Shell elongate-fusiform, length 6.5-7.9 mm, length: width ratio < 3 (range 2.5-2.9), aperture length more than half shell length (range 52-58%). Protoconch 0.37-0.40 mm wide at base; complete protoconch not seen. Teleoconch 5.1-5.7 whorls, spire somewhat convex, shouldered at sutures. First postnuclear whorl with 12-17 axial ribs and 2-3 spiral cords; spiral cords increase to 4-7 on penultimate whorl and 21-29 on body whorl, subsutural cord usually strongest. Axial ribs increase to 25-42 on penultimate whorl and 29-45 on body whorl, sometimes almost fused on body whorl at higher counts. Intersections of cords and ribs raised as pustules about as wide as cords, wider than ribs; pustules weaker with high rib count. Near and above periphery intercordal spaces often groove-like, being narrower than adjacent cords; intercordal spaces wider anteriorly, particularly at level of columellar folds. Microsculpture of uniform axial riblets (average spacing 4 mu crossing axial ribs and spiral cords and their interspaces and intersections. Aperture narrow, with slight posterior depression reminiscent of turrid notch, outer lip smooth or slightly undulate outside, with 10-12 denticles inside, denticles becoming obsolete toward siphonal canal. Columellar folds 4-5, interior of aperture without lirations. Siphonal canal open, slightly recurved, siphonal notch shallow.
Ground color of shell pinkish orange, or light-red, with scattered white pustules singly or in small clusters at periphery of whorls and sometimes also medially on body whorl.

We are uncertain whether material from the Sahul Bank is conspecific with Thala evelynae. It differs in being smaller (<5 mm vs. >6 mm), in having fewer aperture denticles (8-9 vs. 10-12), fewer ribs on the penultimate whorl (19-23 vs. 25-42) and having a narrower protoconch (0.35 vs. 0.37-0.40 mm), but all of these features could be correlated with size. More material must be examined to determine if they intergrade or are distinct species.
Thala evelynae differs from T. mirifica in having a broader shell (length to width ratio < 3 vs. > 3), a more strongly convex spire, a wider aperture, and weaker pustules. It differs from T manolae Turner, Gori & Salisbury, 2007 in the same ways, except that length to width ratio is similar; also it has fewer apertural denticles (10-12 vs. 13-15) than T. manolae, with the denticles becoming obsolete anteriorly.

Type locality: Balicasag Island, Bohol, Philippines. Known only from the Visayan region of the Philippines.