Comparing the effects of granivorous rodents on persistence of Indian ricegrass ( Oryzopsis hymenoides ) seeds in mixed and monospecific seed patches

In desert environments seeds are often heterogeneously distributed in small patches that vary in number of seed species and in seed density. Because seed harvest by rodents is often density dependent (a larger proportion of seeds is removed from high-density seed patches than from low-density patches), the proportion of residual or post-harvest seeds should be greater in low-density patches. In addition, seed preference can affect harvest. We tested whether the residual proportion of a highly preferred seed (Indian ricegrass, Oryzopsis hymenoides ) was less when in a seed patch with a 2nd species (mixed-species patch) than when in a monospecific seed patch. We predicted that the increased overall seed density due to the presence of 2 species in a patch would result in a lower residual proportion of ricegrass seeds in the mixed-species seed patches than in the monospecific patches. As predicted, the residual proportions of Indian ricegrass seeds were less each time ricegrass was paired with one of 6 other species in mixed-species patches. Similarly, the residual proportion of each of those 6 species was less when paired with ricegrass than when in a monospecific patch. We speculate on the potential implications of these results for the population dynamics of plant species and the physical structure of plant communities.     

New species and records of anthuridean isopod crustaceans from the Indian Ocean

Twenty four new species of anthuridean isopods are described from a variety of localities in the Indian Ocean, including the granitic Seychelles, Aldabra Atoll, Phuket Island, the Persian Gulf and Zanzibar Island: Family Antheluridae, Anthomuda quadrilineata; Family Anthuridae, Amakusanthura cosmoledo, Apanthuroides aldabrae, Apanthuroides calculosa, Eisothistos andamanensis, Eisothistos corallina, Heptanthura phuket, Malacanthura arabica, Mesanthura quadrata, Panathura indica, Pendanthura picardi, Pendanthura seminigra, Pendanthura siamensis, Quantanthura andamanensis; Family Hyssuridae, Neohyssura gladia, Xenanthura victoriae; Family Paranthuridae, Accalathura hastata, Accalathura phuketensis, Accalathura wardae, Leptanthura calcis, Leptanthura maheensis, Paranthura algophila, Paranthura seychellensis, Paranthura urodentata. Of the 15 genera represented, all except two were previously known from the Indian Ocean; Heptanthura and Pendanthura are recorded from the Indian Ocean for the first time. Most of the genera have wide distributions through the Indian, Atlantic and Pacific oceans, while the species tend to be endemic to limited island or coastal regions. The 15 genera are diagnosed and keys or comparative tables to the Indian Ocean species are provided.     

Dynamics of ostracod populations from shallow lakes of Patagonia: life history insights

Wetlands are one of the most valuable natural resources, providing a number of ecosystem services and socio-economic values. Small ponds sustain a rich aquatic biodiversity and because of their short hydrological regimen and small size are excellent environments for population studies of microcrustaceans such as ostracods. This study describes the population dynamics of the Ostracoda fauna in three temporary shallow lakes during one hydroperiod in Argentine Patagonia. Three cosmopolitan species were determined: Cypris pubera, Tonnacypris lutaria and Eucypris virens. Among them, T. lutaria is here reported for the first time from the Neotropical region. Multivariate ordination techniques were used to examine the relationships among environmental variables and ostracod density on each sampling site. High values of conductivity, absorption at 320 nm (as a measure of dissolved organic matter), dissolved oxygen concentration, temperature and chlorophyll a concentration correlated positively with ostracod density. All the populations studied reproduced parthenogenetically, and the life cycles of E.virens and C. pubera were followed in detail by weekly sampling of their populations. The former displayed continuous reproduction, whereas the latter showed a multivoltine strategy. The life history of C. pubera was affected by the seasonality of the habitat. The development rate correlated positively with water temperature; conductivity and temperature had a positive effect on adult size in C. pubera, while conductivity had a negative effect on adult size in E. virens. In this study, we present the first data set on the development and life history of ostracods in Patagonian freshwater environments. However, several questions remain and encourage us to further investigate the relative importance of ostracods in food webs, as well as the importance of inter-specific interactions between ostracods and other taxa.     

On the species of Stemonocera Rondani (Diptera: Tephritidae) from the Indian subcontinent

A new tephritid species from Pakistan, Stemonocera longisystylis sp. nov. Singh, Hancock & Ramamurthy is described and Stemonocera cervicornis (Brunetti) is redescribed with details of external morphology including genitalia and sexual dimorphism. A new combination Acidiostigma discale (Brunetti) is proposed for Acidia discalis Brunetti, previously included in Stemonocera.

http://zoobank.org/73F6BC90-8699-4C0A-9BA7-45349D32A8C3     

A new species of stoloniferous octocoral (Cnidaria: Alcyonacea) from the south-western Indian Ocean

A new species of stolonate octocoral referable to the genus Scleranthelia Studer, 1878 (family Clavulariidae), is described from the East London and Durban regions of South Africa. The species is frequently encountered by dredge at depths ranging from 85 to 340 m. Scleranthelia thomsoni sp. nov. has been confused with the northern Atlantic species S. rugosa (Pourtalés, 1867) (= S. musiva Studer, 1878) by previous authors, but a comparison of material representing both species has shown them to be distinctly differentiated.     

A new genus and two new species of cirolanid isopod Crustacea from the northern Indian Ocean

A new genus of cirolanid isopod Atarbolana, and two new species, Atarbolana exoconta and Cirolana manorae, are described. Atarbolana is distinguished from related cirolanid genera by having a projecting clypeus, pleon with three free tergites, and cylindrical uropod exopod.

Cirolana manorae is most similar to Cirolana bovina Barnard, and new figures are given for that species.     

New species and records of Asellota from the Indian Ocean (Crustacea: Peracarida: Isopoda)

In this study of asellote Isopoda from the Indian Ocean, 29 species in 11 genera and seven families are recorded. Twenty-one species are described as new: family Gnathostenetroididae, Maresiella aldabrana ; family Janiridae, Carpias mossambica ; family Joeropsidae, Joeropsis algensis, J. arpedes, J. dimorpha, J. hamatilis, J. lentigo, J. pentagona, J. pleurion ; family Pleurocopidae, Pleurocope wilsoni ; family Pseudojaniridae, Pseudojanira meganesus ; family Santiidae, Santia spicata, S. urospinosa ; family Stenetriidae, Hansenium aldabrae, H. expansa, H. remocarpus ; Mizothenar serratum, Stenetrium assumentum, S. quinquedens, S. zanzibarica, Stenobermuda brucei. The first record of the family Pleurocopidae (Pleurocope wilsoni) and the genus Mizothenar (family Stenetriidae) from the Indian Ocean are included. Diagnoses of the genera and species are provided, and keys to the Indian Ocean species of most of the genera. The material comes primarily from Aldabra Atoll, the granitic Seychelles islands, Zanzibar Island, the Comoro Islands, and Phuket in Thailand. A few samples are from material of the International Indian Ocean Expedition carried out in the mid-1960s.     

New species and records of Flabellifera from the Indian Ocean (Crustacea: Peracarida: Isopoda)

In this study of flabelliferan Isopoda from the Indian Ocean, 19 species are described as new, in 11 genera and two families: family Cirolanidae, Baharilana koloura, B. lira, Cirolana aldabrensis, C. mimulus, C. somalia, C. undata, Eurydice paxilli, and Metacirolana chemola; family Sphaeromatidae, Cassidinidea clarkae, Cymodoce fuscina, C. lirella, Dynamenella alveolata, D. remex, Heterodina (new genus), H. mccaini, Oxinasphaera brucei, O. furcata, O. tetrodon, Paracilicaea stauros, and Sphaeromopsis sulcifera. Diagnoses of the genera and species are provided, and keys to the Indian Ocean species of most of the genera are provided. The material comes primarily from Aldabra Atoll, the granitic Seychelles islands, Zanzibar Island, and Phuket in Thailand. A few miscellaneous samples from the South African Museum collections, and from the International Indian Ocean Expedition carried out in the mid‐1960s are included.     

Decapod Crustacea from the International Indian Ocean Expedition (Larval and post-larval stages of Parapenaeus Smith (Penaeinae)

Summary

Developmental stages of Parapenaeus investigatoris Alcock and Anderson from second protozoea to late post-larva and an incomplete series of P. longipes Alcock and P. fissurus (Bate) are described and figured. Important generic characters of the larvae of Parpaenaeus are two pairs of supra-orbital spines in the protozoeae, a strong hepatic spine, a long dorsomedian spine on the third abdominal segment, ventromedian spines on the anterior abdominal segments and sometimes on the last thoracic segment, a pair of dorsolateral spines on the fifth and sixth abdominal segments and a median spine on the telson.

The species recorded are widely distributed in the northern Indian Ocean, particularly in the Bay of Bengal, but only two specimens were taken south of the Equator and few in the more open parts of the ocean.     

Decapod Crustacea from the International Indian Ocean Expedition: The species of Funchalia (Penaeidae) and their post-larvae

Summary

Information is sparse on the ecology of the larval and juvenile stages of the lobster (Homarus gammarus (L.)). A knowledge of the distribution and particularly the abundance of this species is vital for the development of stock-recruitment theory. Attempts were therefore made to determine the distribution of juvenile lobsters in the field by Scuba diving and the fishing of small mesh traps.

As these initial attempts were of very limited success, lobsters were reared in the laboratory to study their substrate preferences and behaviour. Juvenile lobsters (～8 mm carapace length) selected coarse substrates which offered suitable crevices, or burrowed extensively in fine, cohesive mud. The rock crevice habitat is widely used by adult lobsters, but the construction of complex mud burrows has not previously been described for this genus. The burrowing behaviour of juvenile lobsters and the structure of the burrows are discussed. Juvenile lobsters appear to have wide habitat tolerances enabling them to inhabit a variety of substrate types. The estimation of juvenile lobster abundance is likely to be extremely difficult.     

Reproductive characteristics of Elaphe quadrivirgata (Serpentes: Colubridae) from ecologically dissimilar main island and island populations

We compared reproductive characteristics of a snake (Elaphe quadrivirgata) from two geographically distinct populations, which differ considerably in habitat use and diet. Snakes in Shiga Prefecture, in the central western area of the main island of Japan, occupy open rice fields and predominantly eat frogs. Snakes on Yakushima Island, in southwestern Japan, occupy a forest environment and mainly eat lizards. Maternal body size of snakes from Yakushima was significantly smaller than that of snakes from Shiga. Oviposition date was significantly later in snakes from Yakushima than in those from Shiga, and the former laid a smaller number of considerably elongated eggs than the latter. Relative clutch mass was significantly higher in the Shiga than in the Yakushima population, but egg mass in relation to maternal body mass of the latter was larger than that of the former. Hatchlings of Yakushima were larger than those of Shiga. This size difference in hatchlings was not fully explained by differences in egg size. These differences in reproductive characteristics between the two populations do not seem to be a consequence of morphological constraints of dam snakes. Instead, we presume that the differences in reproductive characteristics reflect local adaptations.     

Morphological and genetic variation among populations of the rare Kachina daisy ( Erigeron kachinensis ) from southeastern Utah

Erigeron kachinensis , the Kachina daisy, is a rare species restricted to canyons in southeastern Utah. The species is known to exhibit low fecundity due to low percent fertilization of ovules and high percent abortion of fertilized ovules. Previous reproductive studies suggest that low fecundity is a consequence of small population size and inbreeding depression. This study examines genetic diversity within and among populations of E. kachinensis in Natural Bridges National Monument using enzyme electrophoresis. Field populations are found to have significantly different morphologies. However, morphological differences were less pronounced among populations grown in the greenhouse. The Kachina daisy exhibits levels of genetic variability in its populations similar to that of other outcrossed species. Genetic diversity statistics demonstrate that only 22.8% of genetic variation is distributed among populations. Genetic distance could not be correlated with geographic distance. Most of the populations showed significant deviation of fixation indices from zero for multiple loci. Observation of genotype frequencies demonstrates that populations are fixing on different genotypes and may be experiencing initial stages of genetic drift. Mean observed heterozygosity was 0.166 and was found to increase with increasing size and/or age in populations.