Harpetida (lat.) - a detachment of trilobites . Paleozoic group: found in the Cambrian , Ordovician , Silurian, and Devonian periods . The name of the detachment comes from the word "sickle" (Harpe) due to the crescent shape of the buccal horns [1] [2] [3] .
† Harpetida | ||||||||||
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 Trilobite Harpetidae | ||||||||||
| Scientific classification | ||||||||||
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| Latin name | ||||||||||
| Harpetida Ebach and McNamara 2002 | ||||||||||
| Families | ||||||||||
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Content
- 1 Description
- 2 Systematics
- 3 Geochronology
- 4 notes
- 5 Literature
- 6 References
Description
The thorax (trunk section) typically consists of 12 or more segments (up to 29). Cheeks lengthen backwards in the form of sickle-shaped backward-curved horns (buccal horns). The eyes are not developed or weak. The convex part of the head shield, or glabella, narrows forward and carries from 1 to 3 grooves. The rounded head shield [1] [2] [3] .
Harpes
Harpides
Systematics
About 30 births. The order was recently (Ebach & McNamara, 2002) isolated from the taxon Ptychopariida , in which it previously had the status of the suborder Harpina [1] [4] [5] .
- Entomaspididae
- Childbirth: Baikadamaspis, Entomaspis (= Hypothetica)
- Harpetidae
- Childbirth: Arraphus, Bohemoharpes (= Declivoharpes; = Unguloharpes), Bowmania, Brachyhipposiderus, Conococheaguea, Dolichoharpes, Dubhglasina (= Australoharpes; = Sinoharpes), Eoharpes (/ Harpina), Eotrinucleus, Harpes (= Rioheret) (/ Platyharpes; = Harpesoides; = Metaharpes; = Paraharpes; = Thorslundops; = Wegelinia), Kathrynia, Kielania (= Lowtheria), Lioharpes (= Fritchaspis), Paleoharpes, Scotoharpes (= Aristoharpes; = Selenoharpes)
- Harpididae (= Loganopeltidae )
- Childbirth: Chencunia, Dictyocephalites, Fissocephalus, Harpides, Harpidoides, Kitatella, Loganopeltis, Loganopeltoides, Metaharpides, Paraharpides, Pscemiaspis
Geochronology
The group appeared about 500 million years ago in the middle of the Cambrian period and completely died out at the end of the Devonian period [1] .
| Precambrian | Phanerozoic | Aeon | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Paleozoic | Mesozoic | Cenozoic | Era | ||||||||||
| Cambrian | Ordo wick | Forces ur | Devonian | Carbon | Permian | Triassic | Yura | a piece of chalk | Paleo gene | Neo gene | F-d | ||
| 4570 | 541 | 485.4 | 443.4 | 419.2 | 358.9 | 298.9 | 252.2 | 201.3 | 145.0 | 66.0 | 23.03 | million years ← | |
| 2,588 | |||||||||||||
Notes
- ↑ 1 2 3 4 ORDER LICHIDA (sensu Fortey 1997 ) . www.trilobites.info. Date of treatment February 9, 2014.
- ↑ 1 2 Drushchits V.V. Paleontology of invertebrates. - Moscow: Publishing House of Moscow State University, 1974. - 528 p. - 3600 copies.
- ↑ 1 2 SM Gon III. Pictorial guide to the order Harpetida Neopr (January 1, 2008). Date of treatment February 9, 2014.
- ↑ Ebach, MC & KJ McNamara. 2002. A systematic revision of the family Harpetidae (Trilobita). Records of the Western Australian Museum 21: 135-167.
- ↑ Beu, AG 1971. Cassidae and Harpidae: Two family group homynyms in Molluska and Arthropoda. ZN (S.) 1938. Bulletin of Zoological Nomenclature 28: 564-586.
Literature
- Jell, PA & JM Adrain. (2003). Available generic names for trilobites. // Memoirs of the Queensland Museum 48 (2): 331–553.
Links
- Order Harpetida Ebach and McNamara 2002 . Paleobiology Database . paleobiodb.org. Date of treatment February 9, 2014.