Anbarrhacus

Anbarrhacus
	A fossil of the species in amber ( holotype )
Temporal occurrence
	Neogen (Mazantic Shale, Balumtum Sandstone)
	approx. 23 to approx. 3 million years
Locations
	Mexico;
Systematics
	Arthropod (arthropoda)
	Millipede (Myriapoda)
	Tapefoot
	Polydesmida
	Anbarrhacus
	Anbarrhacus
Scientific name
	Anbarrhacus adamantis
	Riquelme & Hernández, 2014

Anbarrhacus is an extinct genus of centipedes in the family of Platyrhacidae . The only known specimen comes from fossil finds in Chiapas amber . It has been described as Anbarrhacus adamantis .

Holotype and systematics

Anbarrhacus adamantis was described on the basis of a single fossil , which is preserved as an inclusion in a transparent piece of Mexican amber. At that time, the stone was in the fossil collection of the Instituto Nacional de Antropología e Historia in San Cristóbal de las Casas , Simojovel . The holotype is an almost complete young male from the Guadalupe Victoria Site. There the amber was found in the layers of the Mazantic Shale and Balumtum sandstone with an age of about 23-15 million years. The camps represent deposits from a river near the sea coast and belong to a mangrove ecosystem.

The holotype was described in 2014 by a team led by Francisco Riquelme of the Universidad Autónoma del Estado de Morelos . The generic name is a combination of the Arabic ánbar for amber and rhacus , a common pleasure suffix in the family of Platyrhacidae. The species name adamantis was formed from the neo-Latin adamantus for diamond, an allusion to the pattern on the top of the collum and the metatergites .

A. adamantis is one of three millipedes in Mexican amber that have been described so far. The other two species are Maatidesmus paachtun and Parastemmiulus electron . Other comparable types are known from Dominican amber .

features

The male of A. adamantis is mostly creamy white with a yellow tinge on the labrum and parts of the legs. The sternas alternate between yellowish and brown. The body length is approx. 19.8 mm and includes 17 body segments and the head. The head is slightly wider than the second body segment, the so-called collum. The antennas are made up of seven antennas, which have different shapes and a club-shaped tip. The longest sensor segment is the fifth, then the sixth. The shortest antennae are the first and the seventh. Both antennae 5 and 6 have long setae at the ends and the antennae have four antennae. The upper plates of the body segments after the full area are clearly lobed and form metatergites and paranota. The surface of the Paranota, i.e. the lateral lobes of the metatergites, has a granular surface and a specific diamond-shaped pattern. The segments become wider towards the middle of the body and from two thirds of the body length they decrease in width again to the last limb. the male is so fully grown that segment 7 can be seen pear-shaped gonopods .

Individual evidence

↑ ^a ^b ^c F. Riquelme, J. Alvarado-Ortega, M. Ramos-Arias, M. Hernández, December I, TA Lee-Whiting, JL Ruvalcaba-Sil: A fossil stemmiulid millipede (Diplopoda: Stemmiulida) from the Miocene amber of Simojovel, Chiapas, México . In: Historical Biology . tape 26 , no. 4 , March 15, 2013, ISSN 0891-2963 , p. 415-427 , doi : 10.1080 / 08912963.2013.778843 .

↑ ^a ^b ^c ^d ^e ^f F. Riquelme, M. Hernández-Patricio, A. Martínez-Dávalos, M. Rodríguez-Villafuerte, M. Montejo-Cruz, J. Alvarado-Ortega, JL Ruvalcaba-Sil, L. Zúñiga- Mijangos: Two Flat-Backed Polydesmidan Millipedes from the Miocene Chiapas-Amber Deposit, Mexico . In: PLOS ONE . tape 9 , no. 8 , August 27, 2014, p. e105877 , doi : 10.1371 / journal.pone.0105877 , PMID 25162220 , PMC 4146559 (free full text).

^ F. Riquelme, G. Villegas-Guzmán, E. González-Santillán, V. Córdova-Tabares, OF Francke, D. Piedra-Jiménez, E. Estrada-Ruiz, B. Luna-Castro: New Fossil Scorpion from the Chiapas Amber deposit . In: PLOS ONE . tape 10 , no. 8 , August 5, 2015, p. e0133396 , pp. 1-20 , doi : 10.1371 / journal.pone.0133396 , PMID 26244974 .

Web links

Commons : Anbarrhacus adamantis - Collection of images, videos and audio files

Wikispecies: Anbarrhacus adamantis - species directory

[Riquelme2013-1] F. Riquelme, J. Alvarado-Ortega, M. Ramos-Arias, M. Hernández, December I, TA Lee-Whiting, JL Ruvalcaba-Sil: A fossil stemmiulid millipede (Diplopoda: Stemmiulida) from the Miocene amber of Simojovel, Chiapas, México . In: Historical Biology . tape 26 , no. 4 , March 15, 2013, ISSN 0891-2963 , p. 415-427 , doi : 10.1080 / 08912963.2013.778843 .

[Riquelme2014-2] ↑ ^a ^b ^c ^d ^e ^f F. Riquelme, M. Hernández-Patricio, A. Martínez-Dávalos, M. Rodríguez-Villafuerte, M. Montejo-Cruz, J. Alvarado-Ortega, JL Ruvalcaba-Sil, L. Zúñiga- Mijangos: Two Flat-Backed Polydesmidan Millipedes from the Miocene Chiapas-Amber Deposit, Mexico . In: PLOS ONE . tape 9 , no. 8 , August 27, 2014, p. e105877 , doi : 10.1371 / journal.pone.0105877 , PMID 25162220 , PMC 4146559 (free full text).

[Riquelme2015-3] F. Riquelme, G. Villegas-Guzmán, E. González-Santillán, V. Córdova-Tabares, OF Francke, D. Piedra-Jiménez, E. Estrada-Ruiz, B. Luna-Castro: New Fossil Scorpion from the Chiapas Amber deposit . In: PLOS ONE . tape 10 , no. 8 , August 5, 2015, p. e0133396 , pp. 1-20 , doi : 10.1371 / journal.pone.0133396 , PMID 26244974 .