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Special thanks to: Guido Bonett for all photos accompanying the article on Brachytrupes megacephalus. National Museum of Archaelogy for providing the photo of Ramla bay in Gozo in the article on Viteus vitifoliae and Oliver Pace for photo of galls of Grape Phylloxera. Dan Magsbo, John Hallmen and Nicholas J. Vereecken for the insect photos in the article on Apalus bimaculatus and the National Museum of Natural History for the portrait of Alfredo Caruana Gatto. 123

Hyles sammuti This moth belongs to a group of insects commonly known as Hawk-moths. They are among the fastest flying insects reaching speeds of up to 50 km/hr. Most species are represented by relatively large moths and the caterpillar has a characteristic curved horn at its hind end. Caterpillars are fast growing and when they are fully grown they need to bury themselves under soil for pupation where they may stay for up to one year prior to adult emergence. Until 1998, Hyles sammuti was known as Hyles euphorbiae, a common species throughout Europe, but from recent studies it was shown that the Maltese population was different from that of mainland Europe. The species was in fact described as a new species to science and was dedicated to the Maltese naturalist, Paul Sammut who is a keen specialist of butterflies and moths. Hyles sammuti is associated with open spaces where Spurge (Euphorbia) grows. Larval stages are known to feed on Euphorbia pinea, E. dendroides and E. spinosa. The caterpillar can be of two different forms, with white or yellow spots. The species is double brooded and adults fly during April and May and again during September and October. Adults are attracted to light and are sometimes a good source of food to geckoes and bats. This endemic species is widely distributed in the Maltese Islands and is afforded protection through the flora, fauna and natural habitat protection regulations of 2006. Aldo Catania

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caterpillar forms of H. sammuti

H. sammuti

Eggs of H. sammuti on Euphorbia 125

Brachytrupes megacephalus This relatively large cricket is a stenotopic species (adapts only to a narrow range of environmental conditions) belonging to the psammophilous biocoenoses, mostly inhabiting coastal sandy habitats  and desert locations within some parts of the Mediterranean, the Maghreb and Northwest Africa. Notwithstanding its considerable size, its nocturnal (crepuscular) habits and burrowing behaviour render it quite inconspicuous; had it not been for the highly noticeable stridulation by the male during the season of courtship (generally from the end of March to early June), this species would have been largely overlooked. Locally, Brachytrupes megacephalus was initially discovered at Ramla (Gozo) in 1955, and, twenty-two years later it was taken at Għadira in Malta. Subsequent research during the last three decades, brought to light important information about the species’ local distribution and, thus, revealed the existence of various other populations in coastal areas. Morphologically, the species is well adapted to burrow, using its large head to push loose sand as it excavates tunnels using the specialised tibia (armed with spurs) on the front and rear legs. Burrows measured in the Maltese Islands are relatively quite shallow when compared to counterparts in the Sahara desert, where some tunnels excavated by this species exceeded two metres. Although Brachytrupes megacephalus has a preference for sandy habitats, a population was recently discovered within the friable well-exposed quaternary conglomerates of the rdum formation along the L-Aħrax promontory. This demonstrates the species’ adaptive capacity towards establishing itself within a range of habitats, some of which quite uncharacteristic of the traditional sandy biotope. Nevertheless, its long-term survival depends on urgent pro-active conservation measures at different scales, notably, at species, habitat and landscape levels. This species is afforded protection through the flora, fauna and natural habitat protection regulations of 2006 and through the Habitats Directive of the European Union.

Louis F Cassar

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B. megacephalus stridulating

entrance to burrow of B. megacephalus

Ramla sand dune in Gozo 127

Viteus vitifoliae Viteus vitifoliae is a very small yellowish aphid, commonly known as Grape Phylloxera. The species attacks vines and originated in North America where the local vines evolved with it. In fact the American vine rootstalk has a very high index of resistance to the phylloxera, as the roots are very resistant to the pest and therefore it survives on it without much damage on the vines themselves. The species was accidentally introduced in Europe around 1860 from where it was then introduced to the Mediterranean basin, Middle East, Africa and Asia. In Italy, Grape Phylloxera was first detected in 1879 and one year later the species was also found in Sicily. For a long time, the Maltese Islands remained free from this pest but in July of 1919, a considerable infestation was detected in Ramla in Gozo (possibly through smuggling of grapevines from Sicily) and within one year the viticulture industry in Malta was almost completely destroyed. This aphid is able to attacks the roots of vines all year round where considerable damage can be done. Spherical, reddish galls (malformations) are formed on the leaf when this aphid attacks the upper parts of the plant. Once the vine is killed, the pest will search for other vines in the surroundings. Grape vines constitute an important agricultural commodity, and the Grape Phylloxera is a huge threat to this system. The only successful way of fighting this pest wherever it was introduced was through grafting of local vines on American rootstock which offer resistance to the pest. In Malta and Gozo, this pest is often met with on wild, non grafted vines showing characteristic leaf-galls. Erika Azzopardi

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Typical galls of Grape Phylloxera on wild vines

Ramla Bay in the 1920s 129

Apalus bimaculatus Apalus bimaculatus is a medium sized beetle, about 1 cm in length and widely distributed in the Palaearctic Region. It belongs to a group of insects commonly known as blister-beetles, on account of the chemical cantharidin, produced by the adults and which causes blistering of the skin. Another vernacular name for this group of insects is that of oil-beetles, which is derived from the fact that members of the genus Meloe, often excrete an oily substance from the joints of their legs when disturbed. The group is locally represented by eight species. The life cycle of these beetles is of great interest. The larvae are semi-parasitic predators, usually feeding either in the nests of wild bees on the larvae and food stores, or on the egg cases of grasshoppers. They are hypermetamorphic, that is, the first instar larva (known as triangulin) is active, while subsequent larval stages are sedentary. The triangulin larvae of those species parasitizing bees are phoretic and may be carried considerable distances by their host insect. The Maltese population of this species was described as a new variety, var. caruanae by the entomologist Joh Procházka in 1892 in honour of the Maltese Naturalist Count Alfredo Caruana Gatto who contributed tremendously not only in the field of entomology in Malta but also on other aspects of natural history. The ecology of this species is poorly known with adults usually found in maquis areas and in derivations of broadleaf and coniferous forests. Sometimes adults are also found on walls in disturbed areas, where possibly the host insect nests. In Malta, the species was always recorded in January and February possibly during cold days. A. bimaculatus is known to parasitize bees of the genera Anthophora and Colletes. Apalus bimaculatus was once a frequent species in the Maltese Islands with records in the early 1900s from Mosta, Naxxar, St. Paul’s Bay, Marsa, Marsaxlokk and Attard. Since then, no further records of this species were ever published. However, two specimens were collected in 1972 by Dr Martin Ebejer from Wied is-Sewda. If the species is not yet extinct from Malta, every effort should be done to conserve it and to do further research work so as to understand the affinities of the Maltese populations with those of mainland Europe. David Mifsud 130

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Apalus bimaculatus

Apalus bimaculatus mating Alfredo Caruana Gatto

Colletes bee emerging from nest

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