• Fisheries and Aquatic Sciences
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• v.3 no.3_4
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• pp.180-187
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• 2000

Reproductive effort and spawning frequency of the two palaemonid prawns, Exopalaemon modestus and Palaemon gravieri, were investigated. In both embryos of the two species, egg size was larger in E. modestus than in P. gravien but for a given size, number of eggs (EN) was fewer in E. modestus. The statistical results revealed that there were significant differences in egg size and EN between the two species. E. modestus living in freshwater environments had larger and fewer offspring than P. gravieri inhabiting marine environments. These findings are consistent with predictions from r- and K-selections models. Reproductive effort (RE) also was higher in E. modestus, suggesting the possibility for E. modestus to invest larger amount of energy per individual offspring. In the two prawns the ovarian dry weight of females with eyed eggs was significantly higher than those with non-eyed eggs. This indicates that the ovarian maturation occurs during the period between the two embryonic stages, suggesting females being potentially of continuous breeding within a single reproductive period. In the both species brood loss did not occur during the incubation period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.198-202
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• 2006

We investigated the fecundity, egg size, reproductive output, and breeding frequency and season of Neocaridina denticulata denticulata and Latreutes planirostris which inhabit extremely different habitats. The marine shrimp Latreutes planirostris produced more eggs had at a given carapace length than the freshwater shrimp N. d. denticulata. However, N. d. denticulata had a larger egg volume and greater reproductive output than L. planirostris. The monthly gonadosomatic index (GSI) of the freshwater shrimp began to increase in April and reached a maximum in May, suggesting a single breeding period. In contrast, the GSI of the marine shrimp exhibited two breeding peaks: May-June and September. In both shrimps, the regressions between carapace length and ovarian weight were significant at the non-eyed and eyed embryo stages. For both species, an analysis of covariance revealed significant difference between the two regressions in elevation, but not in slope. These results indicate the potential for multiple ovulations within the reproductive season.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.456-460
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• 2018

Little is known about the movements of finless porpoises Neophocaena asiaeorientalis and their relationship with sea surface temperature (SST). A female finless porpoise that was stranded alive on the shore at Busan was rehabilitated for 16 months at the Sea Life Busan Aquarium. The porpoise was released off Geoje Island with a satellite tag on her mid-ridge and tracking data were received for 7 days. The porpoise moved directly to the southern shore of Gadeok Island, where an earlier study reported that finless porpoises were most abundant around the island. The tracking route revealed two other potential primary habitats. The porpoise moved to the middle of the east coast of the Korean Peninsula at Uljin, beyond the distribution boundary known from earlier studies. Satellite infrared images detected a cold water mass off the Uljin coast and the tracking route showed that the porpoise avoided this low-temperature area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.66-78
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• 2023

The sea hare Aplysia kurodai is an economic species located along the Korean coast. This study aimed to investigate the stomach contents of A. kurodai and its relationship with marine algal flora surrounding their habitat. A. kurodai and marine algae were sampled in seven and five areas in the East and the South seas, respectively. The marine algae found in the stomach and surrounding marine habitat were identified. In the East Sea of Korea, 134 species of seaweed were recorded. Thirty-nine species of marine algae were identified in the stomach contents of A. korudai collected from the East Sea of Korea. Seventy-five species of seaweed were collected in the South Sea of Korea. In addition, 26 species of marine algae were identified in the stomach contents of A. kurodai from the South Sea of Korea. Among the stomach contents of A. kurodai, ten sheet,12 filamentous, 27 coarsely branched, and one jointed calcareous form species were identified.

• Applied Microscopy
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• v.40 no.4
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• pp.237-244
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• 2010

Utricularia forms small, but complex carnivorous trap along the stem either in water or in soil depending upon species. The shapes and sizes of the traps, appendages, and trichomes are known to differ among aquatic, terrestrial and epiphytic species. In the present study, the morphology and microstructure of the trap in aquatic Utricularia japonica and terrestrial U. livida were examined using light and electron microscopy. The aim of this study was to compare the characteristics of trap features between the aquatic and terrestrial species. The trap was found to be comprised of a thin walled bladder with numerous capitate trichomes, two-armed bifid and four-armed quadrifid glands in both species; however, the traps of the two species were different in size, and number and morphology of the trichomes and glands. Aquatic Utricularia was chlorenchymatous with chloroplasts distributed throughout the body, whereas the terrestrial species was translucent without plastids due to an adaptation to underground habitats. Furthermore, the former differed considerably in that the traps developed antenna and appendages around the entrance area. A peculiar trap entrance was also noted in U. livida, which exhibited radiating rows of various trichomes within funnel-shaped tissue. A large number of glandular trichomes covered the entrance area and door surface with four trigger hairs each in the aquatic form but only two in the terrestrial form. The glandular trichomes near the door secreted a large amount of mucilage that temporarily composed the velum in the U. japonica, however, it was not observed in the terrestrial species. All of the aforementioned features were highly related in their structure and function during carnivorous mechanism in Utricularia. The current findings provide important data for further comparison of the different life forms within Utricularia.

• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.153-159
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• 2015

The oligochaete worms in the genus Nais are common to freshwater habitats. These worms have a highly-developed prostomium and pigmented eye spots. All species have hair chaetae, bifid or single pointed needle chaetae on the dorsal side and ventral chaetae beginning in II with bifid crotchets. Most species of Nais genus live in areas where bottom is covered by sand, gravel or organic matter in aquatic plants. Currently, 26 species of Nais have been recorded worldwide. From the recent faunal studies, 3 species of Nais have been newly reported in Korea. Here, we newly report 6 species of Nais with diagnosis, illustrations and identification keys to Korean Nais species: N. behningi, N. pseudobtusa, N. simplex, N. bretscheri, N. stolci and N. elinguis.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.10a
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• pp.155-156
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• 2003

The Coleoptera is one of the most species-rich order of animals, adapted to most terrestrial and freshwater aquatic habitats. Among them, the mulberry longicom beetle, Apriona germari Hope, is widely distributed in eastern Asia and became one of the major pests of mulberry tree in Korea. To obtain genetic information on the mulberry longicorm beetle, we have constructed cDNA library from the larvae whole-body. Here, we report Apriona germari ESTs profiles determined the 5'most end of 3072 clones. (omitted)

• ALGAE
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• v.23 no.1
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• pp.1-14
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• 2008

Forty-eight taxa of desmids belonging to Class Chlorophyceae (Order - Conjugales, Family - Desmidiaceae), collected from different aquatic habitats of Lalkuan, Kathgodam and Pantnagar areas of Uttaranchal state and Pilibheet district of Uttar Pradesh, which are regions of foothills of Western Himalaya, have been described. These taxa belongs to 5 genera viz. Closterium Nitzsch (6 spp., 5 var., and 2 forma), Euastrum Ehrenberg (1 var.), Staurastrum Meyen (2 spp., 1 var., 1 forma), Cosmarium Corda ex Ralfs (19 spp. and 10 var.), Pleurotaenium Naegeli (1 sp.). Staurastrum pseudopachyrhyncum Wolle (1884) is new record for desmid flora of India.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.441-441
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• 2002

In order to ensure a balance between economic development and a healthy Mekong Basin environment supporting natural resources diversity and productivity critical to the livelihood of its 65 million inhabitants, the Mekong River Commission (MRC) has been investigating the use of radar to remotely characterize and monitor the diversity, complexity, size and connectivity of the Basin's aquatic habitats. The PACRIM AIRSAR Mission provided an opportunity to evaluate the usefulness of radar technology to derive information for assessing, forecasting and mitigating possible cumulative and long-term impacts of development on the natural environment and the people's livelihood. This paper presents the results of mapping wetland cover types using multi-polarimetric radar for an area of the north-western corner of the Tonle Sap basin with data acquired from the AIRSAR Mission in September 2000. The implementation of a newly developed segmentation classification routine used to derive the image classification is described and the results of a fieldwork campaign to check the classification is presented.

• Animal Systematics, Evolution and Diversity
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• v.12 no.1
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• pp.17-24
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• 1996

Five hypotrichs inhabiting the representative aquatic and terrestrial habitats of Chindo Island, Strongylidium muscorum, Gonostomum affine, Histriculus cavicola, H. muscorum, Steinia quadrinucleata are discovered from Chindo Island. Of these, two species, Strongylidium muscorum Kahl, 1932 and Steinia quadrinucleata Dragesco and Njine, 1971 are newly recorded from Korea.