Pyura discoveryi ( Herdman, 1910 )

Monniot, Françoise, Dettai, Agnès, Eleaume, Marc, Cruaud, Corinne & Ameziane, Nadia, 2011, Antarctic Ascidians (Tunicata) of the French-Australian survey CEAMARC in Terre Adélie, Zootaxa 2817, pp. 1-54 : 42-43

Pyura discoveryi ( Herdman, 1910)

( Figures 29 , 30 )

Halocynthia discoveryi, Herdman, 1910:9 . Pyura discovery Herdman 1912: 19 . Primo & Vazquez 2007: 1804 and synonymy.

Stations (events when several trawling operations per station): 3-6(99)-6(103)- 8-10-11 (424)-11(429)-16A-26A- 27(33)-27(45)27(46)-30(66)-31-34-35-36(68)-41-42-45-47-49A-57-62-71-79-86E.

The largest specimen of the collection is 5.5 x 4 cm. The body has always the same triangular shape with well apart protruding siphons ( Fig. 29 A) and a brown, hard, corrugated tunic. The basal part is often prolongated by threadlike extensions on fragmented substrate. The body wall is thin with regularly distributed muscles ( Fig. 29 B). A velum is present inside both siphons. The oral tentacles are poorly ramified in 3 orders of size. The dorsal tubercle is complex located inside a wide V of the peritubercular area. The dorsal lamina is made of long languets. The most ventral of the 7 branchial folds is lower on the left side ( Fig. 30 B). The branchial formula of a 35 mm specimen is:

E 1- 9 -4- 11 -5- 12 - 6- 16 -5- 20 -4- 16 -5- 12 -2-DL

DL- 3- 20 -3- 18 - 3- 20 -4- 20 - 3- 18 -3- 13 -3-8-1-E

Spiral stigmata can be seen at the top of the folds. The primary gut loop is widely open, the secondary curve is not obvious or absent ( Fig. 30 A).The anus is lobed. The long gonads have numerous lobes ( Fig. 30 A); the gonoducts are joined but become divergent at their extremity. No spinules could be detected on the siphon lining, even after a MEB examination.

One sequence for specimen S2 PYU 472a (BOLD: ASCAN044-10). No close hit in BOLD. This eurybathic species has a wide Antarctic distribution.

Figures

FIGURE 29. Pyura discoveryi: A, a specimen (copyright CEAMARC), scale bar = 1 cm; B, left side of a specimen without tunic.

FIGURE 30. Pyura discoveryi: A, body ventrally opened; B, branchial sac.