''Seazzadactylus'' is a basal

pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 to ...

genus that during the late

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

lived in the area of present

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

Discovery

In 1997, amateur paleontologist Umberto Venier discovered the skeleton of a pterosaur in a boulder laying in the bed of the Seazza brook, just before it joins the Tagliamento river, near Preone in the

Dolomites The Dolomites ( it, Dolomiti ; Ladin: ''Dolomites''; german: Dolomiten ; vec, Dołomiti : fur, Dolomitis), also known as the Dolomite Mountains, Dolomite Alps or Dolomitic Alps, are a mountain range located in northeastern Italy. They form par ...

. Venier brought the find to the '' Museo Friulano di Storia Naturale'' at

Udine Udine ( , ; fur, Udin; la, Utinum) is a city and ''comune'' in north-eastern Italy, in the middle of the Friuli Venezia Giulia region, between the Adriatic Sea and the Alps (''Alpi Carniche''). Its population was 100,514 in 2012, 176,000 with t ...

. After partial preparation paleontologist

Fabio Marco Dalla Vecchia Fabio is a given name descended from Latin ''Fabius'' and very popular in Italy and Latin America (due to Italian migration). Its English equivalent is Fabian. The name is written without an accent in Italian and Spanish, but is usually accented ...

announced the discovery in the scientific literature in 2000. In 2003, Dalla Vecchia referred the specimen to '' Eudimorphodon''. In 2009 however, further preparation made him conclude that it was a species new to science, not identical to either ''Eudimorphodon'' or '' Carniadactylus''. In 2019, Dalla Vecchia named and described the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

''Seazzadactylus venieri''. The generic name combines that of the Seazza with the Greek , 'finger'. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

honours Venier as discoverer. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

, MFSN 21545, was found in a layer of the Dolomia di Forni Formation dating from the middle to upper

Norian The Norian is a division of the Triassic Period. It has the rank of an age (geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic defi ...

. It consists of a partial skeleton with skull and lower jaws. The skeleton is not articulated but the bones are in close association. It lacks the tail and most feet bones. It represents a subadult individual, not fully grown.

Description

Dalla Vecchia established a number of

apomorphic In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...

traits. In the praemaxilla the teeth are limited to the front half of the body. The

jugal bone The jugal is a skull bone found in most reptiles, amphibians and birds. In mammals, the jugal is often called the malar or zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by species. Anatomy ...

has a high front branch, tapering to the front and below into a sharp needle-like point. The main body of the jugal bone is pierced in the middle by a large foramen. The front branch of the

pterygoid bone The pterygoid is a paired bone forming part of the palate of many vertebrates, behind the palatine bone In anatomy, the palatine bones () are two irregular bones of the facial skeleton in many animal species, located above the uvula in the th ...

makes a right angle to the outer side. The ectopterygoid bone is positioned behind the pterygoid and has a recurved outer side branch in the direction of the jugal as well as a rear branch. Teeth in the

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...

and the

dentary bone In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...

possess multiple cusps, sometimes as high as six or seven, while erupted teeth with three cusps are absent. The first, second and third maxillary teeth are recurved, with the curvature gradually diminishing along the series. The shoulder blade is fan-like expanded to the rear. The pteroid bone is small and slender, formed like an exclamation mark.

Phylogeny

''Seazzadactylus'' was placed in the Pterosauria in 2019, in a basal position outside of the

Monofenestrata Monofenestrata is an unranked group of pterosaurs that includes the family Wukongopteridae and the suborder Pterodactyloidea. The clade Monofenestrata was in 2009/2010 defined as the group consisting of ''Pterodactylus'' and all species sharing ...

. A cladistic analysis showed it was part of a yet-unnamed

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

also containing '' Arcticodactylus'', '' Austriadraco'', ''Carniadactylus'', '' Raeticodactylus'' and '' Caviramus''. This unnamed clade was eventually named as Caviramidae in a 2020 study by Matthew G. Baron.Matthew G. Baron (2020). "Testing pterosaur ingroup relationships through broader sampling of avemetatarsalian taxa and characters and a range of phylogenetic analysis techniques". PeerJ. 8: e9604. doi:10.7717/peerj.9604. PMC 7512134. . In the evolutionary tree ''Seazzadactylus'' would be positioned directly above ''Austriadraco'' and below ''Carniadactylus''. ''Eudimorphodon'' was not recovered as a close relative but in a more derived position instead, under '' Campylognathoides''.

Notes

{{Taxonbar, from=Q65952825 Late Triassic pterosaurs of Europe Fossil taxa described in 2019

Discovery

Description

Phylogeny

See also

Notes