Euphorbia indica Lamarck, Encycl.

Mugnai, Michele, Lazzaro, Lorenzo, Nuzzo, Luca Di, Foggi, Bruno, Viciani, Daniele & Ferretti, Giulio, 2021, Synopsis of Euphorbia section Anisophyllum (Euphorbiaceae) in Italy, with an insight on variation of distribution over time in Tuscany, Phytotaxa 485 (1), pp. 1-65 : 26-29

10. Euphorbia indica Lamarck, Encycl. 2(2): 423. 1788.

Type (lectotype, here designated):—[s.l.]. s.d., s.c. s.n. (P-LA00563374 image!), http://mediaphoto.mnhn.fr/media/ 15224143802504Dpg9JkuCjPsOfBs

≡ Chamaesyce indica (Lam.) Croizat (1942: 406)

≡ Euphorbia hypericifolia subsp. indica (Lam.) Pignatti (1982: 35) , comb. inval.

= Euphorbia granulata var. decumbens Forsskål (1775 : CXII). Type:—Not found.

≡ Euphorbia decumbens (Forssk.) Willdenow (1814: 27)

= Euphorbia bracteolaris Boissier (1860: 8) . Type :— INDIA. Nilghensis melì avec 1832, s.d., G.S. Perrottet 1832 (holotype G00421042 image!), Fig. 17

≡ Euphorbia hypericifolia var. bracteolaris (Boiss.) Ewart (1907: 41)

Description:—Herbs, annual, with fibrous root. Stems erect to ascending, often purplish, with sparsely white pubescence. Leaves opposite; stipules triangular, laciniate, 1.5 mm; petiole to 3 mm; blade ovate, 3(–7) × 1.5(–2.5) cm, base obliquely rounded, margin obscurely toothed, apex rounded, adaxially almost glabrous, abaxially glaucous. Cyathia in axillary or terminal pedunculate capitate cymes; peduncle to 30 mm. Involucre cuplike, 1 × 1 mm, pubescent, marginal lobes triangular, apex acute; glands 4, green, rounded, diameter up to 1 mm; appendages white. Staminate flowers slightly exserted. Pistillate flowers: exserted from involucre; ovary pubescent; styles free; stigma deeply 2- lobed. Capsules 3-angular-ovoid, 1.5 × 2.0 mm, smooth, pubescent; fruiting pedicel 1.5 mm. Seeds reddish brown, ovoid-tetragonal, 1 × 0.75 mm, obscurely transversely furrowed.

Iconography:— Pahlevani & Riina (2011: 310, Fig. 4 ), Raju & Rao (1979: Figs. 1–8), Fig. 18.

Chromosome number:—Unknown.

Ecology:—Accidentally dispersed by humans as contaminant; globally considered as weed of cereals, cotton, orchards and pastures. Species typical of disturbed areas, either seasonally inundated or irrigated and often with impeded drainage ( Ma & Gilbert 2008).

Alien status:—Neophyte species native to tropical and western Asia, and China, it can be considered naturalized in tropical Africa, Caucasus and Arabian Peninsula.

Occurrence in Italy:—Absent. Recorded by mistake in LOM and VEN.

Taxonomic annotations:—In Europe E. indica was recorded for the first time by Wikus & Pignatti (1954), in Austria (Klagenfurt railway station) and Italy (Varenna railway station). These records were confirmed by Pignatti (1955), and by Pignatti (1982) under the name E. hypericifolia subsp. indica . Argenti et al. (1986) reported a second occurrence of E. indica in Italy for VEN (Feltre and Ponte alle Alpi railway stations). According to Hügin (1998b) and Banfi & Galasso (2010), all Italian records correspond to E. nutans . Euphorbia indica was consistently confused with related New World species (especially with E. hypericifolia ) although latters are completely glabrous, with smaller capsules and seeds with more pronounced ornamentations (Thellung in Graebner 1917, Raju & Rao 1979).

Type designations:—In the protologue of E. indica , no herbarium specimen is indicated, but only the locus classicus is mentioned together with the annotation “[...] nous a été communiqué par M. Sonnerat”. We searched for possible type material in P, P-LA and G, herbaria where Lamarck’s exsiccata are preserved. We did not find any specimen of E. indica directly linked to Sonnerat. Nevertheless, in Lamarck’s collection (P-LA) we could find a specimen of E. indica (P-LA00563374), bearing labels with Lamarck’s handwriting. Even if this specimen lacks any collection data, it consists in the most suitable herbarium material for the lectotypification.

We searched for original material of E. granulata var. decumbens in C, where is conserved most of Forsskal collection, but we could not find any specific specimen directly linkable with the protologue (i.e we found 3 specimens collected in Yemen by Forsskal, but they are simply labelled as E. granulata without any reference to E. var. decumbens ).

In the protologue of E. bracteolaris, Boissier (1860) referred to a specimen collected in India by Perrottet, being part of collection number 1832 (“ Perrottet sub n° 1832 ex parte”). Consulting the online herbarium of G, we retrieved two exsiccata collected by Perrottet in India and linked to collection number 1832. One is the holotype of Euphorbia pycnostegia Boissier (1860: 9) ( G 00441459 image!), which reports the original Perrotet’s label with collection number 1832. The other one ( G 00421042) is labelled in Boissier handwriting as “Perrotet. Nilghensis melì avec 1832”. This specimen undoubtofylly matches to the second part of Perrotet’s collection 1832 cited by Boissier in the protologue (probably divided by Bossier himself), as proved by the label, and thus corresponds to the holotyoe of E. bracteolaris .

Figures

FIGURE 4. Dorsal and lateral views of seeds:A) E. chamaesyce, B) E. glyptosperma, C) E. hirta, D) E. humifusa, E) E. humistrata, F) E. hypericifolia, G) E. hyssopifolia, H) E. indica, I) E. maculata, J) E. nutans, K) E. ophthalmica, L) E. peplis, M) E. prostrata, N) E. serpens subsp. serpens, O) E. thymifolia. Scale bars = 1 mm.