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

Order : Cephalaspidea Superfamily : Philinoidea Family : Aglajidae Distribution : Tropical Indo-West Pacific Maximal size : 50 mm Abundance : Seldom on the fore reef zone and on the reef flat zone Species characteristics : The body colour ranges from white to dull yellow and there is a reticulate pattern of brown to black all over the body, including the sole of the foot. There are blue markings on the inside edge of the anterior part of the parapodia and along the outer edge of the parapodia. 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 Stéphane Ciccione Reunion, "Kelonia center", at Saint Leu, 20 February 2008, size : 25-30 mm

See more about : Sightening and mating periods
   See more about : Tubulophilinopsis reticulata variability in Southwest Indian ocean
   See more about : Tubulophilinopsis reticulata burrowing on the sand

Remarks

Identification confirmed by Bill Rudman and Hsini Lin
    The specimens found in Réunion and Mayotte Islands corresponded to the darker brown colour form with a much smaller reticulation which is usually found from East Africa to the Western Pacific.
    Synonymous (according worms and Gosliner, 1980) :
               - Aglaja phaeoreticulata Yonow, 1990               - Doridium reticulatum Eliot, 1903               - Philinopsis reticulata (Eliot, 1903)
               - Philinopsis reticulatum (Eliot, 1903)                - Aglaja reticulata ( Eliot, 1903)

Bibliographic data :

The colour pattern of this species animal is variable : white colour form with an open black reticulation, is found from the Red Sea to New Caledonia, and a darker brown colour form with a much smaller reticulation is found from East Africa to the Western Pacific.     The Aglajidae are all carnivorous hunters. The species of the genus Philinopsis can be divided into two groups.             -"Philinopsis taronga group" (ex : P cyanea), have a large partially eversible buccal bulb. They use the buccal bulb to catch the bubble shells and other opisthobranchs.             -In "Philinopsis pilsbryi group" (ex P 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     Eliot describes this as "pharynx of moderate size, 1.5 mm wide" which means little until it is compared with his description of the foregut of a similarly sized specimen of Philinopsis cyanea - "pharynx is colossal ... breadth 15mm"     Certainly the white colour form of Philinopsis reticulata looks very similar to P. pilsbryi , but there is always bluish areas on P. reticulata, especially on the inside edge on the anterior part of the parapodia. Another distinguishing feature, is that in P. reticulata the reticulate pattern is also present on the sole of the foot , while it is usually absent in P. pilsbryi, although there can sometimes be a few black streaks.   illustration to the right is from Eliot, 1903, Pl. 13, fig. 1.

References :

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

Publications :

Eliot, C.N.E. (1903) Notes on some new or little known members of the family Doridiidae. Proceedings of the Malacological Society, London, 5(5): 331-337
    Gosliner, T. M. (1980) Systematics and phylogeny of the Aglajidae (Opisthobranchia: Mollusca). Zoological Journal of the Linnean Society, 68: 325-360.
    Yonow, N. (1990) Red Sea Opidthobranchia 3: The orders Sacoglossa, Cephalaspidea, and Nudibranchia: Doridacea (Mollusca, Opisthobranchia). Fauna of Saudi Arabia, 11: 286-299.
    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 Philinopsis reticulata :

Stéphane Ciccione Reunion, "Kelonia center", at Saint Leu, 20 February 2008, size : 25-30 mm The underside of this animal, with the caracteristic reticulate pattern on the sole of the foot

Detail of the anterior with : The eye (black spot) The bluish areas, especially on the inside edge on the anterior part of the parapodia The rounded central crest (large bump )on the head The reticulate pattern of brown to black all over the body

Maurice Jay Reunion, Saint Paul

Sophie Darnis Reunion, "La vallée aux mérous", at Saint Gilles, 38m, 17 May 2008, size : 30 mm The blue markings on the inside edge of the anterior part of the parapodia and along the outer edge of the parapodia are well develloped in this specimen

Eva Fontaine mbouéanatsa at Mayotte, crawling during the day on the substrate, reef flat zone, less 1 m, 5 August 2008, size : 15 mm. A small specimen without blue marking along the outer edge of the parapodia. The underside , with the caracteristic reticulate pattern on the sole of the foot

Seb Vasquez Reunion, Etang salé, 10 December 2014   with its spawn...

   More photos from Indian Ocean

See more about : Philinopsis reticulata variability in Southwest Indian ocean

See more about : Philinopsis reticulata burrowing on the sand

Mayotte, Philinopsis reticulata with blue marks, at mbouéanatsa, by Philibert Bidgrain

Reunion, Philinopsis reticulata, at Etang salé, by Eva Fontaine 

Réunion, Philinopsis reticulata in Kelonia center, at Saint Leu, by Lucie Maillot  

Reunion, mating behavior in Philinopsis reticulata, at Etang salé, by Hugues Flodrops  

Mauritius, Philinopsis reticulata, by Pierre Périès

Madagascar, Philinopsis reticulata, at Nosy Bé, by Alain-Benoît Rassat