Masato Moteki

Morphological characters and occurrence patterns of juveniles of two estuarine gobies, Acentrogobius kranjiensis and Acentrogobius malayanus, verified by molecular identification

Juveniles of two Acentrogobius species collected in a mangrove estuary in Sikao Creek, southern Thailand, were identified by morphological and molecular methods. A total of 1315 Acentrogobius specimens were collected and grouped into types A (n = 1107, 4.4-12.0 mm standard length, L(S)) (melanophore absent or indistinct on posterodorsal contour of caudal peduncle; two rows of melanophore blotches on lateral midline) and B (n = 208, 4.8-12.6 mm L(S)) (distinct melanophore on posterodorsal contour of caudal peduncle; a single row of melanophore blotches on lateral midline). Based on the reverse series method, the melanophore patterns of larger juveniles were linked with the smallest specimens possessing adult characters. The homogeneities of mitochondrial cytochrome b region sequences between the two juvenile types and adult Acentrogobius species collected in the study area indicated type A to be A. kranjiensis (homogeneity between type A and A. kranjiensis: 99.3-100%), and type B to be A. malayanus (homogeneity between latter 98.1 and 99.7%). No Acentrogobius juveniles were collected from the surf zone outside the creek mouth, both species apparently spending most of their life histories within the estuarine habitat. During their pelagic phase, A. kranjiensis and A. malayanus dispersed in the upper, middle and lower reaches of the creek. On the other hand, occurrence patterns during the benthic phase of A. kranjiensis and A. malayanus differed, the former showing upstream movement and the latter downstream movement with growth. These results emphasize the necessity of analysing early fish life histories at the species level, and the collaboration between morphological and molecular methods should prove valuable in accurately identifying of larvae and juveniles.

Developing Partnerships with the Community for Coastal ESD.

Purpose – The purpose of this paper is to draw lessons for developing community‐university partnerships from experiences in promoting coastal education for sustainable development (ESD).Design/methodology/approach – Qualitative data collected from two coastal community outreach projects were analyzed.Findings – The outreach projects improved the relationship between university and community members. It is important to conduct interviews at the early stages of the projects to understand the needs of the community and set project outcomes to meet community‐defined priorities. The most effective means for promoting an ESD program based upon community‐university partnerships is to reach out to and network with local individuals who have been active in community projects and embed the program concept into the activities of those individuals. Mediators who link the academic community with the local community are helpful in promoting the partnerships, and university students were found to be successful mediators...

Community structure of pelagic cnidarians off Adélie Land, East Antarctica, during austral summer 2008

Some studies have suggested that pelagic cnidarians are important components of the Southern Ocean ecosystem due to their high abundance and diversity and their high predatory effects, although little information on these animals is available. Thus, we examined the spatial distribution of pelagic cnidarians from the oceanic to neritic zone off Adélie Land, East Antarctica. Discrete depth sampling was conducted from the surface to 2,000 m depth from late January to early February 2008. In total, 3347 individuals representing 45 species/taxa from eight orders were collected. Cluster analysis revealed three major clusters: (1) an epipelagic group in the oceanic zone composed mainly of Pegantha martagon, the abundance and species diversity of which were very low; (2) a meso- and bathy-pelagic group characterised by high abundance and species diversity with dominance of Dimophyes arctica, Vogtia serrata, and Halicreas minimum; and (3) a neritic group represented by a high abundance of Diphyes antarctica. Cnidarian communities in the epipelagic zone were divided by hydrographic structures such as the Southern Boundary of the Antarctic Circumpolar Current and Antarctic Slope Front, whereas those in the meso- and bathy-pelagic layers dominated by circumpolar deep water were relatively stable with higher diversity throughout the oceanic zone.

Juvenile morphology and occurrence patterns of three Butis species (Gobioidei : Eleotridae) in a mangrove estuary, southern Thailand

Juveniles of three eleotrid Butis species (B. butis, B. humeralis, and B. koilomatodon) are described; their occurrence patterns were examined in Sikao Creek, a mangrove estuary located in southern Thailand. Juveniles of each species were distinguished by the following characters: B. butis with no bands on body and pale pelvic fins; B. humeralis with no bands on body and densely pigmented pelvic fins; and B. koilomatodon with 5–6 regular bands on body and a fleshy process (preorbital knob) on the snout. Although B. butis shared the aforementioned characters with B. amboinensis found in the same estuary, the former was distinguished from the latter by having a greater number of pectoral fin rays (18–21 vs. 17) and a deeper caudal peduncle. Distribution patterns of the three Butis species in Sikao Creek were distinguishable from each other. Smaller B. butis [mean ± SD = 22.7 ± 16.9 mm in standard length (SL), n = 32] occurred in the upper reach of the estuary, while larger specimens (52.4 ± 26.2 mm SL, n = 18 and 51.5 ± 29.7 mm SL, n = 10, respectively) were found in the middle and lower reaches and none in the marine area. In B. humeralis and B. koilomatodon, only juveniles were caught except for one adult specimen each. Juveniles (8.9–16.5 mm SL, n = 79) of B. humeralis occurred in the upper and middle reaches and the marine area. B. koilomatodon juveniles (9.9–13.7 mm SL, n = 30) were distributed in all areas from the lower to upper reaches.

Assemblage structures and spatial distributions of small gobioid fishes in a mangrove estuary, southern Thailand

We describe the assemblage structures and spatial distributions of juvenile and adult small gobioid fishes in a mangrove estuary in Trang Province, southern Thailand. The 11,183 gobioid juveniles and adults collected during the present study were classified into three families, 19 genera and 36 species. The three most dominant species were Pandakapygmaea, Acentrogobius kranjiensis and Acentrogobius malayanus, which accounted for 75.9, 15.0 and 3.8% of the total number of gobioids collected, respectively. Spatial differences in gobioid fish assemblages were found in a mangrove estuary and its adjacent marine area. The diverse gobioid fauna with a variety of lifestyles found at muddy-bottomed, low-salinity stations, which were mainly upper- and middle-reach stations, can be partly accounted for by the existence of the various microhabitats in muddy-bottomed areas around mangroves. These microhabitats may contribute to local fish catches because gobies are of great significance as prey species for piscivores, including commercially important fish in mangrove estuaries. The abundance of each gobioid species would contribute to the development of rational methods for assessing the effectiveness of mangrove conservation and rehabilitation programs.

Notes on the morphology of the early stage of the rare bramid genus Eumegistus

The morphology of the early stage of Eumegistus was described from three specimens [E. brevorti: 23.0 mm in standard length (SL) juvenile; E. illustris: 5.8 mm SL postflexion larva, and 40.0 mm SL juvenile] recently rediscovered in museum collections. Larval and juvenile pigmentation patterns were reported for the first time for this genus. The 5.8 mm SL postflexion larva of E. illustris had pigmentation on the head and anterior half of the body, through to the middle of the dorsal fin base. In larvae and juveniles of both species, the outer side of the pelvic fin was pigmented. The two juveniles possessed several spines on the lachrymal and protruding rays in the middle of the caudal fin. Although it is known previously that the notochord flexion occurs at 5.0–6.0 mm SL in E. brevorti, the reexamined 5.0 mm SL specimen had the notochord completely flexed. Furthermore, we could not confirm whether the previously studied 4.0 mm SL specimen was E. brevorti because it was badly damaged.

Distinctive characters between Eumegistus brevorti (Poey, 1860) and Eumegistus illustris Jordan and Jordan, 1922 (Perciformes: Bramidae)

The meristic characters for E. illustris and E. brevorti are summarized in Table 1. Eumegistus illustris shows dorsal fin rays 32–35, anal fin rays 23–26, pectoral fin rays 20–22, vertebrae 16–18 23–25 40–42, scales in horizontal series 43–53, scales above lateral line 14–19, scales below lateral line 14–15, predorsal scales 24–35, and total gill rakers 9–16. Meristics of E. illustris from the Southern Hemisphere coincide with those from the Northern Hemisphere, except in the number of scales above lateral line. Southern Hemisphere specimens had more scales above the lateral line than those from the Northern Hemisphere ones (18–19 News and Comments