Culcitium discolor

Calvo, Joel, Benítez, Guillermo, Granda, Arturo & Beltrán, Hamilton, 2022, On the identity and typification of Raimondi’s names Culcitium discolor and Cryptochaete andicola (Compositae), Candollea 77 (1), pp. 1-8 : 3-7

Culcitium discolor

Culcitium species are nowadays widely accepted as belonging to Senecio . As circumscribed by CUATRECASAS (1950), the section Culcitium (Bonpl.) Cuatrec. includes scapiform perennial herbs with basal leaves in rosette or pseudorosette characterized by having discoid and nodding capitula with usually numerous supplementary bracts that confer an appearance of multiseriate involucre. Culcitium discolor was described as a simple-stemmed plant covered by glandular-pubescent indumentum. RAIMONDI (1857: 186) stated that his new species thrived in the summits of the Peruvian Andes, and could be distinguished from the other species of the genus by its discolorous leaves, which are green above and purple beneath.

The name Culcitium discolor has recently been synonymized with Senecio tephrosioides ( MOLINARI-NOVOA, 2021) , a species glabrous or sparsely pubescent (sometimes with arachnoid indumentum on the stem) characterized by displaying basal leaves attenuate into a pseudopetiole and synflorescences with several capitula (not solitary); it is known under the vernacular name “Huamanripa” ( SOUKUP, 1987; BLANCO-OLANO et al., 2020). These characters are in conflict with the original description, which describes the plant as glandular-pubescent,

having long-petiolate, subcordate basal leaves, and one to several capitula. Indeed, among the Peruvian species belonging to the scapiform culcitioid species, only S. rhizomatus is characterized by displaying the combination of characters provided in the protologue. Moreover, it can be readily separate from its allied species by the glandular-pubescent indumentum covering most parts of the plant (see CABRERA, 1985; SALOMÓN et al., 2018).

Raimondi specified that Culcitium discolor was known under the vernacular names “Janca-huasa” or “Ticlla-huasa” and gave further information on its medicinal properties. HERRERA (1919, 1921) treated C. discolor as an accepted species and cited it from the Paucartambo Province, providing the vernacular name “Tticllai-huarmi” besides “Ticlla-huasa” (previously compiled by Raimondi and by Herrera himself in minor notes). HERRERA (1935) subsequently stated that C. discolor corresponded to Senecio rhizomatus although no specimen was cited; it should be considered as an informal synonymy. Raimondi noticed that the natives attributed vulnerary properties to Culcitium discolor . Although we are aware that this medicinal virtue is scarcely specific, it would agree with the properties currently granted to Senecio rhizomatus ; it is used in Peru mainly as wound healing to treat dog bites, acne, and furuncles ( SOUKUP, 1987; DELGADO SÚMAR, 1988), but also to heal internal wounds and to increase biliary secretion ( HAMMOND et al., 1998; BLANCO-OLANO et al., 2020). This species has been studied for its antimicrobial properties (in vitro, ethanolic extract; SOTO MONTOYA, 2015), but lacks of comprehensive and in-depth pharmacological or toxicological studies. ARELLANO (1992) mentioned that many precautions should be taken with this plant because it is toxic and produces serious liver disorders.

Therefore, the aforementioned morphological reasons for associating the name Culcitium discolor with Senecio rhizomatus are also supported by the additional information provided by Raimondi in the protologue. On this basis, both names are considered as synonyms, S. rhizomatus being the priority name.

Senecio rhizomatus Rusby in Mem. Torrey Bot. Club 6: 66. 1896.

Lectotypus (first-step designated by GREENMAN, 1938: 816; second-step designated by SALOMÓN et al., 2018: 27): BOLIVIA. Prov. Cochabamba: near snow-line, Mt. Tunari, 1891, Bang 1050 (NY [NY00259378] image!; isolecto-: BM [BM001024050] image!, E [E00417024] image!, G [G00356103]!, GH [GH00012192] image!, K [K000634156] image!, MO [MO714703] image!, NDG [NDG62982] image!, NY [NY00259377] image!, PH [PH00023550] image!, US [US00123460] image!, US [US00123461] image!).

= Culcitium discolor Raimondi, Elem. Bot. 2: 186. 1857 [non Senecio discolor (Sw.) DC., 1838 ].  Senecio discoloratus Cuatrec. in Fieldiana, Bot. 27: 43. 1950 [nom. nov.], syn. nov. Neotypus (designated here): PERU. Dept. Huancavelica: Llaccta-ccolloy, 5 km W de Conaica, 4150–4200 m, 18.III.1951, Tovar 236 (US [US01838266]!; isoneo-: USM-280820!). Fig. 2.

Vernacular names. – According to literature, “Janca-huasa” or its spelling variants (see, e.g. SOUKUP, 1987; PUELLES GALLO et al., 2010) and “Ticlla-huasa” are the most commonly used and widespread names. The name “Ticlla-huasa” (from “ticlla”, painted, and “huasa”, back) refers to the color of the abaxial leaf surface, which is usually purple-colored ( RAIMONDI, 1874).

Distribution and ecology. – This species is distributed from La Libertad Department in Peru to Cochabamba Department in Bolivia ( CABRERA, 1985; BECK & IBÁÑEZ, 2014).

Senecio rhizomatus is a floristic element of the puna vegetation that grows in exposed rocky places or grasslands at elevations of 3500–5000 m, usually in places temporarily covered by snow ( CABRERA, 1985; BELTRÁN & ROQUE, 2015).

Notes. – RUSBY (1896) cited two syntypes in the protologue of Senecio rhizomatus , i.e. Bang 1050 and Bang 1046. Regarding the latter, the author specified that it was apparently the same as 1050 and that it came from the same locality. GREENMAN (1938) selected the collection Bang 1050 as the type of the name S. rhizomathus and excluded the collection Bang 1046 (identified as S. klattii Greenm. by him). This action should be accepted as the first-step lectotype of the name S. rhizomatus because the collection consists of more than a single specimen. CABRERA (1985) later designated the Bang material in NY as the lectotype, however, two specimens of this gathering are kept at NY. The second-step lectotype was finally fulfilled by SALOMÓN et al. (2018), who narrowed the typification to a single specimen. On the other hand, there is no consensus on the identity of Bang 1046. CABRERA (1985) identified it as S. rhizomatus , whereas GREENMAN (1938) indicated that it corresponded to S. klattii . This collection is not fully developed, what hinders its identification, but the basal leaves, stems, and involucres do not have the typical glandular-pubescent indumentum that S. rhizomatus displays. With regard to S. klattii , the available picture of the original material (most likely destroyed in B) shows a coarse stem base covered of leaf base remnants, which does not match the delicate stem base of Bang 1046. Moreover, S. klattii is a species that seems to be restricted in the Peruvian department of Ancash (see, e.g. Smith et al. 12335) that has never been recorded in Bolivia ( BECK & IBÁÑEZ, 2014). Therefore, we believe that further collections from Tunari (Cochabamba, Bolivia) are needed to resolve this issue.

[USM-302354; © Museo de Historia Natural, Universidad Nacional Mayor de San Marcos]

[ US 01838266; © United States National Herbarium]

A neotype is designated for Culcitium discolor in order to remove any uncertainty surrounding the application of this name. The selected specimen is a Tovar collection from northern Huancavelica Department, in central Peru. This is a suitable specimen because all the diagnostic characters can be easily studied, but also because the label contains information about the vernacular name (“Llanga-huasa” [spelling variant of Raimondi’s “Janca-huasa”]) and the vulnerary properties of the plant (“Utilizan para curar heridas” [used to heal wounds]) .

As originally circumscribed ( RUSBY, 1896; CABRERA, 1985), Senecio rhizomatus is a scapiform perennial herb that reaches 0.4 m tall and is characterized, among other characters, by having persistent, long-petiolate basal leaves arranged in pseudorosette; see CABRERA (1985) for further details on the complete synonymy of the name. SALOMÓN et al. (2018) also treated the Ecuadorian species S. eliseae J. Calvo as a new synonym. This is a suffrutescent herb up to 1.5 m that is leaved only on the upper half. Among other characters, these species also differ in synflorescence type (cymose, lax, composed of 1–5 capitula in S. rhizomatus vs. pseudocorymbose, rather widespread, composed of (3–)7–10(–20) capitula in S. eliseae ), synflorescence bracts (linear-lanceolate, reduced in S. rhizomatus vs. foliose, similar to the upper cauline leaves in S. eliseae ), cauline leaves (decrease in size upward in S. rhizomatus vs. rather uniform in size in S. eliseae ), and leaf color (usually discolorous, purple-colored beneath in S. rhizomatus vs. concolorous, green on both surfaces in S. eliseae ). In addition, S. eliseae thrives in very humid shrubby paramos at elevations of 3200–3550 m ( CALVO, 2015), which does not match the aforementioned habitat and ecology of S. rhizomatus . Against this background, no reason supports their synonymy.

According to the herbarium identifications, we realized that Senecio rhizomatus has been confused with S. hyoseridifolius Wedd. , a taxon known only from Peru. Both species display most parts of the plant covered by a glandular-pubescent indumentum and they have a similar synflorescence architecture and capitulum type. However, S. hyoseridifolius has runcinate to pinnatipartite leaves with rather distantly dentate lobes. The cauline leaves are large (especially the lower ones) and do not abruptly decrease in size upward as in S. rhizomatus . The basal leaves are shortly petiolate and usually wither early.