TY - JOUR

T1 - When similar beginnings lead to different ends: Constraints and diversity i cirripede larval development

AU - Høeg, Jens Thorvald

AU - Møller, Ole Sten

N1 - Key words: Cyprid, evolution, larval development, life cycle, metamorphosis, nauplius, parasitology, settlement, reproduction

PY - 2006

Y1 - 2006

N2 - Cirripedes are fascinating models for studying both functional constraints and diversity in larvaldevelopment. Adult cirripedes display an amazing variation in morphology from sessile suspensionfeeders that still retain many crustacean characters to parasites that have lost virtually all arthropodtraits. In contrast, cirripede larval development follows a common scheme with pelagic larvaecomprising a series of nauplii followed by a cyprid. Variations are mostly concerned with whetheror not the nauplii are feeding and the degree of abbreviation of development, culminating in specieswhere the larvae hatch as cyprids. The cypris larvae are very similar among the ingroups of theCirripedia, but interesting variations occur in structures used for substrate location and attachment.The cyprid is specialized to both swim through the water and actively explore the substratum bywalking on the antennules and using an array of sensory organs in search for a suitable site toattach. This unique morphology and behavior of the cyprid have enabled the Cirripedia to colonizewidely different habitats ranging from hard rock to soft animal tissue. Yet, the cyprid canmetamorphose into juveniles as different as a setose feeding barnacle and the vermiform stages ofthe parasitic forms. This emphasizes the importance of the cyprid as one of the key features for theevolutionary success of the Cirripedia.

AB - Cirripedes are fascinating models for studying both functional constraints and diversity in larvaldevelopment. Adult cirripedes display an amazing variation in morphology from sessile suspensionfeeders that still retain many crustacean characters to parasites that have lost virtually all arthropodtraits. In contrast, cirripede larval development follows a common scheme with pelagic larvaecomprising a series of nauplii followed by a cyprid. Variations are mostly concerned with whetheror not the nauplii are feeding and the degree of abbreviation of development, culminating in specieswhere the larvae hatch as cyprids. The cypris larvae are very similar among the ingroups of theCirripedia, but interesting variations occur in structures used for substrate location and attachment.The cyprid is specialized to both swim through the water and actively explore the substratum bywalking on the antennules and using an array of sensory organs in search for a suitable site toattach. This unique morphology and behavior of the cyprid have enabled the Cirripedia to colonizewidely different habitats ranging from hard rock to soft animal tissue. Yet, the cyprid canmetamorphose into juveniles as different as a setose feeding barnacle and the vermiform stages ofthe parasitic forms. This emphasizes the importance of the cyprid as one of the key features for theevolutionary success of the Cirripedia.

M3 - Journal article

VL - 49

SP - 125

EP - 142

JO - Invertebrate Reproduction and Development

JF - Invertebrate Reproduction and Development

SN - 0792-4259

IS - 3

ER -