EMBLANDIDAE PONDER, 1985

Criscione, Francesco, Ponder, Winston Frank, Köhler, Frank, Takano, Tsuyoshi & Kano, Yasunori, 2017, A molecular phylogeny of Rissoidae (Caenogastropoda: Rissooidea) allows testing the diagnostic utility of morphological traits, Zoological Journal of the Linnean Society 179 (1), pp. 23-40 : 34

FAMILY EMBLANDIDAE PONDER, 1985

This monotypic group was erected as a family by Ponder (1985b). In our analysis it is the basal member of a clade that also contains Merelina and Lironoba ( Lironobidae ) and together they are the sister taxon of the Rissoidae . It is distinguished from all other rissooideans in having a double-layered operculum (a character otherwise known from the Anabathridae ; Supporting Information, Fig. S1A), a radula that has only central and lateral teeth (i.e. three rows rather than seven as in all other rissooideans and truncatelloideans; Fig. 3H ), and the jaws are lacking, a character unknown in other rissooideans. Additional autapomorphic characters include: a very narrow propodium; a very thick hypobranchial gland; a hypobranchial gland sheath for the penis; short anterior salivary glands; and tiny style sac (much shorter than in all other related taxa). The posterior chamber of the stomach is rather longer than in most rissooideans, although much shorter than in Rissoinidae , so we have scored it as ‘short’ in Supporting Information, Fig. S1C. The female genital system was not studied in full by Pon- der (1985b) and it is unknown whether the upper oviduct gland is present or absent.

Figures

Figure 3. Maximum-likelihood-based ancestral character state reconstruction for anatomical characters mapped on the Bayesian consensus tree of Fig. 1. A, shell anterior canal. B, duplicated peristome. C, shell inner organic layer. D, opercular peg. E, pallial tentacles. F, metapodial tentacles. G, posterior mucous gland. H, basal cusps on rachidian tooth. Taxa for which anatomical information was not available have been excluded from the tree. Branches with BPP support values lower than 90% are shown as collapsed. A likelihood of state at each node lower than 1% is omitted.