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.

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Breeder ID: OCTBRI-022895-WOOJAM-001

Date: 2/28/95

Identification: Octopus briareus Robson, 1929

Geographic origin: Caribbean

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Taxonomy: (after I.C.Z.N.)

Kingdom: Animalia

Phylum: Mollusca

Class: Cephalopoda

Order: Octopoda

Family: Octopodidae

Genus: Octopus

Subgenus: Octopus

Species: briareus

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Description: Brown to iridescent green to red in color. Arms are long and thin in relation to body, second and third pair of arms are longer than others. Reaches a length up to 54 cm.

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Life span (year): 1

Size (mm): varies for male and female

Physical differences: Male octopus have a modified third right arm or hectocotylus that is used for spermatophore transfer.

Adult diet: Live crustaceans, (crabs, shrimp). Live freshwater fish and frozen shrimp used when live crustaceans unavailable. Fed every other day.

Pre-spawning activity: One of the females “redecorated” the tank by moving all the rocks around three (3) days prior to laying eggs.

Time spawning began: night

Area spawning occurred: On glass, upper corner

Frequency of spawning: Only once

Egg description: Eggs attached in strings. Several in each “festoon”

Approximate quantity: 200+

Size: ~ 12 mm

Egg changes / development: When octopus and yolk “flip” in egg incubation is 75% complete.

Incubation period: 41 – 88 days

Time hatching occurred: night

Newly hatched appearance: Small versions of parent. Fully developed. Capable of inking and pulsing chromatophores.

Size at hatching: 15 mm TL

Yolk sac present? No

Transfer / removal method: Half were removed to an environmental chamber at 20 C, suspended from glass slides. Half left with mother at 25 – 26 C. Removed eggs took twice as long to hatch.

Fry development / changes: Arms appear to grow faster than mantle. Mantle is ~ 30 – 40% of total length (TL) at hatching.

First food offered: Mysid shrimp. DO NOT USE ARTEMIA!

Second food offered: Amphipods offered for variety.

Survival: 50% first week. Only 2 by second week. Long term survival 6 weeks. Lost due to aeration failure.

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Spawning tank size (liter): 75

Sides of tank covered? Yes, black

Lighting & photo-period: Minimal and variable

Filtration: Wet / dry, skimmer, natural seawater

Additives and dosages: none

Water temperature (F): 78

Specific gravity: 1.023

pH: not indicated

Nitrate: not indicated

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Rearing tank size (liter): 3.75

Sides of tank covered? No

Lighting & photo-period: 2 Minimal and variable

Filtration: Undergravel filter, Hagen 200® powerfilter, skimmer

Additives and dosages: Aeration only

Water temperature (F): 68

Specific gravity: 1.023

pH: not indicated

Nitrate: not indicated

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Comments: Female refuses to eat after laying eggs and dies shortly after hatching of eggs. Females will lay unfertilized eggs.

Word origin: Octopus is from the Latin root oct, -i, -o, meaning eight (8) and -pus from the Greek root meaning foot. The genus briareus has no Latin or Greek word or root origins and may be named for an individual.

Vernacular name: Reef Octopus, Briar Octopus

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