Madtsoiidae is an extinct
family of mostly
Gondwanan
snakes
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints ...
with a
fossil record
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...
extending from early
Cenomanian (
Upper Cretaceous) to late
Pleistocene strata located in
South America,
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
,
India,
Australia and Southern
Europe. Madtsoiidae include
very primitive snakes, which like extant boas and pythons would likely dispatch their prey by
constriction
Constriction is a method used by various snake species to kill or subdue their prey. Although some species of venomous and mildly venomous snakes do use constriction to subdue their prey, most snakes which use constriction lack venom. The snake i ...
. Genera include ''
Madtsoia'', one of the longest snakes known, at an estimated , and the Australian ''
Wonambi
''Wonambi'' is an extinct genus of madtsoiid snakes that lived in late Neogene to late Quaternary Australia. Species of ''Wonambi'' were constrictor snakes unrelated to Australian pythons.
Description
''Wonambi'' was a fairly large snake, wi ...
'' and ''
Yurlunggur
''Yurlunggur'' is a genus of fossil snake in the extinct family Madtsoiidae. This genus was a part of the extinct megafauna of Australia, and contains the species ''Yurlunggur camfieldensis''.
''Y. camfieldensis'' was a large apex predator t ...
''.
As a grouping of basal forms the composition and even the validity of Madtsoiidae is in a state of flux as new pertinent finds are described, with more recent evidence suggesting that it is
paraphyletic as previously defined.
Although madtsoiids persisted on Australia until the Pleistocene, they largely went extinct elsewhere during the
Eocene. However, some species persisted in South America and India through the
Oligocene.
Description
Madtsoiidae was first classified as a subfamily of
Boidae
The Boidae, commonly known as boas or boids, are a family of nonvenomous snakes primarily found in the Americas, as well as Africa, Europe, Asia, and some Pacific Islands. Boas include some of the world's largest snakes, with the green anaconda ...
, Madtsoiinae, in Hoffstetter (1961). Further study and new finds allowed ranking the group as a distinct family in
Linnaean systems. With the recent use of
cladistics
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 cha ...
to unravel
phylogeny, various analyses have posited Madtsoiidae as a likely clade within
Serpentes
Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints ...
, or possible
paraphyletic stem group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...
outside Serpentes and within a more inclusive
Ophidia
__FORCETOC__
Ophidia (also known as Pan-Serpentes) is a group of squamate reptiles including modern snakes and reptiles more closely related to snakes than to other living groups of lizards.
Ophidia was defined as the "most recent common ancesto ...
.
Madtsoiid snakes ranged in size from less than (estimated total length) to over , and are thought to have been constrictors analogous to modern
python
Python may refer to:
Snakes
* Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia
** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia
* Python (mythology), a mythical serpent
Computing
* Python (pr ...
s and
boas, but with more primitive
jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term ''jaws'' is also broadly applied to the whole of the structures constituting the vault of the mouth and serv ...
structures less highly adapted for swallowing large prey. There are specific anatomical features that diagnose members of this family, such as the presence of hypapophyses only in anterior trunk, that the middle and posterior trunk vertebrae possess a moderately or well-developed haemal keel, except for a few near the cloacal region, often with short laterally paired projections on the posterior part of the keel. Also, all trunk and caudal vertebrae have at least a parazygantral foramen, sometimes several of them, located in a more or less distinct fossa that is lateral to each zygantral facet. Additional features are the prezygapophyseal processes' absence while the paracotylar foramina are present and that the diapophyses are relatively wide, exceeding width across prezygapophyses at least in the posterior trunk vertebrae. (Scanlon 2005)
Like most fossil snakes the majority of madtsoiids are known only from isolated
vertebra
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic ...
e, but several (''Madtsoia bai'', ''M. camposi'', ''Wonambi naracoortensis'', ''Nanowana'' spp., unnamed ''Yurlunggur'' spp., ''Najash rionegrina'') have associated or articulated parts of skeletons. Of the genera listed below, all have been referred to Madtsoiidae in all recent classifications except ''Najash rionegrina'', which is included here based on diagnostic vertebral characters described by Apesteguía and Zaher (2006). These authors didn't include Najash among madtsoiids because they consider that madtsoiids are a paraphyletic assemblage of basal macrostomatans related to ''Madtsoia bai'' and consequently, not related to the Cretaceous alethinophidians from southern continents.
Rieppel ''et al.'' (2002) classified ''
Wonambi naracoortensis
''Wonambi'' is an extinct genus of madtsoiid snakes that lived in late Neogene to late Quaternary Australia. Species of ''Wonambi'' were constrictor snakes unrelated to Australian pythons.
Description
''Wonambi'' was a fairly large snake, wi ...
'' within the extant radiation, (
crown group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...
), of snakes as
Macrostomata ''incertae sedis'', but many of their character state attributions for this species have been criticised or refuted by Scanlon (2005) and the better-preserved
skulls of ''Yurlunggur'' sp./spp. have numerous characters apparently more
plesiomorphic
In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades.
Plesiomorphy, symplesiomorphy, apomorphy, and ...
than any macrostomatans (Scanlon, 2006). The partial skull attributed to ''Najash rionegrina'' (Apesteguía and Zaher 2006) resembles that of the non-madtsoiid ''
Dinilysia
''Dinilysia'' (meaning "terrible ilysia") is an extinct genus of snake from the Late Cretaceous ( Coniacian) of South America. ''Dinilysia'' was a relatively large ambush predator, measuring approximately long. The skull morphology of ''Dinily ...
patagonica'', and vertebrae support that they are related. The type material of ''Najash'' is the only possible madtsoiid specimen retaining evidence of pelvic and hindlimb elements, which are claimed to be more plesiomorphic than other Cretaceous limbed snakes, such as ''
Pachyrhachis
''Pachyrhachis'' (from el, παχύς , 'thick' and el, ῥάχῐς , 'spine') is an extinct genus of snake with well developed hind legs known from fossils discovered in Ein Yabrud, near Ramallah, in the central West Bank. It is a relatively ...
'', ''
Haasiophis
''Haasiophis'', consisting of the sole species ''Haasiophis terrasanctus'', is an extinct genus of snakes with hind limbs. It is one of three genera of Cenomanian snakes known to have possessed hindlimbs.
Etymology
The genus was named in honor ...
'' or ''
Eupodophis
''Eupodophis'' is an extinct genus of snake from the Late Cretaceous period. It has two small hind legs and is considered a transitional form between Cretaceous lizards and limbless snakes. The feature, described as vestigial, was most likely u ...
'', in retaining a sacro-iliac contact and well-developed limbs, with a huge and well-defined trochanter. The sacro iliac contact is perhaps misleadingly described by Apesteguía and Zaher as unique possession of a
sacrum, whereas it has rarely been questioned that the
cloaca
In animal anatomy, a cloaca ( ), plural cloacae ( or ), is the posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles and birds, an ...
l vertebrae in snakes are
homologous to the sacrals of limbed
squamate
Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest order of reptiles, comprising lizards, snakes, and amphisbaenians (worm lizards), which are collectively known as squamates or scaled reptiles. With over 10,900 species, i ...
s (i.e. the sacrum is present but has lost contact with the reduced ilia in other taxa). It would be unsurprising if other madtsoiids also possessed hindlimbs as complete as those of ''Najash''.
Several madtsoiid genera have been named using indigenous words for legendary
Rainbow Serpents or
dragons, including ''Wonambi'' (
Pitjantjatjara
The Pitjantjatjara (; or ) are an Aboriginal people of the Central Australian desert near Uluru. They are closely related to the Yankunytjatjara and Ngaanyatjarra and their languages are, to a large extent, mutually intelligible (all are vari ...
), ''Yurlunggur'' (
Yolngu) and ''Nanowana'' (
Ancient Greek ''nano''-, 'dwarf' +
Warlpiri ''Wana'') in Australia, and ''Herensugea'' (
Basque
Basque may refer to:
* Basques, an ethnic group of Spain and France
* Basque language, their language
Places
* Basque Country (greater region), the homeland of the Basque people with parts in both Spain and France
* Basque Country (autonomous co ...
) in Europe. G.G. Simpson (1933) apparently started this trend by compounding ''Madtsoia'' from indigenous roots. In this particular case these originated from the
Tehuelche language
Tehuelche (''Aoniken, Inaquen, Gunua-Kena, Gununa-Kena'') is one of the Chonan languages of Patagonia. Its speakers were nomadic hunters who occupied territory in present-day Chile, north of Tierra del Fuego and south of the Mapuche people. It i ...
, although the reference made was geographic rather than mythological, the derivation being from that language's terms ''mad'', "valley" and ''tsoi'', "cow" as a rough translation from
Spanish
Spanish might refer to:
* Items from or related to Spain:
**Spaniards are a nation and ethnic group indigenous to Spain
**Spanish language, spoken in Spain and many Latin American countries
**Spanish cuisine
Other places
* Spanish, Ontario, Can ...
name of the type locality, Cañadón Vaca.
A 2022 morphological study found Madtsoiidae to be
paraphyletic, with ''
Sanajeh
''Sanajeh'' (meaning "ancient gape" in Sanskrit) is a genus of late Cretaceous madtsoiid snake from western India. A fossil described in 2010 from the Lameta Formation was found coiled around an egg and an adjacent skeleton of a 50 cm (19 i ...
'' being found to be the most
basal member of the
Ophidia
__FORCETOC__
Ophidia (also known as Pan-Serpentes) is a group of squamate reptiles including modern snakes and reptiles more closely related to snakes than to other living groups of lizards.
Ophidia was defined as the "most recent common ancesto ...
, whereas the Cenozoic Australian madtsoiids were basal
alethinophidians.
Classification
* ''
Gigantophis
''Gigantophis'' is an extinct genus represented by its sole member ''Gigantophis garstini'', a giant snake. Before the Paleocene constrictor genus '' Titanoboa'' was described from Colombia in 2009, ''Gigantophis garstini'' was regarded as the l ...
'' Andrews, 1901
** ''Gigantophis garstini'' Andrews, 1901 (Andrews, 1906; Hoffstetter, 1961b;
Paleogene, Late
Eocene;
Egypt (
Birket Qarun
Lake Moeris ( grc, Μοῖρις, genitive Μοίριδος) is an ancient lake in the northwest of the Faiyum Oasis, southwest of Cairo, Egypt. In prehistory, it was a freshwater lake, with an area estimated to vary between and .
It persists ...
and
Qasr el-Sagha Formations),
Libya)
* ''
Madtsoia'' Simpson, 1933
** ''Madtsoia bai'' Simpson, 1933 (Paleogene, Early Eocene
Sarmiento Formation
The Sarmiento Formation ( Spanish: ''Formación Sarmiento''), in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million years from the mid ...
;
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
)
** ''Madtsoia'' cf. ''M. bai'' (Simpson, 1935; Hoffstetter, 1960; Paleogene, Late
Paleocene Las Flores Formation; Argentina)
** ''Madtsoia madagascariensis'' Hoffstetter, 1961a (Piveteau, 1933;
Cretaceous,
Maastrichtian Maevarano Formation
The Maevarano Formation is a Late Cretaceous sedimentary rock formation found in the Mahajanga Province of northwestern Madagascar. It is most likely Maastrichtian in age, and records a seasonal, semiarid environment with rivers that had greatly ...
;
Madagascar)
** ''Madtsoia'' aff. ''madagascariensis'' (de Broin ''et al.'', 1974; Cretaceous,
Coniacian
The Coniacian is an age or stage in the geologic timescale. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series and spans the time between 89.8 ± 1 Ma and 86.3 ± 0.7 Ma (million years ago). The Coniacian is preceded by t ...
or Santonian
In Beceten Formation,
Niger)
** ''Madtsoia camposi'' Rage, 1998 (Paleogene, middle Paleocene
Itaboraí Formation
The Itaboraí Formation ( pt, Formação Itaboraí) is a highly fossiliferous geologic formation and LagerstätteKellner & Campos, 1999, p.399 of the Itaboraí Basin in Rio de Janeiro, southeastern Brazil. The formation reaching a thickness of ...
;
Brazil)
** ''Madtsoia pisdurensis'' Mohabey ''et al'', 2011 (
Cretaceous,
Maastrichtian Lameta Formation
The Lameta Formation, also known as the Infratrappean Beds, is a sedimentary geological formation found in Madhya Pradesh, Gujarat, and Maharashtra, India, associated with the Deccan Traps. It is of Maastrichtian age (Late Cretaceous), and is nota ...
;
India)
* ''
Wonambi
''Wonambi'' is an extinct genus of madtsoiid snakes that lived in late Neogene to late Quaternary Australia. Species of ''Wonambi'' were constrictor snakes unrelated to Australian pythons.
Description
''Wonambi'' was a fairly large snake, wi ...
'' Smith, 1976
** ''Wonambi naracoortensis'' Smith, 1976 (Scanlon and Lee, 2000; Scanlon, 2005; Neogene,
Pliocene to Pleistocene; Australia)
** ''Wonambi barriei'' Scanlon in Scanlon and Lee, 2000 (
Neogene, early
Miocene; Australia)
* ''
Patagoniophis'' Albino, 1986
** ''Patagoniophis parvus'' Albino, 1986 (Cretaceous, Campanian or Maastrichtian
Los Alamitos Formation
The Los Alamitos Formation is a geological formation of the North Patagonian Massif in Rio Negro Province, northwestern Patagonia, Argentina, whose strata date back to the Late Cretaceous ( Late Campanian to Maastrichtian). Dinosaur remains are ...
; Argentina)
** ''Patagoniophis australiensis'' Scanlon, 2005 (Scanlon, 1993; Paleogene, early Eocene; Australia)
* ''
Alamitophis'' Albino, 1986
** ''Alamitophis argentinus'' Albino, 1986 (Cretaceous, Campanian or Maastrichtian
Los Alamitos and
La Colonia Formation
The La Colonia Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al., 2004, pp.600-604
Originally thou ...
s; Argentina)
** ''Alamitophis elongatus'' Albino, 1994 (Cretaceous, Campanian or Maastrichtian
Allen Formation
The Allen Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous (middle Campanian to early Maastrichtian.Salgado et al., 2007 Dinosaur remains are among the fossils that have been recovered from the format ...
; Argentina)
** ''Alamitophis tingamarra'' Scanlon, 2005 (Scanlon, 1993; Paleogene, early Eocene; Australia)
* ''
Rionegrophis'' Albino, 1986
** ''Rionegrophis madtsoioides'' Albino, 1986 (Cretaceous, Campanian or Maastrichtian
Los Alamitos Formation
The Los Alamitos Formation is a geological formation of the North Patagonian Massif in Rio Negro Province, northwestern Patagonia, Argentina, whose strata date back to the Late Cretaceous ( Late Campanian to Maastrichtian). Dinosaur remains are ...
; Argentina)
* ''
Yurlunggur
''Yurlunggur'' is a genus of fossil snake in the extinct family Madtsoiidae. This genus was a part of the extinct megafauna of Australia, and contains the species ''Yurlunggur camfieldensis''.
''Y. camfieldensis'' was a large apex predator t ...
'' Scanlon, 1992
** ''Yurlunggur camfieldensis'' Scanlon, 1992 (Neogene, middle Miocene
Bullock Creek (Northern Territory)
The Bullock Creek Fossil site is one of three known vertebrate fossil sites in the Northern Territory of Australia, along with the Alcoota Fossil Beds and the Kangaroo Well site on Deep Well Station. It is located about south-southeast of Da ...
; Australia)
** ''Yurlunggur'' spp. (Scanlon, 2004; 2006; Paleogene-Neogene,
Oligocene to Miocene; Australia)
* ''
Herensugea'' Rage, 1996
** ''Herensugea caristiorum'' Rage, 1996 (Cretaceous, Campanian or Maastrichtian
Vitoria Formation;
Spain)
* ''
Nanowana'' Scanlon, 1997
** ''Nanowana godthelpi'' Scanlon, 1997 (Neogene, early-to-middle Miocene
Australian Fossil Mammal Sites (Riversleigh)
Riversleigh World Heritage Area is Australia's most famous fossil location, recognised for the series of well preserved fossils deposited from the Late Oligocene to more recent geological periods. The fossiliferous limestone system is located ne ...
; Australia)
** ''Nanowana schrenki'' Scanlon, 1997 (Neogene, early-to-middle Miocene; Australia)
* ''
Sanajeh
''Sanajeh'' (meaning "ancient gape" in Sanskrit) is a genus of late Cretaceous madtsoiid snake from western India. A fossil described in 2010 from the Lameta Formation was found coiled around an egg and an adjacent skeleton of a 50 cm (19 i ...
'' Wilson ''et al.'', 2010
** ''Sanajeh indicus'' Wilson ''et al.'', 2010 (Cretaceous, Maastrichtian
Lameta Formation
The Lameta Formation, also known as the Infratrappean Beds, is a sedimentary geological formation found in Madhya Pradesh, Gujarat, and Maharashtra, India, associated with the Deccan Traps. It is of Maastrichtian age (Late Cretaceous), and is nota ...
; India)
* ''
Menarana'' Laduke ''et al.'', 2010
** ''Menarana nosymena'' Laduke ''et al.'', 2010 (Late Cretaceous, Maastrichtian
Maevarano Formation
The Maevarano Formation is a Late Cretaceous sedimentary rock formation found in the Mahajanga Province of northwestern Madagascar. It is most likely Maastrichtian in age, and records a seasonal, semiarid environment with rivers that had greatly ...
; Madagascar)
** ''Menarana laurasiae'' Rage, 1996 (Astibia ''et al.'', 1990; Cretaceous, Campanian or
Maastrichtian; Spain)
* ''
Nidophis'' Vasile ''et al.'', 2013
** ''Nidophis insularis'' Vasile ''et al.'', 2013 (Late Cretaceous, Maastrichtian
Densus-Ciula Formation; Romania)
*''
Adinophis'' Pritchard ''et al.'', 2014
**''Adinophis fisaka'' Pritchard ''et al.,'' 2014 (Late Cretaceous, Maastrichtian
Maevarano Formation
The Maevarano Formation is a Late Cretaceous sedimentary rock formation found in the Mahajanga Province of northwestern Madagascar. It is most likely Maastrichtian in age, and records a seasonal, semiarid environment with rivers that had greatly ...
; Madagascar)
*''
Platyspondylophis'' Smith ''et al.'', 2016
**''Platyspondylophis tadkeshwarensis'' Smith ''et al.'', 2016 (Paleogene, Eocene
Cambay Shale; India)
*''
Eomadtsoia'' Gómez ''et al.,'' 2019
**''Eomadtsoia ragei'' Gómez ''et al.'', 2019 (Cretaceous, Maastrichtian
La Colonia Formation
The La Colonia Formation is a geological formation in Argentina whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel et al., 2004, pp.600-604
Originally thou ...
; Argentina)
*''
Powellophis'' Garberoglio ''et al.'', 2022
** ''Powellophis andina'' Garberoglio ''et al.,'' 2022 (Paleogene, Paleocene
Mealla Formation
The Mealla Formation is a geological formation of the Santa Bárbara Subgroup, part of the Salta Group in the Salta Basin in northwestern Argentina whose strata date back to the Middle to Late Paleocene of the Paleogene.
Description
The Me ...
; Argentina)
Unnamed specimens
* Madtsoiidae indet. (Rage, 1987; Paleogene, Paleocene;
Morocco)
* Madtsoiidae indet. (Werner and Rage, 1994, Rage and Werner 1999; Cretaceous,
Cenomanian;
Sudan)
*?Madtsoiid (Rage and Prasad, 1992; Cretaceous, Maastrichtian; India)
*?Madtsoiid (Rage, 1991; Paleogene, early Paleocene
Santa Lucía Formation
The Santa Lucía Formation is a Maastrichtian to Paleocene (Danian) geologic formation in Bolivia. Fossil ornithopod tracks have been reported from the Cretaceous lower part of the formation.Weishampel, et al., 2004, pp.517-607 It is the type for ...
; Bolivia)
*?Madtsoiidae indet. cf. ''Madtsoia'' sp. (Scanlon, 2005; Paleogene, early Eocene; Australia)
* Madtsoiidae indet. (Folie and Codrea, 2005; Cretaceous, Maastrichtian;
Romania)
* Madtsoiidae nov. (Gomez and Baez, 2006; Cretaceous, late Campanian or early Maastrichtian; Argentina)
* Madtsoiidae indet. (Wazir et al., 2022; Late-Oligocene, India)
[Wasim Abass Wazir, Ramesh Kumar Sehgal, Andrej Čerňanský, Rajeev
Patnaik, Navin Kumar, Abhishek Pratap Singh, Piyush Uniyal & Ningthoujam Premjit Singh
(2022): A find from the Ladakh Himalaya reveals a survival of madtsoiid snakes (Serpentes,
Madtsoiidae) in India through the late Oligocene, Journal of Vertebrate Paleontology, https://doi.org/10.1080/02724634.2021.2058401
]
Phylogeny
According to a cladistic analysis by Scanlon (2006), ''Wonambi'' and ''Yurlunggur'' as representative genera of Madtsoiidae form a
monophyletic assembly. However, as '' Madtsoia'' is not included, its grouping in the same family is questionable.
References
Bibliography and further reading
* Albino, A.M. 1986. Nuevos Boidae Madtsoiinae en el Cretacico tardio de Patagonia (Formacion Los Alamitos, Rio Negro, Argentina). pp. 15–21 in J.F. Bonaparte (ed.), Simposio Evolucion de los Vertebrados Mesozoicos. Actas IV Congreso Argentino de Paleontología y Bioestratigrafía, Mendoza.
*
*
* Andrews, C.W. 1906. A descriptive catalogue of the Tertiary Vertebrata of the Fayum, Egypt. British Museum (Natural History), London.
*
*
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*
*Gomez, R.O. and A.M. Baez. 2006. A new madtsoiid snake (Squamata, Ophidia) from the Upper Cretaceous of Patagonia. XXII Jornadas Argentinas de Paleontología de Vertebrados, San Juan, Argentina (2006): 21.
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{{Taxonbar, from=Q622892
Prehistoric reptile families
Cretaceous snakes
Cenomanian first appearances
Pleistocene extinctions
Cretaceous–Paleogene boundary
Taxa named by Robert Hoffstetter