Lamourouxia dispar Ernst. Smithsonian Contr. Bot.

Francisco-Gutiérrez, Antonio, Ruiz-Sanchez, Eduardo, González, Dolores & Lira-Noriega, Andrés, 2023, Lamourouxia (Orobanchaceae) of Mexico, Phytotaxa 582 (1), pp. 1921-1935 : 1921-1935

6. Lamourouxia dispar Ernst. Smithsonian Contr. Bot. 6: 35–36. 1972. Type:— MEXICO. Guerrero: near Omiltemi, 20 miles west of Chilpancingo , 7500–8000 ft, 31 July1957, R.M.Straw & D.P.Gregory 1062 (Holotype: MEXU00124541 !; isotypes: GH00078570!, MICH1108005!)

Figure 6 F–H .

Sub-shrubs up to ca. 100 cm tall, stems branched along the plant, reclining, woody, glabrescent, non-glandular. Leaves petiolate, petioles up to 1 mm long, narrowly elliptic to lanceolate, 20–28 × 3–8 mm margin serrate, 5–15 teeth each side, teeth ca. 0.5 mm long; apex attenuate, base truncate; membranous, glabrous to minutely glabrescent, nonglandular. Inflorescence a raceme, erect, pedicels thin, 5–7 mm long. Two types of bracts along inflorescence. Upper bracts lanceolate, margin entire, 2–4 mm long. Lower bracts linear 4–13 mm long, margin serrate, 5–8 teeth per side, apex acute, base attenuate. Calyx campanulate without dots on the surface, 8–11 × 5–7 mm, lobes triangular, 5–7 × 3 mm, margin minutely serrate, apex acute, pubescent, non-glandular. Corolla tubular, 40–55 × 9–10 mm, upper lip 10– 14 × 5 mm, lower lip 5–7 × 3 mm, lobes 3 × 2 mm; brilliant red, shortly pubescent, non-glandular. Stamens exserted 2, filaments not seen, anthers 3 mm long. Style not seen, stigma capitate. Capsule ca. 10 mm, elliptic, glabrous. Seeds not seen.

Etymology: —The epithet dispar means dissimilar or different. Ernst (1972) refers to this species as “enigmatic”, due to the similitude of structures present in other species and the combination of features of the section Hemispadon (staminal arrangement) and Lamourouxia (corolla shape and width).

Distribution and Ecology: —The species is endemic to Mexico and is distributed in the states of Guerrero and Morelos. However, two specimens from Oaxaca were reported in the database iNaturalist (www.naturalista.mx/ observations/15750339, www.naturalista.mx/observations/29060643), which are included in the distribution map ( Fig. 6H ). It inhabits cloud forests, pine forests, and pine-oak forests at elevations of 2280–2800 m.

Phenology: —Flowering season from July to November. The peak of collections (two specimens) is September. Immature fruits were photographed in August ( Fig. 6G ).

Examined specimens: — MEXICO. Guerrero: Atoyac de Álvarez, 1–3 km northwest of Puerto El Gallo , 2500– 2750 m, 11 November 1973, Breedlove 36031 ( MO!) . Morelos: Huitzilac, Laguna Tonatihua , 2800 m, 04 September 1988, Castañeda-Robles 1326 ( MEXU!) ; Lagunas de Zempoala , September 1932, Lyonnet 2963 ( MEXU!) .

Figures

FIGURE 6. Lamourouxia dasyantha. A) Frontal view of a flower. B) Inflorescence. C) Leaves. D) Immature fruits. E) Distribution map. Lamourouxia dispar. F) Inflorescence in the field. G) Leaves in the field. H) Distribution map. Credits in Appendix I.