World Congress of Malacology Antwerp ... - Unitas Malacologica

New species of proneomenidae (Mollusca: Solenogastres) from Western Antarctica
García-Álvarez, Oscar 1 ; Zamarro, María 2 ; Gil-Mansilla, Esther 2 ; Urgorri, Victoriano 1,3
1. Departamento de Zooloxía e Antropoloxía Física, Facultade de Bioloxía,
Universidade de Santiago de Compostela, Spain,
Email: baoscar@usc.es
2. Unidade de Biodiversidade e Recursos Mariños. Instituto de Acuicultura,
Universidade de Santiago de Compostela, Spain,
3. Estación de Bioloxía Mariña da Graña. Rúa da Ribeira 1. 15590-Ferrol,
Universidade de Santiago de Compostela, Spain
The first anatomical data of two new species of proneomenidae from the Spanish campaign
BENTART’06 are presented for the study of the benthonic communities of western Antarctica
(Bellinghausen Sea and Antarctic Peninsula).
The family Proneomenidae (Solenogastres: Cavibelonia) is characterized by: thick cuticle with
several layers of hollow acicular sclerites; polistic-poliserial radula and epithelial ventrolateral
foregut glands (type C according to Salvini-Plawen, 1978) or exoepithelial glands with intraepithelial
glandular cells (according to Handl & Todt, 2005). The family is composed of two genera:
Pronemenia and Dorymenia, which differ in the absence/presence of copulative stylets.
Proneomenia sp. (a specimen from Bellingshausen Sea-603 m deep). It presents a foregut with
glandular cells in a dorsal groove; radula with 22-25 teeth per transverse row with a wide base and a
sharp and curved end; unpair opening of the spawning duct with a short and narrow duct; two kinds
of erythrocytes; paleal cavity without diverticula or respiratory folds; with abdominal spicules; a
dorsoterminal sense organ. It differs from P. gerlachei (Bellingahausen Sea-550 m deep) in its radula
structure.
Dorymenia sp. (two specimens from Livingston Islands-Southern Shetland Islands). It presents a
foregut with glandular cells and circular musculature; radula with 80-100 teeth per transverse row
with a wide base and a sharp and curved end; intestine with front caecum; two kinds of erythrocytes;
paleal cavity with diverticula, without respiratory folds and with two front bags (dorsal and ventral);
unpair ventral opening of the spawning duct into the the ventral bag of the paleal cavity; with
abdominal spicules; two dorsoterminal sense organs. It differs from the species of the genus from the
same geographic area and with a similar radular structure (D. hoffmani, D. usarpi, D. hesperidesi,
and D. menchuescribanae), in the arrangement of its paleal cavity.
Mating behaviour and spermathecal morphology in populations of the simultaneously
hermaphroditic land snail Helix aspersa
Garefalaki, M.E.; Koemtzopoulos, E.; Kalyva S.; Staikou, A.
Department of Zoology, School of Biology, Aristotle University, 54 124 Thessaloniki, Greece
Email: astaikou@bio.auth.gr
The edible snail Helix aspersa belongs to the simultaneous hermaphroditic species, which are
obligatory outcrossers. In this species multiple mating before egglaying is common leading to
increased sperm competition intensity. In this study we report results on mating behaviour (mating
propensity, copulation frequency, and copulation duration) and spermathecal morphology of snails
from several populations coming from the mainland of Greece and from the island of Crete which
differ in humidity regime of their habitat.
Mating propensity was assessed for each population by the percentage of snails mating at least once
during the reproductive period and for each snail by the duration of the latency period between its
activation and first mating. Our results indicated that mating propensity was stronger in snail
populations coming from drier habitats. Copulation frequency was also found higher in the same
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