Saint Croix Macaw
Encyclopedia
The Saint Croix Macaw is an extinct species of parrot from the Caribbean islands of Saint Croix
and Puerto Rico
. It was originally described by Alexander Wetmore
in 1937 based on a subfossil limb bone unearthed by L. J. Korn in 1934 from a kitchen midden
at an Amerindian archeological sites on Saint Croix. A second specimen was described by Storrs L. Olson
and Edgar J. Máiz López based on various limb and shoulder bones excavated from a similar site on Puerto Rico, while a possible third specimen from Montserrat
has been reported. The species is one of two medium-sized macaw
s of the Caribbean, the other being the smaller Cuban Red Macaw
(Ara tricolor). Its bones are distinct from Amazon parrot
s as well as from the other medium-sized but geographically distant Lear's Macaw
(Anodorhynchus leari) and Blue-throated Macaw
(Ara glaucogularis). The natural range is unknown because parrots were regularly traded between islands by indigenous people. Like other parrot species in the Caribbean, the extinction of the Saint Croix Macaw is believed to be linked to the arrival of humans in the region.
named the species autocthones. An alternative incorrect spelling is autochthones, which comes from the Ancient Greek
word autochthōn (αὐτός—autos "self" and χθών—chthōn "earth") meaning "born of the earth". Misspellings of a name are termed as lapsus
(an accidental misspelling). An obvious error in the original publication containing the description of a species may be corrected by a later "emendation" with suitable justification.
based on a single tibiotarsus
, a placement confirmed by Olson who reexamined the bone. The discovery of a second specimen by Máiz López at Puerto Rico consisting of several bones confirmed this placement. The Saint Croix Macaw is distinguished from other macaws because of the intermediate size of the tibiotarsus and carpometacarpus
. Olson and Máiz López determined that the size of this species is only comparable to geographically distant macaws, namely the Lear's Macaw
(Anodorhynchus leari) from Brazil
and the Blue-throated Macaw
(Ara glaucogularis) from Bolivia
. Their detailed analysis of these and the other bones showed distinct differences from those species, particularly from the genus Anodorhynchus. Based on this, authorities generally recognize the Saint Croix Macaw as a valid species.
File:Macaw-bone-sizes.svg|thumb|right|upright=1.2|Mean length and ranges of carpometacarpus (yellow squares, Olson 2008.) and tibiotarsus (green circles, Olson 2008 and red circles, Wetmore 1937.) of all macaws. With links to the species; click on the double-rectangle icon
for image.
rect 0 0 1000 46 Hyacinth Macaw
rect 0 46 1000 92 Great Green Macaw
rect 0 92 1000 138 Red-and-green Macaw
rect 0 138 1000 184 Scarlet Macaw
rect 0 184 1000 230 Military Macaw
rect 0 230 1000 276 Blue-and-yellow Macaw
rect 0 276 1000 322 Lear's Macaw
rect 0 322 1000 368 Saint Croix Macaw
rect 0 368 1000 414 Blue-throated Macaw
rect 0 414 1000 460 Red-fronted Macaw
rect 0 460 1000 506 Cuban Red Macaw
rect 0 506 1000 552 Chestnut-fronted Macaw
rect 0 552 1000 598 Spix's Macaw
rect 0 598 1000 644 Blue-headed Macaw
rect 0 644 1000 690 Red-bellied Macaw
rect 0 690 1000 736 Golden-collared Macaw
rect 0 736 1000 782 Blue-winged Macaw
rect 0 782 1000 828 Red-shouldered Macaw
(Ara tricolor) are the only two Caribbean macaw species that have been described based on physical remains. In addition, seven entirely hypothetical extinct macaw species
from various Caribbean islands have been described based only on written accounts. Of the hypothetical species, the geographically nearest range is of the Lesser Antillean Macaw
(Ara guadeloupensis) from Guadeloupe
. According to Wetmore, taxonomic affinities with these hypothetical extinct species are unknown.
left tibiotarsus (holotype
, USNM
483530) described by Wetmore was of an immature but full-grown bird. Wetmore described the bone as similar to the tibiotarsus of Ara tricolor, with a larger transverse width, but more slender compared with larger macaws. The slender proportions of the bone and more elongated ridges about the proximal end distinguish the species from the Amazon parrots.
The bones found by Máiz López (USNM 448344) include the left coracoid (missing a portion of the bones head), the proximal and distal ends of the left humerus
, the proximal end of the right radius
, the left carpometacarpus
(missing one metacarpal), the left femur
(lacking the distal end), the right tibiotarsus (lacking part of the proximal articular surface), and the proximal fragment and worn distal portion of the left tibiotarsus.
Olson and Máiz López examined the bones and showed that they differed from Amazon parrot bones. The tibiotarsus has a narrower internal condyle (the round prominences at the end of a bone) and a distinctive inner cnemial crest
(a ridge at the front side of the head) that is more pointed and extends further proximally. The carpometacarpus is proportionally much longer with a process
on the alular metacarpal
that is not curved proximally. The femur has a proportionally larger head while the ectepicondylar process
(a bony elevation) and the attachment of pronator brevis
(one of the two pronation muscles in the wing) on the humerus are more proximal. The elongated coracoid has a relatively narrow shaft and the ventral lip of the glenoid facet (equivalent to the glenoid fossa
of mammals) is more protruded.
Olson and Máiz López showed that the Saint Croix Macaw is within the same size range as the Blue-throated Macaw and the Lear's Macaw. The length of the tibiotarsus is shorter than in the Blue-throated Macaw but longer than in the Lear's Macaw, while the lengths of the coracoid, carpometacarpus, and femur are smaller. In addition to the size, they observed that the pectoral attachment on the humerus is less excavated while the capital groove (a groove separating two parts of the head of the humerus) is wider; the head of the femur is more massive and when seen from the posterior side, more excavated under the head, neck, and trochanter
. Furthermore, the more robust shaft of the femur sets it specifically apart from the Lear's Macaw while the tibiotarsus is more robust with a flared distal extremity.
Amerindian village site near the current town of Concordia
, near the Southwest Cape. The bones from Puerto Rico were excavated from an inland village of the Saladoid
Indians that was located at the eastern bank of the Río Bucaná
, north-east of the current city of Ponce
. A possible third location is Montserrat, where a nearly complete coracoid was excavated (UF
4416). The bone of this specimen is slightly smaller than the bone of the Puerto Rico specimen, and could therefore be within the range of the Cuban Red Macaw (Ara tricolor); it has not been assigned to either species.
Although the species had only been found in St. Croix and Puerto Rico, in both cases it was recovered from Amerindian village sites. Williams and Steadman consider it possible that the species may have been native to St. Croix, but Olson and Máiz López regard this as unlikely, noting that parrots, important to the indigenous people, were likely to have been transported between islands. This makes it difficult to determine the natural geographical origins of the parrots known only from subfossil remains found in the West Indian region.
(dump for domestic waste) near Concordia, Saint Croix, without specifying the age of the bone.
In 1987, Máiz López found several bones of a single bird at the Hernández Colón archeological site on the eastern bank of the Río Bucaná
in south central Puerto Rico The archeological side in the semi-arid southern foothills
is a pre-Columbian Saladoid
village of approximately 15,000 m2 (3.7 acres) situated on an alluvial terrace. Máiz López found the bones in a kitchen midden in the layer that corresponded with the base and beginning of the Pomarrosa phase, which is stylistically related to the Hacienda Grande ceramic style that lasted globally from about 200 BCE
to 400 CE
. Radiocarbon dating
of charcoal samples indicate that the Pomarrosa phase started locally around 300 CE.
Saint Croix, U.S. Virgin Islands
Saint Croix is an island in the Caribbean Sea, and a county and constituent district of the United States Virgin Islands , an unincorporated territory of the United States. Formerly the Danish West Indies, they were sold to the United States by Denmark in the Treaty of the Danish West Indies of...
and Puerto Rico
Puerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
. It was originally described by Alexander Wetmore
Alexander Wetmore
Frank Alexander Wetmore was an American ornithologist and avian paleontologist.-Life:Wetmore studied at the University of Kansas...
in 1937 based on a subfossil limb bone unearthed by L. J. Korn in 1934 from a kitchen midden
Midden
A midden, is an old dump for domestic waste which may consist of animal bone, human excrement, botanical material, vermin, shells, sherds, lithics , and other artifacts and ecofacts associated with past human occupation...
at an Amerindian archeological sites on Saint Croix. A second specimen was described by Storrs L. Olson
Storrs L. Olson
Storrs Lovejoy Olson is an American biologist and ornithologist from the Smithsonian Institution. He is one of the world's foremost avian paleontologists....
and Edgar J. Máiz López based on various limb and shoulder bones excavated from a similar site on Puerto Rico, while a possible third specimen from Montserrat
Montserrat
Montserrat is a British overseas territory located in the Leeward Islands, part of the chain of islands called the Lesser Antilles in the West Indies. This island measures approximately long and wide, giving of coastline...
has been reported. The species is one of two medium-sized macaw
Macaw
Macaws are small to large, often colourful New World parrots. Of the many different Psittacidae genera, six are classified as macaws: Ara, Anodorhynchus, Cyanopsitta, Primolius, Orthopsittaca, and Diopsittaca...
s of the Caribbean, the other being the smaller Cuban Red Macaw
Cuban Red Macaw
The Cuban Red Macaw, Ara tricolor, is an extinct species of parrot that was native to Cuba and the Isla de la Juventud, an island off the coast of west Cuba. At about long it was one of the smaller members of the Ara genus of macaws. It was the last species of macaw native to the Caribbean...
(Ara tricolor). Its bones are distinct from Amazon parrot
Amazon parrot
Amazon parrot is the common name for a parrot of the genus Amazona. These are medium-size parrots native to the New World ranging from South America to Mexico and the Caribbean....
s as well as from the other medium-sized but geographically distant Lear's Macaw
Lear's Macaw
The Lear's Macaw , also known as the Indigo Macaw, is a rare Brazilian parrot with a highly restricted range. It is metallic blue with a faint, often barely visible, tinge of green, and a yellow patch of skin at the base of the heavy, black bill. It weighs around 950 g and is 75 cm long...
(Anodorhynchus leari) and Blue-throated Macaw
Blue-throated Macaw
The Blue-throated Macaw is a macaw endemic to a small area of north-central Bolivia known as Los Llanos de Moxos. Recent population and range estimates suggests that about 100-150 individuals remain in the wild. The main causes of their demise is capture for the pet trade and land clearance on...
(Ara glaucogularis). The natural range is unknown because parrots were regularly traded between islands by indigenous people. Like other parrot species in the Caribbean, the extinction of the Saint Croix Macaw is believed to be linked to the arrival of humans in the region.
Name and etymology
Alexander WetmoreAlexander Wetmore
Frank Alexander Wetmore was an American ornithologist and avian paleontologist.-Life:Wetmore studied at the University of Kansas...
named the species autocthones. An alternative incorrect spelling is autochthones, which comes from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
word autochthōn (αὐτός—autos "self" and χθών—chthōn "earth") meaning "born of the earth". Misspellings of a name are termed as lapsus
Lapsus
A lapsus is an involuntary mistake made while writing or speaking. According to Freud's early psychoanalytic theory, a lapsus represents a missed deed that hides an unconscious desire....
(an accidental misspelling). An obvious error in the original publication containing the description of a species may be corrected by a later "emendation" with suitable justification.
Taxonomy
Wetmore placed the Saint Croix Macaw in the macaw genus AraAra (genus)
Ara is a Neotropical genus of macaws with eight extant species and at least two extinct species. The genus name was coined by French naturalist Bernard Germain de Lacépède in 1799. It gives its name to and is part of the Arini, or tribe of Neotropical parrots. The Ara macaws are large striking...
based on a single tibiotarsus
Tibiotarsus
The tibiotarsus is the large bone between the femur and the tarsometatarsus in the leg of a bird. It is the fusion of the proximal part of the tarsus with the tibia.A similar structure also occurred in the Mesozoic Heterodontosauridae...
, a placement confirmed by Olson who reexamined the bone. The discovery of a second specimen by Máiz López at Puerto Rico consisting of several bones confirmed this placement. The Saint Croix Macaw is distinguished from other macaws because of the intermediate size of the tibiotarsus and carpometacarpus
Carpometacarpus
The carpometacarpus is the fusion of the carpal and metacarpal bone, essentially a single fused bone between the wrist and the knuckles. It is a smallish bone in most birds, generally flattened and with a large hole in the middle. In flightless birds, however, its shape may be slightly different,...
. Olson and Máiz López determined that the size of this species is only comparable to geographically distant macaws, namely the Lear's Macaw
Lear's Macaw
The Lear's Macaw , also known as the Indigo Macaw, is a rare Brazilian parrot with a highly restricted range. It is metallic blue with a faint, often barely visible, tinge of green, and a yellow patch of skin at the base of the heavy, black bill. It weighs around 950 g and is 75 cm long...
(Anodorhynchus leari) from Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
and the Blue-throated Macaw
Blue-throated Macaw
The Blue-throated Macaw is a macaw endemic to a small area of north-central Bolivia known as Los Llanos de Moxos. Recent population and range estimates suggests that about 100-150 individuals remain in the wild. The main causes of their demise is capture for the pet trade and land clearance on...
(Ara glaucogularis) from Bolivia
Bolivia
Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...
. Their detailed analysis of these and the other bones showed distinct differences from those species, particularly from the genus Anodorhynchus. Based on this, authorities generally recognize the Saint Croix Macaw as a valid species.
File:Macaw-bone-sizes.svg|thumb|right|upright=1.2|Mean length and ranges of carpometacarpus (yellow squares, Olson 2008.) and tibiotarsus (green circles, Olson 2008 and red circles, Wetmore 1937.) of all macaws. With links to the species; click on the double-rectangle icon
rect 0 0 1000 46 Hyacinth Macaw
Hyacinth Macaw
The Hyacinth Macaw , or Hyacinthine Macaw, is a parrot native to central and eastern South America. With a length of about 100 cm it is longer than any other species of parrot...
rect 0 46 1000 92 Great Green Macaw
Great Green Macaw
The Great Green Macaw, Ara ambiguus, also known as Buffon's Macaw or the Great Military Macaw, is a Central and South American parrot found in Nicaragua, Honduras, Costa Rica, Panama, Colombia and Ecuador. Two allopatric subspecies are recognized, the nominate subspecies is found in Central America...
rect 0 92 1000 138 Red-and-green Macaw
Red-and-green Macaw
The Red-and-green Macaw , also known as the Green-winged Macaw, is a large mostly-red macaw of the Ara genus.This is the largest of the Ara genus, widespread in the forests and woodlands of northern and central South America...
rect 0 138 1000 184 Scarlet Macaw
Scarlet Macaw
The Scarlet Macaw is a large, colorful macaw. It is native to humid evergreen forests in the American tropics. Range extends from extreme south-eastern Mexico to Amazonian Peru, Bolivia and Brazil in lowlands up to up to...
rect 0 184 1000 230 Military Macaw
Military Macaw
The Military Macaw is a large parrot and a medium-sized member of the macaw genus. Though considered vulnerable as a wild species, it is still commonly found in the pet trade industry. A predominantly green bird, it is found in the forests of Mexico and South America.-Taxonomy:There are three...
rect 0 230 1000 276 Blue-and-yellow Macaw
Blue-and-yellow Macaw
The Blue-and-Yellow Macaw , also known as the Blue-and-Gold Macaw, is a member of the group of large Neotropical parrots known as macaws. It breeds in forest and woodland of tropical South America from Trinidad and Venezuela south to Peru, Brazil, Bolivia, and Paraguay...
rect 0 276 1000 322 Lear's Macaw
Lear's Macaw
The Lear's Macaw , also known as the Indigo Macaw, is a rare Brazilian parrot with a highly restricted range. It is metallic blue with a faint, often barely visible, tinge of green, and a yellow patch of skin at the base of the heavy, black bill. It weighs around 950 g and is 75 cm long...
rect 0 322 1000 368 Saint Croix Macaw
Saint Croix Macaw
The Saint Croix Macaw is an extinct species of parrot from the Caribbean islands of Saint Croix and Puerto Rico. It was originally described by Alexander Wetmore in 1937 based on a subfossil limb bone unearthed by L. J. Korn in 1934 from a kitchen midden at an Amerindian archeological sites on...
rect 0 368 1000 414 Blue-throated Macaw
Blue-throated Macaw
The Blue-throated Macaw is a macaw endemic to a small area of north-central Bolivia known as Los Llanos de Moxos. Recent population and range estimates suggests that about 100-150 individuals remain in the wild. The main causes of their demise is capture for the pet trade and land clearance on...
rect 0 414 1000 460 Red-fronted Macaw
Red-fronted Macaw
The Red-fronted Macaw, Ara rubrogenys, is a parrot endemic to a small semi-desert mountainous area of Bolivia. It is highly endangered, and there may only be 150 or so birds left in the wild; it has been successfully bred in captivity, and is available, if not common, as a pet.-Description:The...
rect 0 460 1000 506 Cuban Red Macaw
Cuban Red Macaw
The Cuban Red Macaw, Ara tricolor, is an extinct species of parrot that was native to Cuba and the Isla de la Juventud, an island off the coast of west Cuba. At about long it was one of the smaller members of the Ara genus of macaws. It was the last species of macaw native to the Caribbean...
rect 0 506 1000 552 Chestnut-fronted Macaw
Chestnut-fronted Macaw
The Chestnut-fronted Macaw or Severe Macaw is one of the largest of the Mini-Macaws. It reaches a size of around of which around half is the length of the tail....
rect 0 552 1000 598 Spix's Macaw
Spix's Macaw
Spix's Macaw is the only member of the parrot genus Cyanopsitta. They are critically endangered, possibly extinct in the wild The species is conserved through several breeding programs. It was found in Brazil, in parts of the Brazilian state of Bahia...
rect 0 598 1000 644 Blue-headed Macaw
Blue-headed Macaw
The Blue-headed Macaw or Coulon's Macaw is native to eastern Peru , north-western Bolivia , and far western Brazil...
rect 0 644 1000 690 Red-bellied Macaw
Red-bellied Macaw
The Red-bellied Macaw, Orthopsittaca manilata, is a medium-sized, mainly green parrot. It is the only species of the genus Orthopsittaca, and it does not have any subspecies....
rect 0 690 1000 736 Golden-collared Macaw
Golden-collared Macaw
The Golden-collared Macaw or Yellow-collared Macaw is a small species of macaw belonging to the parrot family Psittacidae. It is native to central South America. In recent years it has often been placed in the genus Propyrrhura, but this is incorrect as per ICZN rules...
rect 0 736 1000 782 Blue-winged Macaw
Blue-winged Macaw
The Blue-winged Macaw , in aviculture more commonly known as Illiger's Macaw, is a species of macaw found in central and eastern South America. It was previously placed in the genus Ara or Propyrrhura. Blue-winged Macaws have been known to reach an age of 50–60 years.- Description:It has a total...
rect 0 782 1000 828 Red-shouldered Macaw
Red-shouldered Macaw
The Red-shouldered Macaw is the smallest macaw being 30–35 centimetres in length. It is a parrot native to the tropical lowlands, savannah, and swamplands of Venezuela, the Guianas, Bolivia, Brazil, and far south-eastern Peru...
Cuban Red Macaw
The Cuban Red Macaw, Ara tricolor, is an extinct species of parrot that was native to Cuba and the Isla de la Juventud, an island off the coast of west Cuba. At about long it was one of the smaller members of the Ara genus of macaws. It was the last species of macaw native to the Caribbean...
(Ara tricolor) are the only two Caribbean macaw species that have been described based on physical remains. In addition, seven entirely hypothetical extinct macaw species
Hypothetical extinct species
Several extinct species have been postulated, but owing to a lack of evidence they can only be regarded as hypothetical extinct species. They have caused confusion, as they may have been a separate species, a subspecies, or an introduced species.-Parrots:...
from various Caribbean islands have been described based only on written accounts. Of the hypothetical species, the geographically nearest range is of the Lesser Antillean Macaw
Lesser Antillean Macaw
The Lesser Antillean Macaw also known as Guadeloupe Macaw is a hypothetical extinct species of macaw species from the Antilles island of Guadeloupe. It was first described in detail by Jean-Baptiste Du Tertre in 1654 and 1657 and later in 1742 by Jean Baptiste Labat...
(Ara guadeloupensis) from Guadeloupe
Guadeloupe
Guadeloupe is an archipelago located in the Leeward Islands, in the Lesser Antilles, with a land area of 1,628 square kilometres and a population of 400,000. It is the first overseas region of France, consisting of a single overseas department. As with the other overseas departments, Guadeloupe...
. According to Wetmore, taxonomic affinities with these hypothetical extinct species are unknown.
Description
The subfossilSubfossil
Subfossil refers to remains whose fossilization process is not complete, either for lack of time or because the conditions in which they were buried were not optimal for fossilization....
left tibiotarsus (holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
, USNM
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. Admission is free and the museum is open 364 days a year....
483530) described by Wetmore was of an immature but full-grown bird. Wetmore described the bone as similar to the tibiotarsus of Ara tricolor, with a larger transverse width, but more slender compared with larger macaws. The slender proportions of the bone and more elongated ridges about the proximal end distinguish the species from the Amazon parrots.
The bones found by Máiz López (USNM 448344) include the left coracoid (missing a portion of the bones head), the proximal and distal ends of the left humerus
Humerus
The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....
, the proximal end of the right radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...
, the left carpometacarpus
Carpometacarpus
The carpometacarpus is the fusion of the carpal and metacarpal bone, essentially a single fused bone between the wrist and the knuckles. It is a smallish bone in most birds, generally flattened and with a large hole in the middle. In flightless birds, however, its shape may be slightly different,...
(missing one metacarpal), the left femur
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
(lacking the distal end), the right tibiotarsus (lacking part of the proximal articular surface), and the proximal fragment and worn distal portion of the left tibiotarsus.
Olson and Máiz López examined the bones and showed that they differed from Amazon parrot bones. The tibiotarsus has a narrower internal condyle (the round prominences at the end of a bone) and a distinctive inner cnemial crest
Cnemial crest
The cnemial crest is a crestlike prominence located at the front side of the head of the tibiotarsus or tibia in the legs of running species, many mammals, birds, some reptiles, and dinosaurs. The main extensor muscle of the thigh is attached to this ridge....
(a ridge at the front side of the head) that is more pointed and extends further proximally. The carpometacarpus is proportionally much longer with a process
Process (anatomy)
In anatomy, a process is a projection or outgrowth of tissue from a larger body. The vertebra has several kinds of processes,such as: transverse process, prezygapophysis, postzygapophysis.-Examples:Examples of processes include:...
on the alular metacarpal
Alula
The alula, or bastard wing, is a small projection on the anterior edge of the wing of modern birds. The alula is the freely moving first digit, a bird's "thumb," and is typically covered with three to five small feathers, with the exact number depending on the species...
that is not curved proximally. The femur has a proportionally larger head while the ectepicondylar process
Process (anatomy)
In anatomy, a process is a projection or outgrowth of tissue from a larger body. The vertebra has several kinds of processes,such as: transverse process, prezygapophysis, postzygapophysis.-Examples:Examples of processes include:...
(a bony elevation) and the attachment of pronator brevis
Pronation
In anatomy, pronation is a rotational movement of the forearm at the radioulnar joint, or of the foot at the subtalar and talocalcaneonavicular joints. For the forearm, when standing in the anatomical position, pronation will move the palm of the hand from an anterior-facing position to a...
(one of the two pronation muscles in the wing) on the humerus are more proximal. The elongated coracoid has a relatively narrow shaft and the ventral lip of the glenoid facet (equivalent to the glenoid fossa
Glenoid cavity
The glenoid cavity is a shallow pyriform, articular surface, which is located on the lateral angle of the scapula. It is directed laterally and forward and articulates with the head of the humerus; it is broader below than above and its vertical diameter is the longest.This cavity forms the...
of mammals) is more protruded.
Olson and Máiz López showed that the Saint Croix Macaw is within the same size range as the Blue-throated Macaw and the Lear's Macaw. The length of the tibiotarsus is shorter than in the Blue-throated Macaw but longer than in the Lear's Macaw, while the lengths of the coracoid, carpometacarpus, and femur are smaller. In addition to the size, they observed that the pectoral attachment on the humerus is less excavated while the capital groove (a groove separating two parts of the head of the humerus) is wider; the head of the femur is more massive and when seen from the posterior side, more excavated under the head, neck, and trochanter
Femur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
. Furthermore, the more robust shaft of the femur sets it specifically apart from the Lear's Macaw while the tibiotarsus is more robust with a flared distal extremity.
Distribution
Bones of the species have been excavated at two islands in the Caribbean, Saint Croix and Puerto Rico. The location at Saint Croix is a pre-ColumbianPre-Columbian
The pre-Columbian era incorporates all period subdivisions in the history and prehistory of the Americas before the appearance of significant European influences on the American continents, spanning the time of the original settlement in the Upper Paleolithic period to European colonization during...
Amerindian village site near the current town of Concordia
Concordia, Saint Croix, United States Virgin Islands
Concordia, Saint Croix is a settlement on the island of Saint Croix in the United States Virgin Islands....
, near the Southwest Cape. The bones from Puerto Rico were excavated from an inland village of the Saladoid
Saladoid
Saladoid culture is a pre-columbian indigenous culture of Venezuela and the Caribbean that flourished from 500 BCE to 545 CE.-Name:They have been given the name of the sites where their unique pottery styles were first recognised. The suffix "oid" has been added in this cultural classification...
Indians that was located at the eastern bank of the Río Bucaná
Río Bucaná
Río Bucaná, is a river in the municipality of Ponce, Puerto Rico. Rio Bucana has its origin in barrio Machuelo Arriba where it forms at an altitude of . It forms from the confluence of Rio Cerrillos and Rio Bayagan. It is also fed by Rio Portugues during its southernly run. Rio Bucana used to run...
, north-east of the current city of Ponce
Ponce, Puerto Rico
Ponce is both a city and a municipality in the southern part of Puerto Rico. The city is the seat of the municipal government.The city of Ponce, the fourth most populated in Puerto Rico, and the most populated outside of the San Juan metropolitan area, is named for Juan Ponce de León y Loayza, the...
. A possible third location is Montserrat, where a nearly complete coracoid was excavated (UF
Florida Museum of Natural History
The Florida Museum of Natural History is the State of Florida's official state-sponsored and chartered natural history museum. Its main facilities are located on the campus of the University of Florida in Gainesville, Florida....
4416). The bone of this specimen is slightly smaller than the bone of the Puerto Rico specimen, and could therefore be within the range of the Cuban Red Macaw (Ara tricolor); it has not been assigned to either species.
Although the species had only been found in St. Croix and Puerto Rico, in both cases it was recovered from Amerindian village sites. Williams and Steadman consider it possible that the species may have been native to St. Croix, but Olson and Máiz López regard this as unlikely, noting that parrots, important to the indigenous people, were likely to have been transported between islands. This makes it difficult to determine the natural geographical origins of the parrots known only from subfossil remains found in the West Indian region.
Extinction
The extinction of birds in the Caribbean occurred during three periods. The first period was linked to the sea-level rise after the end of the last ice age. The second period of extinction is linked to the arrival of the Amerindians, while the third extinction period is linked to the arrival of the Europeans. Although the exact causes of the extinction of the Saint Croix Macaw are unknown, it is likely related to arrival of the humans in the region. The presence of the bones in kitchen middens suggests that the species was hunted for food. The bones found by Máiz López are dated to about 300 CE, which implies that the extinction of the Saint Croix Macaw occurred after that.Archeological context
The species was originally described by Wetmore based on material excavated in 1934 by L. J. Korn from a pre-Columbian Amerindian kitchen middenMidden
A midden, is an old dump for domestic waste which may consist of animal bone, human excrement, botanical material, vermin, shells, sherds, lithics , and other artifacts and ecofacts associated with past human occupation...
(dump for domestic waste) near Concordia, Saint Croix, without specifying the age of the bone.
In 1987, Máiz López found several bones of a single bird at the Hernández Colón archeological site on the eastern bank of the Río Bucaná
Río Bucaná
Río Bucaná, is a river in the municipality of Ponce, Puerto Rico. Rio Bucana has its origin in barrio Machuelo Arriba where it forms at an altitude of . It forms from the confluence of Rio Cerrillos and Rio Bayagan. It is also fed by Rio Portugues during its southernly run. Rio Bucana used to run...
in south central Puerto Rico The archeological side in the semi-arid southern foothills
Foothills
Foothills are geographically defined as gradual increases in elevation at the base of a mountain range. They are a transition zone between plains and low relief hills to the adjacent topographically high mountains.-Examples:...
is a pre-Columbian Saladoid
Saladoid
Saladoid culture is a pre-columbian indigenous culture of Venezuela and the Caribbean that flourished from 500 BCE to 545 CE.-Name:They have been given the name of the sites where their unique pottery styles were first recognised. The suffix "oid" has been added in this cultural classification...
village of approximately 15,000 m2 (3.7 acres) situated on an alluvial terrace. Máiz López found the bones in a kitchen midden in the layer that corresponded with the base and beginning of the Pomarrosa phase, which is stylistically related to the Hacienda Grande ceramic style that lasted globally from about 200 BCE
Common Era
Common Era ,abbreviated as CE, is an alternative designation for the calendar era originally introduced by Dionysius Exiguus in the 6th century, traditionally identified with Anno Domini .Dates before the year 1 CE are indicated by the usage of BCE, short for Before the Common Era Common Era...
to 400 CE
Common Era
Common Era ,abbreviated as CE, is an alternative designation for the calendar era originally introduced by Dionysius Exiguus in the 6th century, traditionally identified with Anno Domini .Dates before the year 1 CE are indicated by the usage of BCE, short for Before the Common Era Common Era...
. Radiocarbon dating
Radiocarbon dating
Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...
of charcoal samples indicate that the Pomarrosa phase started locally around 300 CE.