Ultimate legs

Ultimate legs are a pair of modified rear legs unique to centipedes. Although they do not aid in locomotion, ultimate legs are used for a variety of uses, and their morphology varies accordingly.

Ultimate legs
Details
SynonymsAnal legs, caudal legs, terminal legs
OriginsLegs
FunctionVaried: defensive postures, mating rituals, anchoring
Anatomical terminology

Sexual dimorphism is frequently present.[1][2][3][4]

Usage
Warning postures of Scolopendra spinosissima and S. galapagoensis

As a defence against predators

In many species, ultimate legs are used in warning postures to scare off predators. The ultimate legs are raised, splayed, and sometimes waved back and forth.[1][2] The presence of spines on the ultimate legs of some species also serves a defensive role- as Lewis & Kronmüller (2015) put it, "a predator approaching from behind would come into contact with a battery of spines."[2]

Scolopendra dehaani hanging from just its ultimate legs.

For suspension

Some species use their ultimate legs to hang or anchor themselves from trees or other desired objects. This has been recorded as playing a role in predation; the centipede suspends itself in the air and swings back and forth to capture prey.[2]

In contact with other centipedes
Scolopendra galapagoensis interlocking ultimate legs before mating.

Before mating, many species of Scolopendrid centipedes interlock ultimate legs. A similar behaviour has been recorded in ordinary meetings, wherein each centipede grasps the other's trunk with its ultimate legs. This possibly serves as a way to defuse aggression, and in some species may be held for several minutes.[2]

During mating, Scutigera coleoptrata raise and lower their ultimate legs, along with their antennae.[3]

As a means of sound production

Members of the genus Alipes stridulate their leaf-like ultimate legs, probably as a way to warn off predators. The legs continue to stridulate for up to half a minute if detached from the centipede.[2]

The ultimate legs of Rhysida immarginata togoensis emit a faint creaking or squeaking sound when detached and bent.[2]

References
  1. Kenning, Matthes; Schendel, Vanessa; Müller, Carsten H. G.; Sombke, Andy (2019-01-14). "Comparative morphology of ultimate and walking legs in the centipede Lithobius forficatus (Myriapoda) with functional implications". Zoological Letters. 5 (1): 3. doi:10.1186/s40851-018-0115-x. ISSN 2056-306X. PMC 6330759. PMID 30656061.
  2. Kronmüller, Christian; Lewis, John G. J. (2015-06-30). "On the function of the ultimate legs of some Scolopendridae (Chilopoda, Scolopendromorpha)". ZooKeys. 510: 269–278. doi:10.3897/zookeys.510.8674. ISSN 1313-2970. PMC 4523778.
  3. Kenning, Matthes; Müller, Carsten H. G.; Sombke, Andy (2017-11-14). "The ultimate legs of Chilopoda (Myriapoda): a review on their morphological disparity and functional variability". PeerJ. 5: e4023. doi:10.7717/peerj.4023. ISSN 2167-8359. PMC 5691793.
  4. Sombke, Andy; Müller, Carsten H. G. (Apr 2021). "When SEM becomes a deceptive tool of analysis: the unexpected discovery of epidermal glands with stalked ducts on the ultimate legs of geophilomorph centipedes". Frontiers in Zoology. 18 (1): 17. doi:10.1186/s12983-021-00402-3. ISSN 1742-9994. PMC 8056527. PMID 33879192.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.