extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed 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 "unispec ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
snakefly
Snakeflies are a group of Predation, predatory insects comprising the order (biology), order Raphidioptera with two extant families: Raphidiidae and Inocelliidae, consisting of roughly 260 species. In the past, the group had a much wider distrib ...
in the family
Inocelliidae
Inocelliidae is a small 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 found in baltic amb ...
containing the single species ''Electrinocellia peculiaris'' and known from
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
aged
Baltic amber
The Baltic region is home to the largest known deposit of amber, called Baltic amber or succinite. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that these forests created more than 1 ...
.
History and classification
The genus is known from only the
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
, a single dark brown male specimen, deposited in the
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...
Museum of Comparative Zoology
A museum ( ; plural museums or, rarely, musea) is a building or institution that cares for and displays a collection of artifacts and other objects of artistic, cultural, historical, or scientific importance. Many public museums make these ...
as specimen number 51. The specimen was first studied and described by the prolific
paleoentomologist
The most recent understanding of the evolution of insects is based on studies of the following branches of science: molecular biology, insect morphology, paleontology, insect taxonomy, evolution, embryology, bioinformatics and scientific computing ...
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
''Inocellia'' is the Palaearctic type genus of the family Inocelliidae: belonging to the snakeflies and their allies. Distribution records are from mainland Europe and Asia: especially in the more temperate zones. 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 description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...
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 (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-l ...
, a
pterostigma
The pterostigma (plural: pterostigmata) is a group of specialized cells in the outer insect wing, wings of insects, which are often thickened or coloured, and thus stand out from other cells. It is particularly noticeable in dragonfly, dragonfli ...
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
Psyche (''Psyché'' in French) is the Greek term for "soul" (ψυχή).
Psyche may also refer to:
Psychology
* Psyche (psychology), the totality of the human mind, conscious and unconscious
* ''Psyche'', an 1846 book about the unconscious by Car ...
, 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 t ...
to the rest of the genera in Inocelliidae, which are in the subfamily Inocelliidinae.