Ercolania kencolesi     Grzymbowski, Stemmer & Wägele, 2007

This species has been observed on Reunion Island


Order : Sacoglossa
Superfamily : Limapontioidea
Family : Limapontiidae
Distribution : Known from Great Barrier Reef, Nth Queensland, Guam and now Reunion
Maximal size : 9 mm
Abundance :


Species characteristics :

Overall body and head are green with black eyes hardly visible

Long green rhinophores with white tips

Cerata darker green, darkest at apical end with subapical white blotches forming an incomplete ring.

Found in or around in the syncytial algal tubes Boergesenia forbesii

ercolania kencolesi
Showing species characteristics...

Photo Philibert Bidgrain
Reunion, La Saline lagoon, Saint Gilles, less 1 m, 19 February 2010, size: 9 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Kathe Jensen
    Thanks to Bruno Navez who informed me of the presence of this species in Saint Pierre Lagoon
    Boergesenia forbesii is a species listed in Reunion Island ( Silva, C., P. Basson & R. Moe, 1996)
    Synonymous : (according Worms)
               - No other name

Bibliographic data :

This species is dedicated to Ken Coles, a great sponsor of the Lizard Island Research Station (LIRS). With his donations, he supports many scientists doing research in the well-equipped laboratories.
    Overall colour of body green; under higher magnification, green disintegrating to green dots representing terminal parts of numerous tiny digestive glandular branches.
    Rhinophores green with white tips are long, solid and digitiform; in median part with a white blotch nearly circling rhinophore.
    Cerata club-shaped to sausage-shaped, in one to two rows, with smaller ones on outer side. Cerata not standing very close. Central notum free of any cerata
    Cerata darker green, darkest at apical end with subapical white blotches forming an incomplete ring. More patches especially in dorsal areas of cerata.
    Body elongate, foot tapering posteriorly and anteriorly without a notch and any propodial tentacles, but slightly extended to lateral sides
    Anterior margin of foot light green to whitish
    Measurement of photosynthetic activity of incorporated chloroplasts during several days clearly shows that chloroplasts are digested. Not as other species where the chloroplasts of the food algae are incorporated into the digestive gland and retain their ability to perform photosynthesis for a period of time ranging from hours to months...
    After starving for two to three days, animals showing a more brownish colour and eyes becoming more visible
    E. kencolesi has a similar biology as E. endophytophaga. Both are living within syncytial algal tubes of members of the Siphonocladales, E. kencolesi in Boergesenia forbesii and E. endophytophaga in Struvea plumosa.
    Feeding observations in laboratory : (Grzymbowski, Y., Stemmer, K. & Wagele, H. 2007)
              - Ercolania kencolesi crawled on top of the first third of one algal tube, sat there for about three to four minutes with the ventral part of the head firmly attached to the alga. In these minutes, the slug pierced the algal cell wall and then started to push the head into the alga.
              - After seven minutes the slug had penetrated completely into the tube
              - It crawled up and down while slurping the cell sap. The mouth opened regularly for this action.
              - After 45 minutes, 2/3 of the whole sac was sucked out by the slug
              - After 80 minutes it stopped searching and was crawling rather lazily. There are always small patches of chloroplasts which were still recognizable
              - After 18 hours, even those patches were gone
              - Two days after the intrusion, an egg clutch attached to the algal cell wall was observed
              - Then, the slugs left the algal sac and intruded into another algal tube.
    Egg lying observations in laboratory : (Grzymbowski, Y., Stemmer, K. & Wagele, H. 2007)
              - The egg mass is a cylindrical tube (up to 1 mm in diameter) coiled anticlockwise into planar spirals of two and a half whorls
              - It is attached to the inner wall of Boergesenia forbesii.
              - Usually one animal laid two egg masses inside the same algal sac.
              - Egg masses measure 45 mm in diameter and contain around 500 egg capsules, each with one white egg (size about 100 m) inside. Capsules are rather spherical and measure around 215 m

References :

Bill Rudman Seaslug site : Sea Slug Forum : Ercolania kencolesi

Publications :

Grzymbowski, Y., Stemmer, K. & Wagele, H. 2007 On a new Ercolania Trinchese, 1872 (Opisthobranchia, Sacoglossa, Limapontiidae) living within Boergesenia Feldmann, 1950 (Cladophorales), with notes on anatomy, histology and biology. Zootaxa , 1577: 3-16
    Silva, C., P. Basson & R. Moe (1996). Catalogue of the Benthic Marine Algae of the Indian Ocean. Volume 79 of University of California Publications in Botany (ISBN 0-520-09810-2

Other photos of Ercolania kencolesi :


 

 

Jean-Pascal Quod

Réunion, Trois bassins, January 2017, size : 3 mm

 


Philibert Bidgrain

Reunion, La Saline lagoon, Saint Gilles, less 1 m, 17 February 2010, size: 6 mm

After 80 minutes it stopped searching and was crawling rather lazily. There are always small patches of chloroplasts (a) which were still recognizable

Found in or around in the syncytial algal tubes Boergesenia forbesii


 

 

PHilibert Bidgrain

Reunion, La Saline lagoon, Saint Gilles, less 1 m, 17 February 2010, size: 6 mm

View from the dorsum :

Overall colour of body green; under higher magnification, green disintegrating to green dots (a) representing terminal parts of numerous tiny digestive glandular branches.

View from the sole of the foot :

Overall colour of body green; under higher magnification, green disintegrating to green dots (a) representing terminal parts of numerous tiny digestive glandular branches.

Anterior margin of foot (b) light green to whitish

Cerata darker green, darkest at apical end (c) with subapical white blotches (d) forming an incomplete ring.

Long green rhinophores with white tips (e)


Philibert Bidgrain

The slugs left the algal sac

Reunion, La Saline lagoon, Saint Gilles, less 1 m, 19 February 2010, size: 9 mm

Central notum (a) free of any cerata

Cerata darker green, darkest at apical end (b) with subapical white blotches forming an incomplete ring (c).

More patches especially in dorsal areas of cerata.

Black eyes (d) hardly visible


Nathalie Rodrigues

Reunion, Etang salé on the rocky coast, less 1 m, December 2014

 

A search of food... the syncytial algal tubes Boergesenia forbesii


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