Abstract: The following paper contains a study of talitrid populations of two beach dune systems in Apulia (Lesina and Isola Varano), on the Adriatic coast of southern Italy. Two species were identified: Talitrus saltator and Macarorchestia remyi. Of the two populations, we concentrated on T. saltator, which is the most abundant species in the study area. However, M. remyi is worthy of mention, since it is the first record of an Adriatic population of the species. Bimonthly samplings were taken from August 2003 to July 2004 at Lesina and from January to December 2002 at Isola Varano. Abundances of talitrids were maximal in August at Lesina and in May at Isola Varano. Sex ratio was female biased at the two sites for T. saltator, whereas it did not differ significantly from equality in M. remyi. Mean zone level for each species was higher the shoreline in summer compared to cold months in the two localities.
Abstract: We describe here Haploginglymus morenoi n.sp. (Amphipoda Gammaridea Niphargidae) from the freshwater interstitial environment along Rio Mataraña, Beceite (Aragón), North-Eastern Spain. Sediment in the type locality is very fine-grained. Peculiar to the new species is article 6 of the maxilliped palp, which is spoon-like, with finely ciliated distal margin, rather than having the usual shape as a dactylus provided with a claw. Further diagnostic characters are provided by the sexually dimorphic gnathopods II and by the very elongated dactylus of pereiopods 6 and 7, whose claw is extremely short. One of the specimens of the type series is anomalous, in that its maxilliped has a pretty normal left dactylus, the right one being however shaped as in the other specimens of this species.
Abstract: The description of a new Ingolfiella of littoral interstitial water, the first finding among Ingolfiellidea for Philippines is presented. Male and female specimens are investigate and the new species seems close to the species group before included into the marine interstitial Tethydiella group. The new taxon shares a high number of features with I. xarifae Ruffo, 1966, described from Maldive Islands. The new species is characterized for the peculiar oosteogites morphology and for the presence in both sexes of spines and setae variously modified. Finally some data on species ecology and sampling sites are given.
Abstract: The distribution of three talitrid species-Talitrus saltator (Montagu, 1808), Orchestia gammarella (Pallas, 1766), Platorchestia platensis (Kroyer, 1845)-in the beach-dune system at the mouth of the Mignone River (central Italy) was analysed. It was related to the variations of the following abiotic factors: temperature, penetrability, pH, conductivity and moisture of the sediment. The beach-dune system is influenced by human impact and natural erosion. All species showed a maximum capture frequency in November, while the abundance decreased to a minimum in July. T. saltator was dominant on the beach, the other two along the riverbank. Juveniles were abundant along the riverbank; they were most abundant in November and almost disappeared in summer. T. saltator was more abundant near the waterline during the hottest months and occupied the inner beach in winter, with occasional presences on the dune. Regression analysis between the abiotic factors and species abundance showed a positive relationship with pH and temperature for T. saltator, while O. gammarella was negatively related to pH. Canonical correspondence analysis (CCA) showed that penetrability, moisture and temperature had the greatest influence on the species. T. saltator was almost entirely confined to the beach transects and strongly associated with penetrability, temperature and pH values. O. gammarella was mostly associated with the riverbank and P. platensis only found there and on a nearby pool. The two species were mainly influenced by moisture and variations in grain sizes of the sediment.
Abstract: We describe Caledonietta maryae n. gen. n. sp. based on material collected in New Caledonia. The new genus is similar to Phreatogammarus Stebbing, 1989 from New Zealand and distinguishable from it in the gnathopods 1-2 dactylus with 3 strong spiniform processes on disto-posterior margin, gnathopod 2 carpus without ventral lobe, and palmar margin of the propodus with few palmar spines.
Abstract: The bogidiellid amphipod crustaceans Stockigidiella aequimana new genus and species and Omangidiella parvidactyla new genus and species are described from subterranean groundwater habitats in the Sultanate of Oman on the Arabian Peninsula. Stockigidiella is easily distinguished by a row of long, deeply bifid setae on pereopods 5 and 6, whereas Omangidiella is distinguished by a greatly reduced propodus of gnathopod 2 and elongate oostegites; it also possesses a third coxal lobe on the maxilliped, a unique character noted only in three other bogidiellid genera from northern and eastern Africa. At present, the family Bogidiellidae contains 35 genera and 105 species but a significant number of provisionally recognized new species and possibly several new genera await description. The geographic distribution of the family Bogidiellidae is nearly circumglobal, but species tend to be clustered in discontinuous regions. A number of important questions regarding the origin and biogeographic history of the family remains unanswered.
Abstract: The Italian species of Niphargus belonging to the orcinus group are discussed and Niphargus cornicolanus n. sp. (from the Merro sinkhole, Sant' Angelo Romano, Cornicolani Mountains, Latium) is described. This species is morphologically well characterized (Ruffo T Vigna Taglianti, 1968). It is easily distinguished from N. parenzani (from the Alburni Mountains, Campania), to which it had been attributed (G. Karaman, 1993), and from N. patrizii (from the Ausoni and Lepini Mountains, Latium), mainly by the shape of Gn2. The distribution and relationships of the orcinus species group are discussed.
Abstract: Dispersal is a crucial phenomenon which has a strong influence on the ecology and evolution of species, determining the extent of gene flow among conspecific populations. In this paper, we present data on the degree of genetic structuring in 11 populations of the stonefly Dinocras cephalotes, focusing our attention on three Central Italian rivers: Aniene, Nera and Velino. We studied the genetic variation at 28 enzymatic loci by means of starch gel electrophoresis: 19 loci were polymorphic in one population at least. The degree of genetic structuring and levels of gene flow were estimated by F-statistics using WEIR & COCKERHAM'S estimators. Relatively high levels of genetic differentiation were revealed, considerably higher than those obtained in other studies of stonefly species. Neighbour-joining analysis provided a geographic scheme of relationships of the study populations, grouping them according to the river of origin. This analysis was supported by bootstrap values. We were not able to detect an unequivocal relationship between gene flow and geographic distances between sites within each river; this led us to hypothesise that equilibrium has not been reached between genetic drift and gene flow.
