Chiloscyllium

Diversity

Chiloscyllium species, or the carpet or bamboo sharks, belong to the family Hemiscylliidae . There are seven described species and each can be characterized by their subterminal nostrils, thin pectoral and pelvic fins, and cylindrical body. Dark spots or pigmentation can be seen in juveniles but fade as they reach maturity. Their size and adaptability make them popular aquarium attractions.

Geographic Range

Chiloscyllium species span from the Arabian Sea to the northwest Pacific, including the Indo-Malay archipelago and Papua New Guinea. The majority of species are found in the Indo-West Pacific. These are their native ranges, but they can be found in many aquariums across the world as well.

• Biogeographic Regions
• oriental oriental
  • native native
• indian ocean
  • native native
• pacific ocean pacific ocean
  • native native

Habitat

Bamboo and carpet sharks can either be found gliding on the benthic seafloor or resting in coral reefs. They can be found anywhere between 0m-85m in depth and prefer sandy, muddy, and rocky environments. Brown-banded bamboo sharks can sometimes be found in tide pools, as they are capable of handling that environment for a lengthy amount of time. They are most active at night time when hunting for food.

• Habitat Regions
• tropical tropical
• saltwater or marine saltwater or marine

• Aquatic Biomes
• benthic benthic
• reef reef

Systematic and Taxonomic History

Phylogenetic relationships between sharks are hard to describe because researchers cannot always track their movements due to their natural environment. Researchers also do not know where sharks give birth and/or mate, so trying to track down families to determine relationships is difficult as well.

Initially, the genus Chiloscyllium was determined primarily based on morphological features. Body color, position of fins, and body-to-tail ratios were used to categorize shark species within Chiloscyllium . Throughout the years, there have been many discussions on the relationship between the species of this genus, specifically between C. indicum and C. punctatum .

Physical Description

Chiloscyllium sharks' bodies are elongated with brown bands appearing on most. Generally, the brown bands fade as the sharks mature; but in some cases, like with white spotted bamboo sharks, they do not. Large spiracles are located below and behind the eyes, which rest on either the side of the sharks' heads. Their mouths are located closer to their eyes than their mouths, which are rounded and transverse with small, blunt teeth. Their dorsal fins are equal in size while their pectoral are straight with broad tips. They also have lobbed fins and their dorsal region has no spine.

• Other Physical Features
• ectothermic ectothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• female larger

Development

Chiloscyllium sharks are oviparous, which means they lay eggs instead of giving live birth. They release their eggs on the benthic seafloor. Fine tendrils on the eggs allow them to attach to coral or rocks. The embryos feed solely on the yolk inside of the egg until they hatch. Once they hatch, they are free swimming. If in captivity, it can take up to 4 months for the embryo to hatch. Some species have been known to utilize either parthogenesis or sperm storage techniques when contact with males is scarce. One species' female was documented to have stored sperm for 45 months. If parthogenesis is used, the zygote is diploid, wherein the ovum fuses with a polar body and the allelic diversity is very low.

Reproduction

Like most sharks, not much is known about Chiloscylluim species' mating systems because they are rarely seen. Since this genus is popular in aquarium settings, it is easier to see mating in captivity, but many of them are the same sex or different species altogether. What is known is that males will bite the pectoral fin of females for about a half an hour while swimming in order to initiate mating. Copulation duration averages five minutes. There are many records of Chiloscylluim sharks going back to the same mating spots multiple times.

• Mating System
• polygynandrous (promiscuous) polygynandrous (promiscuous)

Most sharks' mating sites, birth places, and hatching sites are not known. Chiloscyllium species usually lay their eggs in pairs for 6-7 days over 2-3 months. This generally occurs during late July to February. The female can usually lay around 15-20 eggs. Female and male sharks are only seen together during mating. Females mature around a body length of 63cm whereas males mature around a body length of 68-76cm.

• Key Reproductive Features
• parthenogenic parthenogenic
• sexual sexual
• fertilization fertilization
  • internal internal
• oviparous oviparous

Chiloscyllium species lay eggs. There is little to no parental involvement. However, currently no one has been able to document these sharks' exact hatching spots, nor where they lay their eggs.

• Parental Investment
• no parental involvement

Lifespan/Longevity

In the wild, Chiloscyllium individuals can live anywhere from 12-14 years. However, they have been known to live up to 25 years in captivity.

Behavior

Many species of Chiloscyllium , such as the gray bamboo shark, are rarely seen because they are solitary and nocturnal sharks. Because of their size, these sharks can hide in coral reefs or caverns during the day and hunt at night. When they are active, they are usually found swimming along the floor of the ocean. They stay close to shores and do not migrate. Many behaviors that researchers have been able to observe/study have occurred in aquariums because of Chiloscyllium sharks' popularity in the business.

• Key Behaviors
• natatorial natatorial
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• solitary solitary

Communication and Perception

Solitary animals like those within Chiloscyllium make it challenging to gather data on communication techniques. However, researchers have found that the sharks' sense of sight is minimally used while the detection of smells, vibrations, and electrical stimuli is the sharks' main way to perceive their environment and communicate.

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical
• electric electric

• Other Communication Modes
• vibrations vibrations

• Perception Channels
• acoustic acoustic
• vibrations vibrations
• chemical chemical
• electric electric

Food Habits

Chiloscyllium sharks hunt and feed during the night, and their diet consists of smaller fish, crabs, shrimp and/or other invertebrates found on the ocean floor. The sharks locate their prey via electroreceptors known as ampulae of Lorenzini. Their blunt teeth allow them to hold onto soft prey without shredding flesh. The arrangement of these sharks' teeth and jaw aid in catching hard-bodied prey as well.

• Primary Diet
• carnivore carnivore
  • piscivore piscivore
  • eats non-insect arthropods

Predation

Smaller sharks like those in Chiloscyllium are usually prey for larger sharks and/or other large marine mammals. Because of their size, Chiloscyllium sharks can easily hide in crevices and coral reefs. The Chiloscyllium species that keep their brown band coloration as adults can camouflage into those areas especially well.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Sharks are oftentimes apex predators and keystone species in their environments, and Chiloscyllium species are no different. Their ecological roles mostly consist of eating smaller organisms or hosting parasites.

• Ecosystem Impact
• keystone species keystone species

Economic Importance for Humans: Positive

Chiloscyllium species are hunted for meat, thus they are a significant trade in commercial fishery industries. But these sharks primarily have high demand in personal and public aquariums because of their small sizes, adaptabilities, and appearances. They are also capable of reproducing in captivity, another desirable trait for aquarium enthusiasts. They can also sometimes be used in Chinese medicinal techniques.

• Positive Impacts
• pet trade pet trade
• food food
• source of medicine or drug source of medicine or drug

Economic Importance for Humans: Negative

There are no documented negative effects of Chiloscyllium on humans.

Conservation Status

Since there is insufficient data/research regarding Chiloscyllium sharks, they are not listed as Vulnerable on the IUCN Red List, but rather "Near Threatened." Additionally, commercial fishing is not the only component threatening these shark species; habitat degradation is a key factor as well. There are measures being taken to help the species, albeit not direct aid. There are 51 protected marine areas throughout Malaysia, all in which Chiloscyllium species can reside and/or seek protection in. Additionally, Thailand does not allow large vessels (over 10 gross tonnage) within two nautical miles of shore, and Taiwan prohibits net fishing in numerous coral reefs.

Additional Links

Encyclopedia of Life

Contributors

harli soura (author), Colorado State University, Audrey Bowman (editor), Colorado State University, Sydney Collins (editor), Colorado State University.

References

Bernal, M., N. Sinai, C. Rocha, M. Gaither, F. Dunker, L. Rocha. 2015. Long-term Sperm Storage in the Brown banded Bamboo Shark Chiloscyllium punctatum. Journal of Fish Biology , 86: 1171-1176. Accessed February 03, 2022 at https://onlinelibrary-wiley-com.ezproxy2.library.colostate.edu/doi/pdf/10.1111/jfb.12606 .

Bester, C. 2022. "Chiloscyllium puncatatum" (On-line). Florida Museum. Accessed March 04, 2022 at https://www.floridamuseum.ufl.edu/discover-fish/species-profiles/chiloscyllium-punctatum/ .

Carroll, C., S. Young. 2017. "Grey Bamboo Shark" (On-line). The Wonderful Wildlife Of Samleon. Accessed March 04, 2022 at https://thewonderfulwildlifeofsamloem.wordpress.com/2017/09/27/grey-bamboo-shark-chiloscyllium-griseum/ .

Harahush, B., A. Fischer, S. Collin. 2007. Captive Breeding and Embryonic Development of Chiloscyllium punctatum. Journal of Fish Biology , 71: 1007 - 1022. Accessed February 03, 2022 at https://onlinelibrary-wiley-com.ezproxy2.library.colostate.edu/doi/pdf/10.1111/j.1095-8649.2007.01569.x .

Kyne, P., A. Bin Ali, F. Fahmi, K. Herman, B. Manjaji Matsumoto, W. Vanderwright. 2021. "Whitespotted Bambooshark" (On-line). ICUN Red list (online). Accessed March 04, 2022 at https://www.iucnredlist.org/species/124554059/124453319#geographic-range .

Masstor, N., A. Samat, S. Nor, B. Zain. 2014. Molecular Phylogeny of the Bamboo Sharks. BioMed Research International , 2014: 1-9. Accessed February 03, 2022 at https://downloads.hindawi.com/journals/bmri/2014/213896.pdf .

Wu, T. 2014. "Whitespotted Bamboo Shark Mating" (On-line). Tony Wu. Photo-Naturalist. Accessed March 04, 2022 at http://www.tonywublog.com/journal/whitespotted-bamboo-shark-mating-chiloscyllium-plagiosum .

Wyffels, J., L. Adams, F. Bulman, A. Fustukjian, M. Hyatt, K. Feldheim, L. Penfold. 2021. Artifical Insemination and Parthenogenesis in the Whitespotted Bamboo Shark. Scientific Reports , 11: 1-12. Accessed February 11, 2022 at https://www.nature.com/articles/s41598-021-88568-y.pdf .

2021. "Bamboo Sharks" (On-line). Accessed March 04, 2022 at https://inaturalist.ca/taxa/87416-Chiloscyllium .

2015. "Genus: Chiloscyllium, Bamboo Sharks, Shark-bamboo" (On-line). Smithsonian Tropical Research Institute. Accessed March 04, 2022 at https://biogeodb.stri.si.edu/caribbean/en/thefishes/taxon/5755 .

2017. "Shark Communication" (On-line). Sharks-World. Accessed March 04, 2022 at https://www.sharks-world.com/shark_communication/ .

2021. "Species Profile: The Whitespotted Bamboo Shark" (On-line). We Love Sharks. Accessed March 04, 2022 at https://welovesharks.club/species-profile-the-whitespotted-bamboo-shark/ .

2015. "Whitespotted Bamboo Shark" (On-line). Accessed March 04, 2022 at https://singapore.biodiversity.online/taxo4254/mainSpace/Whitespotted%20Bamboo%20Shark.html .