Notoacmea digitalis NOTDIG-092694-SHIRON-002

This entry was posted on Monday, September 26th, 1994 and is filed under Slugs and snails, 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: NOTDIG-092694-SHIRON-002

Date received: 9/26/94

Identification: Notoacmea digitalis (?)

Geographic origin: Pudget Sound

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

Kingdom Animalia

Phylum Mollusca


Class Gastropoda Subclass Prosobranchia

Order Archeogastropoda Superfamily Pleurotomariacea

Family Notoacmaeidae

Genus Notoacmaea

Species digitalis

Duration male(yr): 5.0

Size male (mm): 20

Duration female 1 (yr): 5.0

Size female 1 (mm): 20

Broodstock notes: Originally collected from rocky shores, San Juan Island, Washington

Physical differences: None

Adult diet: Diatoms on rock surfaces

Pre-spawning activity: Maintain animals at ~47 F overnight. Place in bowl of fresh seawater and allow to come to ~ 70 F. Animals generally spawn. Eggs fertilized by placing sperm suspension with eggs.

Time spawning began: induced

Area spawning occurred: not particular

Frequency of spawning: weekly during spring

Egg description: Eggs, cloudy; Sperm “smokey poof”

Approximate quantity: 1000

Size: 160 micron

Egg changes / development: Fertilized eggs rinsed using 100 micron nitrex screen with seawater.

Incubation period: none (?)

Time hatching occurred: n/a

Newly hatched appearance: Trochophore form after 20 hours (~ 200 micron). Shelled veliger after 48 hour (~225 micron long)

Transfer / removal method: Eggs and sperm collected in separate containers and mixed for fertilization.

Spawning tank size (liter): 250

Sides of tank covered? No

Lighting & photoperiod: ambient

Filtration: Open system. Tank is 1 x 1 x .25 meters

Additives and dosages: None

Water temperature (F): 48 – 53

Specific gravity: NSW


Fry development / changes: Massive mortality in culture at end of day 7 due to ciliate bloom(?). Remaining larvae (~ 100) settled and metamorphosed at 170 180 hours.

First food offered: non-feeding


1st week(%): 100

2nd week: 0.5

3rd week: 0.5

4th week: 0.25

Development description: Once larvae settle and metamorphose they live in the “scuz” on the bottom of the tank. Ciliate blooms are common in limpet cultures, possibly from initial water.

Rearing tank size (liter) 0.25 (beaker)

Lighting & photoperiod: ambient

Filtration: moved to open system 250 liter tank

Additives and dosages: none

Water temperature (F): same


Comments: Water flows through at an exchange rate of 500 liter / hour. Ciliates are believed to feed on unfertilized eggs, then attack embryo and larvae.

Word origins: Not, -a, -ae, -al, -o, =um, (Greek), the back. Acm, =a, (Greek), the highest point, a point. OR acmae, -o, (Greek), flourishing, mature. digit, -al, -I, (Latin), a finger or toe. The common name is finger limpet. The height of a limpets shell is sometimes associated with its position in the intertidal zone (Ricketts, et al, 1985), thus the genus word origins of “back with the highest point”

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. 1994

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