''Parvopalus'' (meaning "small

opal Opal is a hydrated amorphous form of silicon dioxide, silica (SiO2·''n''H2O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to the amorphous (chemical) physical structure, it is classified as a ...

") is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus of

monotreme Monotremes () are mammals of the order Monotremata. They are the only group of living mammals that lay eggs, rather than bearing live young. The extant monotreme species are the platypus and the four species of echidnas. Monotremes are typified ...

mammal from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

(

Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...

) Griman Creek Formation of Australia. The genus contains a single species, ''P. clytiei'', known from a partial left

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

Discovery and naming

The ''Parvopalus''

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

specimen, AM F161198, was discovered in 1999 in sediments of the Griman Creek Formation (Wallangulla Sandstone Member) near

Lightning Ridge Lightning Ridge is a small outback town in north-western New South Wales, Australia. Part of Walgett Shire, Lightning Ridge is situated near the southern border of Queensland, about east of the Castlereagh Highway. The Lightning Ridge area is ...

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

, Australia. The specimen consists of part of the left

. In 2024, Flannery et al. described ''Parvopalus clytiei'' as a new genus and species of early monotreme based on these fossil remains. The generic name, ''Parvopalus'', combines the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

words "parvus", meaning "small", and "opalus", meaning "

", referencing the opalized preservation style of the holotype. 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 ...

, ''clytiei'', honours Clytie Smith who has found several opal fossils near the type locality. Several other monotremes are known from the Griman Creek Formation, including ''

Opalios ''Opalios'' (meaning "opal") is an extinct genus of monotreme mammal from the Late Cretaceous (Cenomanian) Griman Creek Formation of Australia. The genus contains a single species, ''O. splendens'', known from a fragmentary left dentary. Disc ...

'' and ''

Dharragarra ''Dharragarra'' (meaning "platypus" in the Gamilaraay language) is an extinct genus of monotreme mammal from the Late Cretaceous (Cenomanian) Griman Creek Formation of Australia. The genus contains a single species, ''D. aurora'', known from a ...

''—which were described in the same

publication To publish is to make content available to the general public.Berne Convention, articl ...

as ''Parvopalus''—as well as ''

Kollikodon ''Kollikodon'' is an extinct species of mammal, considered to be an early monotreme. It is known only from an opalised dentary fragment, with one premolar and two molars '' in situ'', as well as a referred maxillary fragment containing the las ...

'', ''

Steropodon ''Steropodon'' is a genus of prehistoric platypus-like monotreme, or Oviparity, egg-laying mammal. It contains a single species, ''Steropodon galmani'', that lived about 100.2–96.6 million years ago during the Cretaceous period, from early to m ...

'', and ''

Stirtodon ''Stirtodon'' is an extinct genus of monotreme mammal from the Late Cretaceous (Cenomanian) Griman Creek Formation of Australia. The genus contains a single species, ''S. elizabethae'', known from a large isolated premolar. ''Stirtodon'' may be ...

''.

References

{{Taxonbar, from1=Q126123883, from2=Q126123888 Prehistoric monotremes Prehistoric mammal genera Cenomanian life Cretaceous mammals of Australia Fossil taxa described in 2024 Mammals described in 2024 Taxa named by Tim Flannery Taxa named by Tom Rich Taxa named by Patricia Vickers-Rich