Life habit: lichenized; Thallus: little or none, crustose, areolate, without elongated lobes; prothallus: absent; surface: orange or gray, smooth, without asexual propagules; Apothecia: adnate, 0.3-0.7 mm, lecanorine; disc: orange, flat, epruinose; margin: persistent, flush; thalline margin present, concolorous with thallus; proper margin visible, little lighter than disc; parathecium: elongate to oval cells; exciple below hypothecium amorphous or cellular (paraplectenchymatous); epihymenium: golden, K+ red, C-; hymenium: hyaline 60-85 µm tall; paraphyses: 1-2 tip cells slightly swollen or swollen, not branched or with few branches; subhymenium hyaline; asci: cylindrical, 8-spored; ascospores: hyaline, 2 locules, ellipsoid, 10-14 x 5.5-7 µm, isthmus 1.5-4(-5.5) µm, spore end wall thin; Pycnidia: present, mostly immersed, ostiole orange; Spot tests: apothecial margin K+ red, C-; thallus K- or K+ red; Secondary metabolites: parietin, fallacinal, emodin, and teloschistin.; Substrate and ecology: on wood or bark; World distribution: worldwide; Sonoran distribution: southern California, Arizona, Baja California and Baja California Sur.; Notes: This treatment of the Caloplaca holocarpa group is very tentative. As treated here this species is restricted to bark and wood and usually has some orange margin on the lower parts of the apothecia and orange places on the gray thallus that may be apothecial initials. The thallus is often scant and some collections have a little thalline margin at the base of the apothecia. The apothecia are usually small and the margins are about the color of the discs. Caloplaca stanfordensis is probably in this group but that has no orange color in the thallus. Hoffman in the original description described the thallus as "aurantia" while Acharius in his description of pyracea described the thallus as "cinereascente". Only examination of the types will determine whether they are synonyms. The species on calcareous rocks under C. holocarpa all seem to be C. crenulatella while the material on non-calcareous rocks are another species. 

Canada

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: NNR - Unranked

Rounded Global Status Rank: G5 - Secure

Reasons: Caloplaca holocarpa is a common lichen species that grows on the bark of woody plants, old wood, and sometimes on rocks. This species is temperate to arctic-boreal in western North America and ranges south to California and Arizona. It also occurs commonly throughout the midwest and eastern United States (Thomson 1997).

Comments: Stable. See Vitt, Marsh and Bovey, 1988. Mosses, Lichens & Fernsof Northwest North America.