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This species has been observed on Reunion, Mayotte, Rodrigues, Mauritius and Madagascar Islands

Order : Cephalaspidea Superfamily : Philinoidea Family : Aglajidae Distribution : Tropical Indo-West Pacific Maximal size : 60 mm Abundance : From time to time on the reef flat zone Species characteristics : The body is creamish white with contrasting, strong black markings that are arranged in circles The posterior shield ends in two rounded lobes of equal length, but very short compared to Chelidonura The large bump at the top is caused by the buccal bulb inside the body which in these aglajids is a long narrow muscular tube, which lies folded up inside the head
	Showing species characteristics...	Photo Philibert Bidgrain Reunion, "Kelonia center", at Saint Leu, 13 December 2007, size : 40 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow and Hsini Lin
    Synonymous : (according Worms)
               - Philinopsis nigra Pease, 1860 (potentially, nomen oblitum)
               - Philinopsis pilsbryi (Eliot, 1900),

Bibliographic data :

Though distinctive, the colour patterns are variable.The extent of the black markings on the body vary beetween individuals. These can either be fine as to appear reticulate ( most often), or very thick as to give the appearance of an all black animal. One such dark animal had a pale orange-brown tinge overall     This is a large cephalaspidean which has a broad body.The head shield is approximately equal to the posterior shield in length and its posterior margin is not raised.There is a distinct bump on top of the head between the eyes. The left caudal lobe is slightly longer than the right lobe. The parapodia only cover the sides of the body.     The Aglajidae are all carnivorous hunters. The species of the genus Philinopsis can be divided into two groups.             -"Philinopsis taronga group" corresponding to Philinopsis species(ex : P speciosa ), have a large partially eversible buccal bulb. They use the buccal bulb to catch the bubble shells and other opisthobranchs.             -In "Philinopsis pilsbryi group" corresponding to Tubulophilinopsis species (ex T. gardineri, the buccal bulb is a long and narrow muscular tube. It is possible that they use the buccal bulb as a long eversible tube which can catch prey (worms?) in narrow burrows or crevices. Species with this foregut are usually quite easy to identify in the living animal as the folds of the tube form a rounded central crest on the head

Species of Tubulophilinopsis are usually found burrowing in sand or sandy mud.
    Certainly the white colour form of Tubulophilinopsis reticulata looks very similar to T. pilsbryi , but there is always bluish areas on T. reticulata, especially on the inside edge on the anterior part of the parapodia. Another distinguishing feature, is that in T. reticulata the reticulate pattern is also present on the sole of the foot , while it is usually absent in T. pilsbryi, although there can sometimes be a few black streaks.
    Specimens of the black color form of T pilsbryi have a superficial resemblance to T gardineri, but that always has blue markings on the parapodial margns

References :

Bill Rudman Seaslug site : Sea Slug Forum : Philinopsis pilsbryi
   Nudipixel Philinopsis pilsbryi

Publications :

Pease W.H. (1860). Descriptions of new species of Mollusca from the Sandwich Islands. Proceedings of the Zoological Society of London. 28: 18-36, 141-148
    Rudman,W.B., (1972) A comparative study of the genus Philinopsis Pease, 1860 (Aglajidae, Opisthobranchia). Pacific Science, 26 : 381-399
    Rudman,W.B., (1972) Structure and functioning of the gut in the Bullomorpha (Opisthobranchia). Journal of Natural History, 6 : 547-560
    Zamora-Silva A. & Malaquias M.A.E. (2017). Molecular phylogeny of the Aglajidae head-shield sea slugs (Heterobranchia: Cephalaspidea): new evolutionary lineages revealed and proposal of a new classification. Zoological Journal of the Linnean Society.

Other photos of Tubulophilinopsis pilsbryi :

Philibert Bidgrain. Reunion, "Kélonia center" a Marine Turtle Center in Saint Leu 8 December 2006, size : 45-50 mm

On the left : Species of Philinopsis are usually found burrowing in sand or sandy mud. On the sole of the foot, there can sometimes be a few black streaks.

Matthias Deuss Lagoon airport, Mayotte, 1m, 27 December 2008, size : 20 mm Crawling actively on the substrate...

   More photos from Indian Ocean

Mauritius, reticulate pattern for Tubulophilinopsis pilsbryi, by Patrick Millar

Reunion, creamish Tubulophilinopsis pilsbryi, at Saint gilles, by Eva Fontaine 

Rodrigues, Tubulophilinopsis pilsbryi, at Saint François, by Thierry Peres

Madagascar, Tubulophilinopsis pilsbryi, at Nosy Bé, by Alain-Benoît Rassat