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🇧🇷 Espécie Brasileira
Aratasaurus museunacionali
Cretaceous Carnivore

Aratasaurus

Aratasaurus museunacionali

"Fire-born lizard (Museu Nacional)"

Period
Cretaceous · Albiano
Lived
113–108 Ma
Length
up to 3.12 m
Estimated weight
34 kg
Country of origin
Brasil
Described in
2020 by Juliana M. Sayão, Antônio Á.F. Saraiva, Arthur S. Brum, Renan A.M. Bantim, Rafael C.L.P. Andrade, Xin Cheng, Flaviana J. Lima, Helder P. Silva e Alexander W.A. Kellner

About this species

Aratasaurus museunacionali is a small basal coelurosaurian theropod from the Early Cretaceous (Albian, ~110 Ma) Romualdo Formation in the Araripe Basin, Santana do Cariri (Ceará, Brazil). Described by Juliana Sayão and colleagues in 2020, holotype MPSC R 2089 consists of an articulated right hindlimb (distal femur, proximal tibia, partial metatarsals, several phalanges and three unguals) of a juvenile individual aged around 4 years, estimated at 3.12 metres long and 34 kg. The name means 'lizard born from fire', referring to the fire at the Museu Nacional of Rio de Janeiro in September 2018, just before publication. Aratasaurus expands the known diversity of small theropods from the Araripe Basin, alongside Santanaraptor, Mirischia, Irritator and Angaturama, and is a rare basal coelurosaur from Gondwana.

Geological formation & environment

Romualdo Formation (formerly the 'Romualdo Member' of the Santana Formation), part of the Santana Group, Araripe Basin. Albian age (~110 Ma, base dated at 110.5 ± 7.4 Ma from fish teeth). Lithology dominated by mudstones, shales and calcareous concretions with exceptional three-dimensional preservation of vertebrates and invertebrates. World-class Konservat-Lagerstätte. The fauna includes theropods (Aratasaurus, Santanaraptor, Mirischia, Irritator, Angaturama), pterosaurs (Anhanguera, Tropeognathus, Tapejara, Thalassodromeus, Tupuxuara), around 25 fish species (Dastilbe, Vinctifer, Rhacolepis, Cladocyclus, Mawsonia), plus turtles, crocodyliforms and preserved vegetation. Aratasaurus comes specifically from the base of the formation, at a stratigraphic level about 2.5 metres above the contact with the Ipubi Formation.

Image gallery

Ecology and behavior

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Habitat

Semi-arid coastal plain around a shallow epicontinental sea in the interior of northeastern Brazil during the Albian (~110 Ma). The Romualdo Formation represents the transgressive phase of a rift basin, with hypersaline lagoons and calcareous concretions where exceptional fossil preservation occurred. Vegetation consisted of drought-tolerant conifers, cycads and gnetophytes, with wetter pulses during the transgression.

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Feeding

Small carnivorous theropod with teeth and claws adapted to predation. As a juvenile, it probably fed on small vertebrates (lizards, mammaliaforms, stranded fish) and invertebrates. In adults, the diet would likely have included larger prey or carcasses. Its small size made it possible prey for the large spinosaurids (Irritator, Angaturama) of the same ecosystem.

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Behavior and senses

Osteohistology indicates rapid growth typical of coelurosaurs, interrupted by death at ~4 years. There is no direct evidence of integument or social behaviour, but by analogy with other basal coelurosaurs Aratasaurus probably had feathers or protofeathers, was an active thermoregulator and led a cursorial lifestyle on the semi-open terrain of the Araripe.

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Physiology and growth

The juvenile holotype allows one of the few detailed histological analyses of a Gondwanan coelurosaur, showing rapid growth and elevated metabolism consistent with the current picture of active endothermic small theropods. The long bones show successive lines of arrested growth, consistent with seasonal variation on the Araripe coastal plain.

Paleogeography

Continental configuration

Mapa paleogeográfico do Cretáceous (~90 Ma)

Ron Blakey · CC BY 3.0 · Cretáceous, ~90 Ma

During the Albiano (~113–108 Ma), Aratasaurus museunacionali inhabited Laramidia, the western half of present-day North America, separated from the east by the Western Interior Seaway, a shallow sea dividing the continent. The continents were in very different positions: India was drifting toward Asia, Antarctica was still connected to Australia, and South America was an isolated island.

Bone Inventory

Estimated completeness 10%

The holotype preserves only the articulated right hindlimb: distal femur, proximal tibia, partial metatarsals, several pedal phalanges and three pedal unguals. Despite low completeness, the articulation of the material and the presence of diagnostic features on the femur, tibia and metatarsals allowed assignment to a new genus of basal coelurosaur. Bone histology showed the specimen to be juvenile (~4 years old).

Found (6)
Inferred (9)
Esqueleto de dinossauro — theropod
Sayão et al. 2020 (Wikimedia Commons) CC BY 4.0

Found elements

extremidade distal do fêmur direitoextremidade proximal da tíbia direitametatarsais I–IV parciaisvárias falanges do pétrês garras pedais (unguais)membro posterior direito articulado

Inferred elements

crâniomandíbulapescoço e troncocintura escapularmembros anterioresmaioria do esqueleto axialpelvetíbia e fíbula completaspé esquerdo

Scientific Literature

15 papers in chronological order — from the original description to recent research.

2020

The first theropod dinosaur (Coelurosauria, Theropoda) from the base of the Romualdo Formation (Albian), Araripe Basin, Northeast Brazil

Sayão, J.M., Saraiva, A.Á.F., Brum, A.S., Bantim, R.A.M., Andrade, R.C.L.P., Cheng, X., Lima, F.J., Silva, H.P. e Kellner, A.W.A. · Scientific Reports

Original description of Aratasaurus museunacionali, the first coelurosaur reported from the base of the Romualdo Formation in the Araripe Basin. The material is an articulated right hindlimb, assigned to a juvenile aged around 4 years according to osteohistological analysis. Compares the fossil with Zuolong salleei (China) and with other Brazilian coelurosaurs and proposes a close systematic relationship with basal Gondwanan coelurosaurs.

Figure 10 of the paper: life reconstruction of Aratasaurus museunacionali by Maurilio Oliveira, showing the small juvenile coelurosaur in the Albian coastal landscape of the Araripe.

Figure 10 of the paper: life reconstruction of Aratasaurus museunacionali by Maurilio Oliveira, showing the small juvenile coelurosaur in the Albian coastal landscape of the Araripe.

Figure 7 of the paper: osteohistological analysis of the femur and tibia, the basis for concluding that holotype MPSC R 2089 is a juvenile aged about 4 years and still growing.

Figure 7 of the paper: osteohistological analysis of the femur and tibia, the basis for concluding that holotype MPSC R 2089 is a juvenile aged about 4 years and still growing.

Figure 1

Figure 1

Figure 2

Figure 2

Figure 3

Figure 3

Figure 4

Figure 4

1999

Short note on a new dinosaur (Theropoda, Coelurosauria) from the Santana Formation (Romualdo Member, Albian), northeastern Brazil

Kellner, A.W.A. · Boletim do Museu Nacional, Nova Série, Geologia

Original description of Santanaraptor placidus, the first coelurosaur reported from the Araripe Basin, based on a partial skeleton with preserved soft tissue (MN 4802-V). A central reference for the systematics and paleobiogeography of basal Brazilian coelurosaurs, later contextualising the description of Aratasaurus.

Santanaraptor placidus, the basal coelurosaur from the Romualdo Formation originally described by Kellner in 1999 based on holotype MN 4802-V, which preserves soft tissues.

Santanaraptor placidus, the basal coelurosaur from the Romualdo Formation originally described by Kellner in 1999 based on holotype MN 4802-V, which preserves soft tissues.

Life reconstruction of Santanaraptor, the first coelurosaur reported from the Araripe Basin and a direct comparison reference for the later description of Aratasaurus.

Life reconstruction of Santanaraptor, the first coelurosaur reported from the Araripe Basin and a direct comparison reference for the later description of Aratasaurus.

1996

First Early Cretaceous dinosaur from Brazil with comments on Spinosauridae

Kellner, A.W.A. e Campos, D.A. · Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen

Describes Angaturama limai, a large spinosaurid from the Romualdo Formation, establishing the oldest record of Brazilian Cretaceous dinosaurs. Provides the faunal framework in which small theropods like Santanaraptor, Mirischia and Aratasaurus would later be described.

Reconstructed skeleton of Angaturama limai, the large spinosaurid from the Romualdo Formation described by Kellner and Campos in 1996 from the front of the skull.

Reconstructed skeleton of Angaturama limai, the large spinosaurid from the Romualdo Formation described by Kellner and Campos in 1996 from the front of the skull.

Comparative life restoration of spinosaurids, the group to which Angaturama belongs. The 1996 paper established the earliest record of Cretaceous dinosaurs in Brazil.

Comparative life restoration of spinosaurids, the group to which Angaturama belongs. The 1996 paper established the earliest record of Cretaceous dinosaurs in Brazil.

2000

Skeletal remains of a small theropod dinosaur with associated soft structures from the Lower Cretaceous Santana Formation of northeastern Brazil

Martill, D.M., Frey, E., Sues, H.-D. e Cruickshank, A.R.I. · Canadian Journal of Earth Sciences

First description of the remains of Mirischia asymmetrica, another small coelurosaur from the Romualdo Formation with associated soft tissues. Establishes, together with Santanaraptor, the diversity of small theropods known in the Araripe Basin before Aratasaurus.

Fossil of the small coelurosaur now known as Mirischia asymmetrica, described in 2000 by Martill and colleagues from a calcareous nodule of the Romualdo Formation, with associated soft tissues.

Fossil of the small coelurosaur now known as Mirischia asymmetrica, described in 2000 by Martill and colleagues from a calcareous nodule of the Romualdo Formation, with associated soft tissues.

Mirischia and Santanaraptor side by side: the two small coelurosaurs from the Romualdo Formation that made up the faunal context for the later description of Aratasaurus.

Mirischia and Santanaraptor side by side: the two small coelurosaurs from the Romualdo Formation that made up the faunal context for the later description of Aratasaurus.

2004

Ecology, systematics and biogeographical relationships of dinosaurs, including a new theropod, from the Santana Formation (?Albian, Early Cretaceous) of Brazil

Naish, D., Martill, D.M. e Frey, E. · Historical Biology

Formal naming of Mirischia asymmetrica and review of the ecology and biogeography of Santana (now Romualdo) Formation dinosaurs. Discusses the pelvic asymmetry of the genus and its systematic position among basal coelurosaurs, direct context for the later description of Aratasaurus.

Holotype of Mirischia asymmetrica. Naish, Martill and Frey (2004) formally named the genus and species, based on the asymmetry between the left and right ischia.

Holotype of Mirischia asymmetrica. Naish, Martill and Frey (2004) formally named the genus and species, based on the asymmetry between the left and right ischia.

Mirischia in a reconstructed paleoenvironmental scene, the Early Cretaceous ecological and biogeographic context of the Araripe discussed by Naish and colleagues in 2004.

Mirischia in a reconstructed paleoenvironmental scene, the Early Cretaceous ecological and biogeographic context of the Araripe discussed by Naish and colleagues in 2004.

2002

Irritator challengeri, a spinosaurid (Dinosauria: Theropoda) from the Lower Cretaceous of Brazil

Sues, H.-D., Frey, E., Martill, D.M. e Scott, D.M. · Journal of Vertebrate Paleontology

Describes Irritator challengeri, a spinosaurid from the Romualdo Formation, based on a well-preserved skull. Provides context for the large theropods of the Araripe ecosystem that shared environments with small coelurosaurs such as Santanaraptor and, later, Aratasaurus.

Holotype of Irritator challengeri, a well-preserved skull from the Romualdo Formation redescribed in detail by Sues and colleagues in 2002, consolidating the genus within Spinosauridae.

Holotype of Irritator challengeri, a well-preserved skull from the Romualdo Formation redescribed in detail by Sues and colleagues in 2002, consolidating the genus within Spinosauridae.

Life reconstruction of Irritator challengeri. The 2002 paper provides the anatomical framework for the large predator that coexisted with small theropods such as Santanaraptor and Aratasaurus.

Life reconstruction of Irritator challengeri. The 2002 paper provides the anatomical framework for the large predator that coexisted with small theropods such as Santanaraptor and Aratasaurus.

1996

A new crested maniraptoran dinosaur from the Santana Formation (Lower Cretaceous) of Brazil

Martill, D.M., Cruickshank, A.R.I., Frey, E., Small, P.G. e Clarke, M. · Journal of the Geological Society

Original description of Irritator challengeri (before Sues et al. 2002 redescribed the species in detail). One of the first descriptions of theropods in the Araripe Basin and a classic reference for the ecosystem where Aratasaurus lived.

Holotype skull of Irritator challengeri, originally described by Martill and colleagues in 1996 as a 'crested maniraptoran' before the revision by Sues et al. 2002.

Holotype skull of Irritator challengeri, originally described by Martill and colleagues in 1996 as a 'crested maniraptoran' before the revision by Sues et al. 2002.

Reconstructions of spinosaurids, the family where Irritator was later placed. The 1996 paper is one of the first descriptions of theropods from the Araripe Basin.

Reconstructions of spinosaurids, the family where Irritator was later placed. The 1996 paper is one of the first descriptions of theropods from the Araripe Basin.

2025

The coelurosaur theropods of the Romualdo Formation, Early Cretaceous (Aptian) of Brazil: Santanaraptor placidus meets Mirischia asymmetrica

Delcourt, R., Grillo, O.N., Hendrickx, C., Kellermann, M. e Langer, M.C. · The Anatomical Record

Joint redescription of the two best-known coelurosaurs from the Romualdo Formation, Santanaraptor placidus and Mirischia asymmetrica. Establishes the most recent anatomical-phylogenetic framework for Brazilian Cretaceous coelurosaurs, essential to reassess the position of Aratasaurus within Coelurosauria.

Santanaraptor placidus, one of the two taxa redescribed by Delcourt and colleagues in 2025 in a joint analysis that updated the phylogenetic position of Brazilian coelurosaurs.

Santanaraptor placidus, one of the two taxa redescribed by Delcourt and colleagues in 2025 in a joint analysis that updated the phylogenetic position of Brazilian coelurosaurs.

Mirischia asymmetrica, the second taxon redescribed in 2025. The study provides the most recent anatomical framework for reassessing the position of Aratasaurus within Coelurosauria.

Mirischia asymmetrica, the second taxon redescribed in 2025. The study provides the most recent anatomical framework for reassessing the position of Aratasaurus within Coelurosauria.

2020

A maned theropod dinosaur from Gondwana with elaborate integumentary structures

Smyth, R.S.H., Martill, D.M., Frey, E., Rivera-Sylva, H.E. e Lenz, N. · Cretaceous Research

Original description of Ubirajara jubatus, a small theropod with elaborate integumentary structures, from the Crato Formation (immediately underlying the Romualdo). The paper was retracted in 2022 (the name is now considered unavailable), but it is relevant for contextualising the debate about small Araripe theropods at the same time as the Aratasaurus description.

Life reconstruction of Ubirajara jubatus, a small theropod from the Crato Formation described in 2020 with elaborate integumentary structures. The paper was retracted in 2022 and the name is now considered unavailable.

Life reconstruction of Ubirajara jubatus, a small theropod from the Crato Formation described in 2020 with elaborate integumentary structures. The paper was retracted in 2022 and the name is now considered unavailable.

Skeletal diagram of Ubirajara jubatus showing the preserved elements. The debate surrounding the specimen provides context for the Aratasaurus description at the same time.

Skeletal diagram of Ubirajara jubatus showing the preserved elements. The debate surrounding the specimen provides context for the Aratasaurus description at the same time.

2021

Paleoenvironmental evolution of the Aptian Romualdo Formation, Araripe Basin, Northeastern Brazil

Varejão, F.G., Warren, L.V., Perinotto, J.A.J., Neumann, V.H., Freitas, B.T., Assine, M.L. e Simões, M.G. · Palaeogeography, Palaeoclimatology, Palaeoecology

Paleoenvironmental review of the Romualdo Formation, with new datings and analysis of the marine transgressions that shaped the Araripe Basin during the Albian. Provides the stratigraphic and paleoecological context in which Aratasaurus was found, near the base of the formation.

Map of the Araripe Basin showing the distribution of the Romualdo Formation and the other members of the Santana Group, the geological setting revised by Varejão and colleagues in 2021.

Map of the Araripe Basin showing the distribution of the Romualdo Formation and the other members of the Santana Group, the geological setting revised by Varejão and colleagues in 2021.

Outcrop of the Romualdo Formation with stratigraphic interpretation, the type of exposure analysed by Varejão and colleagues to reconstruct the Albian paleoenvironment where Aratasaurus lived.

Outcrop of the Romualdo Formation with stratigraphic interpretation, the type of exposure analysed by Varejão and colleagues to reconstruct the Albian paleoenvironment where Aratasaurus lived.

2007

The Crato Fossil Beds of Brazil: Window into an Ancient World

Martill, D.M., Bechly, G. e Loveridge, R.F. (editores) · Cambridge University Press

Reference volume on the paleobiota of the Crato Formation, directly underlying the Romualdo Formation in the Araripe Basin. Provides the geological, paleoenvironmental and systematic context essential to understanding the ecosystem in which Aratasaurus later lived.

Fossilised feathers and the fish Dastilbe, two of the types of exceptional fossils documented in the 2007 book by Martill, Bechly and Loveridge on the Crato Formation paleobiota.

Fossilised feathers and the fish Dastilbe, two of the types of exceptional fossils documented in the 2007 book by Martill, Bechly and Loveridge on the Crato Formation paleobiota.

Cladocyclus, an ichthyodectiform fish from the Crato Formation, illustrates the ichthyological diversity described in detail in the reference volume on the Crato Lagerstätte.

Cladocyclus, an ichthyodectiform fish from the Crato Formation, illustrates the ichthyological diversity described in detail in the reference volume on the Crato Lagerstätte.

2008

Dolomite pipes in the Crato Formation fossil lagerstätte (Lower Cretaceous, Aptian), of northeastern Brazil

Martill, D.M., Loveridge, R.F. e Heimhofer, U. · Cretaceous Research

Sedimentological analysis of the Crato Formation dolomite pipes and their relation to exceptional fossil preservation in the Araripe Basin. Complements understanding of the depositional environment that favoured fossils of Aratasaurus, Santanaraptor and Mirischia.

Outcrop of the Ipubi and Romualdo Formations in the Araripe Basin. The 2008 paper analyses diagenetic features (dolomite pipes) tied to the exceptional preservation in the sedimentary package.

Outcrop of the Ipubi and Romualdo Formations in the Araripe Basin. The 2008 paper analyses diagenetic features (dolomite pipes) tied to the exceptional preservation in the sedimentary package.

Depositional environments and sequence stratigraphy of the Araripe Basin, the framework within which Martill and colleagues place the dolomite pipes they discuss.

Depositional environments and sequence stratigraphy of the Araripe Basin, the framework within which Martill and colleagues place the dolomite pipes they discuss.

2017

The transgressive-regressive cycle of the Romualdo Formation (Araripe Basin): Sedimentary archive of the Early Cretaceous marine ingression in the interior of Northeast Brazil

Custódio, M.A., Quaglio, F., Warren, L.V., Simões, M.G., Fürsich, F.T., Perinotto, J.A.J. e Assine, M.L. · Sedimentary Geology

Reconstruction of the transgressive-regressive cycle of the Romualdo Formation, documenting the entry and exit of the sea into the interior of northeastern Brazil during the Early Cretaceous. Provides the paleogeographic baseline directly applicable to the environment in which Aratasaurus lived.

Lake and sea level cycles in the Crato, Ipubi and Romualdo formations, part of the transgressive-regressive cycle reconstructed by Custódio and colleagues in 2017.

Lake and sea level cycles in the Crato, Ipubi and Romualdo formations, part of the transgressive-regressive cycle reconstructed by Custódio and colleagues in 2017.

Synthesis of the Araripe Basin depositional environments, which record the entry and exit of the sea during the Early Cretaceous. Direct paleogeographic context for the environment in which Aratasaurus lived.

Synthesis of the Araripe Basin depositional environments, which record the entry and exit of the sea during the Early Cretaceous. Direct paleogeographic context for the environment in which Aratasaurus lived.

2011

Mesozoic dinosaurs from Brazil and their biogeographic implications

Bittencourt, J.S. e Langer, M.C. · Anais da Academia Brasileira de Ciências

Comprehensive review of Brazilian Mesozoic dinosaurs and their biogeographic implications for Gondwana. A synthesis of reference for situating Aratasaurus within the set of previously known Brazilian theropods.

Santanaraptor placidus, one of the Brazilian theropods reviewed by Bittencourt and Langer (2011) in the synthesis on Brazilian Mesozoic dinosaurs and their biogeographic implications in Gondwana.

Santanaraptor placidus, one of the Brazilian theropods reviewed by Bittencourt and Langer (2011) in the synthesis on Brazilian Mesozoic dinosaurs and their biogeographic implications in Gondwana.

Reconstruction of Pycnonemosaurus, an abelisaurid from the Bauru Basin, an example of the second major group of Brazilian theropods (alongside the Araripe coelurosaurs) discussed in the 2011 synthesis.

Reconstruction of Pycnonemosaurus, an abelisaurid from the Bauru Basin, an example of the second major group of Brazilian theropods (alongside the Araripe coelurosaurs) discussed in the 2011 synthesis.

2002

On a theropod dinosaur (Abelisauria) from the continental Cretaceous of Brazil

Kellner, A.W.A. e Campos, D.A. · Arquivos do Museu Nacional

Reports an abelisaurian theropod from the continental Cretaceous of Brazil (Bauru Basin), relevant as a paleobiogeographic comparison point between Gondwanan theropods and Aratasaurus. Offers a panorama of theropod diversity and distribution in the Brazilian Cretaceous.

Skeletal diagram of Pycnonemosaurus nevesi, the Bauru Basin abelisaurid named by Kellner and Campos in 2002, the main focus of the paper on theropods from the Brazilian continental Cretaceous.

Skeletal diagram of Pycnonemosaurus nevesi, the Bauru Basin abelisaurid named by Kellner and Campos in 2002, the main focus of the paper on theropods from the Brazilian continental Cretaceous.

Life reconstruction of Pycnonemosaurus. The 2002 paper enables paleobiogeographic comparison between the large abelisaurids of the Brazilian interior and the small coelurosaurs of the Araripe Basin, including Aratasaurus.

Life reconstruction of Pycnonemosaurus. The 2002 paper enables paleobiogeographic comparison between the large abelisaurids of the Brazilian interior and the small coelurosaurs of the Araripe Basin, including Aratasaurus.

Famous museum specimens

MPSC R 2089 (holótipo) — Museu de Paleontologia Plácido Cidade Nuvens, Universidade Regional do Cariri (URCA), Santana do Cariri, Ceará, Brasil

Sayão et al. 2020 (Wikimedia Commons, CC BY 4.0)

MPSC R 2089 (holótipo)

Museu de Paleontologia Plácido Cidade Nuvens, Universidade Regional do Cariri (URCA), Santana do Cariri, Ceará, Brasil

Completeness: Membro posterior direito articulado: distal do fêmur, proximal da tíbia, metatarsais I–IV parciais, várias falanges e três unguais pedais (~10% do esqueleto)
Found in: 2008
By: Coletado na Mina Pedra Branca (pedreira de gesso), Santana do Cariri (CE); a obtenção do espécime é creditada a Plácido Cidade Nuvens (falecido em 2016)

The museum was founded by Plácido Cidade Nuvens in 1985, donated to URCA in 1991 and houses about 7,000 fossils on display, including the Aratasaurus holotype. The osteohistological description by Sayão et al. (2020) showed the animal died young, aged about 4, still growing.

Classification

Dinosauria
└ Saurischia
└ Theropoda
└ Coelurosauria

Discovery

First fossil
2008
Discoverer
Coletado na Mina Pedra Branca (pedreira de gesso), Santana do Cariri (CE); Plácido Cidade Nuvens, falecido em 2016, foi creditado pela obtenção do espécime
Formal description
2020
Described by
Juliana M. Sayão, Antônio Á.F. Saraiva, Arthur S. Brum, Renan A.M. Bantim, Rafael C.L.P. Andrade, Xin Cheng, Flaviana J. Lima, Helder P. Silva e Alexander W.A. Kellner
Formation
Formação Romualdo (Grupo Santana, Bacia do Araripe)
Region
Ceará
Country
Brasil
📄 Original description paper

Fun fact

Aratasaurus is the only Brazilian dinosaur whose name honours a tragedy: the fire at the Museu Nacional of Rio de Janeiro on 2 September 2018, which destroyed part of Brazil's palaeontological collection. Ara is 'born' in Tupi, atá is 'fire', and -sauros is 'lizard' in Greek, together forming 'lizard born from fire'. The epithet museunacionali completes the tribute to the destroyed institution, while the holotype, housed in Santana do Cariri (Ceará) and not in the Museu Nacional, survived the event. The description was published in 2020, just over a year and a half after the disaster.