''Triaenops goodmani'' is an extinct bat from

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

in the genus ''

Triaenops ''Triaenops'' is a genus of bat in the family Hipposideridae. It is classified in the tribe Triaenopini, along with the closely related genus '' Paratriaenops'' and perhaps the poorly known '' Cloeotis''. The species of ''Paratriaenops'', which ...

''. It is known from three lower jaws collected in a cave at Anjohibe in 1996, and described as a new species in 2007. The material is at most 10,000 years old. A bat

humerus The humerus (; ) 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 and ulna, and consists of three sections. The humeral upper extremity consists of a roun ...

(upper arm bone) from the same site could not be identified as either ''T. goodmani'' or the living '' T. menamena''. ''T. goodmani'' is identifiable as a member of ''Triaenops'' or the related genus ''

Paratriaenops ''Paratriaenops'' is a genus in the bat family Hipposideridae. It is classified in the tribe Triaenopini, along with the closely related genus ''Triaenops'' and perhaps the poorly known '' Cloeotis''. The species of ''Paratriaenops'' were placed ...

'' by a number of features of the teeth, such as the single-cusped, canine-like fourth

premolar The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth ...

and the presence of a gap between the

entoconid Many different terms have been proposed for features of the tooth crown in mammals. The structures within the molars receive different names according to their position and morphology. This nomenclature was developed by Henry Fairfield Osborn i ...

and hypoconulid cusps on the first two

molars The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone to ...

. ''T. goodmani'' is larger than the living species of ''Triaenops'' and ''Paratriaenops'' on Madagascar, and on the first molar the

protoconid Many different terms have been proposed for features of the tooth crown in mammals. The structures within the molars receive different names according to their position and morphology. This nomenclature was developed by Henry Fairfield Osborn i ...

cusp is only slightly higher than the

hypoconid Many different terms have been proposed for features of the tooth crown in mammals. The structures within the molars receive different names according to their position and morphology. This nomenclature was developed by Henry Fairfield Osborn ...

, not much higher as in the other species.

Taxonomy and distribution

In 1996, a team led by David Burney collected

breccia Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of di ...

s containing remains of bats and other animals from the cave of Anjohibe in northwestern Madagascar. The bats in the sample were described by Karen Samonds (previously Irwin) in her 2006 Ph.D. dissertation and a 2007 paper. She found several living species in addition to two extinct ones that she described as new, ''Triaenops goodmani'' and ''

Hipposideros besaoka ''Hipposideros besaoka'' is an extinct bat from Madagascar in the genus ''Hipposideros''. It is known from numerous jaws and teeth, which were collected in a cave at Anjohibe in 1996 and described as a new species in 2007. The site where ''H.&nbs ...

''. At the time, the genus ''

'' was thought to include three species on Madagascar–''Triaenops auritus'', ''Triaenops furculus'', and ''Triaenops rufus''.Samonds, 2007, p. 46 Since then, Steven Goodman and Julie Ranivo have discovered that the name ''rufus'' is not in fact applicable to the Madagascar species and proposed the name ''

Triaenops menamena ''Triaenops menamena'' is a bat in the genus ''Triaenops'' found on Madagascar, mainly in the drier regions. It was known as ''Triaenops rufus'' until 2009, when it was discovered that that name had been incorrectly applied to the species. ''Triae ...

'' for the Madagascan bats previously known as ''Triaenops rufus''. In addition, Petr Benda and Peter Vallo have removed the other two Madagascan species to a separate genus ''

'', so that they are now known as ''

Paratriaenops auritus Grandidier's trident bat (''Paratriaenops auritus'') is a species of bat in the family Hipposideridae endemic to Madagascar. It was formerly assigned to the genus ''Triaenops'', but is now placed in the separate genus ''Paratriaenops''. Taxonomy ...

'' and ''

Paratriaenops furculus ''Paratriaenops furculus'', also known as Trouessart's trident bat, is a species of bat in the family Hipposideridae. It is endemic to Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan' ...

''. 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 ...

of the

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 ...

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 ...

, ''goodmani'', honors Steven Goodman for his research on Madagascan bats. The material of ''T. goodmani'' is from locality OLD SE within the cave and is about 10,000 years old or younger. A

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...

analysis using morphological data could not resolve the relationships of ''Triaenops goodmani'', but did not place it with the other species of ''Triaenops'' and ''Paratriaenops'' studied. In a 2008 paper, Amy Russell and colleagues commented that cranial (skull) characteristics of ''T. goodmani'' suggest it is a member of the "''T. furculus/T. auritus'' group", now placed in ''Paratriaenops''.

Description

''Triaenops goodmani'' is known from three

mandible 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 tooth, teeth in place. The mandible sits beneath the maxilla. It is the only movabl ...

s (lower jaws): one with the fourth premolar (p4) and first and second molars (m1–2) and two with the second and third molars (m2–3). The jaw is relatively robust. The p4 resembles a canine, having a single cusp that is about as high as the highest cusp on m1 and lacking accessory shelves or cusps. The molars are narrow-crowned and longer than in ''T. menamena'', ''P. auritus'', and ''P. furculus''. Length of m2 ranges from 1.55 to 1.57 mm and width from 0.98 to 1.02 mm. On m1, the

trigonid The molars or molar teeth are large, flat tooth, teeth at the back of the mouth. They are more developed in mammal, mammals. They are used primarily to comminution, grind food during mastication, chewing. The name ''molar'' derives from Latin, ...

(front group of cusps) is narrower and slightly higher than the

talonid The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone to ...

at the back. The

, one of the main cusps in the trigonid, is the highest cusp,Samonds, 2007, p. 47 but is only slightly higher than the

(a cusp in the talonid); in living Madagascan ''Triaenops'' and ''Paratriaenops'', the protoconid is substantially higher than the hypoconid. The paraconid,

metaconid Many different terms have been proposed for features of the tooth crown in mammals. The structures within the molars receive different names according to their position and morphology. This nomenclature was developed by Henry Fairfield Osborn ...

(both cusps in the trigonid), and

(a cusp in the talonid) are lower than in ''Paratriaenops auritus''. The hypoconulid (part of the talonid) is small but distinct and is the lowest cusp. It is separated from the entoconid by a gap. ''T. goodmani'' lacks a ridge, the preentocristid, connecting the entoconid to the metaconid. There is a crest ( cingulum) at the front and back of the tooth. The last two molars are similar to m1, but in m2 the talonid is only slightly wider than the trigonid and in m3 the two are of equal width. In addition, a shelf is present between the protoconid and hypoconid on m2 and m3 is smaller, lacks the gap between the entoconid and hypoconulid, and has a weak ridge between the entoconid and metaconid. These characteristics are typical of ''Triaenops'' and ''Paratriaenops''.Samonds, 2007, p. 48 From the same site where ''T. goodmani'' was found, Samonds also recorded the distal (far) end of a ''Triaenops''

(upper arm bone), with a width of 3.58 mm. This bone was similar to humeri of ''T. menamena'', but she did not identify it as either species because of the small size difference between ''T. menamena'' and ''T. goodmani''.Samonds, 2007, p. 49 In site NCC-1 (estimated 69,600 to 86,800 years old),Samonds, 2007, p. 43 two ''Triaenops'' mandibles were recorded, one with p4 and m1 and another with m1–2 and part of m3.Samonds, 2007, p. 55 Relative to living ''Triaenops'' and ''Paratriaenops'', m1 in those jaws is longer and narrower. Although sample sizes are small, the measurements do not resemble those of ''T. goodmani''. In addition, the ridge between the entoconid and metaconid is stronger than in ''T. goodmani''. Samonds identified these jaws only as ''Triaenops''.Samonds, 2007, p. 57

References

Literature cited

*Benda, P. and Vallo, P. 2009. Taxonomic revision of the genus ''Triaenops'' (Chiroptera: Hipposideridae) with description of a new species from southern Arabia and definitions of a new genus and tribe. Folia Zoologica 58(Monograph 1):1–45. *Goodman, S.M. and Ranivo, J. 2009
The geographical origin of the type specimens of ''Triaenops rufus'' and ''T. humbloti'' (Chiroptera: Hipposideridae) reputed to be from Madagascar and the description of a replacement species name
(subscription required). Mammalia 73:47–55. *Russell, A.L., Goodman, S.M. and Cox, M.P. 2008
Coalescent analyses support multiple mainland-to-island dispersals in the evolution of Malagasy ''Triaenops'' bats (Chiroptera: Hipposideridae)
Journal of Biogeography 35:995–1003. *Samonds (Irwin), K.E. 2006. The origin and evolution of Malagasy bats: Implications of new Late Pleistocene fossils and cladistic analyses for reconstructing biogeographic history. Ph.D. Dissertation, Department of Anatomical Sciences, Stony Brook University, xx + 403 pp. *Samonds, K.E. 2007
Late Pleistocene bat fossils from Anjohibe Cave, northwestern Madagascar
Acta Chiropterologica 9(1):39–65. {{Good article Extinct mammals Triaenops Holocene extinctions