Carlo Cunha

The family Elachisinidae Ponder, 1985 includes minute marine gastropods that live predominantly in the sublittoral zone (Ponder & Keyzer 1998; Rolán & Rubio 2001; Rolán & Gofas 2003). Most elachisinids have been included in the genus Elachisina Dall, 1918 based on their shell morphology (Warén 1996; Rolán & Rubio 2001; Rolán & Gofas 2003), consequently, very little is known about the habitat and ecological niche of the species (Ponder & Keyzer 1998; Rolán & Gofas 2003). Elachisina floridana (Rehder, 1943) is the only Atlantic congener collected alive, and is known to live beneath rocks and in rocky crevices in the intertidal zone to about 1 m depth in the Bahamas and Caribbean Sea (Ponder 1985; Ponder & Keyzer 1998; Rolán & Gofas 2003; Redfern 2013). Eastern Atlantic E. canarica (Nordsieck & García-Talavera, 1979) was also collected alive from the Canary Islands, but with no information on the habitat (Rolán & Gofas 2003). The islands of the northeastern Atlantic and West Africa are the regions with the greatest Elachisina richness known, totaling nine species (Rolán & Rubio 2001; Rolán & Gofas 2003). Only E. floridana has been recognized so far to be widely distributed throughout the Western Atlantic (Rolán & Gofas 2003; Rios 2009; Redfern 2013).

The genus Liocarenus (Acteonidae) was originally described from Eocene fossil material and has subsequently come to include three subgenera (Liocarenus s. s., Bulimactaeon and Nucleopsis) and nine species, including a Recent one (L. globulinus). Together, these have been accorded status as a subfamily, Liocareninae. We here present a taxonomic revision of all the species and subgenera historically ascribed to Liocarenus. We show that the genus name Liocarenus is an objective synonym of Hemiauricula. All three taxa (Bulimactaeon, Hemiauricula and Nucleopsis) are accepted at genus level and a new genus, Rapturella, is erected for the Recent species. Rapturella is diagnosed by a thick shell with rounded whorls, slightly stepped spire, two closely spaced subsutural spiral grooves, a weak columellar fold and a tooth-like palatal thickening.

Land snails (stylommatophoran pulmonates, shells only) were collected on Trindade Island, 1140 km off Vitória, Brazil, by the Marion Dufresnei Expedition (MD-55) and more recently by our team. Trindade's endemic snails are Bulimulus brunoi and Naesiotus arnaldoi (Orthalicidae), and Oxyloma beckeri and Succinea lopesi (Succineidae). As some non-native species have also been found, a taxonomic revision of the native fauna was needed. Here, the revision is focused on orthalicids, presenting updated descriptions and diagnosis. Moreover, the supposed native orthalicid Bulimulus trindadensis is deemed here to be a Subulinidae, and the new genus Vegrandinia is erected to accommodate it. Trindade's insular environment is delicate and very susceptible to invasive species. No living specimens of these taxa, native or non-native, have been collected since before the MD-55 Expedition. However, it is still premature to assume that the introduced species have failed to establish themselves or that the native species are now extinct. http://www.zoobank.org/urn:lsid:zoobank.org:pub:6B1D6F63-EFB0-400A-8C0C-B508EAEB0A4B

The present redescription of Diplodonta portesiana (d’Orbigny, 1846) is the first part of the revision of
this genus in the East Atlantic. This species, despite being common in the Atlantic coast, remains poorly
known. A detailed shell and anatomical study was conducted based not only on specimens from the
type locality’s vicinities but also on samples from other regions. Diagnostic characters for D. portesiana
includes: rounded shell with a small ligament; triangular, short and deep nymph; external micro ornamentation
composed of small concavities in a concentric pattern; small adductor muscles; reduced pedal gape;
pair of long hemipalps with a large area covered by folds; stomach with four ducts leading to digestive
diverticula; and long intestine length. Our study suggests at least two new diagnostic characters to the
genus: the two pair of muscles that controls the incurrent and excurrent openings and a residual ring-like
tissue surrounding the anterior half of the posterior foot retractor muscle.

Trindade is an oceanic island 1140 km off Vitória, Brazil. The Marion Dufresne Expedition (1987) recovered there many land snail shells, all stylommatophoran pulmonates. Here, four microgastropod species found in this material are recorded for the first time on Trindade Island: Lilloiconcha gordurasensis (Charopidae), Pupisoma macneilli (Valloniidae), Gastrocopta barbadensis (Gastrocoptidae) and Vertigo sp. (Vertiginidae). The last one could be a non-native, introduced species. Unfortunately, none of these species can be currently found alive on the island, which can be indicative of extinction.

For four decades it has been suspected that the endemic land snails of Trindade Island, Brazil, were extinct. Here we report finding live Succinea lopesi Lanzieri, 1966 and a species of Happia Bourguignat, 1889 on top of the island's highest peaks. Happia is a new record for the island and possibly also a new endemic species. As Trindade's environment has suffered much degradation due to introduced feral goats, such remote places might have acted as refuges for the snails. With the ongoing recovery of the native flora after the eradication of the goats, the snails' populations might re-establish themselves.