Protologue Description: Leptodictyum wallacei B. H. Allen & Magill, sp. nov. TYPE: U.S.A. Texas: San Saba Co., Hext Spring. 4 mi. W of Cherokee. off Ranch Road 501 USGS Magill Mountain quad map, 30°58'49”N, 098°46'22"W, 1555 ft. elev., 13 Dec. 2003 Brad Wallace s.n. (holotype, MO; isotypes, BM, DUKE, FH, H, MICH, NY, PC, S, US). Figure 1.

Species haec a Leptodictyo ripario plantis rigidis, marginibus foliorum serrulatis, costis latioribus, foliis valde tortilibus ubi siccis pilisque axillaribus rubris differt.

Plants slender in green to yellow-green. dense masses of long, stiff, sparingly branched strands. stems stiff, irregularly branched, in cross section with sclerodermis of 4 to 5 rows of small. yellow or reddish, thick-walled cells, cortical cells enlarged, yellowish to hyaline, firm-walled, small central stand present: paraphyllia absent; pseudoparaphyllia foliose: rhizoids not seen: axillary hairs 3- to 5 celled, lower 1 to 2 cells irregularly quadrate, upper cells rectangular to cylindrical, all cells red. Leaves erect-spreading and individually strongly twisted when dry, erect when wet, evenly spaced, 2.0-2.5 mm long, lanceolate, smooth, long-acuminate to a broad, blunt tip, concave, not decurrent; margins plane to erect, obscurely serrulate to subentire; costae single, broad, to 70 µm wide at base, extending; ÿ the leaf length, in cross section cells ± homogeneous, thick-walled; laminal cells linear-rhomboidal to vermicular, firm-walled, upper cells to 70 X 6 µm, median leaf cells to 120 X 6 µm, cells near leaf insertions long-rectangular, firm-walled, at margins cell often subquadrate, alar cells not differentiated. Perichaetial and perigonia not seen. Sporophytes not seen.
Name derivation: Named after Brad Wallace