Makarkinia

''Makarkinia'' is an extinct genus of lacewings in the family Kalligrammatidae described by Martins-Neto in 1997 from fossils found in the Crato Formation of the Araripe Basin in northeastern Brazil. The genus contains three species dating to the Late Aptian, ''Makarkinia adamsi'', ''Makarkinia kerneri'' and ''Makarkinia irmae''.

History and classification

When first described, ''Makarkinia'' was known from a single fossil wing which is a compression-impression fossil preserved in layers of soft sedimentary rock. Along with other well-preserved insect fossils, the ''Makarkinia'' specimens were collected from layers of the Upper Aptian Crato Formation. The formation is composed of unweathered grey and oxidized yellow limestones, which preserved numerous insects, fish, birds and reptiles as a notable lagerstätten. The area is a preserved inland lake or one of a series of lakes, though the nature as a fresh or salt-water body is uncertain. The depth of the basin has been suggested as either shallow or fairly deep. The basin formed near the center of the supercontinent Gondwana during the early part of the diversification of flowering plants.

The ''M. adamsi'' holotype specimen was preserved in the National Museum of Brazil paleontological collection when first studied. The fossil was described by R. G. Martins-Neto in a 1992 paper on the neuropterans of the Crato Formation, with the species named in it. At the time of description the species was placed into the extinct family Panfiloviidae as ''Panfilovia adamsi''. This placement was changed in a 1997 by Martins-Neto who moved the species to a new genus, ''Makarkinia'' and new subfamily "Makarkiniinae" in Panfiloviidae. Three years later Martins-Neto elevated the subfamily to a full family as Makarkiniidae, though this change was not widely used. It was suggested by Makarkin and Archibald in 2003 and subsequent authors that the genus was closely related to Kalligrammatidae, and moved into the family in 2016 by Günter Bechly and Vladimir Makarkin.

The second species described, ''M. kerneri'', is known from the single holotype specimen residing in the Staatliches Museum für Naturkunde collections at the time of description. The fossil was first studied by Günter Bechly and Vladimir Makarkin who erected the species in a ''Cretaceous Research'' paper published in 2016. They coined the specific epithet ''kerneri'' to honor Andreas Kerner, who owned the fossil until its donation to the Staatliches Museum für Naturkunde.

When ''M. kerneri'' was described, ''Makarkinia'' was the only Kalligrammatidae genus known from the Americas, the other members of the family having been described from Asian and European fossils. Like other kalligrammatids, the environment of ''Makarkinia'' was subtropical to tropical in temperature, and color patterning of the fossils indicates they were daytime fliers. To lessen predation by other animals, large eye spots are found on the hindwings. The genus is the youngest member of the family to be described, living slightly after the last Eurasian genera from the early Aptian of China. ''Makarkinia'' also had the largest wing size of any living or fossil lacewing (indeed of any member of the order Neuroptera) and had an estimated maximum wing length of approximately .

Description

''Makarkinia'' species are distinguished from other genera by the subcostal veinlets which notably curve towards the wing tip. The veinlets are forked with one to four small branches. The hindwings have a large distinct eye spot centered in the wing and surrounded by three concentric circles.

''M. adamsi''

The holotype wing is partially preserved and thought to be a possible forewing, though it is not whole enough to confirm. The estimated wing length is approximately . However, no information was provided as how that inference was obtained, since it is only known from fairly partial fossil not enough to reconstruct whole wing, and wing length-width ratio is completely unknown since that is quite different among kalligrammatids.

''M. kerneri''

The overall size of the ''M. kerneri'' hindwing is smaller than ''M. adamsi'', being and estimated between in full length. The costal vein starts fairly thick in the basal section of the wing and tapers down as it progresses towards the wing tip. The subcostal veinlets below the costa curve towards the wing tip and are fairly widely spaced. Between the major veins on most of the wing are many densely spaced crossveins, with the exception of between the veins at the wings tip end. The wing is covered in a coating of setae, very thick on the outer margins and major veins. On the thin veins running lengthwise along the wing and the crossveins the setae are thinner, arranged into three rows on the veins. The wing membrane has a coating of setae that thins out approaching the wing tip. The color pattering consists of a notable eye-spot that is in diameter, several darker longitudinal stripes and darkening of the costal area.

''M. irmae''

''M. irmae'' is known from long hindwing fragment which preserves eye spot patterning.

References

External links

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{{Portal bar, Paleontology, Insects, Cretaceous

Neuroptera genera
Prehistoric insect genera
Cretaceous insects
Aptian life
Prehistoric arthropods of South America
Early Cretaceous animals of South America
Cretaceous Brazil
Fossils of Brazil
Crato Formation
Fossil taxa described in 2016