Specimens of this species possess a large white peripheral flange composed of a mass of calcareous spicules similar to that illustrated in the original description of Carterina spiculotesta (Carter, 1877). Tests are trochospiral throughout with chambers increasing rapidly in size. The last whorl comprises only 2-3 chambers. The deep umbilicus may be filled up with a spicular mass that may extend into the peripheral flange. Only the first (about 10) chambers are brownish in color, the other ones are yellowish or white. The spicules are elongated, fusiform, arranged somewhat parallel to the periphery on the spiral side and radial on the umbilical side.
Laevipeneroplis bradyi have planispiral tests with chambers that are partially evolute in early stages and later become flaring. Living specimens show a bright green colour due to chlorophycean endosymbionts.
Early chambers are planispiral and involute, later ones are more or less flaring. Hallock and Peebles (1993) state that this species is morphologically very variable. Chlorophyte symbionts lead to a green colour in living specimens.
Discoidal test, early chambers are peneroplid, later chambers become annular and divided into chamberlets that are connected by a stolon system. Apertures occur along the peripheral margin, they are more or less circular and surrounded by a calcified rim. Living specimens have a brownish colour due to Symbiodinium endosymbionts.
In this species, the first stage is a small, high, conical trochospire consisting of about 2 whorls, flattening out toward the periphery, with a subcircular outline. It is shallow-concave on the umbilical side, with a deep axial depression. The following chambers that make up the flattened second ontogenetic stage are crescent with secondary septa. They become increasingly elongated and are added irregularly, resulting in an unevenly lobed outline of the test. There is no peripheral flange. The spirally elongate-crescent chambers appear as symmetric, petal-shaped, on the umbilical side. The walls are made up of typically “rounded-rectangular” truncated spicules that are scattered. The first chambers are dark brown to blackish while the remaining ones are yellowish or white.
The wall is made up of typically “rounded-rectangular” truncated spicules arranged irregularly. The test begins with a very low-convex trochospiral stage of about 10 chambers, arranged in 2 coils, with oblique sutures. In this stage chambers increase slowly in size. Chambers of the second stage become rapidly elongate-crescent. They are added irregularly and the last ones may have lengths of about one third of the circumference of the chambered test. They are subdivided by secondary septa. The last stage is represented by an irregularly contoured flange, containing randomly dispersed spicules embedded within fine agglutinated particles. The first stage and part of the second stage of the test are dark brown in color. The end of the second stage and the flange are yellowish or white.