Phallusia, Savigny, 1816

Monniot, Françoise, 2018, Ascidians collected during the Madibenthos expedition in Martinique: 1 - Phlebobranchia, Zootaxa 4387 (3), pp. 451-472 : 465-466

Phallusia sp.

Figs 13 , 14 , 15

Station: AB 159 (MNHN P5 PHA 127)

A specimen 5cm long has an ovoid shape with a very smooth stiff colourless tunic. It was attached by its whole ventral side. The oral siphon is apical. The atrial siphon is slightly protruding at 1/2 of the body length its aperture directed anteriorly. Internal organs are not pigmented ( Fig 13 ). All anatomical characters are the same as those described for P. nigra collected from the nearby stations. The prepharyngeal area is narrow with papillae ( Fig. 15A ). The dorsal tubercle opens in a small C. The neural ganglion and the neural gland are close to the base of the atrial siphon ( Fig 15B ). The duct of the neural gland has numerous apertures along its whole length ( Fig.14 A ; 15B,C). The branchial sac ( Fig. 14B ) has round papillae some of them with a basal extension. A line of long pointed papillae extends on the right side of the oesophageal aperture ( Fig. 14B ). The gut in a double loop has no inflated rectal pouch (Fig; 13; 14A). The musculature ( Fig.14A ) has exactly the same design as that described for P. nigra .

This ascidian may be an albino specimen as even in formalin P. nigra keeps its deep black colour even stored in formalin during many years.

Figures

FIGURE 13. Phallusia sp. Left (A) and right (B) sides of the body without tunic. Scale bar = 1cm

FIGURE 14. Phallusia sp. A, dissection stained with hemalum; B, branchial tissue around the oesophagus; C, detail of the branchial tissue.

FIGURE 15. Phallusia sp. A, prepharyngeal area; B, accessory openings of the neural gland; C, detail of neural gland openings.(Tissues stained with hemalum)