Prolecanitoidea is a

taxonomic 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme of classes (a taxonomy) and the allocation ...

superfamily of

ammonoids Ammonoids are extinct, (typically) coiled-shelled cephalopods comprising the subclass Ammonoidea. They are more closely related to living octopuses, squid, and cuttlefish (which comprise the clade Coleoidea) than they are to nautiluses (family N ...

in the order

Prolecanitida Prolecanitida is an order of extinct ammonoid cephalopods, the major Late Paleozoic group of ammonoids alongside the order Goniatitida. Prolecanitids had narrow shells, discoidal (disc-shaped) to thinly lenticular (lens-shaped). They retained ...

. Prolecanitoidea is one of two superfamilies in the order, along with the younger and more complex Medlicottioidea. The Prolecanitoidea were a low-diversity and morphologically conservative group. They lived from the

Lower Carboniferous Lower may refer to: * ''Lower'' (album), 2025 album by Benjamin Booker *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is sit ...

up to the

Middle Permian The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...

. Their shells are generally smooth and discoidal, with a rounded lower edge, a moderate to large umbilicus, and goniatitic to ceratitic sutures. Suture complexity varies from 10 up to 22 total lobes (each side of a whorl combined); new lobes are added from subdivision of saddles adjacent to the original main umbilical lobe. Daraelites diagram

The Prolecanitoidea encompasses two related families, the ancestral Prolecanitidae (lower

Tournaisian The Tournaisian is in the ICS geologic timescale the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. The Tournaisian age lasted from Ma to Ma. It is preceded by the Famennian (the uppermost st ...

–

Bashkirian The Bashkirian is in the International Commission on Stratigraphy geologic timescale the lowest stage (stratigraphy), stage or oldest age (geology), age of the Pennsylvanian (geology), Pennsylvanian. The Bashkirian age lasted from to Mega annu ...

? stages) and the derived

Daraelitidae The Daraelitidae form a family in the ammonoid order Prolecanitida from the Upper Mississippian - Middle Permian characterized by discoidal shells with no prominent sculpture, moderately large umbilicus, and goniatitic or ceratitic sutures with a ...

(

Viséan The Visean, Viséan or Visian is an age in the ICS geologic timescale or a stage in the stratigraphic column. It is the second stage of the Mississippian, the lower subsystem of the Carboniferous. The Visean lasted from to Ma. It follows ...

–

Wordian In the geologic timescale, the Wordian is an age or stage of the Permian. It is the middle of three subdivisions of the Guadalupian Epoch or Series. The Wordian lasted between and million years ago (Ma). It was preceded by the Roadian and fo ...

stages). Prolecanitids and daraelitids differ primarily in the complexity of the suture: Prolecanitids are simpler goniatitic forms, with rounded saddles, pointed lobes, and an undivided ventral lobe. Daraelitids, conversely, often have a trifid (three-pronged) ventral lobe and a higher number of lobes as a whole, some of which are ceratitic (finely serrated). Daraelitids are probably ancestral to

Ceratitida Ceratitida is an order that contains almost all ammonoid cephalopod genera from the Triassic as well as ancestral forms from the Upper Permian, the exception being the phylloceratids which gave rise to the great diversity of post-Triassic ammon ...

, the dominant order of

Triassic The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

ammonoids. A third proposed family, the Mississippian-age Prodromitidae, is occasionally also placed within the order Prolecanitida. The affinities or

monophyly In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent comm ...

of this family are uncertain due to drastic changes in their suture patterns through

ontogeny Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the ovum, egg to adult. The term can also be used to refer to t ...

. More recently, prodromitids have been moved to the

goniatite Goniatids, informally goniatites, are ammonoid cephalopods that form the order Goniatitida, derived from the more primitive Agoniatitida during the Middle Devonian some 390 million years ago (around Eifelian stage). Goniatites (goniatitids) su ...

suborder

Tornoceratina Tornoceratina is one of two suborders included in the Goniatitida, characterized by generally involute, subdiscoidal shells and by sutures in which the ventral ones are undivided. Sutural lobes increase in number during the course of life of th ...

. The Prolecanitoidea were previously known by the name Prolecanitaceae, prior to the recent ruling of the

ICZN The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its formal author, t ...

regarding superfamilies. The suffix -oidea was previously used for some time in invertebrate taxonomies as the ending for subclasses, e.g. Ammonoidea. The Medlicottioidea are also sometimes known as the suborder Prolecanitina.

References

* * Miller, Furnish, and Schindewolf, 1957; Paleozoic Ammonoidea, esp. superfamily Prolecanitaceae, L69, in The Treatise on Invertebrate Paleontology, Part L, Ammonoidea. * Saunders and Work; Abstract: Evolution of shell morphology and suture complexity in Paleozoic prolecanitids..

Prolecanitida Prehistoric animal superfamilies Late Devonian first appearances Late Devonian animals Guadalupian extinctions {{Prolecanitida-stub