Baikuris

Last updated

Baikuris
Temporal range: Albian–Campanian, 100–72.1  Ma
Baikuris mandibularis PIN3730-5 whole.jpg
B. mandibularis male, holotype
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily:† Sphecomyrminae
Tribe:† Sphecomyrmini
Genus:† Baikuris
Dlussky, 1987
Type species
Baikuris mandibularis
Species
  • B. caseiGrimaldi, Agosti & Carpenter, 1997
  • B. mandibularisDlussky, 1987
  • B. maximusPerrichot, 2015
  • B. mirabilisDlussky, 1987
  • B. ocellantisSosiak et al., 2024

Baikuris is an extinct genus of ant in the Formicidae subfamily Sphecomyrminae, and is currently placed in the tribe Sphecomyrmini. The genus contains four described species: the type species Baikuris mandibularis, along with Baikuris casei, Baikuris maximus, Baikuris mirabilis, B. ocellantis.

Contents

History and classification

The type species B. mandibularis along with B. mirabilis were identified from adults preserved as inclusion in Taimyr amber. [1] The fossils of both species were collected on an expedition to the Taimyr peninsula. The ambers of the peninsula occur in the upper levels of the Kheta Formation, which is exposed in a number of locations in the Taimyr region. Age estimates of the Kheta Formation are between the Coniacian and Santonian, and the ambers are found consistently in the upper most units, giving a Santonian age range for the inclusions. [1] Based on the flora and fauna of the Ledyanaya and Mutino Formations which surround the Kheta formation, the paleoforest likely has a humid and warm temperate climate with the tees growing along river banks. While the resin producing trees have not been identified, the resins were likely dropped into the river systems and buried quickly in deltaic sediments. [1] [2]

Both the holotype and the second specimen for B. casei are adult males which have been preserved as inclusions in transparent chunks of New Jersey amber. The amber specimens were recovered from deposits of the South Amboy Fire Clay, part of the Raritan Formation. New Jersey amber has been dated to approximately 90 to 94 mya, placing it in the Turonian of the Late Cretaceous. Analysis of the amber composition indicates it originated as cupressaceous resins which were deposited in lagoons and salt water marshes along the Cretaceous eastern seaboard. [3]

The fossil of B. maximus was discovered preserved as an inclusion in a transparent chunk of Charentese amber. [4] The amber is thought to have been formed from resins of the extinct Pinales tree family Cheirolepidiaceae and possibly from the living family Araucariaceae. Paleoecology based on Charentese amber inclusions indicate a shore line mangrove type forest that was of a subtropical to warm temperate climate, with occasional dry periods. [5] The amber specimens are recovered from deposits exposed in quarries, road constructions, and beach exposures in the Charente-Maritime region of coastal France, notably at Archingeay. [6] Dating of the amber has been done through pollen analysis and it is generally accepted to be approximately 100 million years old. [5] [7]

An additional amber specimen with partial fossils of six males of an unidentified species was described in 2013, and named as Baikuris ocellantis in 2024. The amber was recovered from sediments of the Black Creek Formation along the Neuse River in North Carolina. Early dating of the formation places North Carolina amber between 83.6 and 72.1 million years old, in the Campanian, with later refimement of the deposts giving a date of 77 million years old. [8] These males are the youngest occurrence of Baikurus identified, and they are of similar age to the Canadian Grassy Lake amber, though Baikurus has not been found in that amber. Both the North Carolina and B. casei males are preserved as groups of winged males, indicating that the genus displayed colonial behavior and likely had daytime nuptial fights similar to modern ants. [9]

Description

B. mandibularis head in profile Baikuris mandibularis PIN3730-5 head.jpg
B. mandibularis head in profile

The genus is known from adult males preserved in amber only. [4] All species of Baikuris have kidney to oval shaped eyes. The narrow mandibles have a chewing edge that are parallel to each other and lacking teeth. At the base of the outer mandible surface is a ridge and oval area that may be the opening for the mandibular gland. The labial palps, visible on the B. casei fossil, have four segments, while the maxillary palps are elongated and have six segments each. On both the mid and hind leg sets, the end of the femurs have developed into additional trochantellus segments. [4]

B. casei

Adult males of B. casei are approximately 7.5 mm (0.30 in) and fore-wings that are 5 mm (0.20 in). Unlike males of B. mandibularis and B. miribilis, the compound eyes of B. casei are oval in shape. Also in contrast, B. casei fore-wings do not have any crossveins between the cells 1r and 2r. The antennae have 13 segment total, with segment three being the longest and the pedicel being the shortest. [3]

The specific epithet casei was coined in honor of Gerard R. Case, who collected New Jersey amber from a number of localities between 1962 and 1986 and who worked to get the ambers studied in depth. [3]

B. mandibularis

The three males described are all included in a single piece of amber labeled PIN 3730/5. The average length of the three is between 4–5 mm (0.16–0.20 in), the smallest of the described species. [4] The approximately 3 mm (0.12 in) fore wings of the holotype show several areas of folding and deformation. [10] The area of the fore wing extending from the wing tip to the apex of the pterostigma curves away from the body towards the amber surface. The lower edge of the wing on the apical side of the anal vein is curved in towards the body. [10]

B. maximus

B. maximus holotype Baikuris maximus IGRARC112-1 whole.jpg
B. maximus holotype

B. maximus is distinct from the other three species in that the males are distinctly larger at 11.5 mm (0.45 in), while the other species are at most 8 mm (0.31 in). There is also a distinct downward projection on the underside of the petiole node. The antennae are 10.5 mm (0.41 in) long with a filiform structure to the segments, though only the left antenna is preserved. The clypeus and mandibles are partially obscured and details difficult to distinguish. The mandibles seem to be small, with straight sides and having a small tooth just below the tip end. [4]

The species name was taken from the Latin maximus, which translates as "biggest" in reference to the size of the species. [4]

B. mirabilis

This Taimyr species is described from a single partial male in amber specimen PIN 3730/8. The holotype has a total length of around 8 mm (0.31 in), and the petiole is distinctly elongated. [3] The wings are preserved, though the veination is faint in many areas, such as the r-rs vein and the 3cu vein. [4] The fore wings are an estimated 4.7 mm (0.19 in) long and show distinct darkening in the middle area. As a result of cleavages both the base and tip areas of the left fore wing are missing. The right wing is complete and distinct, despite the inward curving of the wing tip area. There are at least twelve hamuli on the wing, but fissures obscure the wing so a total number cannot be determined. [10]

B. ocellantis

The B. ocellantis fossils from North Carolina have a mix of features seen in both the two Taimyr amber species and in B. casei. Like B. mirabilis and B. mandibularis the costal vein in the fore wing extends to the pterostigma, while it does not it B. casei. The eyes of the North Carolina fossils are oval in outline though, which is only seen in B. casei and not the Taimyr amber species. Unlike any of the other Baikuris species, the North Carolina fossils have short labial and long maxillary palps. The combination of characters is not seen in any of the other species, and they were not placed into a new species in the 2013 paper, [9] and did not get formally named until 2024. [8]

Related Research Articles

<i>Sphecomyrma</i> Extinct genus of ants

Sphecomyrma is an extinct genus of ants which existed in the Cretaceous approximately 79 to 92 million years ago. The first specimens were collected in 1966, found embedded in amber which had been exposed in the cliffs of Cliffwood, New Jersey, by Edmund Frey and his wife. In 1967, zoologists E. O. Wilson, Frank Carpenter and William L. Brown, Jr. published a paper describing and naming Sphecomyrma freyi. They described an ant with a mosaic of features—a mix of characteristics from modern ants and aculeate wasps. It possessed a metapleural gland, a feature unique to ants. Furthermore, it was wingless and had a petiole which was ant-like in form. The mandibles were short and wasp-like with only two teeth, the gaster was constricted, and the middle and hind legs had double tibial spurs. The antennae were, in form, midway between the wasps and ants, having a short first segment but a long flexible funiculus. Three additional species, S. canadensis, S. mesaki and S. nexa, were described in 1985, 2005, and 2024, respectively.

<span class="mw-page-title-main">Sphecomyrminae</span> Extinct subfamily of ants

Sphecomyrminae is an extinct subfamily of ants in family Formicidae known from a series of Cretaceous fossils found in North America, Europe, and Asia. Sphecomyrminae contains eight genera, divided into two tribes Sphecomyrmini and Zigrasimeciini. The tribe Sphecomyrmini contains the six genera Armania, Cretomyrma, Gerontoformica, Orapia, Pseudarmania and Sphecomyrma; while Zigrasimeciini contains Boltonimecia and Zigrasimecia. A number of taxa have been removed from the subfamily and placed either in other subfamilies or are now treated as incertae sedis in Formicidae.

<span class="mw-page-title-main">Haidomyrmecinae</span> Extinct subfamily of ants

Haidomyrmecinae, occasionally called hell ants, are an extinct subfamily of ants (Formicidae) known from Cretaceous fossils found in ambers of North America, Europe, and Asia, spanning the late Albian to Campanian, around 100 to 79 million years ago. The subfamily was first proposed in 2003, but had been subsequently treated as the tribe Haidomyrmecini and placed in the extinct ant subfamily Sphecomyrminae. Reevaluation of the Haidomyrmecini in 2020 lead to the elevation of the group back to subfamily. The family contains the nine genera and 13 species.

<i>Brownimecia</i> Cretaceous ant genus described from amber fossils

Brownimecia is an extinct genus of ants, the only genus in the tribe Brownimeciini and subfamily Brownimeciinae of the Formicidae. Fossils of the identified species, Brownimecia clavata and Brownimecia inconspicua, are known from the Middle Cretaceous to Late Cretaceous of North America. The genus is one of several ants described from Middle Cretaceous ambers of New Jersey. Brownimecia was initially placed in the subfamily Ponerinae, until it was transferred to its own subfamily in 2003; it can be distinguished from other ants due to its unusual sickle-like mandibles and other morphological features that makes this ant unique among the Formicidae. B. clavata is also small, measuring 3.43 millimetres (0.135 in), and a stinger is present in almost all of the specimens collected. The morphology of the mandibles suggest a high level of feeding specialization.

<i>Zigrasimecia</i> Extinct genus of ants

Zigrasimecia is an extinct genus of ants which existed in the Cretaceous period approximately 98 million years ago. The first specimens were collected from Burmese amber in Kachin State, 100 kilometres (62 mi) west of Myitkyina town in Myanmar. In 2013, palaeoentomologists Phillip Barden and David Grimaldi published a paper describing and naming Zigrasimecia tonsora. They described a dealate female with unusual features, notably the highly specialized mandibles. Other features include large ocelli, short scapes, 12 antennomeres, small eyes, and a clypeal margin that has a row of peg-like denticles. The genus Zigrasimecia was originally incertae sedis within Formicidae until a second species, Zigrasimecia ferox, was described in 2014, leading to its placement in the subfamily Sphecomyrminae. Later, it was considered to belong to the distinct subfamily Zigrasimeciinae.

<i>Haidomyrmodes</i> Extinct genus of ants

Haidomyrmodes is an extinct genus of ant in the formicid subfamily Haidomyrmecinae, and is one of only nine genera placed in the subfamily Haidomyrmecinae. The genus contains a single described species, Haidomyrmodes mammuthus. Haidomyrmodes is known from several Middle Cretaceous fossils which have been found in Europe.

<i>Burmomyrma</i> Genus of ants

Burmomyrma is an extinct genus of aculeate hymenopteran, suggested to be an ant. The genus contains a single described species, Burmomyrma rossi. Burmomyrma is known from a single Middle Cretaceous fossil which was found in Asia.

<span class="mw-page-title-main">Maimetshidae</span> Extinct family of wasps

Maimetshidae is an extinct family of wasps, known from the Cretaceous period. While originally considered relatives of Megalyridae, they are now considered to probably be close relatives of Trigonalidae.

<i>Archimyrmex</i> Extinct genus of ants

Archimyrmex is an extinct genus of ant in the formicid subfamily Myrmeciinae, described by palaeoentomologist Theodore Cockerell in 1923. The genus contains four described species, Archimyrmex rostratus, Archimyrmex piatnitzkyi, Archimyrmex smekali and Archimyrmex wedmannae. Archimyrmex is known from a group of Middle Eocene fossils which were found in North America, South America, and Europe. The genus was initially placed in the subfamily Ponerinae, but it was later placed in Myrmeciinae; it is now believed to be the ancestor of the extant primitive genus Myrmecia from Australia. Despite this, Archimyrmex is not a member to any tribe and is regarded as incertae sedis within Myrmeciinae. However, some authors believe Archimyrmex should be assigned as incertae sedis within Formicidae. These ants can be characterised by their large mandibles and body length, ranging from 13.2 to 30 mm. They also have long, thin legs and an elongated mesosoma (thorax) and petiole.

Armaniinae is subfamily of extinct ant-like hymenopterans known from a series of Cretaceous fossils found in Asia and Africa. It is usually treated as one of the stem-group subfamilies in family Formicidae, although some myrmecologists treat it as a distinct family. A 2007 study analysing petiole and antenna morphology led to the proposal that at least some of the armaniid genera be placed in Sphecomyrminae, although others are unconvinced by the arguments and retain Armaniinae. The subfamily contains seven genera with fourteen described species.

<i>Myanmyrma</i> Extinct genus of ants

Myanmyrma is an extinct genus of ants not placed into any Formicidae subfamily. Fossils of the single known species, Myanmyrma gracilis, are known from the Middle Cretaceous of Asia. The genus is one of several ants described from Middle Cretaceous ambers of Myanmar.

<i>Protopone</i> Extinct genus of ants

Protopone is an extinct genus of ants in the formicid subfamily Ponerinae described from fossils found in Europe and Asia. There are seven described species placed into the genus, Protopone? dubia, Protopone germanica, Protopone magna, Protopone oculata, Protopone primigena, Protopone sepulta, and Protopone vetula. Protopone is one several Lutetian Ponerinae genera.

Burmaleon is an extinct genus of lacewing in the family Osmylidae known from fossils found in Asia. The genus contains a single species, Burmaleon magnificus.

<i>Gerontoformica</i> Extinct genus of ants

Gerontoformica is an extinct genus of stem-group ants. The genus contains thirteen described species known from Late Cretaceous fossils found in Asia and Europe. The species were described between 2004 and 2016, with a number of the species formerly being placed into the junior synonym genus Sphecomyrmodes.

<i>Camelomecia</i> Extinct genus of ants

Camelomecia is an extinct genus of stem-group ants not placed into any Formicidae subfamily. Fossils of the single known species, Camelomecia janovitzi, are known from the Middle Cretaceous of Asia. The genus is one of several ants described from Middle Cretaceous ambers of Myanmar.

Prosisyrina is an extinct genus of lacewing in the neuropteran family Sisyridae. The genus contains two described species, Prosisyrina sphinga and Prosisyrina sukachevae. Prosisyrina is known from a group of Late Cretaceous fossils which were found in Asia.

<i>Dlusskyidris</i> Extinct genus of ants

Dlusskyidris is an extinct genus of ant in the Formicidae subfamily Sphecomyrminae, and is one of the five genera placed in the tribe Sphecomyrmini. The genus contains a single described species, Dlusskyidris zherichini, and is known from three Late Cretaceous fossils which have been found in northern Russia.

<i>Ceratomyrmex</i> Extinct genus of ants

Ceratomyrmex is an extinct genus of ant in the Formicidae subfamily Haidomyrmecinae. The genus contains a single described species Ceratomyrmex ellenbergeri and is known from several Late Cretaceous fossils which have been found in Asia.

<i>Boltonimecia</i> Extinct genus of ants

Boltonimecia is an extinct genus of ant in the formicid subfamily Zigrasimeciinae. The genus contains a single described species, Boltonimecia canadensis, and is known from a single Late Cretaceous fossil which was found in Canada. The type species was originally described as a species of the extinct genus Sphecomyrma under the combination Sphecomyrma canadensis.

<span class="mw-page-title-main">Zigrasimeciinae</span> Extinct subfamily of ants

Zigrasimeciinae is a subfamily of ants, known from the Cretaceous period, originally named as the tribe Zigrasimeciini within the subfamily Sphecomyrminae by Borysenko, 2017, it was elevated to full subfamily in 2020. It contains three described genera. They are sometimes known as iron-maiden ants in reference to their densely spiked mouthparts, reminiscent of an iron maiden torture device, that were likely used to trap prey. Boltonimecia canadensis was described from Campanian Canadian amber out of Alberta, Canada, while the species of Protozigrasimecia and Zigrasimecia are both exclusively known from Cenomanian Burmese amber found in Myanmar.

References

  1. 1 2 3 Perkovsky, E.E.; Makarkin, V.N. (2015). "First confirmation of spongillaflies (Neuroptera: Sisyridae) from the Cretaceous". Cretaceous Research. 56: 363–371. Bibcode:2015CrRes..56..363P. doi:10.1016/j.cretres.2015.06.003.
  2. ↑ Poinar, G.O. Jr. (1992). Life in Amber. Stanford University Press. p. 59. ISBN   978-0-8047-2001-4.
  3. 1 2 3 4 Grimaldi, D.; Agosti, D.; Carpenter, J. M. (1997). "New and rediscovered primitive ants (Hymenoptera, Formicidae) in Cretaceous amber from New Jersey, and their phylogenetic relationships". American Museum Novitates (3208): 1–43.
  4. 1 2 3 4 5 6 7 Perrichot, V. (2015). "A new species of Baikuris (Hymenoptera: Formicidae: Sphecomyrminae) in mid-Cretaceous amber from France" (PDF). Cretaceous Research. 52 (part B): 585–590. Bibcode:2015CrRes..52..585P. doi:10.1016/j.cretres.2014.03.005. S2CID   140675379.
  5. 1 2 Peris, D.; Ruzzier, E.; Perrichot, V.; Delclòs, X. (2016). "Evolutionary and paleobiological implications of Coleoptera (Insecta) from Tethyan-influenced Cretaceous ambers". Geoscience Frontiers. 7 (4): 695–706. Bibcode:2016GeoFr...7..695P. doi: 10.1016/j.gsf.2015.12.007 . hdl: 2445/100747 .
  6. ↑ Nel, A.; Perrault, G.; Perrichot, V.; Néradeau, D. (2004). "The oldest ant in the lower cretaceous amber of Charente-maritime (SW France) (Insecta: Hymenoptera: Formicidae)". Geologica Acta. 2 (1): 23–29.
  7. ↑ Perrichot, V.; Néraudeau, D.; Tafforeau, P. (2010). "Chapter 11: Charentese amber". In Penney, D. (ed.). Biodiversity of Fossils in Amber from the Major World Deposits. Siri Scientific Press. pp. 192–207. ISBN   978-0-9558636-4-6.
  8. 1 2 Sosiak, C.; Cockx, P.; Aragonés Suarez, P.; McKellar, R.; Barden, P. (2024). "Prolonged faunal turnover in earliest ants revealed by North American Cretaceous amber". Current Biology. doi:10.1016/j.cub.2024.02.058. PMID   38521061.
  9. 1 2 Krynicki, V.E. (2013). "Primitive ants (Hymenoptera: Sphecomyrminae) in the Campanian (Late Cretaceous) of North Carolina (USA)". Life: The Excitement of Biology. 1 (3): 156–165. doi: 10.9784/LEB1(3)Krynicki.03 .
  10. 1 2 3 Perfilieva, K.S. (2011). "New Data on the Wing Morphology of the Cretaceous Sphecomyrminae Ants (Hymenoptera: Formicidae)". Paleontological Journal. 45 (3): 275–283. Bibcode:2011PalJ...45..275P. doi:10.1134/S0031030111030117. ISSN   0031-0301. S2CID   83899478.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.