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Kalops monophrys is known by over 125 specimens from the Bear Gulch Limestone. K. monophrys is distinguished from its smaller sister species, Kalops diophrys, by having more caudal fin rays, a different number of supraorbital bone rows, and the development of its ganoine ridging at a larger size. The cranial osteology of Kalops most closely resembles that of the poorly known Palaeoniscus and "Elonichthys" serratus. The snout structure is closest to that of the Tarrasiiformes. Diagnosis from Poplin & Lund 2002, p. 1014: "Total length ranging from 44 to 116 mm; postrostral meeting the frontal in the midline anteriorly to mid-orbit level; ovoid antorbital; one row of supraorbitals; about five infraorbitals and five suborbitals; anterior extremity of the preopercle as high as the posterior plate of the maxillary; about 15 branchiostegal rays; one pair of extrascapulars; supracleithrum higher than opercle; from eight up to 17 predorsal median scutes, continuous between skull and dorsal fin; dorsal fin spanning 14 scale rows; anal fin with fulcra; scaled lobe of the caudal fin at 25 degrees to the body axis." Line drawing from Poplin & Lund 2002, p. 1017: Identified by oilshale using Poplin & Lung 2002. References: Poplin, C., & R. Lund (2002) "Two Carboniferous fine-eyed paleoniscoids (Pisces, Actinopterygii) from Bear Gulch (USA)." Journal of Paleontology 76: 1014-1028.

Taxonomy from Fossilworks.org. Kalops diophrys is distinguished from its larger sister species, Kalops monophrys, by fewer caudal fin rays, a different number of supraorbital bone rows, and the development of its ganoine ridging at a smaller size. The cranial osteology most closely resembles that of the poorly known Palaeoniscus and "Elonichthys" serratus. The snout structure is closest to the Tarrasiiformes. Diagnosis from Poplin & Lund 2002, p. 1020: "Total length ranging from 50 to 96 mm; in the midline, postrostral meeting the frontal at mid-orbitalevel; two rows of supraorbitals; presence of a bone, probable spiracula lateral to the dermosphenotic; dermopterotic with a spur posterolateral to the anterior extrascapular row; six infraorbitals, and about 12 suborbital bones; anterior limb of the preopercle not as high as the maxillary posterior plate; presence of a small postspiracular behind the dermohyal; opercle tall, two and a half as high as long; ten to 12 branchiostegal rays; two rows of extrascapulars: anterior one with five paired and one median ossicles, posterior one with one paired bone carrying the supratemporal commissure; supracleithrum not as high as the opercle; scales of the lateral line hexagonal; three to six predorsal scutes, not reaching the skull; pectoral fin fan shaped; dorsal fin long based, spanning about 21 scale rows; anal fin without fulcra; scaled lobe of the caudal fin at 30 degrees to the body axis." Line drawing from Poplin & Lund 2002, p. 1022: Identified by oilshale using Poplin & Lund 2002. References: Poplin, C., & R. Lund. 2002. "Two Carboniferous fine-eyed paleoniscoids (Pisces, Actinopterygii) from Bear Gulch (USA)." Journal of Paleontology 76: 1014-1028.