patella is found in many tetrapods, such as m ...

.(Van der Geer 2004)

Species

The ''Hoplitomeryx'' skeletal material forms a

heterogeneous Homogeneity and heterogeneity are concepts often used in the sciences and statistics relating to the uniformity of a substance or organism. A material or image that is homogeneous is uniform in composition or character (i.e. color, shape, siz ...

group, containing four size groups from tiny to huge; within the size groups different morphotypes may be present. All size groups share the same typical ''Hoplitomeryx'' features. The different size groups are equally distributed over the excavated fissures, and are therefore not to be considered chronotypes. The hypothesis of an

archipelago An archipelago ( ), sometimes called an island group or island chain, is a chain, cluster, or collection of islands, or sometimes a sea containing a small number of scattered islands. Examples of archipelagos include: the Indonesian Archi ...

consisting of different islands each with its own morphotype cannot be confirmed so far. The tiny and small specimens show

insular dwarfism Insular dwarfism, a form of phyletic dwarfism, is the process and condition of large animals evolving or having a reduced body size when their population's range is limited to a small environment, primarily islands. This natural process is disti ...

, but this cannot be said for the medium and huge specimens. Hoplitomeryx matthei - skull

The situation with several co-existing morphotypes on an island is paralleled by ''

Candiacervus ''Candiacervus'' is an extinct genus of deer native to Pleistocene Crete. Due to a lack of other herbivores, the genus underwent an adaptive radiation, filling niches occupied by other taxa on the mainland. Due to the small size of Crete, the gen ...

'' (

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

Crete Crete ( el, Κρήτη, translit=, Modern: , Ancient: ) is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, and ...

Greece Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with ...

). Opinions about its

taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

differ, and at present two models prevail: one

for eight morphotypes, or alternatively, two genera for five

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

. The second model is based upon limb proportions only, but these are invalid taxonomic features for island endemics, as they change under influence of environmental factors that differ from the mainland. Also in ''Hoplitomeryx'' the morphotypes differ in limb proportions, but here different ancestors are unlikely, because in that case they all ancestors must have shared the typical hoplitomerycid features. In ''

'' as well as in ''Hoplitomeryx'', the largest species is as tall as an elk, but gracile and slender. The large variation is instead explained as an example of adaptive radiation, starting when the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

ancestor colonized the island. The range of empty niches promoted its radiation into several trophic types, yielding a differentiation in ''Hoplitomeryx''. The shared lack of large mammalian

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s and the limited amount of food in all niches promoted the development of derived features in all size groups (apomorphies).

Notes

References

* De Giuli, C. & Torre, D. 1984a. Species interrelationships and evolution in the Pliocene endemic faunas of Apricena (Gargano Peninsula - Italy). Geobios, Mém. spécial, 8: 379–383. * De Giuli, C., Masini, F., Torre, D. & Boddi, V. 1986. Endemism and bio-chronological reconstructions: the Gargano case history. Bollettino della Società Paleontologica Italiana,25 (3): 267–276. Modena. * Dermitzakis, M. & De Vos, J. 1987. Faunal Succession and the Evolution of Mammals in Crete during the Pleistocene. Neues Jahrbuch Geologische und Paläontologische Abhandlungen 173, 3: 377–408. * De Vos, J. 1979. The endemic Pleistocene deer of Crete. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, Series B 82, 1: 59–90. * De Vos, J. & Van der Geer, A.A.E. 2002. Major patterns and processes in biodiversity: axonomic diversity on islands explained in terms of sympatric speciation. In: Waldren, B. & Ensenyat (eds.). World Islands in Prehistory, International Insular Investigations, V Deia International Conference of Prehistory. Bar International Series, 1095: 395–405. * Freudenthal, M. 1972: Deinogalerix koenigswaldi nov. gen., nov. spec., a giant insectivore from the Neogene of Italy.

Scripta Geologica ''Scripta Geologica'' is a peer-reviewed scientific journal that publishes on vertebrate and invertebrate palaeontology, palaeobotany/palynology, stratigraphy, petrology, and mineralogy, including gemmology with a focus on systematics. It is publis ...

14

(includes full text PDF) * Freudenthal, M. 1976. Rodent stratigraphy of some Miocene fissure fillings in Gargano (prov. Foggia, Italy).

37

(includes full text PDF) * Freudenthal, M. 1985. Cricetidae (Rodentia) from the Neogene of Gargano (Prov. of Foggia, Italy).

77

(includes full text PDF) * Leinders, J.J.M. 1984. Hoplitomerycidae fam. nov. (Ruminantia, Mammalia) from Neogene fissure fillings in Gargano (Italy); part 1: The cranial osteology of Hoplitomeryx gen. nov. and a discussion on the classification of pecoran families.

70: 1-51, 9 pl

(includes full text PDF) * Mazza, P. 1987. Prolagus apricenicus and Prolagus imperialis: two new Ochotonids (Lagomorpha, Mammalia) of the Gargano (Southern Italy). Bollettino della Società Paleontologica Italiana, 26 (3): 233–243. *MAZZA, P. P. A. and RUSTIONI, M. (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. Zoological Journal of the Linnean Society, 163: 1304–1333. * Parra, V., Loreau, M. & Jaeger, J.-J. 1999. Incisor size and community structure in rodents: two tests of the role of competition. Acta Oecologica, 20: 93–101. * Mazza P.P.A. 2015 Scontrone (central Italy), signs of a 9-million-year-old tragedy. Lethaia, 48: 387–404. * Mazza, P.P.A., Rossi M.A., Agostini S. (2015) Hoplitomeryx (Late Miocene, Italy), an example of giantism in insular ruminants. Journal of Mammalian Evolution 22: 271–277. * Mazza P. P. A., Rossi M.A., Rustioni M., Agostini S., Masini F. and Savorelli, A. (2016) Observations on the postcranial anatomy of Hoplitomeryx (Mammalia, Ruminantia, Hoplitomericidae) from the Miocene of the Apulia Platform (Italy). Palaeontographica, 307 (1-6): 105–147. * Van der Geer, A.A.E. 1999. On the astragalus of the Miocene endemic deer Hoplitomeryx from the Gargano (Italy). In: Reumer, J. & De Vos, J. (eds.). Elephants have a snorkel! Papers in honour of P.Y. Sondaar: 325–336. Deinsea 7. * Van der Geer, A.A.E. 2005. The postcranial of the deer Hoplitomeryx (Mio-Pliocene; Italy): another example of adaptive radiation on Eastern Mediterranean Islands. Monografies de la Societat d'Història Natural de les Balears 12: 325–336. * Van der Geer, A.A.E. 2005. Island ruminants and the evolution of parallel functional structures. In: Cregut, E. (Ed.): Les ongulés holarctiques du Pliocène et du Pléistocène. Actes Colloque international Avignon, 19-22 septembre. Quaternair, 2005 hors-série 2: 231–240. * Van der Geer, A.A.E. 2008. The effect of insularity on the Eastern Mediterranean early cervoid Hoplitomeryx: the study of the forelimb. Quaternary International, 182(1)145-159. * Van der Geer, A., Lyras, G., de Vos, J. & Dermitzakis M. 2010. Evolution of Island Mammals: Adaptation and Extinction of Placental Mammals on Islands. Oxford: Wiley-Blackwell Publishing.

External links

Research on Hoplitomeryx

Research on island faunas

Publications on Hoplitomeryx
{{Taxonbar, from=Q3786730 Prehistoric cervoids Miocene even-toed ungulates Pliocene even-toed ungulates Zanclean extinctions Extinct mammals of Europe Fossil taxa described in 1984 Prehistoric even-toed ungulate genera

Description

Species

See also

Notes

References

External links