Callyspongia crassa

The name crassa derives from the Latin word crassus meaning solid, thick, fat, or dense.[8] Its common name, the prickly tube-sponge, comes from its physical appearance as it is a tube sponge and it is nearly completely covered in spines.[9] It was previously named Sclerochalina crassa, but was eventually moved to the genus Callyspongia.[2][10]

The genus Callyspongia belongs to the family Callyspongiidae. This family contains four genera: Arenosclera, Callyspongia, Dactylia, and Siphonochalina with Callyspongia being the largest and containing over 180 species.[11] They are under the phylum Porifera, making them a sponge. Specifically, they are Demosponges, which is the most diverse class in the phylum Porifera.[12]

The prickly tube-sponge is a large, flexible, brown, sometimes red, tube that can be found as a singular tube or as a cluster. It has been known to reach up to 50 centimeters (~20 inches) with specimens as small as 2 mm having been found, but it typically has an average diameter of 30 centimeters (~12 inches). Most of its surface is covered with spines or spine-like protrusions which tend to taper away towards the upper part of the tube.[2][4][9]

The main use of these sponges is for marine drugs.[4] Many species of sponge are used for marine drugs due to their bioactive components, many of which are used for antiseptic agents.[4][9] Callyspongia crassa has over 20 compounds that attribute to its medical content. Such compounds contain many biological properties such as anti-oxidant, decrease blood cholesterol, anti-inflammatory, anti-fungal, anti-microbial, cancer-preventive, hypercholesterolemia, nematicide, anti-cancer, anti-tumor, pesticide, lubricant, anti-androgenic, flavor, anti-bacterial, anti-tumor cytotoxic effects, anti-arthritic, anti-asthma, diuretic, and anti-diabetic abilities.[9]

Sea sponges are also of important use in the wild. They play an important role in nutrient recycling and in filtering the water[5] which is useful for many of the reefs that they live in as clearer water makes sunlight more accessible for photosynthesizing organisms in the same area.[13] Many sponges also serve as a habitat for a variety of other organisms. They can serve as microhabitats,[5] with conditions different from the larger surrounding area. Tube sponges specifically, often have small fish and other inhabitants living inside of the tubes.[6]