Systematic Study of Korean Formica Ants Using RAPD

ABSTRACT The phytogeny of Formica ants in Korea was carried out using RAPD. Analyzing RAPD marker, the similarity degrees between species were estimated, and they were compared with the results from the measuring values of thirteen morphological characters. Morphological analysis showed as follows: all the five species were grouped with 72% or more similarity. Out-group, Camponotus was independently isolated. F. lemani and F. Candida, F. yessensis and F.japonica were grouped in a very tight cluster with 97% or more similarity, while F. sanguinea+F. yessensis and F.japonica were grouped with 88%. On the other hand, RAPD analysis showed as followes: F. sanguinea, F. yessensis were grouped at the level of 97% similarity, F. lemani and, F. Candida were also grouped with 97%. Both two groups were again grouped with 85% or more. This group and F.japonica were grouped with 72% similarity. In RAPD the lowest similarity was 72% in the five species of Formica. The positional homology of amplified fragments was identified by Southern hybridiztion of RAPD fragments. As a result, F. sanguinea and F. yessensis showed 97% degree of similarity, and also F. lemani and F. Candida showed 97%. F.japonica and above four species showed 72%. The level of similarity of F.japonica against the other four species was lower than those of four other species.     

Local adaptation of developmental time and starvation resistance in eight Drosophila species of the Philippines

The ecological trade-off between developmental time and starvation resistance, acting in a heterogeneous environment, can promote the coexistence of competing species. Heterogeneity results from variation in the vegetation that influences both abiotic (e.g. temperature, humidity) and biotic (e.g. fruit availability during the year) aspects of the environment. In this study, we investigated whether differences between collection sites have led to local differentiation of the two life-history traits underlying the coexistence model: developmental time and starvation resistance. Drosophila were collected from four collection sites, ranging from grassland to secondary forest, along a transect of 15 km. The microclimatic and vegetation differences among these collection sites were considerable. For developmental time, different species showed similar genetic responses to the (habitat) differences between the different collection sites. The shortest developmental times were found in the secondary forest populations and the agricultural area populations, the longest in the grassland populations, and the forest edge populations were intermediate. However, there was no correlation between the habitat ranking based on disturbance and canopy cover, and the ranking of the developmental times. Furthermore, the data did not confirm the generality of the positive correlation between developmental time and starvation underlying the coexistence model.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 87 , 115–125.     

Taxonomic Review of the Family Lycidae (Coleoptera) in Korea

We reviewed the family Lycidae in Korea. The Korean Lycidae was recorded to fourteen species under eight genera until now. However, the taxonomy of Korean species was conducted without comparative analysis. We revised the Korean Lycidae to eleven species under seven genera of two subfamilies. Also, we provided the key to subfamilies, gernera, and species including illustrations of pronotum and aedeagus, the photos of adult habitus.     

Contribution to the Tribes Diaperini Doyen in Korea (Coleoptera: Tenebrionidae: Diaperinae)

A taxonomic review of six genera of Korean Diaperini is presented. Seven species in Korea are described here. We provide a key to the Korean species and genera, diagnoses and photos for them.     

Food webs in tropical Australian streams: shredders are not scarce

1. Macroinvertebrates were collected in dry and wet seasons from riffles and pools in two streams in tropical north Queensland. Total biomass, abundance and species richness were higher in riffles than in pools but did not differ between streams or seasons. 2. Gut contents of all species were identified. Cluster analysis based on gut contents identified five dietary groups: I, generalist collectors; II, generalist shredders and generalist predators; III, generalist scrapers; IV, specialist shredders; and V, specialist predators. Species were allocated to functional feeding groups (FFGs) based on these dietary groups. 3. Many species were generalist in their diets, but specialist predators and shredders were particularly prominent components of the invertebrate assemblages in terms of biomass and species richness. 4. Community composition (proportions of biomass, abundance and species richness of the different FFGs) varied between habitat types, but not between streams or seasons, although differences between riffles and pools varied with season. 5. Comparison of the fauna of 20 streams showed that our study sites were similar to, or not atypical of, low‐order streams in the Queensland wet tropics.     

Evidence for non-random spatial positioning of migrating smolts (Salmonidae) in a small lowland stream

1. The ontogenetic development of anadromous salmonids includes downstream emigration of immature individuals from freshwater towards the marine environment. Although this migration of juvenile salmonids (smolts) may be associated with severe mortalities, only limited attention has been paid to the spatial positioning of smolts in small streams. 2. Using a novel approach, this study examined the vertical and horizontal positioning of brown trout and Atlantic salmon smolts while performing downstream migration in a small lowland stream. 3. Pre‐smolts of indigenous and hatchery‐reared (F1) brown trout (Salmo trutta), and two different populations of Atlantic salmon (S. salar), were tagged with passive integrated transponder (PIT) tags and subsequently released upstream of an antenna array consisting of five circular swim‐through PIT antennas. Antennas were positioned in order to determine whether the migrating smolts were bottom or surface oriented, and if they were oriented towards the mid‐channel or the stream bank. 4. During the smolt emigration period, data describing both the detection of the migrating fish and the amount of water passing through the antennas were collected. This was accomplished in order to determine if the fish were performing active positioning behaviour independently of the vertical and horizontal discharge distributions in the stream. 5. The results showed that the smolts migrated in a non‐random spatial pattern independently of the stream discharge distributions. Vertically, the indigenous brown trout and the Atlantic salmon demonstrated a preference for the bottom orientated positions. In contrast, the distribution of the F1 brown trout was not different from the discharge distribution. The latter observation suggests random vertical positioning, which may be indicative of inferior migratory performance. Horizontally, all tested smolt populations strongly preferred the mid‐channel positions. 6. The discharge‐corrected preferences for certain spatial positions suggest that smolt emigration is not entirely a matter of passive displacement in lowland streams. 7. Anthropogenically altered channels may inhibit or delay downstream emigration of smolts resulting in increased mortalities. Given that the smolts in this study actively selected spatial positions in the mid‐channel and near the bottom, it is suggested that deep, mid‐channel furrows may be used to help guide migrating smolts past adverse habitats in lowland streams.     

Cold hardiness in the black rice bug, Scotinophara lurida

Abstract.  The mechanisms and strategies for winter survival of the black rice bug Scotinophara lurida are investigated along with the relationship between cold hardiness and diapause. The ability of S. lurida to survive subzero temperatures varies depending on developmental stage, temperature and exposure duration. Mean supercooling point (SCP) varies from –7.6 to –10.7 °C with developmental stage, but is not significantly different between stages examined. The SCP also varies with season, being lowest in January and increasing rapidly in February and remaining almost at the same level (–7.3 to 9.6 °C) until April The osmolality of haemolymph of field-collected S. lurida adults rises dramatically from 53.9 mOsm kg⁻¹ in August to 75.3 mOsm kg⁻¹ in December, and then declines linearly to 57.0 mOsm kg⁻¹ in May. Field-collected S. lurida adults show a peak glucose content in October, glycerol content in November and trehalose content in December. Only trehalose content decreases after the application of the juvenile hormone analogue, fenoxycarb, suggesting that trehalose is a cryoprotectant during diapause. These various physiological and biochemical traits related to cold tolerance in S. lurida may be, at least in part, under the control of juvenile hormone through the reproductive diapause programme.