thumb|300px|Conceptacle of Fucus thumb|300px|Cystocarp of Amphiplexia hymenocladioides Conceptacles are specialized cavities of marine and freshwater algae that contain the reproductive organs. They are situated in the receptacle and open by a small ostiole. Conceptacles are present in Corallinaceae, and Hildenbrandiales, as well as the brown Fucales. In the Fucales there is no haploid phase in the reproductive cycle and therefore no alternation of generations. The thallus is a sporophyte. The diploid plants produce male (antheridia) and female (oogonia) gametangia by meiosis. The gametes are
thumb|300px|Conceptacle of Fucus thumb|300px|Cystocarp of Amphiplexia hymenocladioides Conceptacles are specialized cavities of marine and freshwater algae that contain the reproductive organs. They are situated in the receptacle and open by a small ostiole. Conceptacles are present in Corallinaceae, and Hildenbrandiales, as well as the brown Fucales. In the Fucales there is no haploid phase in the reproductive cycle and therefore no alternation of generations. The thallus is a sporophyte. The diploid plants produce male (antheridia) and female (oogonia) gametangia by meiosis. The gametes are released into the surrounding water; after fusion, the zygote settles and begins growth.
Two taxa, the corallines and Hildenbrandiaceae, bear conceptacles, although the striking difference between their formation indicates that the conceptacles are not homologous. Similar structures also exist: cryptostomata are similar to conceptacles but differ having only hairs and are sterile; caecostomata, are found only in Fucus distichus, in these the ostiole becomes blocked during development.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).