Schroederichthys chilensisRed-spotted cat shark

Geographic Range

Redspotted catsharks inhabit coastal waters ranging from central Peru to southern Chile in the eastern Pacific Ocean. (Farina and Ojeda, 1993)

Habitat

Redspotted catsharks are found from the rocky sublittoral areas to the border of the continental shelf. Their distribution appears to be seasonal, in the rocky subtidal areas in spring, summer, and fall, and spending winter in deeper offshore waters. This is believed to be because of strong currents and tubulence that occurs during winter. Redspotted catsharks are typically only found in waters ranging from one to fifty meters in depth. (Aedo and Arancibia, 2001; Farina and Ojeda, 1993)

  • Range depth
    1 to 50 m
    3.28 to 164.04 ft

Physical Description

Redspotted catsharks have sleek elongate bodies typical of their family. They have five gill slits, with the fifth gill opening over the origin of the pectoral fin. They have two dorsal fins, without spines, and the first dorsal axil is over the pelvic origin. Their tail has almost no upward bend.

Redspotted catsharks are typically dark reddish brown on the dorsal side and a creamy white on the ventral side. They have dark saddles down their sides and dark red spots on the white portion of their body.

Their teeth are typically multicuspid and males often have longer teeth with fewer cusps, which is believed to aid in 'courtship biting'.

Captured redspotted catsharks have ranged in length from 30cm to 66cm. However, it is believed that they can grow to be larger than this. ("Clase Elasmobranchii", 2004; Carpenter and Luna, 2004; Farina and Ojeda, 1993; Morillas, et al., 1987; Nelson, 1984; Smith and Heemstra, 1986; Smith, 1949)

  • Sexual Dimorphism
  • male larger
  • Range length
    30 to 66 cm
    11.81 to 25.98 in

Development

Redspotted catsharks are born from encapsulated eggs that are fertilized and released into the water. When they hatch, they are miniature versions of adults. It is believed that juveniles swim into deeper waters in order to avoid predation in the sublittoral zone that they return to when they are adults. Therefore, there is a spatial segregation between adult and juvenile populations. Redspotted catsharks grow rapidly, however, their maturation age is currently unknown. (Budker, 1971; Farina and Ojeda, 1993; Budker, 1971; Farina and Ojeda, 1993)

Reproduction

It is believed that redspotted catsharks mate relatively seasonally. However, there have been instances where female sharks have been found with encapsulated eggs throughout the entire year. They are polygynandrous and have a courtship ritual in which the male will bite the female while he fertilizes her eggs. (Carpenter and Luna, 2004; Farina and Ojeda, 1993)

Redspotted catsharks are oviparous. Breeding occurs in individuals in an annual cycle. Females have been shown to have egg capsules in the winter, spring, and summer, but very rarely in the fall. Reproduction occurs through the fertilization of the egg while it is still inside the female. The egg is then encapsulated and released. There are typically two eggs in each capsule. Embryos feed on the yolk of the egg until they hatch. When they hatch they head for deeper water until they are adults. (Budker, 1971; Carpenter and Luna, 2004; Farina and Ojeda, 1993; Ommanney, 1964)

  • Breeding interval
    Redspotted catsharks breed annually
  • Breeding season
    Fertilization occurs in spring and winter, but is most common in summer
  • Range number of offspring
    1 to 2
  • Average number of offspring
    1

Fertilized eggs are released into the water and the embryos feed on the egg yolk. Once the female lays her eggs, there is no subsequent parental investment. (Carpenter and Luna, 2004)

  • Parental Investment
  • pre-fertilization
    • provisioning
    • protecting
      • female

Lifespan/Longevity

The lifespan of redspotted catsharks is currently unknown.

Behavior

Redspotted catsharks are a solitary species. They are nocturnal, staying in caves and crevices during the day and emerging at night to feed. They migrate during the winter months to deeper waters than they live in during the rest of the year, typically moving toward the edge of the continental shelf. This is believed to be due to the stronger currents that occcur at this time of year. (Aedo and Arancibia, 2001; Farina and Ojeda, 1993)

Communication and Perception

Communication specific to the redspotted catshark is unknown. However, as with most other sharks, including those in the family Scyliorhinidae, it is believed that they have a well developed sense of smell, and that they are electroreceptive. All sharks are more sensitive to electricity than many other organisms. This allows them to detect electricity emitted by other animals, and may also allow them to detect magnetic fields, which aides in navigation.

Catsharks are named for the catlike vertical oval pupil of their eyes. Their vision is good in dim light. ("Shark Senses", 1999; Ommanney, 1964)

Food Habits

Redspotted catsharks are predators that feed on a variety of small vertabrates and invertabrates. Their primary food source includes crabs (Allopetrolisthes punctatus, and Petrolisthes violaceus) and rock shrimp (Rhynchocinetes typus). They have also been known to eat several other species of crustaceans, as well as fishes, algal material, and various polychaetes. (Aedo and Arancibia, 2001; Carpenter and Luna, 2004; Farina and Ojeda, 1993)

  • Primary Diet
  • carnivore
    • eats non-insect arthropods
  • Animal Foods
  • fish
  • aquatic or marine worms
  • aquatic crustaceans
  • Plant Foods
  • algae

Predation

It is believed that redspotted catshark juveniles move to deeper coastal waters until they develop into adults to avoid predation in the subtidal areas. However, the actual predators of this species are unknown. (Farina and Ojeda, 1993)

Ecosystem Roles

Redspotted catsharks are an important predator in their ecosystem. Their particular influence in the near shore environment is on the commercial benthic populations.

They are hosts to several parasites, including the leech, Branchellion ravenellii. These leeches are believed to pass trypanosomes (Trypanosoma scyllii) into the redspotted catsharks' bloodstream. The trypanosomes also use the redspotted catshark as their host. (Farina and Ojeda, 1993; Morillas, et al., 1987)

Commensal/Parasitic Species
  • a leech Branchellion ravenellii
  • a trypanosome Trypanosoma scyllii

Economic Importance for Humans: Positive

Research and Education of redspotted catsharks are the only positive economic importance for humans. (Budker, 1971)

  • Positive Impacts
  • research and education

Economic Importance for Humans: Negative

Redspotted catsharks can be a detriment to commercial fisheries in Chile and Peru. They feed on crustaceans that are a large economic source in the area. (Farina and Ojeda, 1993)

Conservation Status

Redspotted catsharks are not listed on the ICUN Red List, the U.S. Federal List, or the CITES list. It is not known to be a vulnerable or threatened species.

Contributors

George Hammond (editor), Animal Diversity Web.

Valerie Ackley (author), University of Michigan-Ann Arbor, William Fink (editor, instructor), University of Michigan-Ann Arbor.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

coastal

the nearshore aquatic habitats near a coast, or shoreline.

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

electric

uses electric signals to communicate

fertilization

union of egg and spermatozoan

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

internal fertilization

fertilization takes place within the female's body

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

migratory

makes seasonal movements between breeding and wintering grounds

motile

having the capacity to move from one place to another.

natatorial

specialized for swimming

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

saltwater or marine

mainly lives in oceans, seas, or other bodies of salt water.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

References

2004. "Clase Elasmobranchii" (On-line). Accessed October 29, 2004 at http://www.biouls.cl/biozoo/Vertebra/sispez2.htm.

Enchanted Learning. 1999. "Shark Senses" (On-line). Accessed November 10, 2004 at http://www.enchantedlearning.com/subjects/sharks/anatomy/Senses.shtml.

Aedo, G., H. Arancibia. 2001. Gastric evacuation of the redspotted catshark under laboratory conditions. Journal of Fish Biology, 58: 1454-1457.

Budker, P. 1971. The Life of Sharks. New York: Columbia University Press.

Carpenter, K., S. Luna. 2004. "Schroederichthys chilensis Redspotted Catshark" (On-line). Accessed October 29, 2004 at http://filaman.uni-kiel.de/summary/SpeciesSummary.cfm?id=839.

Farina, J., F. Ojeda. 1993. Abundance, activity, and trophic patterns of the redspotted catshark, Schroederichthys chilensis, on the Pacific temperate coast of Chile. Copeia, 2: 545-549.

Morillas, J., M. George-Nascimento, H. Valeria, R. Khan. 1987. Trypanosoma humboldti n. sp. from the Chilean Catshark, Schoroederichthys chilensis. Journal of Protozoology, 34/3: 342-344.

Nelson, J. 1984. Fishes of the World. New York: John Wiley and Sons.

Ommanney, F. 1964. The Fishes. New York: Time Incorporated.

Smith, J. 1949. The Sea Fishes of Southern Africa. South Africa: Central News Agency LTD..

Smith, M., P. Heemstra. 1986. Smiths' Sea Fishes. South Africa: L. L. B. Smith Institute of Ichthyology.