REDSPOTTED CATSHARK

Taxonomy:

Phylum– Chordata

Class– Chondrichthyles

Order– Carcharhiniformes

Common Name– Ground Sharks

Family– Scyliorhinidae

Common Name– Catsharks

Genus– Schroederichthys

Species– chilensis

Status: IUCN Red List DATA DEFICIENT

Average Size and Length: The length of hatchlings is unknown. Adult males have been measured between 56-62 cm/1.8-2 feet. The maximum recorded has been 2 feet long, but currently there are reports of sharks reaching 66 cm/2.2 feet or greater.

Teeth and Jaw: The mouth is very broad and wide. Redspotted catsharks have multicuspid teeth. Sexual dimorphism is evident in dentition of male species. Males typically have longer teeth with fewer cusps. This is believed to aid in courtship biting. The teeth are sharp, triangular, somewhat long and pointed that appear to be a single cusp because the two cusplets surrounding the main cusp are almost not visible to the naked human eye.

Head: The snout is short, broad and rounded. The anterior nasal flaps are broad and triangular in shape.

Tail: The tail is short.

Demographic, Distribution, Habitat, Environment and Range: The Redspotted catshark can be found in the southeast Pacific in South America off Peru and south-central Chile (9°S – 51°S). They can be found in temperate inshore waters on the continental shelf, on or near the bottom. They are typically found in the rocky sublittoral areas down to 328 feet, considered to be subtropical demersal. They are sometimes found in very shallow, inshore water between 1-164 feet. The Redspotted catshark spends the spring, summer, and fall in rocky subtidal areas, but winter in deeper offshore waters due to the strong currents at that time of year.

Diet: Redspotted catsharks feed on organisms that dwell on the rocky bottom near the continental shelf. Their primary food sources are various species of crabs and the rhynchocinetid rock shrimp Rhynchocinetes typus (Farina and Ojeda 1993). They have also been known to eat fishes, algal material, and various polychaetes.

Juveniles typically spend their early life in the deeper offshore waters. This is believed to be to avoid predators, although what those predators are is unknown.

Aesthetic Identification: The Redspotted catshark has a moderately slim body. Their dorsal side is a dark reddish brown with conspicuous dark saddles including two in the interdorsal space, many dark spots that do not border the saddles, and have few white spots or none at all. Their ventral sides are a creamy white with reddish spots. The origin of the first dorsal fin is lightly in front of the pelvic fin insertions. The young are slenderer than the adults.

Biology and Reproduction: They are oviparous, and probably lay pairs of eggs, one egg per oviduct. There are tendrils on each egg case that allow the female to secure the egg cases to the sea bed.

They typically mate seasonally, in spring and winter, though females have occasionally been shown to have egg capsules in the summer. They are polygynandrous and while the male fertilizes the female’s eggs, he typically performs what is called a “courtship ritual” that consists of the male biting the female.

Redspotted catsharks are host to trypanosomes, parasites that are passed into the catsharks’ bloodstream through leeches.

Behavioral Traits, Sensing and Intelligence: Redspotted catsharks are believed to be solitary, nocturnal animals. They possibly stay in caves and crevices during the day and emerge at night to feed. They are a migratory species.

It is believed that the Redspotted catshark, like other sharks, have a well-developed sense of smell, and that they are electroreceptive, which allows them to detect electricity emitted by other animals, and may also allow them to detect magnetic fields, which aids in navigation.

Speed: They are thought to be slow-moving.

Redspotted Catshark Future and Conservation: There is not enough data to evaluate. They do appear to be quite common among their range. Redspotted catsharks are an important predator within their ecosystem. They have a large influence on commercially fished benthic organisms that dwell in the rocky near-shore areas. Catsharks in general are also a frequent bycatch of nearshore fishing trawlers, which, while not economically significant, can cause damage to nets as well as time lost in removing the bycatch from the viable catch.

Redspotted Catshark Recorded Attacks on Humans: Not a threat to humans.