Mémoires sur les animaux sans vertèbres / par Jules César Savigny.

Botrylloides crystallinus n. sp., a new Botryllinae Adams & Adams, 1858 (Ascidiacea) from Mediterranean Sea

“…In botryllids an aestivation with a total regression, was first described by Bancroft (1903) on colonies of Botrylloides gascoi Della Valle, 1877 (presently junior synonym of B. leachii) which at the end of June (in Naples) completely degenerated zooids and buds living only the test vascular system. The same phenomenon was described for B. leachii (Brunetti 1976) in the lagoon of Venice where the difference from winter and summer temperature is stronger (Pérès, 1949), B. israeliensis Brunetti, 2009 (Savigny, 1816), B. violaceus Oka, 1927. Special features: B. crystallinus n.…”

“…For a long time these animals were described almost exclusively on the basis of the shape of systems and their coloration, and a high number of species were defined. Thanks to the publication of the Faune de France (Harant & Vernières 1933) and The Tunicata (Berrill 1950) all European botryllid species were reduced to only two species: Botryllus schlosseri (Pallas, 1766) and Botrylloides leachii (Savigny, 1816). But this drastic decrease may be the reason why the Mediterranean Sea, although extremely rich and diverse for many biotas, appears so poor in terms of species diversity for botryllid genera.…”

Historical introduction, overview, and reproductive biology of the protochordates

“…Lamarck (1816) named the group Tunicata, and Cuvier (1815) added much to our knowledge of their anatomy but, along with many others, classified them with lamellibranch mollusks, an affinity that was endorsed as late as 1905 (Alder andHancock 1905-1907). Savigny (1816) clearly showed the relationship between solitary and colonial ascidians and also showed that they were not allied with the lamellibranch mollusks. Through most of the remainder of the 19th century there were numerous publications on the structure, larvae, and metamorphosis of ascidians, but no one had pointed out their obvious chordate nature.…”

Histological and haematological analysis of the ascidianBotrylloides leachii(Savigny, 1816) during whole-body regeneration

“…1), including a well-developed notochord, dorsal nerve cord, and a post-anal tail during their free-living tadpole larval stage. In particular, Botrylloides leachii (order Stolidobranchia, family Styelidae; Savigny, 1816) can undergo WBR in as little as 10 days (Rinkevich et al, 1995; Rinkevich et al, 2007, 2008, 2010; Zondag et al, 2016). Consequently, B .…”

“…leachii are sessile suspension-feeding ascidians that live in clonal colonies of adults, termed zooids, which organize in a series of ladder-like parallel rows, known as systems (Fig. 1 A-B; Brewin, 1946; Michaelsen, 1921; Savigny, 1816). The colony attaches to its substrate, typically underneath rocks in the shallow subtidal zone, through a gelatinous tunic.…”