Decalepidanthus primuloides (Decne.) Dickoré & Hilger 2015

Dickoré, W. Bernhard & Hilger, Hartmut H., 2015, Decalepidanthus (Boraginaceae) includes and antedates Pseudomertensia; a synopsis of the genus, Phytotaxa 226 (2), pp. 131-143 : 138-139

5. Decalepidanthus primuloides (Decne.) Dickoré & Hilger , comb. nov.

Basionym:— Eritrichium primuloides Decne. in Jacquemont (1844: 123). ≡ Mertensia primuloides (Decne.) Clarke (1883: 171) . ≡ Pseudomertensia primuloides (Decne.) Riedl in Rechinger (1967: 62). ≡ Pseudomertensia moltkioides var. primuloides (Decne.) Kazmi (1970: 382) . Type:— INDIA. Jammu & Kashmir: ‘Ad rupes in locis excels, Pir Pundjâl’, 21 June 1831, V.Jacquemont 524 (holo P photo!, iso K! [Pir Panjal, s.n.]).

= Mertensia tibetica Clarke (1883: 171) . Lectotype (designated here):— PAKISTAN. Gilgit-Baltistan : Karakorum [Skoro La to Askole], 14000 ft., 12 August 1876, C.B.Clarke 30440 (K!, isolecto BM!). Remaining syntype:— PAKISTAN. Karakorum [Skoro La], 15500 ft., 8 August 1876, C.B.Clarke 30230 (K!).

= Mertensia nuristanica Rechinger (1951: 56) . Lectotype (designated here):— AFGHANISTAN. Kunar: Nuristan, Urura-Passhöhe, beiderseits oberhalb der Waldgrenze, 3900 m [incorrectly given as “ 2900 m ” in the protologue], kleine rasige Polster bildend, 9 August 1951, H.F.Neubauer 574 (W! individuals in the capsule). Remaining syntype:— AFGHANISTAN. Same locality, H.F.Neubauer 601 (W!, mounted individual). Both numbers are mounted together on one sheet. The lectotype chosen here, tentatively, define the individuals in the capsule, which probably refer to Neubauer 574, and comprising typical D. primuloides . The other specimen, mounted and probably referable to Neubauer 601, is a relatively large and possibly aberrant individual, but which still probably corresponds to D. primuloides .

Icon.: — Riedl (1963b): fig. 181, 184 ( Mertensia primuloides ); fig. 183 ( M. tibetica ). Ovczinnikov & Czukavina (1978): fig. 1 ( Pseudomertensia primuloides , flower).— Fig. 1d (nutlet), 1g (habit).

Distribution: —?SE Tajikistan (Gorno-Badakhshan: see D. rosulatus ), E Afghanistan (Kunar), N Pakistan (Khyber Pakhtunkhwa: Chitral; Gilgit-Baltistan), NW India (Jammu & Kashmir, Himachal Pradesh):?Southwest Pamir, west, southwest and south-central Karakorum, northwest inner Himalaya.—Map: fig. 2c.

Habitat: —Elevation (2950–)3620–4790(–5000) m, subalpine to alpine; scattered, locally abundant in open turf, near snow patches or in dwarf-scrub ( Carex borii Nelmes , Kobresia karakorumensis Dickoré , Bistorta affinis (D.Don) Greene ), on rock-ledges and in fissures of rock, among boulders, in semi-stabilized scree ( Carex nivalis Boott ), often somewhat shaded; rarely at relatively lower altitudes in forest ( Betula jacquemontii ) and on moist, shaded rocks.

Notes: — Decalepidanthus primuloides is a very pretty, conspicuous and usually distinctive plant, which often forms dense low ‘cushions’. It reaches to the highest elevations within the genus (4790 m, an old record from 5000 m seems inaccurate). D. primuloides is is still quite variable, and plants from sheltered, shady situations, or at lower altitudes, may grow more laxly and with a scape or few-leaved stem of up to ca. 20 cm tall. The leaf indumentum is usually thin, of short appressed trichomes, often almost glabrescent, but plants from the outer Himalayas may also have a relatively dense and ± patent indumentum. Flower dimensions also seem quite variable. The corolla tube is the potentially longest of the genus and often distinctly longer than in D. moltkioides and D. echioides . Corolla tube length of D. primuloides , however, is extremely variable, and ranges from ca. 8 to 25 mm. For potential morphological overlap with D. moltkioides or D. echioides , see under these species. Especially on the northwestern edges of their geographical ranges, with limited herbarium material from scattered populations and fruit often absent, the separation of D. primuloides from D. echioides might become problematic.

Confusion between or merging of Decalepidanthus moltkioides and D. primuloides was discussed under the former species. Eritrichium primuloides had been described from an area where both species occur, but probably from a relatively high elevation. However, it was usually not considered distinct from what is now Decalepidanthus moltkioides . While Clarke (1883) probably misinterpreted Mertensia primuloides for D. echioides , his new description of Mertensia tibetica is insofar reasonable as he probably intended to distinguish a distinct alpine species from the ‘usual lower-altitude Kashmir plant’ ( D. moltkioides ). The epithet ‘ tibetica ’ is misleading. As for many nineteenth’s century species, it referred to Baltistan (now Pakistan: Gilgit-Baltistan; otherwise and more commonly so, to ‘Little Tibet’, now India, Ladakh, part of Jammu & Kashmir). As yet, the genus Decalepidanthus seems to be unknown from Tibet and China, while D. echioides and D. primuloides both occur close to southwest borders of Xinjiang and Tibet / Xizang.

Figures

FIGURE 1. a–d Nutlets of Decalepidanthus species, adaxial face (left), abaxial face (right): a, D. echioides, Pakistan, Hunza, G. & S. Miehe 2811 (MSB); b, D. elongatus, Pakistan, Kaghan Valley, W.B.Dickoré 13249 (MSB); c, D. parviflorus, Pakistan, Kaghan Valley, U. Schickhoff 106A (MSB); d, D. primuloides, Pakistan, Hunza, G. & S. Miehe 3703 (MSB); e–g Habit of Decalepidanthus species: e, D. echioides, Pakistan, Gilgit-Baltistan, Gilgit District, Jutial Nala, 2620 m, 31 August 1995, W.B.Dickoré 12227; f, D. elongatus, Pakistan, Khyber Pakhtunkhwa, Mansehra District, Mt. Makra W, 3840 m, 14 September 1995, W.B.Dickoré 13180; g, D. echioides, Pakistan, Khyber Pakhtunkhwa, Mansehra District, Mt. Makra top, 3880 m, 14 September 1995, W.B.Dickoré 13259.