''Electrinocellia'' 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 ...

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

snakefly Snakeflies are a group of predatory insects comprising the order Raphidioptera with two extant families: Raphidiidae and Inocelliidae, consisting of roughly 260 species. In the past, the group had a much wider distribution than it does now; snak ...

in the family

Inocelliidae Inocelliidae is a small family (biology), family of snakeflies containing 8 genera of which one is known only from fossils. They are commonly known as inocelliid snakeflies. The largest known species is ''Fibla carpenteri'' known from fossils fo ...

containing the single species ''Electrinocellia peculiaris'' and known from

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

aged

Baltic amber Baltic amber or succinite is amber from the Baltic region, home of its largest known deposits. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that this forested region provided the re ...

History and classification

The genus is known from only the

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 ...

, a single dark brown male specimen, deposited in the

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

Museum of Comparative Zoology The Museum of Comparative Zoology (formally the Agassiz Museum of Comparative Zoology and often abbreviated to MCZ) is a zoology museum located on the grounds of Harvard University in Cambridge, Massachusetts. It is one of three natural-history r ...

as specimen number 51. The specimen was first studied and described by the prolific paleoentomologist Dr. Frank M. Carpenter, while he was curator of the Harvard paleoentomological collections. The genus was named from the Latin ''electrum'' meaning "amber" and '' Inocellia'', the type genus for Inocelliidae. The species name ''peculiaris'' is a reference to the enigmatic nature of the species when first studied. When first described the species was placed in ''Inocellia'' as ''Inocellia peculiaris''. In his

type description A species description is a formal scientific description of a newly encountered species, typically articulated through a scientific publication. Its purpose is to provide a clear description of a new species of organism and explain how it differ ...

of the species, Dr. Carpenter noted a number of odd features which do not conform well with extant ''Inocellia'' species. The specimen possesses antennae placed far back on the head, lacks

ocelli A simple eye or ocellus (sometimes called a pigment pit) is a form of eye or an optical arrangement which has a single lens without the sort of elaborate retina that occurs in most vertebrates. These eyes are called "simple" to distinguish the ...

, a

pterostigma The pterostigma (plural: pterostigmata) is a group of specialized cells in the outer wings of insects, which are often thickened or coloured, and thus stand out from other cells. It is particularly noticeable in dragonflies, but present also in ...

without crossvein, all structures found in ''Inocellia''. The genitalia are also very close in structure to ''Inocellia''. However the species also has distinct vein structures, and an overall head shape which is less quadrate, features not found in ''Inocellia''. The size of the specimen is also notably smaller than other species of ''Inocellia'', the fore wing being only long and wide. Dr. Carpenter therefore placed the species in ''Inocellia'' and noted his reservations regarding the placement but did not feel that the differences were enough to warrant creation of a new genus. Though they did not move the species to a new genus, Horst Aspöck, Ulrike Aspöck and Hubert Rausch in the 1991 work ''Die Raphidiopteren der Erde'' also noted the very odd nature of the species and questioned its placement in ''Inocellia''. Dr Michael S. Engel restudied the type specimen and moved the species in a 1995 paper published in the entomology journal Psyche, 39 years after the type description was published in the same journal. Dr. Engel, noting the oddities moved the species to a new genus ''Electrinocellia'' which he in turn placed in the monotypic subfamily Electrinocellinae. This subfamily is a

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 the rest of the genera in Inocelliidae, which are in the subfamily Inocelliidinae.

References

{{Taxonbar, from=Q5357889

† A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already been used. The symbol is also used to indicate death (of people) or extinction (of species or languages). It is one of the mo ...

Eocene insects of Europe Fossil taxa described in 1995 Baltic amber Monotypic prehistoric insect genera Taxa named by Michael S. Engel