Stegostoma varium STEVAR-042099-CARMIT-001

This entry was posted on Tuesday, April 20th, 1999 and is filed under Sharks, Spawning Reports.

The Breeder’s Registry® Information contained in this report is taken from submitted observations from aquarist unless noted otherwise (see comments). Information may be reproduced providing the Breeder’s Registry is cited.


Breeder ID: STEVAR-042099-CARMIT-001

Date received: 4/20/99

Identification: Stegostoma varium Garmen, 1913

Origin: Indo-Pacific – Samoa to Australia, north to Japan, Indonesia to South Africa, Red Sea


Taxonomy: (after I.C.Z.N.)

Kingdom Animalia

Phylum Chordata Subphylum Vertebrata

Class Chondrichthyes Subclass Elasmobranchii Superorder Selachimorpha

Order Orectolobiformes

Family Stegostomatidae

Genus Stegostoma Müller & Henlee, 1837

Species varium Garmen, 1913


Description: The Family Stegostomatidae are commonly referred to as zebra sharks and contains 13 species made up of 3 genus; Squalus (8), Stegostoma (3) and Scyllium (1). Stegostoma varium is characterized by the heterocercal tail almost as long as its body,a small mouth and ridges along the sides of the body. Juvenile appearance is banded while adults are spotted. Coloration varies yellow stripes and spots on a brown body , to dark spots on a yellow to cream body. Reported maximum size to 230 cm.


Length of time in captivity – male (yr): ~ 3 years

Size male: ~182 – 198 cm ( ~ 6 – 6.5 ft)

Length of time in captivity – female (yr): ~ 3 years

Size female: 182 cm (182 cm)

Physical differences: Clasper on male, female with many bites on pectoral and caudal fin.

Adult diet: Mackeral, squid, Bonita- target feed 2 times per week. Tank “fed” everyday so they do get food from broadcast feedings. Vitamins once per week.

Pre-spawning activity: Male grabs females pectoral or caudal fin. Female will immediately stop swimming and crash to the bottom substrate. Sometimes she will roll over, other times they will sit there for hours with the male having the females fin in his mouth.

Time spawning began: Usually morning to mid-afternoon.

Area spawning occurred: On the bottom

Frequency of spawning: Spawning behavior is quite frequent, mating actually only witnessed a few times.

Egg description: Eggs are ~12 – 18 cm long ( ~ 5 – 7 inches), and ~10 – 15 cm (4 – 6 inches) tall

Approximate quantity: 44 eggs. 7 were fertile

Egg changes / development: Some eggs lost right after they would open the egg slit. Increased flow in holding tank to help circulation through eggs. After this was done, no more eggs were lost. Holding tank was hooked up to display tank so water quality was constant which is crucial.

Gestation period: 6.5 months

Time hatching occurred: overnight

Size of hatching larvae: ~ 22 cm ( 9 inches)

Yolk sac present? not indicated

Newly hatched appearance: Dark coloration with yellow stripes. Large head, extremely long tail.

Transfer / removal method: Carefully removed tendrils from artificial coral and placed in 5 gallon bucket and taken to the surface. Moved to holding tank.


Spawning tank size (liter): 3.4M liters (900,000 gallons). ~17 – 20 meters L x 28 meters W x 4.5 meters D. (70 – 80′ x 100′ x 18′)

Sides of tank covered? Back, black

Lighting & photoperiod: many 400 watt metal halides 12 hours approximately 1.5 meters from surface (6 feet).

Filtration: Rapid sand filtration, ozone, high pumping volume. ASW (made on premises). Water changes 4 times weekly ~ 95,000 liters (25,000 gallons). Water that is removed is cleaned up (no details given) and reused. Evaporation replacement water is reverse osmosis treated tap water.

Additives and dosages: Shark vitamins to adults once per week.

Water temperature (F): 76 – 77 deg with 1 deg F fluctuation

Salinity: 33 – 34 ppt

pH: 8.0 – 8.2

Nitrate: 60 – 80 ppm


Fry development / changes: Young will spend more time in the lighted section of the tank.

Diet: chunked smelt, squid and clams. Fed with a feeding pole ( 3/16″ rigid tubing) 3 x per day.

Survival: as of April 19, 1999, 2 of 7 fertile eggs have hatched. 5 eggs remain to hatch.


Rearing tank size (liter): Connected to main display. 180 cm L x 45 cm W x 45 cm H (72″ x 18″ x 18″)

Sides of tank covered? no

Filtration: connected to display. see above.


Comments:

Original description: S. Garmen is the acknowledged author in 1913 (September) 1913:59 Mem. Mus. Comp. Zool. v36, The Plagiostoma (sharks, skates, and rays). It was not intended as a new type, but apparently validates a name appearing in a non-binomial work (Squalus varius Seba, 1759 ) which is a valid species. Garmin is listed as the naming author in Catalog of Fishes, 1998, Vol 2:1745 and Vol 3:2177. The references to this species are somewhat confusing. Garmin produced a number of papers from 1875 – 1913.

Synonyms: Stegostoma faciatum Hermann 1783 which was also based on Squalus varius of Seba 1759. Herman is acknowledged as the author Squalus faciatus in 1783

Vernacular name: Zebra shark (USA), Leopard shark (Australia)

Word origin: The genus Stegostoma is from the Greek root(s) stego meaning covered; and stoma meaning mouth. The genus varium is from the Latin root(s) vari- meaning varigated or mottled.

Suggested reading:

Michael, S. W., Reef Sharks and Rays. Sea Challengers, ISBN 0-930118-18-9

Burgess, W. E., Axelrod, H. R. & Hunziker, III, R. E., Atlas of Marine Aquarium Fishes, Second Edition, 1990, T. F. H. Publications, One T. T. H. Plaza, Neptune City, NJ 07753, TFH-H-1100, ISBN 0-86622-896-9 (color illustration, page 34, size comparison chart to other sharks, page 40).

About this report: Information contained in this report is taken from submitted observations. Taxonomy, Synonomy, Original description , Word origin and Suggested reading are provided by member(s) of The Breeder’s Registry staff. Information is presented under the belief that it is accurate. If you have information in addition to, or contrary to that presented you are encouraged to contact the Breeder’s Registry. Permission is granted for “one-time” personal use. Reproduction as distributed or accessible media is prohibited without prior written permission. All rights reserved. 1999

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