Terrestrial invertebrates - Udine Cultura

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102 oxygen, into a “blasting chamber” at the top of the abdomen when it is compelled to defend itself. The animal can thus produce tiny explosions, accompanied by a very hot spray which is directed at the aggressor. This phenomenon, which is easily observed, is recorded in the names of some species, such as B. explodens, B. sclopeta and B. crepitans. The Brachinus are also interesting for the unusual biology of their larvae, which develop as parasites on the pre-imago stages of other beetles. B. crepitans and B. explodens, for example, feed on the pupae of carabids of the genus Amara. Predators also include the many species of staphylinids, among which the eyecatching and often very abundant representatives of the genus Paederus stand out, and the characteristic Stenus, with their large protruding eyes and an extremely unusual extensible mouth apparatus. Phytophages dependent on hygrophilous plants include various chrysomelids, such as the small Galerucella pusilla which lives on Lythrum, the odd stubby Chrysolina, associated with Mentha, like Ch. staphylaea and Ch. polita, but most especially various, generally rare, species of the genera Donacia and Plateumaris, with their elegant and sleek shapes, the larvae of which develop at the expense of numerous aquatic or semi-aquatic plants. The weevils are also well-represented: on damp meadows, at some distance from the water, significant numbers of species may be found on plants of the knotweed family (Polygonaceae), such as Lixus linearis and L. bardanae, which have a Brachinus plagiatus preference for the genus Rumex, or some Rhinoncus, more frequently associated with Polygonum. Shorewards, the small species of the genus Nanophyes are frequent on Lythrum, of which the most common is N. marmoratus. Tapeinotus sellatus, which lives on Lysimachia, is a very infrequent species of unmistakable appearance, known only in a few sites in central-northern Italy. Instead, Mononchus punctumalbum is very common in the same environment, Cylindera trisignata and is easily observed on the flowers of its host plant, Iris pseudachorus, where it reproduces at the expense of the iris seeds. On hydrophytes, there is no lack of curculionids, capable of moving about on the water or of spending long periods submerged: examples are the tiny Tanysphyrus lemnae, whose larvae develop on duckweed, and the many species of the genus Bagous, generally rare and dependent on hygrophilous plants like Butomus and Sparganium or on true hydrophytes (Potamogeton, Ceratophyllum). Various species of anthicids live as saprophages or mycophages on damp soil. Some are ubiquitous, like Anthelephila pedestris, others rarer and more specialised, like Pseudotomoderus compressicollis and Tenuicomus velox bucciarellii - the latter described from specimens collected in the Veneto lagoons, but which has not been found for several decades. The small sylvanid Psammoecus bipunctatus is also probably mycophagous. It is rarely abundant, but is considered an indicator species of reed-beds. In brackish-water environments the number of species falls drastically. Among the carabids, the cicindelids or tiger beetles appear, hunting on bare ground during the hottest hours of the day. There are several halophilous species, some very common, such as Calomera littoralis nemoralis and Cylindera trisignata, others more localised, such as the Sicilian Cassolaia maura cupreothoracica. Among the most typical carabids of brackish soils are the pogonines, with the genera Pogonus, Pogonistes and Sirdenus (the last found only in Sicily and Sardinia), all halobious and at times with more than one species in the same site. They live on silty-clayey sediments, sometimes reaching as far as 103
104 the wet mud on the coastline, as in the case of Pogonus littoralis. Many species of Dyschiriodes also live in these environments. These small carabids have fossorial habits, and are often to be found in the burrows of the staphylinid beetles of the genus Bledius, on which they prey. Another burrower is the ground beetle Daptus vittatus, belonging to the group of the harpalines, which includes many granivorous species: among these is Staphilinid beetle of the genus Bledius also Anisodactylus poeciloides, which feeds on the seeds of Puccinellia. The staphylinid beetles characteristic of these environments include the previously mentioned Bledius, which are interesting both because of their morphology, the males having long prothoracic and cephalic horns, and their breeding habits, which involve the digging of tunnels in which the females accumulate small heaps of unicellular algae to serve as food for the newborn larvae. Indeed, these staphylinids betray their presence by their excavating work, the results of which are easily visible on the bare ground of sandbanks. Other staphylinids commonly found in glasswort communities are the small pselaphines, with many species including the halobious Brachygluta schueppeli, at times highly abundant. Many species of halobious anthicids belong to the community of ground-dwelling micro-coleopterans, in particular the genus Cyclodinus, together with the heterocerids, represented by species of the genus Heterocerus, in particular H. flexuosus, which has a limivorous (silt) diet. Phytophages are represented by a good number of haloxene species or only locally halophilous ones. There are not many specialised phytophages, but one, Chrysolina schatzmayri is of particular interest. It is endemic to the stretch of coast between Istria (beyond Trieste) and the Po Delta, where it develops on Inula crithmoides. It is associated exclusively with sandbanks, and is generally not very common, but numbers may at times be observed on the host plant, as happens with many phytophages. Highly localised, but with a wider overall distribution, is Bulaea lichatschovi, a pollenophagous coccinellid associated with Halimione portulacoides and perhaps other halophile Chenopodiaceae. There are also some halophilous species among the curculionids, such as the relatively abundant Asproparthenis albicans and the rarer and eye-catching Bothynoderes affinis, both associated with Chenopodiaceae. ■ Lepidopterans The lepidopteran fauna of damp environments is quite rich, being a direct expression of the floral diversity that characterises at least some of these sites. Butterflies include Lycaena dispar, a large lycaenid whose larvae develop on hygrophilous Polygonaceae. It is an uncommon species, in decline throughout Europe and protected by various international treaties (see also page 139). Many moths associated with reed-beds are also characteristic of freshwater areas, such as the cossid Phragmataecia castaneae, whose larvae live exclusively in reed stems, which they consume for up to two years prior to metamorphosis. It is a species with discontinuous distribution along the entire Italian peninsula, especially along the coastline. Many noctuids are also found in stands of reeds or cattails, such as species of the genus Archanara, never very common, whose larvae have endophytic habits, and some species of the genus Mythimna, the caterpillars of which consume leaves, such as those of the rare Simyra albovenosa and Senta flammea. Various pyralids, like Sclerocoma acutella and Chilo phragmitella, are also reed-eaters. There is a pyralid moth faunula associated with hydrophytes in stagnant waters containing plants with submerged stems and leaves. Acentria ephemerella, a very small species of unassuming appearance but of notable biological interest, lives on the latter. The females of Acentria may be of two different forms, one Lycaena dispar 105
Page 1 and 2: Terrestrial invertebrates MARCO ULI
Page 3 and 4: 96 ■ Molluscs The malacological f
Page 5: 100 ■ Heteropterans The typical h
Page 9 and 10: 108 ■ Dipterans The dipterans of
Page 11 and 12: Terrestrial vertebrates MAURO BON
Page 13 and 14: 116 117 Great crested grebe (Podice
Page 15 and 16: diver (Gavia arctica) and red-throa
Page 17 and 18: 124 Recent artificial environments:
Page 19 and 20: 128 aquatic birds, especially dabbl
Page 21 and 22: 132 Lesser white-toothed shrew (Cro
Page 23 and 24: agriculture and livestock farms sur
Page 25 and 26: 140 These environments are protecte
Page 27 and 28: Teaching suggestions MARGHERITA SOL
Page 29 and 30: 148 How to identify molluscs More t
Page 31 and 32: 152 RELINI G., BERTRAND J., ZAMBONI
Page 33 and 34: 156 Gibbula - 49, 52 Heterocerus -
Page 35: The authors wish to thank the follo

Terrestrial invertebrates - Udine Cultura

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