''Aspidopleura'' 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 ...

parasitic wasp Parasitoid wasps are a large group of hymenopteran superfamilies, with all but the wood wasps ( Orussoidea) being in the wasp-waisted Apocrita. As parasitoids, they lay their eggs on or in the bodies of other arthropods, sooner or later causi ...

in the

Eupelmidae Eupelmidae is a family of parasitic wasps in the superfamily Chalcidoidea. The larvae of the majority are primary parasitoids, commonly on beetle larvae, though many other hosts are attacked, including spiders. Details of the life history varies ...

subfamily Neanastatinae and at present, it contains the single species ''Aspidopleura baltica''. The genus is solely known from the

Early Eocene In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

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 ...

deposits in the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...

region of Europe.

History and classification

''Aspidopleura'' is known from only two fossils, 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 ...

and the

paratype In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype (biology), isotype ...

. The holotype, number "AMNH-JWJ-409", is a single female specimen preserved in a nearly flattened amber block in size. The paratype, number "AMNH-JWJ-410", is also a single female specimen and preserved in a nearly triangular amber block in size. Both amber blocks are currently residing in the

American Museum of Natural History The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interconn ...

paleoentomology 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 ...

collections in

New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...

, USA. The specimens of ''Aspidopleura baltica'' were first studied by Gary A.P. Gibson, with his 2009

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 ...

being published in the journal ''

ZooKeys ''ZooKeys'' is a peer-reviewed open access scientific journal covering zoological taxonomy, phylogeny, and biogeography. It was established in 2008 and the founding editor-in-chief was Terry Erwin (Smithsonian Institution The Smithsonian ...

''. The

generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...

name wash coined by Gary Gibson as a combination of the supposed

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 ''aspido'' meaning "shield" and ''pleuro'', meaning "side". This is in reference to the shape and overall structure of the acropleuron. The proper words for "shield" and "side" in Greek are however ἀσπίς (''aspis'') and πλευρόν (''pleuron'') or πλευρά (''pleura'').Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. The specific epithet "''baltica''" was designated as a reference to the origin of the specimens in amber from the Baltic region.

Description

''Aspidopleura baltica'' is in length when the

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typica ...

is included and a uniform dark brown color. Several areas on each of the females are obscured or missing, with the dorsal view and right side not visible on the holotype, while the paratype has areas of white mold. The

forewing Insect wings are adult outgrowths of the insect exoskeleton that enable insects to fly. They are found on the second and third thoracic segments (the mesothorax and metathorax), and the two pairs are often referred to as the forewings and hindwi ...

s are hyaline in coloration with a large brown spot covering the area behind the marginal and postmarginal veins but fading towards the wing apex. In general ''Aspidopleura'' does not closely resemble extant members of the subfamily Neanastatinae, with a very large

speculum The term speculum, Latin for "mirror", and its plural specula, may refer to: * ''Speculum'' (journal), a journal of medieval studies published by the Medieval Academy of America * Speculum (medical), a medical tool used for examining body cavities ...

in the forewing and possessing a distinct

frenum A frenulum or frenum (: frenula or frena, from the Latin ''frēnulum'', "little bridle", the diminutive of ''frēnum'') is a small fold of tissue that secures the motion of a mobile organ in the body. In human anatomy Frenula on the huma ...

. These features are closer in appearance to females of the subfamily Eupelminae. However the sine patterning on the legs of ''Aspidopleura'' are much closer to that of extant Neanastatinae. Although the life habit of ''Aspidopleura baltica'' is unknown, the short length of the ovipositor and shape of the mandibles, both similar to the genus ''

Anastatus ''Anastatus'' is a large genus of parasitic wasps belonging to the family Eupelmidae. The genus has cosmopolitan distribution. Species *''Anastatus absonus'' *'' Anastatus acherontiae'' *'' Anastatus adamsi'' *'' Anastatus aereicorpus'' Gir ...

'' in subfamily Eupelminae, suggests ''Aspidopleura'' was possibly

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The ent ...

on insect eggs.

References

{{Taxonbar, from=Q4808015 Prehistoric Hymenoptera genera Ypresian insects Eocene insects of Europe Fossil taxa described in 2009 Hymenoptera of Europe

† 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 ...

Baltic amber Monotypic prehistoric insect genera Ypresian genera