OAR@UM Community:
/library/oar/handle/123456789/125980
2026-06-14T05:02:06ZIntegrative morphology and biogeography reveal cryptic diversity in Muticaria from central and southeastern Sicily : a multivariate approach to species delimitation with the description of 60 new taxa (Mollusca : Gastropoda : Clausiliidae)
/library/oar/handle/123456789/144737
Title: Integrative morphology and biogeography reveal cryptic diversity in Muticaria from central and southeastern Sicily : a multivariate approach to species delimitation with the description of 60 new taxa (Mollusca : Gastropoda : Clausiliidae)
Authors: De Mattia, Willy; Reitano, Agatino
Abstract: The genus Muticaria Lindholm, 1925 represents one of the most taxonomically complex radiations of Mediterranean clausiliids, characterized by extreme micro-allopatry, strong shell homoplasy, and limited dispersal ability. Traditional shell-based taxonomy has proven inadequate for resolving species boundaries within this genus, often leading to artificial lumping or unstable classifications. In this study, we present a comprehensive morphological revision of Muticaria from central and southeastern Sicily, integrating detailed genital anatomy with quantitative morphometrics and explicit geographic constraints. A total of 228 dissected specimens from 75 populations were analysed using a size-free multivariate framework based primarily on genital characters. Morphological distances (Mahalanobis Distance) were combined with geographic proximity thresholds and no-chain constraints within a STRICT species-delimitation algorithm designed to reflect biologically realistic micro-allopatric diversification. Hierarchical clustering, principal component analyses, and discriminant analyses consistently recovered a structured pattern of differentiation, revealing 33 well-defined species-level entities. Of these, 28 are described here as new to science (60 taxa including species and subspecies), while five correspond to previously recognized taxa used as taxonomic anchors. Shell morphology, although extensively documented, proved highly homoplastic and insufficient for species delimitation when analysed independently, but remains informative for documenting intraspecific and subspecific variation once species boundaries are defined anatomically and geographically. Unconstrained clustering based on morphology alone produces biologically implausible groupings, highlighting the necessity of integrating spatial structure into taxonomic decision-making. Our results demonstrate that genital morphology, evaluated within an explicit morpho-geographic framework, provides a robust and reproducible basis for species delimitation in non-adaptive radiations of low-dispersal land snails. The approach adopted here offers a generalizable model for resolving taxonomic complexity in other morphologically conservative and geographically fragmented systems.; [Integrazzjoni ta’ morfoloġija u bijoġeografija tiżvela diversità kriptika f'Muticaria
miċ-ċentru u x-xlokk ta' Sqallija: approċċ multivarjat għad-delimitazzjoni tal-ispeċi
bid-deskrizzjoni ta’ 60 tasson ġdid (Mollusca: Gastropoda: Clausiliidae).] Il-ġeneru
Muticaria Lindholm, 1925 jirrappreżenta waħda mill-aktar radjazzjonijiet tassonomikament
kumplessi tal-klawsiljidi tal-Mediterran, ikkaratterizzata minn mikro-allopatrija estrema, qxur
b’omoplażija qawwija, u kapaċità għat-tixrid limitata. It-tassonomija tradizzjonali bbażata fuq ilqoxra mhijiex biżżejjed biex jiġu solvuti l-konfini tal-ispeċi f'dan il-ġeneru, u ħafna drabi twassal għal
raggruppamenti artifiċjali jew klassifikazzjonijiet instabbli. F'dan l-istudju qegħdin nippreżentaw
reviżjoni morfoloġika komprensiva tal-Muticaria minn Sqallija ċentrali u tax-xlokk, bl-integrazzjoni
ta’ anatomija ġenitali dettaljata flimkien ma' morfometrija kwantitattiva u limiti ġeografiċi espliċiti.
Total ta’ 228 kampjun dissezzjonat, minn 75 popolazzjoni, ġie analizzat permezz ta’ qafas multivarjat
(mingħajr id-daqs) ibbażat primarjament fuq il-karattri ġenitali. Id-distanzi morfoloġiċi (distanza ta’
Mahalanobis) ġew ikkombinati ma' limiti ta’ prossimità ġeografika u restrizzjonijiet mingħajr katina
fi ħdan algoritmu STRICT ta' delimitazzjoni tal-ispeċi, iddisinjat biex jirrifletti diversifikazzjoni
mikro-allopatrika bijoloġikament realistika. Raggruppament ġerarkiku, analiżi tal-komponenti
prinċipali, u analiżi diskriminanti rkupraw b’mod konsistenti mudell strutturat ta’ differenzjazzjoni,
u żvelaw 33 entità fil-livell ta’ speċi b’definizzjoni tajba. Minn dawn, 28 huma deskritti hawn bħala
ġodda għax-xjenza (60 tasson, inklużi speċi u sottospeċi), filwaqt li ħamsa jikkorrispondu għal
tassoni diġa magħrufin, li qegħdin jiġu użati bħala ‘ankri’ tassonomiċi. Il-morfoloġija tal-qoxra,
għalkemm dokumentata b’mod estensiv, irriżultat omoplastika ħafna, u allura insuffiċjenti għad-delimitazzjoni tal-ispeċi meta analizzata b’mod indipendenti, għalkemm tibqa’ siewja fiddokumentazzjoni ta’ varjazzjoni intraspeċifika u sottospeċifika ladarba l-konfini tal-ispeċi ġew
definiti anatomikament u ġeografikament. L-iggruppament mhux ristrett ibbażat fuq il-morfoloġija
biss jipproduċi gruppi bijoloġikament implawżibbli, u jenfasizza l-ħtieġa li tiġi integrata l-istruttura
spazjali fit-teħid ta’ deċiżjonijiet tassonomiċi.
Ir-riżultati tagħna juru li l-morfoloġija ġenitali, evalwata fi ħdan qafas morfo-ġeografiku espliċitu,
tipprovdi bażi robusta u riproduċibbli għad-delimitazzjoni tal-ispeċi f’radjazzjonijiet mhux adattivi
ta’ bebbux tal-art b’kapaċità għat-tixrid limitata. L-approċċ adottat hawn joffri mudell
ġeneralizzabbli għar-riżoluzzjoni tal-kumplessità tassonomika f’sistemi oħra li huma
morfoloġikament konservattivi u ġeografikament frammentati.2026-01-01T00:00:00ZBulletin of the National Museum of Natural History, Malta : volume 2, issue 2
/library/oar/handle/123456789/142517
Title: Bulletin of the National Museum of Natural History, Malta : volume 2, issue 2
Authors: Cilia, David P.
Abstract: Table of Contents:; - A vegetation survey of Wied Dalam, Birżebbuġa, Malta, for October 2024 to May 2025 - Briffa, Melanie;; - Flora Melitensis : a natural history gem from the village of Żabbar, Malta - Sciberras Arnold & Sciberras Jeffrey;; - The genera Murexsul Iredale, 1915 and Muricopsis Bucquoy & Dautzenberg, 1882 in Maltese waters, with the description of a new species (Gastropoda : Muricidae) - Cachia, Charles;; - A new species of Vitrinella Adams, 1850 (Gastropoda : Littorinimorpha : Vitrinellidae) from the eastern Mediterranean - Ovalis Panayotis & Mifsud Constantine;; - Anatomical, morphological, and ecological notes on captive-bred Lissachatina Immaculata (Lamarck, 1822) (Gastropoda : Achatinidae), deliberately released into a central Mediterranean ecosystem - Cilia, David P., Sciberras, Arnold & Deidun Alan;; - Historical gardens as green refugia in the urban fabric : a case study from Villa Guardamangia in Malta - Cilia, David P.;; - Preserving the skeletons in our historic closet - Licari, James2025-01-01T00:00:00ZA vegetation survey of Wied Dalam, Birżebbuġa, Malta, for October 2024 to May 2025
/library/oar/handle/123456789/142516
Title: A vegetation survey of Wied Dalam, Birżebbuġa, Malta, for October 2024 to May 2025
Authors: Briffa, Melanie
Abstract: The valley of Wied Dalam (Birżebbuġa, Malta) was surveyed four times (from October 2024 till May
2025), to investigate the plant species composition, species density, and the most dominant species
in each habitat type, following ecological restoration and management initiatives carried out in the
locality in recent years. This was carried out using a belt transect (3 m) with a quadrat (1 × 1 m), and
results were analysed using the Braun-Blanquet Scale. The western side of the valley had a higher
species richness of maquis undergrowth species, especially at high densities of Arundo donax L. and
Ceratonia siliqua L., while the eastern side of the valley had more ruderal and arid-tolerant species
typical of open ground. Species composition and abundance differed due to seasonal conditions and
recent anthropogenic disturbance. The rare Allium triquetrum L., and the scarce Glebionis segetum
(L.) Fourr., Poa annua L., and Scandix pecten-veneris L. were noted. Numerous plant species that
were recorded in past studies were not observed during the surveys, while several invasive plant
species still persist throughout the valley. These findings highlight the current situation regarding
vegetation composition as present at Wied Dalam throughout the sampling year 2024–2025, as well
the importance of long-term vegetation monitoring following ecological restoration actions, such as
those undertaken in this location.2025-01-01T00:00:00ZFlora Melitensis : a natural history gem from the village of Żabbar, Malta
/library/oar/handle/123456789/142515
Title: Flora Melitensis : a natural history gem from the village of Żabbar, Malta
Authors: Sciberras, Arnold; Sciberras, Jeffrey
Abstract: In 2013, a neglected herbarium entitled Flora Melitensis was rediscovered at the St. Margaret College
(Primary B) in Żabbar, Malta. Housed in a custom-built cabinet and dating to 1951–1952, the
collection originally comprised around 150 plant specimens prepared by teachers and students as
part of an innovative natural history curriculum. Upon discovery, the herbarium was in a state of
severe deterioration caused by pest infestations, decayed protective materials, and specimen loss. A
ten-month restoration project was undertaken to preserve its scientific and historical value. This
process included cleaning, freeze-drying, fumigation, specimen and label conservation, and the
replacement of missing plants with newly collected or cultivated material. Of the original specimens,
72 were extant and could be saved, while 32 were recollected from the wild, and eight were
recollected from cultivated specimens purposely grown for the collection. Historical investigation
confirmed the herbarium’s origins within one of Malta’s earliest initiatives to integrate
environmental education in state schools. The restored Flora Melitensis, now forming part of the
collection at the National Museum of Natural History in Malta, now serves as both a botanical archive
and a cultural artefact, preserving a unique intersection of Maltese floristics, pedagogy, and heritage.2025-01-01T00:00:00Z