Anatomical, morphological, and ecological notes on captive-bred Lissachatina Immaculata (Lamarck, 1822) (Gastropoda: Achatinidae), deliberately released into a central Mediterranean ecosystem

Abstract

The first occurrence of a ‘giant’ African land snail, Lissachatina immaculata (Lamarck, 1822), is hereby reported from a riparian ecosystem in the north-east of the island of Malta (central Mediterranean), through a collection of individuals in different stages of growth made in 2019. Monitoring of this site throughout the span of six years did not result in any subsequent finds; however, environmental management considerations are forwarded within this study to mitigate the establishment of yet another non-indigenous terrestrial pest species within the heavily bioinvaded Maltese Islands. The present species can be differentiated from confamilials and congeners through a combination of conchological and anatomical features, including a tiny protoconch, a patch of reddish colouration on the body whorl, and a loop emerging from the distal termination of the penial sheath.

[Noti anatomiċi, morfoloġiċi, u ekoloġiċi dwar Lissachatina immaculata (Lamarck, 1822) (Gastropoda: Achatinidae) imrobbija domestikament u mħarrba intenzjonalment f'ekosistema fil-Mediterran Ċentrali.] L-ewwel sejba ta’ bebbuxu tal-art ‘ġgant’ mill-Afrika, Lissachatina immaculata (Lamarck, 1822), qiegħda tiġi rrappurtata minn ekosistema riparja fil-grigal tal-gżira ta’ Malta (Mediterran ċentrali), permezz ta’ ġabra ta’ individwi fi stadji differenti ta’ żvilupp li saret fl-2019. Il-monitoraġġ ta’ dan is-sit matul sitt snin ma rriżulta f’ebda sejba sussegwenti; madankollu, kunsiderazzjonijiet ta’ ġestjoni ambjentali biex itaffu listabbiliment ta’ speċi oħra ta’ pesti terrestri mhux indiġeni fil-Gżejjer Maltin li huma bijoinvażi ħafna qiegħdin jiġu mressqa f’dan l-istudju. L-ispeċi preżenti tista’ tiġi differenzjata minn konfamiljari u konġeneriċi permezz ta’ sett ta’ karatteristiċi konkoloġiċi u anatomiċi, inklużi protokonka ċkejkna, roqgħa ta’ kulur ħamrani fuq l-aħħar dawra tal-qoxra, u ħolqa li tfiġġ mit-tarf distali tal-għant tal-pene.