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Xiphosura

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EntityQ19430· pop 49· linked from 281 articles

Also known as horseshoe crabs

Xiphosura (; , in reference to its sword-like telson) is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs (a name applied more specifically to the only extant family, Limulidae). They first appear in the fossil record in the Early Ordovician, around 480 million years ago. Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera.

OverviewAI-generated

Xiphosura is a taxon within the animal kingdom, classified under the phylum Arthropoda, class Merostomata, and order Xiphosurida. It belongs to the family Limulidae according to GBIF records, while WoRMS lists it under the family Xiphosuridae. The genus was described by Gronovius in 1764 and is commonly referred to as horseshoe crabs. Its habitat is marine.

The taxon has a start time of about 445 million years ago. According to WoRMS, its current status is unaccepted. In the United States, one record is held by the institution NMMNHS. There are two occurrence records listed in GBIF data.

Synthesized by Vinony from 33 facts across 8 sources: Wikidata, GBIF, iNaturalist, PubMed, Gbif Occ, WoRMS, iDigBio, Vinony graph. Generated from structured data (not the Wikipedia text) and checked against those facts — may still contain errors.

Species

horseshoe crabs

Xiphosura

GENUS

  1. KingdomAnimalia
  2. PhylumArthropoda
  3. ClassMerostomata
  4. OrderXiphosurida
  5. FamilyLimulidae
Habitatmarine
Observations0
Observations recorded2

via GBIF

Museum specimens

Specimen records
1
Collections
NMMNHS
Recorded in
United States

~11 min read

Encyclopedic overview

11 sections
Contents
  • Description
  • Internal anatomy
  • Reproduction
  • Evolutionary history
  • Classification
  • Taxa removed from Xiphosura
  • Cladogram
  • See also
  • References
  • Further reading
  • External links

Xiphosura (; , in reference to its sword-like telson) is an order of arthropods related to arachnids. They are more commonly known as horseshoe crabs (a name applied more specifically to the only extant family, Limulidae). They first appear in the fossil record in the Early Ordovician, around 480 million years ago. Currently, there are only four living species. Xiphosura contains one suborder, Xiphosurida, and several stem-genera.

The group has hardly changed in appearance in hundreds of millions of years; the modern horseshoe crabs look almost identical to prehistoric genera and are considered to be living fossils. The most notable difference between ancient and modern forms is that the abdominal segments in present species are fused into a single unit in adults.

Excerpted from Wikipedia’s “Xiphosura” article, available under the CC BY-SA 4.0 licence.

Gallery (9)