Freshwater sponges (Porifera: Spongillidae) from Lake Llopango, El Salvador, with observations on spicule
malformation in Spongilla alba.
Length of author's specimen spicule
is larger than others.
The chromosphere is characterized by numerous structural features, the most important of which are spicules
Inspired by the sponges' lightweight but impenetrable defense system, experts from Johannes Gutenberg Universitat (including Muller) and the Max Planck Institute for Polymer Research built a synthetic version of the creatures' spicules
(tiny, prickly splinters) using calcite and silicatein-[alpha], a protein from siliceous sponges that catalyzes the formation of silicon dioxide (silica)--the main ingredient in Porifera spicules
They can appear as a variety of shapes often described by observers as mounds, trees or hedgerows, and can form arches, loops, spires or spicules
Laboratory preparation of sponge spicules
(megascleres, microscleres, and gemmoscleres) was performed using an acid digestion, followed by washings in water and ethyl alcohol.
Coeval transgressive sedimentological changes occur in the upper part of the Gipshuken Formation (West Spitsbergen), where brachiopods, bryozoans, and sponge spicules
give evidence of the more open marine influx (Keilen 1992).
4, the chromosphere is filled with spicules
 which seem to extend as disoriented hair beyond the surface of the Sun.
Thick-bedded Limestone with yellow weathered to buff color and in some cases pink to red having radiolaria, saccocoma, tintinid and sponge spicule
rufescens to have oligosaccharides, an important feature associated with calcium carbonate in sea urchin spicule
matrix proteins (Cho et al.
In the category of "killer sponge" is a carnivorous deep-sea sponge - Chondrocladia (Meliiderma) turbiformis - that displays a special type of spicule
for which the new term "trochirhabd" has been coined.
Genital cone well developed with only one simple and grooved spicule
However, using caudal papillae patterns, spicule
lengths and other morphological differences, Bursey et al.
Intraperitoneal rupture typically results from shearing of the distended bladder by a lap belt, whereas extraperitoneal rupture often results from laceration by a bony spicule
from a pelvic fracture.
Each endosomal spicule
in these three species is clearly twisted around the long axis (cf.