Chthamalid barnacles may be highly affected by environmental factors as they Uve in the upper intertidal zone, where other balanids cannot hve due to the harsh conditions of the habitat. This study presents some information on the effects of temperature and food availability on the growth and moulting rates of a chthamalid barnacle, Microeuraphia permitini (Zevina & Litvinova, 1970) of the subfamily Euraphinae. Growth and moulting rates were estimated at different temperatures (20, 25 and 30°C) and food concentrations (6, 12 and 25 Artemia ind~' day^'). The results indicated that growth rate generally increased at 12 and 25 Artemia ind~' day"' compared \.o6 Artemia ind~' day"'. Further, the highest growth rates of 0.32 ± 0.02 (% RCD/day) and 0.35 ± 0.01 were observed at 30°C when barnacles were fed with 12 and 25 Artemia ind~' day"', respectively. Results of a two-way analysis of variance indicated temperature and food concentrations have a combined positive effect on growth (F = 3.1, P = 0.02) and moulting (F = 3.9, P = 0.01) rates of the species. The food concentration in particular has a major effect on growth and moulting activities; whereas the effect of temperature was minor and limited to increased feeding rate, which may be a result of increasing vital activities including rate of cirral beating. Continued observations noted a reduced growth rate before maturity of the specimens, which can be attributed to a loss of tissue as egg masses. RESUMELes balanes Chthamalidae, du fait qu'elles vivent dans la zone intertidale supérieure, où d'autres balanes ne peuvent pas vivre à cause des rudes conditions de cet habitat, peuvent être affectées par des facteurs environnementaux. Ce travail présente des informations sur les effets de la température et de la disponibilité de l'alimentation sur la croissance et le rythme des mues d'une balanê ) 642 RAZIEH SAVARI ET AL.Chthamalidae, de la sous famille des Euraphinae, Microeuraphia permitini (Zevina & Litvinova, 1970). La croissance et le rythme des mues ont été estimés à différentes températures (20, 25 et 30°C) et concentrations de nourriture (6,12 et 25 Artemia ind~' jour"' ). Les résultats indiquent que le taux de croissance a généralement été augmenté à 12 et 25 Artemia ind~' jour ~' par rapport à 6 Artemia ind~' jour"'. De plus, les taux de croissance les plus élevés de 0,32 ± 0,02 (%RCD/jour) et 0,35 ± 0,01 ont été observes à 30°C quand les balanes ont été nourries respectivement avec 12 et 25 Artemia ind~' jour ~'. Les résultats d'une analyse de variance à deux facteurs ont indiqué que la température et la concentration de nourriture ont un effet positif combiné sur la croissance (F = 3,1, P = 0,02) et le rythme de mue {F = 3,9, P = 0,01) de l'espèce. La concentration de nourriture en particulier a eu un effet majeur sur la croissance et la mue, tandis que les effets de la température ont été mineurs et limités à une augmentation du taux d'alimentation, ce qui pourrait être le résultat d'une augmentation des activités vitales incluant le battement ciliaire. D...

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As the reproductive cycle of barnacles is regulated by different physical and biological factors, their annual breeding patterns can be locally adapted. This study aims to describe the breeding patterns of Microeuraphia permitini in the Persian Gulf, Iran, in three different habitats. Barnacles from three locations were examined monthly during one year. The results showed that M. permitini matures very rapidly in the Persian Gulf. This species reproduces year-round with peak breeding between May and August, and shows a decline in breeding between November and January. Although the Persian Gulf is restricted by the Hormuz Strait, the reproductive activity of the barnacle shows a decline coinciding with the Indian Ocean summer monsoon, as the brood percentage falls in that period. Additionally, comparison of mean breeding activity between the three sites revealed that breeding activity is different in the different habitats surveyed (mangrove swamp > exposed rocky jetty > sheltered rocky jetty).