Thomas Cassar

Il-fawna araknida tal-Gżejjer Maltin gℏadha ma ġietx investigata adegwatament. Fix-xogℏol preżenti, minn total ta’ 117 speċi li nġabru, 37 speċi huma ġodda gℏal Malta – 36 brimb (Araneae) kif ukoll speċi waℏda ta’ busaqajn (Opiliones). Dawn l-ispeċi jinkludu tliet familji ta’ brimb u familja waℏda ta’ busaqajn ġodda gℏall-arċipelagu Malti: Anyphaenidae Bertkau, 1878; Mimetidae Simon, 1881; Oxyopidae Thorell, 1869 u Sclerosomatidae Simon, 1879; kif ukoll żewġ speċi li huma ġodda gℏall-Ewropa: Acartauchenius insigniceps (Simon, 1894) u Zelotes poecilochroaeformis Denis, 1937. Noti ekoloġiċi, distribuzzjonali, bijoġeografiċi u tassonomiċi huma pprovduti gℏall-ispeċi rrekordjati.

Megachile parietina (Geoffroy, 1785), the black mud bee, is recorded from the Maltese Islands for the first time on the basis of two adult nesting females and four nests from Pembroke (north-east of Malta). This addition to the Maltese entomofauna brings the number of bees known from the archipelago to 106. The possibility that this species could be a suitable pollinator of the endemic orchid Ophrys melitensis (Salk.) Devillers-Terschuren & Devillers, 1994 is discussed, and further investigation is encouraged.

The intranidal myrmecophilous arthropod fauna of the Maltese Islands is reviewed. Thirty species from nine orders are found to be obligate myrmecophiles, of which four species are recorded from the Maltese archipelago for the first time: Phrurolithus sp. (Araneae: Phrurolithidae), Pogonolaelaps canestrinii (Berlese, 1904), Gymnolaelaps messor Joharchi, Halliday, Saboori & Kamali, 2011 and G. myrmecophilus (Berlese, 1892) (Mesostigmata: Laelapidae). Phrurolithus also represents the first record of the family Phrurolithidae in Malta. Notes on the biology and local distribution of each species are provided, including ant-myrmecophile associations, of which two appear to be previously unknown: the occurrence of Smynthurodes betae Westwood, 1849 (Hemiptera: Aphididae) in the nest of Plagiolepis pygmaea (Latreille, 1798) and Phrurolithus in the nest of Pheidole pallidula (Nylander, 1849). Fourteen additional species are found to be either only occasionally myrmecophilic, accidental ant-guests or potentially myrmecophilous, the latter remaining ambiguous due to a lack of knowledge of their biology. Of these, the family Caeculidae (Arachnida: Trombidiformes) represents a new record for the Maltese Islands, on the basis of Microcaeculus sp. occurring in a nest of Camponotus barbaricus Emery, 1905. Preliminary results indicate that Messor nests may be repositories of considerable myrmecophile diversity, with the most unique symbionts.

Contrary to what its name suggests, Nemesia arboricola is not strictly arboreal in habit. Here we compare female specimens of N. arboricola collected from arboreal and terrestrial nests. We furthermore describe the male of N. arboricola for the first time as well as two recently discovered species of Nemesia (N. maltensis sp. nov. and N. cominensis sp. nov.). Nemesia maltensis is described from both sexes, N. cominensis is described from the female and a juvenile male specimen. For N. cominensis we discuss the sexual dimorphism of juvenile male and female spiders. Field observations and laboratory observations show remarkable features of the Maltese Nemesia fauna that are unknown from Nemesia species found elsewhere. Particularly, the arboreal dwellings of N. arboricola and the absence of a trapdoor to close off the burrow entrance in N. maltensis appear to be exceptional. The composition of the Maltese Nemesia fauna, as located in the central Mediterranean, is finally discussed in relation to the different Nemesia species-complexes occurring in the eastern and western Mediterranean basin.

The Dysderidae fauna of the Maltese Islands is reviewed. Dysdera kollari Doblika, 1853, D. lagrecai Alicata, 1964 and Harpactea sicula Alicata, 1966 are recorded for the first time from the Maltese archipelago, and the latter two species are recorded for the first time outside Italian territories. Harpactea corticalis (Simon, 1882) is removed from the Maltese dysderid fauna list. Distributional notes for all four species present in the Maltese Islands are provided, with the first records of Dysderidae from Comino.

The gasteruptiid fauna of the Maltese archipelago is reviewed for the first time. Four species of Gasteruption are found to inhabit the Maltese Islands, and Gasteruption tanyakronum n. sp. van Achterberg is described on the basis of material collected from Malta and Sardinia (Italy).