oblique; aperture subcircular, flattened at paries; columella with a single simple tooth at its base; interior of outer lip thickened, bearing approx.
oblique and nearly tangential, aperture subcircular; columella shallowly concave with a rounded tooth at its base; interior of outer lip of mature individuals subterminally thickened and set with approx.
5 mm), thin and fragile, lenticular to globose, olive-green to brown, frequently with irregular darker axial bands, but lacking spiral colour pattern; apical surface sculptured with close-set axial riblets, usually lustreless, base smoother and more glossy; peristome
interrupted in parietal region; outer lip thin with membranous periostracal fringe, sometimes slightly thickened basally; umbilicus open, width variable; protoconch of [+ or -] 1.
Diagnosis: Shell of moderate size (adult diameter up to 31 mm), lenticular to globose, more or less uniformly yellowish or greenish brown, or brown, lacking spiral colour pattern; apical surface sculptured with close-set axial riblets, base smoother and more glossy; outer lip slightly thickened and without periostracal fringe; peristome
interrupted in parietal region; umbilicus open, width narrow to moderate; protoconch of approx.
Diagnosis: Shell of moderate size (adult diameter up to 34 mm), discoidal to globoselenticular, usually with distinct spiral colour pattern; sculptured by anastomosing axial riblets producing a somewhat pitted or wrinkled sculpture; outer lip slightly thickened and without periostracal fringe; peristome
interrupted in parietal region; umbilicus open, width moderate; protoconch of 1.
The spines of the urchins were removed by a slim pointed tip Lodestar stainless steel tweezers, L605014 (Limited Exempt Private Company, Singapore); the peristome
was cut using a scalpel; the Aristotle's lantern was removed using forceps, and finally the coelomic fluid was removed.
double, exostome cross-striolate below, papillose above; endostome segments papillose, membrane basal high, cilia none.
Entries on individual genera include identifying features, the apical system, ambulacra, interambulacra, peristome
, spines, color, and distribution.
The aim of the paper is to: (1) systematically describe a new species of cornulitids from the Wenlock of Gotland, (2) discuss the function of the unique undulating edge of the peristome
in Conchicolites crispisulcans sp.
Endoperodial body sessile 2 cm across globose to subglobose or slightly depressed onion shaped when not depressed smooth seated in saccate slightly depressed basel area of exoperidium grayish brown with occasional darker tints; Peristome
fibrillose and conical dark brown surrounded by circular shallow groove.
Biofilms enhance the bacterial proportions in a way that the aggregates may be larger than the Euplotes peristome
Qualitative characters used in species description include: colour of the soft parts (reddish or pale) based on field notes and/or from the colour of dried-in soft parts visible through the shell, protoconch shape, protoconch sculpture, teleoconch sculpture (other than rib distance), umbilical development, peristome
development, overall shell shape, whorl convexity, as well as the arrangement of barriers in the aperture and deeper within the body whorl (see below).