Larval development of Capitulum mitella (Cirripedia: Pedunculata) comprises six nauplius stages and a cyprid. Unilobed labrum, a larval trait of pedunculate and chthamalid barnacles, bears two groups of slender hairs and two pairs of strong teeth on the distal labral margin, and a pair of teeth on the lateral labral margin. Frontolateral horns extended under the anterior cephalic shield margin are diagnostic features through all nauplius stages. The posterior border of the cephalic shield bears a pair of distal cephalic shield spines in nauplius stages II and III, and a pair of long posterior shield spines in nauplius stages IV, V and VI. A hispid seta is consistently found at the fourth group of the antennal endopodite through stages II–VI. The dorsal thoracic spine, abdominal process and the paired posterior shield spines have numerous small spines. Morphological features such as the cephalic shield, labrum, abdominal process, antennules, antennae and mandibles in all nauplius and cyprid stages are illustrated and described. In this species, the numerical setations of the antennule are found to be beneficial for intra-specific identification of barnacle nauplius stages without the need for dissection.

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Membranobalanus koreanus is a sponge barnacle inhabiting the pumpkin-coloured sponge, Cliona celata, which is attached to rocky bottoms. The larval morphology is described and illustrated for the rst time from larvae reared in the laboratory. Size and setation formulae are given for each larval stage. Total length, shield width, setal type of the 4th segment of the antennal endopodite, morphology of the labrum, and cephalic shield spine in stages IV-VI, and setation involving the number, relative location, and types of setae on appendages such as antennule, antenna and mandible would be useful in the identi cation of the barnacle larvae. In addition to the above morphological features, patterns and number of the thoracic spines are found to be useful in both the intraspeci c and interspeci c identi cation of barnacle larvae. Morphological differences between the larvae of M. koreanus and Acasta spongites, both inhabiting the sponges, are minor. RÉSUMÉMembranobalanus koreanus est une balane spongicole habitant Cliona celata, éponge xée sur des fonds rocheux. La morphologie larvaire est décrite pour la première fois d'après des larves élevées en laboratoire. La taille et les formules sétales sont données pour chaque stade. La longueur totale, la largeur du bouclier, le type sétal du 4ème article de l'endopodite antennaire, la morphologie du labrum et l'épine du bouclier céphalique aux stades IV-VI, ainsi que la sétation, avec le nombre, la position relative et les types de soies sur des appendices tels que l'antennule, l'antenne et la mandibule peuvent être utiles dans l'identi cation des larves de balanes. En plus des traits morphologiques ci-dessus, la disposition et le nombre des épines thoraciques sont utilisés dans l'identi cation intra-et interspéci que de ces larves. Les différences morphologique s entre les larves de M. koreanus et d'Acasta spongites, habitant l'un et l'autre ces éponges, sont mineures. c ® Koninklijke Brill NV, Leiden, 2000 Crustaceana 73 (4): 393-406

Patinopecten yessoensis is known to be farmed only in the northern part of the East Sea today. In an attempt to extend its production area, we have conducted experiments both in the northern and southern parts of the East Sea and studied on their growth in an aim to use the results for increasing overall productivity of the species. Early juvenile scallops producted in February 2014 showed an average shell length of 0.23 ± 0.002. The high growth group showed an average shell length and shell height of 4.11 ± 0.08 mm and 4.28 ± 0.09 mm, respectively, in June while they were 23.63 ± 3.4 mm and 24.19 ± 4.5 mm in October. The low growth group showed an average shell length and shell height of 2.23 ± 0.7 mm and 1.99 ± 0.9 mm, respectively, in June while they were 17.06 ± 3.4 mm and 17.59 ± 4.5 mm in October. The daily growth rate of the high growth group was 0.037 mm/day and 0.027 mm/day for the low growth group. In August, we measured the shell length of Patinopecten yessoensis from Yangyang-gun, Gangneung-si, Yeongdeok-gun, and Pohang-si. Patinopecten yessoensis from Pohang-si showed the best growth performance with its shell length of 26.90 ± 3.6 mm. Patinopecten yessoensis from Yeongdeok was the second largest with its shell length of 23.56 ± 3.4 mm. We presume that optimal water temperature and phytoplankton abundance of the two regions have contributed to the good growth performance of the species.