The Trias greenfinch (''Chloris triasi'') is an extinct passerine from the family of

finch The true finches are small to medium-sized passerine birds in the family Fringillidae. Finches generally have stout conical bills adapted for eating seeds and nuts and often have colourful plumage. They occupy a great range of habitats where the ...

es (Fringillidae). The fossil remains were unearthed in the

Cuevas de los Murciélagos The Cuevas de los Murciélagos are a complex of two volcanic caves on La Palma, Canary Islands. They are located at the Nacientes de Marcos y Cordero (springs of Marcos and Cordero) near the municipality of San Andrés y Sauces San Andrés y Sau ...

near

San Andrés y Sauces San Andrés y Sauces is a municipality on the island of La Palma, Province of Santa Cruz de Tenerife, Canary Islands, Spain. It is situated in the northeastern part of the island. The population of the municipality is 4,473 (2013)< ...

in the north of

La Palma La Palma (, ), also known as ''La isla bonita'' () and historically San Miguel de La Palma, is the most northwesterly island of the Canary Islands, a Spanish autonomous community and archipelago in Macaronesia in the North Atlantic Ocean. La Pa ...

Canary Islands The Canary Islands (; ) or Canaries are an archipelago in the Atlantic Ocean and the southernmost Autonomous communities of Spain, Autonomous Community of Spain. They are located in the northwest of Africa, with the closest point to the cont ...

. The species epithet commemorates Spanish palaeontologist Miquel Trías who collected the holotype together with Josep Antoni Alcover in July 1985.

Description

The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

is an almost complete

cranium The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

with both pterygoids but lacking

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

quadrate bone The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids ( reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms up ...

s, and the

palatine process of maxilla In human anatomy of the mouth, the palatine process of maxilla (palatal process), is a thick, horizontal process of the maxilla. It forms the anterior three quarters of the hard palate, the horizontal plate of the palatine bone making up the rest ...

. The paratypes include a proximal fragment of a right

humerus The humerus (; : humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius (bone), radius and ulna, and consists of three sections. The humeral upper extrem ...

, a distal fragment of a right humerus with a prominent fragmented

epicondyle An epicondyle () is a rounded eminence on a bone that lies upon a condyle ('' epi-'', "upon" + ''condyle'', from a root meaning "knuckle" or "rounded articular area"). There are various epicondyles in the human skeleton The human skeleton is ...

, a left

ulna The ulna or ulnar bone (: ulnae or ulnas) is a long bone in the forearm stretching from the elbow to the wrist. It is on the same side of the forearm as the little finger, running parallel to the Radius (bone), radius, the forearm's other long ...

lacking the

epiphyseal plate The epiphyseal plate, epiphysial plate, physis, or growth plate is a hyaline cartilage plate in the metaphysis at each end of a long bone. It is the part of a long bone where new bone growth takes place; that is, the whole bone is alive, with ma ...

, an almost complete right ulna lacking the

olecranon The olecranon (, ), is a large, thick, curved bony process on the proximal, posterior end of the ulna. It forms the protruding part of the elbow and is opposite to the cubital fossa or elbow pit (trochlear notch). The olecranon serves as a lever ...

and a complete left

carpometacarpus The carpometacarpus is a bone found in the hands of birds. It results from the fusion of the carpal and metacarpal bone, and is essentially a single fused bone between the wrist and the knuckles. It is a smallish bone in most birds, generally fla ...

. The cranium length is 34,89 mm, the cranium width is 17,47 mm and the cranium height is 14,31 mm. The

maxilla In vertebrates, the maxilla (: maxillae ) 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 two maxil ...

length is 19,10 mm, the maxilla width is 9,67 mm, and the maxilla height is 6,71 mm. The interorbital width is 6,11 mm. The length of the carpometacarpus is 11,69 mm. The Trias greenfinch was closely related to the

European greenfinch The European greenfinch or simply the greenfinch (''Chloris chloris'') is a small passerine bird in the finch family Fringillidae. This bird is widespread throughout Europe, North Africa and Southwest Asia. It is mainly resident, but some norther ...

(''Chloris chloris''). However, its head was larger and broader and its bill was about 30 percent larger. Its legs were very long and robust, but compared to the greenfinch its wings were shorter. This might have been an adaption to more terrestrial habits in the

laurel forest Laurel forest, also called laurisilva or laurissilva, is a type of subtropical forest found in areas with high humidity and relatively stable, mild temperatures. The forest is characterized by broadleaf tree species with evergreen, glossy and el ...

Biology

Its large bill suggests the assumption that its main diet included large seeds. The shorter wings might have reduced its flight ability which wasn't necessary due to the lack of predators on La Palma.

Extinction

The fossil material is from layers which are dated to the

Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as the Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division ...

. However, it might have become extinct in the early Holocene when the first human settlers, accompanied by

cat The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the ...

s and

rat Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include '' Neotoma'' (pack rats), '' Bandicota'' (bandicoo ...

s, arrived at the Canary Islands.

References

*Josep Antoni Alcover & F. Florit: ''Una nueva especie de Carduelis (Fringillidae) de La Palma'' In: Vieraea 17 (1987):p 75-86 *Julian Pender Hume, Michael Walters: Extinct Birds. A & C Black, London 2012. :p 316 {{Taxonbar, from=Q1516212 Chloris (bird) Late Quaternary prehistoric birds Birds of the Canary Islands Holocene extinctions Fossil taxa described in 1987 Extinct birds of Atlantic islands