Carex stenolepis Lessing, 1831

Elven, Reidar, Pedersen, A. Tiril M. & Bjorå, Charlotte S., 2017, The nomenclature of two hybrid taxa in Carex sect. Vesicariae (Cyperaceae) currently assigned as Carex rostrata var. borealis and Carex stenolepis, Phytotaxa 324 (1), pp. 63-72 : 64-65

Carex stenolepis Lessing is a misapplied name.

In recent decades the name Carex stenolepis has been almost uniformly assigned to a hybrid species between C. saxatilis and C. vesicaria ( Hylander, 1966, Jakobsen, 1980, Egorova, 1999, Reznicek & Ford, 2002, Jermy et al., 2007). Lessing (1831: 301) described C. stenolepis based on specimens sent to him by a Mr. Deutsch from “Torneå- Lappmark” in North Sweden and by M.N. Blytt from the “Umgegend von Trondhjem” in Trøndelag, Central Norway. Lessing’s diagnosis is extensive, but not sufficient to discriminate among several alternative taxa; he compared his C. stenolepis with C. pulla Goodenough (1797: 78 , now C. saxatilis ) and with C. rotundata , but not with C. rostrata (or C. rostrata var. borealis ).

Therefore, the assignment of the name C. stenolepis depends on identification or designation and study of type material. We have not been able to locate any of the material studied by Lessing. Lessing’s collections were mainly deposited in the Herbarium of the Botanic Garden and Botanical Museum in Berlin–Dahlem (B), where much of the collection was lost during World War II ( Schultze-Motel 1960, Hiepko 1987). Some duplicates from Lessing’s herbarium were found in Leiden (L) but specimens of C. stenolepis were not among them (as also noted by Jakobsen, 1980).

As for the two collectors mentioned, the Mr. Deutsch collecting plants in Torne lappmark in Sweden is unknown to us, and no specimens by this collector are present in Norwegian or Swedish herbaria ( Jakobsen, 1980). It is unlikely that there exist any duplicates of his Swedish collection. Mathias N. Blytt collected the plant we until now have named as C. stenolepis several times, especially in the Dovrefjell mountains well south of the Trondheim area, but the only year he collected in the interior parts of Trøndelag (“Umgegend von Trondhjem”) was in 1824. The specimen(s) that Lessing received must have originated from Blytt’s expedition to interior Trøndelag (the Stjørdalen area) in 1824. Blytt’s main collections are deposited in the Natural History Museum in Oslo (O) and are intact. He customarily sent duplicates of his collections to corresponding botanists throughout Europe. Among the collections in Oslo, we have found a single sheet which must be a duplicate of what Lessing received, an undated collection from “Størdalen: Skurdalsporten”, annotated as “ C. vesicaria –alpigena Fr.” This is his only known collection of this species group from the area and year in question. Blytt’s collections of other plants from the same locality are dated 24 Aug. 1824, and this is most probably the collection date for the Carex specimen. The specimen is morphologically in accordance with Lessing’s description, and is with near certainty a duplicate of the collection Lessing had available, and is thereby an isosyntype according to ICBN Art. 9.3 ( McNeill et al. 2012), stating that the original material “comprises … (c) the isotypes or isosyntypes of the name irrespective of whether such specimens were seen by either the author of the validating description or diagnosis or the author of the name.” It is accordingly syntype material within the definitions of the Code. It was proposed as the only available type specimen by Jakobsen (1980). There may, however, be specimens from the same collection trip and area in other herbaria. One candidate is the specimen V- 176311 in UPS, annotated as “ Carex isolepis [!] Lessing” in Blytt’s handwriting (indicating that he had received a message back from Lessing albeit misspelling the name), but there is no locality or year given for this collection. It is morphologically nearly identical with the specimen in O and most probably from the same collection. On this background we here designate the specimen in O, with locality information in Blytt’s handwriting, as lectotype for the name C. stenolepis .

Although Blytt’s plant from “Størdalen”, and also the collection V- 176311 in UPS, are in accordance with Lessing’s description, they are not hybrids between C. saxatilis and C. vesicaria . Neither do they correspond to Fries’ C. vesicaria var. alpigena ( Fries, 1843:142) , a name belonging to the hybrid in question, as concluded by Jakobsen (1980) and confirmed by the type specimen (UPS!). Blytt’s specimens have distinct whitish dots (papillae) on the leaves, a feature characteristic for C. rostrata but absent from C. saxatilis and C. vesicaria and also from the plants currently denoted as C. stenolepis . In addition, they have narrow, acute pistillate scales, and fairly large utricles gradually narrowed into a long, forked beak ( Fig. 2c ); both features shared with C. rostrata and C. vesicaria but neither with C. saxatilis nor with plants currently denoted C. stenolepis . We identify Blytt’s plant as C. rostrata , albeit short-grown. Thus, following our type designation, the name C. stenolepis Lessing becomes a synonym of C. rostrata and unavailable for a hybrid taxon of a C. saxatilis × C. vesicaria origin.

The hybrid species, which Jakobsen (1980: 114) showed to have a wide range in Fennoscandia and Scotland and with a comparatively uniform morphology throughout this range, needs a binomial name. From Scotland this hybrid species is reported as C. × grahamii Boott (1844: 215–216 , see, e.g., Jermy et al., 2007, Stace et al., 2015). Jermy et al. (2007) and Stace et al. (2015) cited C. stenolepis auct., non Lessing, as a synonym of C. × grahamii , thereby implying that the name C. stenolepis Lessing is inappropriate. We do not know the reasons for this assumption, but as our findings show, the assumption is confirmed. From European Russia the hybrid species in question was reported by Kreczetowicz (1935) from the Karelia –Murman area under the name C. × grahamii and by Egorova (1999) from the Murman area and the northern Urals under the name C. stenolepis . There are also reports from North America (see below).

At rank of species, four names have been proposed for hybrids with the assumed parentage of C. saxatilis × C. vesicaria , namely: C. × grahamii , C. × ewingii , C. × mainensis , and C. × anticostensis . We discuss each of these names in the following.

Figures

FIGURE 2. Lectoype of Carex stenolepis Lessing, designated here, from Norway: Nord-Trøndelag, Meråker. From Oslo Herbarium (O). The plants belong to a short grown form of C. rostrata. A, habit; B, pistillate spike; C, utricle.