Lobster Mandibles
On the Functional Morphology of Decapod Mouthparts and Appendages used for Grooming
Abstract
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Decapods are aquatic organisms that usually have five pairs of walking legs. Examples of decapods include, but are not limited to, lobsters, crabs, and shrimp. They are mainly predators and scavengers. In order to accomplish this way of life, they must have a variety of mouthparts. The most anterior mouthparts such as the chelipeds, third maxillipeds, and second maxillipeds are used to capture prey and tear apart large pieces of food. Appendages closer to the mouth are mainly used to separate food from substrates and stabilize food so that the mandibles may shred it.
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Cleaning and grooming is a well-developed characteristic of all Decapod species. Some clean more than others while others may use different appendages for cleaning different parts of their bodies. The majority of Decapods use only two appendages for cleaning: the third maxillipeds and the fifth pereiopods. The third maxillipeds clean the head region as well as the second, third, and fourth pereiopods. The fifth pereiopods clean areas where the third maxillipeds cannot reach. The mouthparts
The Chelipeds The chelipeds are the first pair of walking legs. The whole appendage is enlarged with special attention to the chelae, or claw, as seen in Fig. 1. Among its functions, the chelae give the organism a great advantage for capturing small prey. It also has numerous sensory setae, which help detect detritus on the ocean floor as well as locating other objects (Schembri, 1983). When food is found, the chelae grab it or scoop it up to the third maxillipeds (Kunze and Anderson, 2006).
Fig 1-. Cheliped. The chelae is very enlarged which helps to capture prey (Livingstone, 1996). Third Maxillipeds The third maxillipeds are the biggest, most anterior, and most flexible of the mouth appendages.
Abstract
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Decapods are aquatic organisms that usually have five pairs of walking legs. Examples of decapods include, but are not limited to, lobsters, crabs, and shrimp. They are mainly predators and scavengers. In order to accomplish this way of life, they must have a variety of mouthparts. The most anterior mouthparts such as the chelipeds, third maxillipeds, and second maxillipeds are used to capture prey and tear apart large pieces of food. Appendages closer to the mouth are mainly used to separate food from substrates and stabilize food so that the mandibles may shred it.
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Cleaning and grooming is a well-developed characteristic of all Decapod species. Some clean more than others while others may use different appendages for cleaning different parts of their bodies. The majority of Decapods use only two appendages for cleaning: the third maxillipeds and the fifth pereiopods. The third maxillipeds clean the head region as well as the second, third, and fourth pereiopods. The fifth pereiopods clean areas where the third maxillipeds cannot reach. The mouthparts
The Chelipeds The chelipeds are the first pair of walking legs. The whole appendage is enlarged with special attention to the chelae, or claw, as seen in Fig. 1. Among its functions, the chelae give the organism a great advantage for capturing small prey. It also has numerous sensory setae, which help detect detritus on the ocean floor as well as locating other objects (Schembri, 1983). When food is found, the chelae grab it or scoop it up to the third maxillipeds (Kunze and Anderson, 2006).
Fig 1-. Cheliped. The chelae is very enlarged which helps to capture prey (Livingstone, 1996). Third Maxillipeds The third maxillipeds are the biggest, most anterior, and most flexible of the mouth appendages.
Cited: Bauer, R. T. 1977. “Antifouling Adaptation of Marine Shrimp (Crustacea: Decapoda: Caridae): Functional Morphology and Adaptive Significance of Antennular Preenign by the Third Maxillipeds.” Marine Biology. 261: 261-276. I Bauer, Raymond T. 1989. “Decapod crustacean grooming: Functional morphology, adaptive value, and phylogenetic significance.” Journal of Crustacean Biology. 1(2): 153-173. Farmer, A. S. 2007. “The functional morphology of the mouthparts and pereiopods of Nephrops norvegicus (L.) (Decapoda: Nephropidae).” Journal of Natural History. 8(2): 121-142. Felgenhauer, Bruce E Livingstone. 1996. First Maxillae. Picture. http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=CRUS023B&File_type=GIF. Livingstone. 1996. First Maxilliped. Picture. http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=CRUS019B&File_type=GIF. Livingstone. 1996. Mandible. Picture. http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=CRUS024B&File_type=GIF. Livingstone. 1996. Second Maxillae. Picture. http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=CRUS020B&File_type=GIF. Livingstone. 1996. Second Maxilliped. Picture. http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=CRUS018B&File_type=GIF. Livingstone. 1996. Third Maxilliped. Picture. http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=CRUS017B&File_type=GIF. Martin, J. W. and B. E. Felgenhauer. 2011. “Grooming behaviour and the morphology of grooming appendages in the endemic South American crab genus Aegla (Decapoda, Anomura, Aeglidae).” Journal of Zoology. 209(2): 213-224. Schembri, Patrick J. 1982. “Functional Morphology of the Mouthparts and Associated Structures of Pagurus rubricatus (Crustacea: Decapoda: Anomura) with Special Reference to Feeding and Grooming.” Zoomorphology. 101:17-38. Schembri, Patrick J