''Apolithabatis'' (meaning "fossil ray") 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 spathobatid rays from the

Late Jurassic The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen ...

(

Kimmeridgian In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 154.8 ±0.8 Ma and 149.2 ±0.7 Ma (million years ago). The Kimmeridgian follows the Oxfordian ...

age) Torleite Formation ( Solnhofen Archipelago) of Germany. The genus contains a single species, ''A. seioma'', known from a single complete, well-preserved specimen.

Discovery and naming

The ''Apolithabatis''

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, DMA-JP-2010/007, was discovered in a Rygol Company limestone quarry representing outcrops of the Torleite Formation (Arnstorf Member) near Painten in

Lower Bavaria Lower Bavaria (, ; ) is one of the seven administrative regions of Bavaria, Germany, located in the east of the state. It consists of nine districts and 258 municipalities (including three cities). Geography Lower Bavaria is subdivided into two ...

, South Germany. The fossil is a holomorphic specimen, meaning that it comprises a complete, articulated animal. Based on the absence of

clasper In biology, a clasper is a male anatomical structure found in some groups of animals, used in mating. Male cartilaginous fish have claspers formed from the posterior portion of their pelvic fin which serve to channel semen into the female's ...

s, it can be identified as a female individual. In 2025, Türtscher et al. described ''Apolithabatis seioma'' as a new genus and species of rays in the extinct family Spathobatidae based on these fossil remains. The generic name, ''Apolithabatis'', combines the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

words απολίθωμα (''apolíthoma''), meaning "fossil", and βατίς (''batís''), meaning "ray" or "skate". 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 ...

, ''seioma'', is derived from the Greek word σείω (''seío̱'')—in turn coming from σεισμός (''seismós''), meaning "shake"—referencing the use of explosives to slabs of rock from the outcrop, one of which contained the holotype.

Description

The general bauplan of ''Apolithabatis'' is quite similar to

extant Extant or Least-concern species, least concern is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Exta ...

guitarfish The guitarfish, also referred to as shovelnose rays, are a family, Rhinobatidae, of rays. The guitarfish are known for an elongated body with a flattened head and trunk and small, ray-like wings. The combined range of the various species is tro ...

. It is fairly large for a ray, at in length. ''Apolithabatis'' is characterized by its pointed snout, large, heart-shaped disc, and long tail. It has two similarly-sized

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

s located posterior to the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral (belly) surface of fish, and are the lower of the only two sets of paired fins (the other being the laterally positioned pectoral fins). The pelvic fins are homologous to the hi ...

radials.

Classification

In their

phylogenetic analyses In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as Computational phylogenetics, phylogenetic inference. It infers the relationship among organ ...

, Türtscher et al. (2025) consistently recovered ''Apolithabatis'' as the

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

to '' Aellopobatis'', another Solnhofen ray. They also found support for the assignment of these taxa to a basal clade of other Jurassic European batomorphs outside of the

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 ...

, which they named

Apolithabatiformes Spathobatidae is an extinct Family (biology), family of Batomorphi, rays known from the Late Jurassic epoch. Spathobatidae is the only family within the Order (biology), order Apolithabatiformes. All named genera within this family are known from ...

. Their results are displayed in the

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

below:

References

{{Taxonbar, from1=Q132124170, from2=Q132124171 Spathobatidae Jurassic cartilaginous fish Jurassic fish of Europe Monotypic prehistoric cartilaginous fish genera Fossil taxa described in 2025

Discovery and naming

Description

Classification

See also

References