Branchipus cortesi n. sp.: a new anostracan from western Spain (Crustacea,Branchiopoda)

Branchipus cortesi, n. sp. (Anostraca, Branchipodidae) is characterized by the broadly enlarged distal segments of male antenna 2, and a combination of morphological features concerning thoracic limbs, abdominal segments and egg morphology. The species occurs in temporary fresh water bodies in flatlands with temperate Mediterranean climate; it is distributed in the south-western part of Spain. Our study includes a morphological analysis using optical and scanning electronic microscopes. Questions about ecology and distribution of the new species are also discussed.     

Photosynthesis of Gelidium sesquipedale: effects of temperature and light on pigment concentration,C/N ratio and cell-wall polysaccharides

Tanymastix stagnalis is known from seven locations in Ireland. These range from small to large temporary water bodies. It was earlier shown that the best hatching and survival of eggs and young stages occurred in the presence of soil and at temperatures between about 10° and 15°. Some eggs hatched after one drying period, others after up to at least 4 drying and wetting periods. It was found from field observations that the habitat appeared after a minimum of 200 mm of rain in a 2-month period. This occurred on average more than once per year, mostly between June and February. A computer model was constructed using field data, and meteorological data (rainfall and temperature) covering 100 years, to decide how secure the organism was in two contrasting habitats. This showed that in both habitats there was little likelihood of extinction from metorological causes. There was, however, the possibility of destruction of the smaller habitats either through drainage or conversion to permanent ponds through compaction of the soil by heavy farm animals. The distribution and the possibility of harvesting the organisms is briefly discussed.     

Horizontal distribution and abundance of cysts of several large branchiopods in temporary pool and ditch sediments

Cysts of three species of anostracans (Branchipusschaefferi, Chirocephalus diaphanus, and Tanymastigites perrieri), two species of Notostracans (Triops numidicus and Lepidurus apus) and one species of Spinicaudata (Leptestheriamayeti) were collected from the upper 2 cm of dry sediments at intervals along transects from a temporary pool in an arid zone of Morocco and from two ditches in France. The horizontal distribution of viable cysts was patchy and is discussed in relation to several ecological parameters prevailing during the aquatic phase. These include vegetation distribution, depth and morphometry of the pond, dominant wind pattern, and granularity of the sediments. The densities reached more than 1700 cysts of C. diaphanus per 100 cm², and 1150 cysts of L. apus per 100 cm² in the two ditches. The mean densities of cysts per 100 cm² calculated for each transect ranged from 250 to 450 for C. diaphanous and 240 to 260 for L. apus (in the ditch populations) and about 1–6 for T. perrieri and L. mayeti, 3–15 for B. schaefferi, and16–58 for T. numidicus in the pool in Morocco. This revised version was published online in August 2006 with corrections to the Cover Date.     

The status of Anostraca,Notostraca and Conchostraca (Crustacea: Branchiopoda) in Yugoslavia

The investigations of Anostraca, Notostraca and Conchostraca in Yugoslavia began after a great delay compared with other European countries. Intensive systematic investigations date back only to the 1970s.To date, 19 species have been recorded. All species, with the exception of Artemia salina, are faunal elements of the Pannonian region. Seven species, including Artemia salina, Branchinecta orientalis, Branchipus serbicus, Leptestheria dahalacensis, Limnadia lenticularis, Imnadia cristata and Imnadia panonica are known from single localities. Six species including Branchinecta ferox, Chirocephalus brevipalpis, Chirocephalus carnuntanus, Lepidurus apus, Eoleptestheria spinosa and Imnadia banatica have restricted distributions. Streptocephalus torvicornis and Cyzicus tetracerus are known from several localities, while Branchipus schaefferi, Chirocephalus diaphanus, Triops cancriformis and Leptestheria saetosaare common. Large branchiopods are mainly confined to anthropogenic landscapes, especially in the northern part of the country. Rare species inhabiting a single pond, or those with rather restricted distributions, are the most endangered and such species account for about 70% of the fauna. Limnadia lenticularis, Imnadia cristata and I. panonica have not been found for more than 20 years and they are probably extinct in Yugoslavia. Branchipus serbicus, Imnadia cristata and panonica have not been documented since being originally described. Eoleptestheria spinosa is currently the most endangered species since it only appears irregularly in small populations. At present, Branchinecta ferox, Chirocephalus carnuntanus and Imnadia banatica are the safest of the rare species as they regularly appear in large numbers. There are no large branchiopods on the List of protected animals in Yugoslavia. This revised version was published online in August 2006 with corrections to the Cover Date.     

Observations on the biology of the rare Branchipus visnyai Kertesz 1956 (Crustacea, Anostraca) from Monti Reatini (Latim, central Italy)

Branchipus visnyai is presently known from only one location, in Italy, on Monte Catabio (central Appennine, Latium, 1590 m a.s.l). It lives in a large astatic pond and in a small temporary pool close to the pond. Typically two generations appear in the pond (in spring after snowmelt and in autumn after dilution by rainfall), unless an exceptionally dry season occurs. Yet, due to shallowness and small size, filling and duration of the pool is erratic and depends on the annual amount of snow and rainfall. Consequently, B. visnyai does not always appear in the pool.Field studies suggest that either a rise in temperature or a drop in conductivity may trigger cyst hatching in the two biotopes. Also, the species exhibits a high tolerance to change in environmental factors like water temperature. Hatching occurs within a range of 10–22 °C, adults survive at temperatures from 1 to 27 °C. The optimum seems to correspond to 10–20 °C.     

Concerning the identity ofBranchinecta santacrucensis César, 1987

The type series of the speciesBrachinecta santacrucensis César 1987, is compared with specimens ofBranchinecta granulosa Daday 1902 collected near Facundo, Chubut Province, Argentina. The great resemblance between them suggest that both sets of material belong to the same species and therefore,B. santacrucensis andB. granulosa are synonyms.     

Streptocephalus caljoni n.sp. (Crustacea: Anostraca) from Burundi and analysis of its limb structure

Streptocephalus caljoni n. sp. from Burundi is described. It is related to Streptocephalus trifidus, but differs from it and other Streptocephalus in the cheliform hand of the male antenna II. We also analyse the morphology of the setae on the endo- and exopodite of the fifth trunk limb, using light- and scanning electron microscopy. This analysis reveals additional differences between the two related species, and is a useful tool in the study of the taxonomy of the Anostraca.     

Anostracan cysts found in California salt lakes

The salt lakes of California are home to four genera and eight species of Anostraca. The cysts of most of these species are readily distinguished using a combination of cyst and geographic characters. Cyst identification is a valuable tool that can allow a look at fairy shrimp ecology when adults are not available. For example, fossil anostracan cysts from 500-year-old Mono Lake sediments show more character variation than currently exists in extant Artemia monica, indicating a greater diversity of Anostraca at that time. Continuing desertification, both natural and man-made, in the Mono Lake area over the last 500 years is associated with decreased diversity in the Mono Lake anostracan fauna.     

Supplement to " checklist="" of="" the="" anostraca""="

Our 1995 "Checklist of the Anostraca" covered all species described through 31 December 1993 along with those described in the volume from the Second International Large Branchiopod Symposium (Hydrobiologia 298). This supplement includes new species (14) described through 31 December 1996, one change in rank and one new species discussed in this symposium volume, anew synonym, and correction of errors discovered in the original. We do not update new range extensions. With these additions and changes, we number the named anostracan fauna of the world at 273 species and six subspecies organized in 23 genera. The need for more study of anostracan zoogeography is again demonstrated by the fact that seven of the 16 species added to the checklist are know only from their type localities. Until we have more complete information on the distributions of the species, it will not be possible to make an accurate evaluation of the status of anostracan biodiversity. This revised version was published online in August 2006 with corrections to the Cover Date.     

Branchiopods (non-cladocerans) of the Maltese Islands (central Mediterranean)

Four branchiopod species occur on the Maltese Islands, viz. Branchipus schaefferi, B. visnyai, Cyzicus tetracerus and Triops cancriformis. All four live in freshwater pools, but it is noteworthy that, beside B. schaefferi, T. cancriformis was recorded from a mesohaline, coast-fringing habitat.