Phylum Porifera PDF - Fall 2024

Phylum Porifera BZ 212 Animal Biology – Invertebrates Fall 2024 Zach Grochau-Wright, PhD Every Phylum focused chapter in your textbook has a table like this in its first few pages. Make sure you understand its contents well for each Phylum we cover. Sponge Structure Aquiferous system powered...

Phylum Porifera BZ 212 Animal Biology – Invertebrates Fall 2024 Zach Grochau-Wright, PhD Every Phylum focused chapter in your textbook has a table like this in its first few pages. Make sure you understand its contents well for each Phylum we cover. Sponge Structure Aquiferous system powered by choanocytes supports feeding, gas exchange, and waste expulsion. Pinacoderm made up of pinacocytes form the outer surface of sponge. Mesohyl layer between dermal layers. May contain spicules, amebocytes, and other cell types. Choanoderm layer of choanocytes creates water current through sponge. Sponge Body Forms Spicule skeletal Spongin network structure Skeletal Support Sponges may be supported by spicules and/or collagen including a unique form of collagen called “spongin” Spicules may be siliceous or calcium carbonate. Skeletal make-up up and shape is important for classifying sponges. Spicule Diversity Cell type flexibility in sponges Sogabe et al. 2019 Nature  https://youtu.be/ORV3qV8GFF4?si=SzAng9QODaGLbS5k Sponge regeneration https://youtu.be/swKwTNn8Oz4?si=Vxy3GpzB6QFhrD3c Most sponges filter feed But some sponges are predatory too! Some even live in trees! Drulia (?) sponge. Sponges play important role in cycling organic matter to higher trophic levels , Rix et al. 2016 Scientific reports, De Goeij et al. 2013 Science  Sponge defenses Sponges have mechanical defenses (i.e. spicules) and chemical defenses. Many medicines have been discovered in sponges! Drugs discovered from T. crypta for treating COVID-19, HIV, and Cancer Tectitethya crypta, a Caribbean Sea Sponge Sponge reproduction Can reproduce asexually through fragmentation. Reproduce sexually – Release sperm and egg into water, external fertilization, oviparity. – Sperm released, swim to another sponge, internal fertilization, viviparity. – Extreme diversity in sexual differentiation: sequential hermaphroditism, gonochoristic, switch sexes regularly. Sperm release Egg release  Hexactinellida Diversity of Developmental Calcarea Homoscleromorpha and Larval forms Homology to other animals not clear, need more research! Some controversy over if “true gastrulation” occurs during sponge development. Demospongiae Phylogeny of Sponges Hexactinellida Demospongiae Homoscleromorpha Calcarea No spongin True spongin skeletons Calcium Syncytial skeletons Spicule carbonate epithelial cells skeleton spicules Fused vase- reduced or like skeletons absent Six-rayed spicules Trait evolution is a little oversimplified here, see textbook for more detail Class Hexactinellida Euplectella aspergillum Spicules composed of silica and six rayed Spicules often fused into an intricate lattice; cup or vase shaped Syncytial epithelia; sycon or leucon body form Often found at 450 to 900 m depths in tropical West Indies and eastern Pacific. Glass sponges. Trichimella larvae Glass Sponge- Shrimp Symbiosis https://youtu.be/bI6QxENCcTc?si=pM hIw_zo_2ZY5r1A Monachora arbuscula Class Demospongiae Spongia officinalis (Bath sponge) >80% of extant sponges Brilliantly colored sponges with needle- shaped or four-rayed siliceous spicules or spongin or both. Most with leucon body form; may be up Spongilla lacustris to 1 m in height and diameter. (Freshwater) Includes one family of freshwater sponges, Spongillidae, and the bath sponges. Cliona, Spongilla.  Oscarella lobularis Class Homoscleromorpha Anatomically simple and encrusting in form. Leuconoid body form. Siliceous spicules small and simple in shape or absent. Occur at depths ranging from shallow marine shelves to depths of 1,000 m. Oscarella, Plakina. Cinctoblastula larvae Plakortis spp.  Class Calcarea Spicules composed of calcium Clathrina clathrus carbonate. Spicules are needle shaped or have three or four rays. Ascon, leucon, or sycon body forms; all marine. Calcareous sponges. Grantia (=Scypha), Leucosolenia. Leucetta primigenia