Organic coatings and ontogenetic particle selection in Streblospio benedicti Webster (Spionidae: Polychaeta)

摘要: Abstract Surface deposit feeders select food particles based upon characteristics including size, texture, specific gravity, and organic coatings. Spionid polychaetes feed at the sediment–water interface using a pair of ciliated palps switch between surface feeding suspension primarily as function water flow. Juveniles adults some spionid species have different stable isotopic carbon signals, indicating ingestion sources potentially ability to differentiate cues ontogenetically. In present study, responses juvenile adult Streblospio benedicti Webster seven coatings bound glass microbeads were tested five amino acids two carbohydrates. Coated versus uncoated presented in equal proportions area. highly selective for all types organically coated beads—87.1% beads ingested beads. For coatings, there ontogenetic differences; juveniles more threonine proline. These differences may result diet shifts that allow maximization energy and/or essential nutrients during critical early life-history stages. Particle selection tentaculate is generally thought occur particle contact transport mouth, typically characterized passive process. Active site everted pharynx was observed quantified S. benedicti. Organically represented 50% ambient experimental treatment, 64.4% transported along palp after contact, 81.8% pharyngeal rejection behavior. Of reaching pharynx, 26.9% rejected by ciliary sorting on before ingestion, uncoated. Our study demonstrates microphagous handle bulk are capable significant levels active particles.