Hyptis pseudolantana Epling (1941: 555)

González-Gallegos, Jesús Guadalupe, Castro-Castro, Arturo, Argüelles, Alejandra Flores- & Romero-Guzmán, Ariosto Rafael, 2014, Discovery of Hyptis pseudolantana in Jalisco and Michoacán, and description of H. cualensis and H. macvaughii (Ocimeae, Lamiaceae), two new species from western Mexico, Phytotaxa 163 (3), pp. 149-165 : 150-158

Hyptis pseudolantana Epling (1941: 555) ( Figs. 1 and 2A–D )

Type:— MEXICO. Guerrero. Coyuca de Catalán : Aguazarca–Filo, District Mina, Guerrero, 9 November 1937 (fl, fr), G. B. Hinton et al. 11266 (holotype UC, isotypes K!, MO!, US-00121889!, US-01014362!) .

Perennial herb to subshrub, erect, 0.6–2(–2.5) m tall, arising from a small xylopodium, aromatic. Stems glabrous to puberulent and pilose, with the hairs concentrated towards young branches. Leaves with petioles (1–) 6–20 mm long, pilose; blade ovate to ovate-elliptic, 1.5–7.1 × 0.9–4.1 cm, acute to acuminate at the apex, rounded to shortly cuneate at the base, serrate margin, pilose in both surfaces. Inflorescences axillary or terminal, spiciform, 4–18 cm long, with pectinate opposite cymes at each node, 6–18 flowers per cyme, peduncles 3–8.7 mm long (sometimes hidden by the flowers); peduncle bracts conformed by reduced leaves 2.1–4.9 × (0.8–) 1.5–2.2 mm, bracteoles linear, 1.4–2.8 mm long; inflorescence axes, peduncles and bracteoles sparsely pilose and glandular-punctate. Flowers sessile or with pedicels less than 0.5 mm long. Calyx tube (1.7–)2.2–3.5(–5) mm long, and 1.6–1.8 mm wide at the throat in flower (up to 4.4 × 2.2 mm in fruit), sparsely pilose and covered with some short glandularcapitate hairs and or sessile glandular dots, puberulent, internally with a ring of hairs attached 1–2 mm below the line of the teeth or at the middle of calyx tube length; teeth triangular and attenuate towards the apex, 9– 1.5 mm long and straight in flower (up to 2 mm in fruit and backwardly oriented). Corolla pale violet, dull lavender to white, sparsely pilose towards the lobes; tube (5.1–) 6.5–7.3 mm long, (1.5–) 2.3–2.8 mm wide at the throat, lobes subequal, 1.7–3 mm long. Stamens 4, attached at 5.3–5.5 mm of corolla tube length, the posterior stamens attached a little below than the anterior ones; filament (1.2–)1.5–1.6(–2.4) mm long, pilose; theca 0.2–0.4 mm long. Style (3.3–) 4.4–6.3 mm long, white and glabrous, without stylopodium; stigma bifurcate, the branches rounded at the apex. Mericarp 4, ovoid to turbinate, 1–1.3 × 0.6–0.8 mm, slightly trigonous, light or dark brown, smooth to muriculate, nitid, pulverulent, glabrous, with a markedly suture line in the external face.

Distribution, habitat and phenology:— Hyptis pseudolantana inhabits the western portion of the Sierra del Halo, in the municipality of Tecalitlán, Jalisco, the eastern side of Sierra de Coalcomán, Michoacán, and northeastern slopes of Sierra Madre del Sur in the municipality of Coyuca de Catalán, Guerrero (figure 1). It grows in pine-oak and oak forests and in ecotones with montane cloud and tropical deciduous forests, at elevations from (1400–) 1650–2200 m. It shares habitat with Carpinus caroliniana Walter , Cosmos carvifolius Benth. , Cunila pycnantha B.L.Rob. & Greenm. , Dendropanax arboreus (L.) Decne & Planch., Fuchsia arborescens Sims , Galphimia glauca Cav. , Inga micheliana Harms , Jungia pringlei Greenm , Pinus douglasiana Martínez , P. hartwegii Lindl. , Quercus scytophylla Liebm. It flowers and fructifies from August to May.

Taxonomic relationships:— Hyptis pseudolantana was assigned by Epling (1941) to section Rhytidea Epling

(1933b: 80) due to the internal ring of hairs of the calyx placed at the middle of its length. However, this species is

more similar to those from section Mesosphaeria Bentham (1833 b: 122) subsection Pectinaria Epling (1933b: 97) , than to Hyptis rhytidea Bentham (1839: 21) , the other member of section Rhytidea Epling (1933b: 80) . It shares with subsection Pectinaria the habit (herbs to subshrubs or rarely trees), petiolate leaves, ovate and rarely lanceolate, pectinate or globose cymes with peduncles longer than the calyces and, linear floral bracts. It differs from the species of section Rhytidea due to its membranaceous leaves (vs. coriaceous), cymes clearly pedunculated (vs. subsessile), and linear floral bracts (vs. ovate). As stated in the introduction, the classification of the genus is still unstable, so we have no elements to unequivocally support the inclusion of H. pseudolantana to one of the infrageneric groups.

Hyptis pseudolantana is similar to H. pectinata ( Linnaeus 1759: 1096) Poitier (1806: 474) and H. urticoides Kunth (1817: 320) from subsection Pectinaria , but it can be easily distinguished from these because the calyx is infundibuliform instead of tubular, with triangular teeth rather than linear, and calyx tube without an internal welldefined ring of hairs projecting between calyx teeth. It is also similar to Hyptis pinetorum from subsection Mutabiles Epling (1933b: 102), but it can be differentiated by means of the glandular capitate hairs restricted to the calyces and not spread throughout stems, leaves and inflorescences, usually shorter petioles [(2.5–)6–20 vs. (18–) 30–55 mm], flowers arranged in pectinate cymes instead of spherical cymes, shorter peduncles [3–7 vs. (8–) 12–30 mm], shorter calyx tube (1.7–2.2 vs. 3–4.5 mm), and shorter style [(3.3–)4.4–6.3 vs. 6.2–7.7 mm] (table 1).

Hyptis pseudolantana was formerly known only from the type collection series from Guerrero, but here, several specimens from Jalisco and one from Michoacán are assigned to this species (figure 1). Hyptis pseudolantana is not reported for the latter two states in most recent floristic lists, although the specimen McVaugh 22775 (ENCB) was included as an undetermined Hyptis for Michoacán ( Rodríguez-Jiménez & Espinosa-Garduño 1996, Ramírez-Delgadillo et al. 2010). Our collections and other herbaria material reviewed differ in some characters from the original description of the species. Nonetheless, these differences are not so abrupt and consistent as to demand the need of naming the new discovered populations as a different taxon. The morphological discrepancies are: petioles 1–2 mm long in the original description vs. 6–20 mm long in the new discovered populations, axillary inflorescences vs. most of them terminal, calyces internally ornate with a ring of hairs attached at the middle of its length vs. attached 1–2 mm below calyx teeth line, and white corollas vs. pale violet to dull lavender. It is likely that the relatively low number of specimens that were surveyed to elaborate the original description by Epling (1941) promoted these discrepancies. Moreover, the distribution of the species is composed of three disjunct populations around Balsas Depression; it can be expected that more extensive exploration in mountains between these points and with adequate elevations for the species establishment will reveal new populations. This ultimately could help to better understand the morphological variation of H. pseudolantana .

If the classification proposal of Harley & Pastore (2012) is followed, H. pseudolantana would fit better within their definition of the genus Mesosphaerum Browne (1756: 257) .

Conservation assessment:— Hyptis pseudolantana has a wide geographical distribution and their populations consist of numerous individuals, so it appears not to be in danger of extinction.

Additional specimen examined:— MEXICO. Jalisco. Tecalitlán: Sierra del Halo , near a lumber road leaving the Colima highway, 7 miles SSW of Tecalitlán and extending southeasterly toward San Isidro, 1400 m, 13 August 1957 (fl, fr), R . McVaugh 16149 ( MICH!); Sierra del Halo , near a lumber road leaving the Colima highway, 7 miles SSE of Tecalitlán and extending SE toward San Isidro, 2000–2200 m, 28 November 1959 (fl), W . N . Koelz 1171 & R . McVaugh ( MICH!); 46 km carr. Ciudad Guzmán-Pihuamo, por la brecha Llanitos-Canutillo , a 16 km, 1650 m, 14 May 1988 (fl, fr), Pichardo 47 ( MEXU!); 14 km al E de Llanitos , brecha a Canutillo , 1750 m, 18 March 1990 (fl, fr), Villa et al. 673 ( IBUG!, IEB!); brecha a Mexicanillo , Sierra del Halo , 2060 m, 13 March 1996 (fl, fr), Ramírez et al. 3599 ( IBUG!); Sierra del Halo , cañada La Jabalina , predio Las Palomas , 3.5 km en línea recta al O de Alotitlán , 19º15’35”N, 103º14’58”W, 1700–1750 m, 23 February 2012 (fl, fr), A . Castro-Castro, E . A . Suarez- Muro & A . Frías-Castro 2619a ( IBUG!); Sierra del Halo, predio Los Fresnos, Puerto de Ortiz , 2.5 km en línea recta al O de Alotitlán, 19º15’3”N, 103º14’8”W, 1700 m, 23 February 2012 (fl, fr), A Castro-Castro, E . A . Suarez- Muro & A . Frías-Castro 2747a ( IBUG!); Sierra del Halo, cerca del río Canutillo en el predio Las Palomas , 19º15’35”N, 103º14’58”W, 1700–1750 m, 8 March 2012 (fl, fr), A . Castro-Castro 2680a, E . A . Suarez-Muro & A . Frías-Castro ( IBUG!); Sierra del Halo, 12 km en línea recta al E de Pihuamo, entre los predios Las Palomas y La Esperanza, 19º15’35”N, 103º14’58”W, 1980 m, 29 March 2012, A . Castro-Castro, E . A . Suarez-Muro & A . Frías- Castro 2842a ( IBUG!) . Michoacán. Aguililla: near the pass ca. 15 km S of Aserradero Dos Aguas ( NW of Aguililla ), 1650–1700 m, 4 March 1965 (fl), R . McVaugh 22775 ( ENCB!, MICH!) .

Hyptis cualensis J.G.Gonzále & Art.Castro sp. nov. ( Figs. 1 , 2E–H and 3 )

H. rhytidea affinis sed bracteis floralibus semper linearibus (vs. foliis reductis constitutus), plus floribus per verticillastum, bracteolis brevioribus, calycum tubo in florem et in fructum brevioribus, trichomatum annulo interno affixo ad 1–2 mm infra dentium lineam, calycum dentibus in florem et in fructum brevioribus et distinctis (vs. calycum dentibus superis ad basem connatis), et nuculis plus minusve brevioribus differt.

Type:— MEXICO. Jalisco. Puerto Vallarta: Ojo de Agua , 20º30’43.5”N 105º12’20.5”W, 1227 m, 1 May 2013 (fl, fr), A . Flores- Argüelles & A . R . Romero-Guzmán 662 (holotype IBUG!, isotypes IEB!, MEXU!) .

Shrub up to 3 m tall, stems puberulent and covered with some sessile amber glandular dots, the hairs more abundant in young branches and toward the apex, very aromatic. Leaves with petioles 5.6–9.6(–11.5) mm long, pilose, puberulent with sessile amber glandular dots; blade lanceolate to narrow lanceolate, 5.7–9.9 × 0.8–2 cm, decreasing in size toward the inflorescences, coriaceous, acute to acuminate at the apex, shortly rounded at the base, margin obscurely serrate, upper surface lustrous, pilose in the main vein, puberulent with sessile amber glandular dots, pilose in the main vein, tomentose beneath and with secondary and tertiary veins conspicuous. Inflorescences terminal, spiciform and dense (6.5–)10.5–21 × 1.4–2.1 cm, with pectinate opposite, subsessile or pedunculate cymes at each node, 7–10 flowerered, peduncles 1.2–4.6 mm long, peduncle bracts compose of reduced leaves at the base of the inflorescence and progressively differentiated into linear structures (2.5–) 4–12 mm long, bracteoles linear, 1.3–2.2 mm long; inflorescence axes, peduncles and floral bracts pilose, puberulent and with some sessile glandular dots. Flowers sessile. Calyx tube 1.6–2.5 mm long, and 1.6–2 mm wide at the throat in flower (up to 3.1–3.5 × 2.5–2.7 mm in fruit), purple, incanous, puberulent and covered with sessile glandular dots, internally ornate with a ring of hairs attached from teeth line to 1–2 mm below; calyx teeth triangular, 0.8–1.3 mm long in flower (up to 1.5 mm in fruit). Corolla pink, externally and internally tomentose; tube 5.6–6.2 mm long, 1.3–2.4 mm wide at the throat, lobes subequal, 1.7–2.1 mm long. Stamens 4, attached at 3.6–4.1 mm of corolla tube length; filament 1.7–2.7 mm long, pilose; thecae 0.5–0.8 mm long. Style 5–7.8 mm long, brown and glabrous, without stylopodium; stigma bifurcate at the apex, the branches subulate. Mericarp 4, oblong, 1.6–1.8(–1.9) × 0.8– 1 mm, triquetrous, bronze brown, nitid, muriculate, smooth to finely reticulate, and glabrous.

Distribution, habitat and phenology:— Hyptis cualensis grows in the Pacific slopes of Sierra de El Cuale, and it is only known from the municipality of Puerto Vallarta, Jalisco (figure 1). It inhabits in open pine-oak forest with savannoid elements, from 1100–1227 m elevation. It shares habitat with Bejaria mexicana Benth. , Byrsonima crassifolia (L.) Kunth, Nolina sp. , Pinus maximinoi H.E.Moore , Quercus sp. , and Salvia ramirezii J.G.González , in higher elevations, and also with Quercus aristata Hook. & Arn. in lower elevations. It flowers and fructifies from February to May.

Etymology:— The name of Hyptis cualensis honors the mountain range to which it belongs: Sierra de El Cuale, which is a relevant spot of plant diversity in western Mexico, several novelties and species have been described from there in the last recent decades ( González-Gallegos & Castro-Castro 2012).

Taxonomic relationships:— Hyptis cualensis is morphologically similar to Hyptis rhytidea due to its habit as robust shrub, indumentum, coriaceous, lustrous leaves of similar shape and size, spiciform compact inflorescences composed of pedunculated cymes of sessile flowers, and corollas similar in shape, size and color (table 2). However, there are several differences between them that reveal H. cualensis as a distinct species. The floral bracts of H. cualensis are always linear except for those of the base of the inflorescence (vs. reduced leaves as floral bracts throughout the inflorescence), more flowers per verticillaster (7–10 vs. 3–7), shorter bracteoles [1.3–2.2 vs. 3.5–5- 4(–7.4) mm], smaller calyx tube in flower [1.6–2.5 × 1.6–2 vs. 2.4–2.9 × 2.5–2.6(–3) mm] and in fruit (3.1–3.5 × 2.5–2.7 vs. 7–7.4 × 3.5–3.8 mm), internal ring of hairs attached from teeth line to 1–2 mm below (vs. at the middle of calyx tube length), shorter calyx teeth in flower (0.8–1.3 vs. 2.5–4.5 mm) and in fruit (up to 1.5 vs. 7.3 mm), and all of them distinct till the base (vs. the three upper connate at its base, and the two lower distinct), and slightly smaller mericarps [1.6–1.8(–1.9) × 0.8–1 vs. (1.9–)2.5–2.6 × (1–) 1.4–1.6 mm]. Besides, H. rhytidea occupies a much wider geographical and ecological distribution, since it grows from Michoacán to almost southern Sonora (Ramamoorthy & Elliot 1998), dwelling in several different types of vegetation and elevation range (table 2). In contrast, H. cualensis is known of one locality in the Pacific slope of Sierra de El Cuale in Jalisco, with a narrow ecological distribution in terms of the types of vegetation and elevation range it occupies (table 2).

Hyptis rhytidea is one of two species assigned by Epling (1933b, 1941) to section Rhytidea . The similarity of H. cualensis to the former suggests it should be placed in the same section according to Epling’s proposal. Harley & Pastore (2012) treated section Rhytidea as unplaced in any of the genera they recognized, but stating that probably belongs to Condea Adanson (1763: 504) , since H. rhytidea was recovered as sister of Condea clade in the cladograms shown by Pastore et al. (2011). However, H. rhytidea was not sampled in that research. Furthermore, using the key to genera they provide leads to Mesosphaerum instead of Condea .

Conservation assessment:— Hyptis cualensis appears to be in danger of extinction, based on its restricted geographic distributional range and population size. No subpopulation estimated to contain more than 250 mature individuals, so it should be classified as endangered [EN, criteria C2a (i)] according to the IUCN (2008).

Additional specimen examined (paratypes):— MEXICO. Jalisco. Puerto Vallarta: Ojo de Agua , 100 m al SO de donde nace el arroyo "Las Trancas", 20º31’00.3”N 105º12’8.2”, 1219 m, 19 February 2013 (fl), A . Flores- Argüelles & A. R . Romero-Guzmán 644 ( IBUG!); Ojo de Agua , 2 km al SO de donde nace el arroyo "Las Trancas", 20º31’30”N 105º11’14.6”W, 1139 m, 30 April 2013 (fr) A . Flores-Argüelles & A. R . Romero-Guzmán 660 ( IBUG!); Ojo de Agua , aprox. 400 m de donde nace el arroyo "Las Trancas", siguiendo el cauce, 20º30’55.9”N 105º11’54.6”W, 1104 m, 25 August 2013 (fr), A . Flores-Argüelles & A. R . Romero-Guzmán 798 ( IBUG!) .

Figures

FIGURE 1. Distribution map of Hyptis pseudolantana (squares), H. cualensis (triangles), and H. macvaughii (dots) in Mexico.

FIGURE 2. Hyptis pseudolantana terminal spiciform inflorescences (A), cyme, calyx and corolla detail (B, D), and habit (C). Hyptis cualensis terminal spiciform inflorescences (E), pectinate opposite cymes, calyx and corolla detail (F, G), and infructescence (H).

FIGURE 3. Hyptis cualensis holotype.