Solanum hovei Dunal, Prodr. [A. P. de Candolle] 13(1): 311. 1852.

Aubriot, Xavier & Knapp, Sandra, 2022, A revision of the " spiny solanums " of Tropical Asia (Solanum, the Leptostemonum Clade, Solanaceae), PhytoKeys 198, pp. 1-270 : 1

18. Solanum hovei Dunal, Prodr. [A. P. de Candolle] 13(1): 311. 1852.

Figs 2E , 4B , 31

Solanum jacquemontii Dunal, Prodr. [A. P. de Candolle] 13(1): 287. 1852. Type. India. Sin. loc., V.V. Jacquemont 563 [593 in protologue] (lectotype, designated here: MPU [MPU858235]; isolectotype: P [P00049910]).

Type.

India. Gujarat: Ahmedabad district , Dolca [Dholka] near Sabermatty, A.P. Hove s.n. (holotype: BM [BM000900293]) .

Description.

Subshrubs to shrubs, to 1.5 m tall, armed. Stems erect, terete, prickly, sparsely stellate-pubescent; prickles to 7 mm long, to 3.5 mm in diameter at the base, straight to slightly recurved, broad-based, laterally compressed, light orange to brown, glabrous; pubescence of mixed sessile and short-stalked porrect-stellate trichomes, the stalks ca. 0.3 mm long, the rays 4-8, ca. 0.3-0.4 mm long, the midpoint up to 0.3 mm long; new growth sparsely to densely stellate-pubescent; bark of older stems grey to pale greenish brown, glabrescent. Sympodial units difoliate, the leaves usually geminate. Leaves simple, shallowly lobed, the blades 5-21 cm long, 2-9 cm wide, ca. 2-3 times longer than wide, rhombic to subelliptic, chartaceous, discolorous, armed along the central and occasionally the lateral veins, the prickles to 1 cm long, to 2 mm at the base, straight, flattened, often tinged with purple at the base in live plants; adaxial surface dark green, moderately to sparsely stellate-pubescent, the trichomes porrect, thick-stalked, the stalks to 0.2 mm, the rays 3-8, 0.1-0.4 mm long, the midpoint to 1 mm; abaxial surface light green, moderately to densely stellate-pubescent, trichomes a mixture of porrect and multangulate, sessile or short-stalked, the stalks to 0.4 mm, the midpoint and lateral rays relatively equal in length, ca. 0.3-0.4 mm; major veins 4-6 pairs; base cuneate to short attenuate, somewhat oblique; margins entire to shallowly lobed, the lobes 2-3 on each side, 0.1-0.5 cm long, triangular, broadly acute to obtuse, the sinuses less than 1/4 of the way to the midrib; apex narrowly acute; petiole 0.7-2.5 cm, ca. 1/10-1/5 of the leaf blade length, moderately to densely stellate-pubescent, prickly or sometimes unarmed, the prickles similar to those on the blades. Inflorescences 0.4-4 cm long, extra-axillary, unbranched, with ca. 4-10 flowers, 1-3 flowers open at any one time, moderately to densely stellate-pubescent, glabrescent, with a mix of sessile and short-stalked stellate-porrect trichomes like those of the stems, unarmed; peduncle ca. 0-1.3 cm long, unarmed; pedicels 5-9 mm long, ca. 0.5 mm in diameter at the base, ca. 1 mm in diameter at the apex, spreading at anthesis, unarmed or prickly with a few straight and broad-based prickles, sparsely to moderately pubescent with stellate-porrect trichomes like those of the stems, articulated at the base; pedicel scars spaced 0.5-8 mm apart. Buds ellipsoid to ovoid, exserted from the calyx before anthesis. Flowers 5-merous, apparently all perfect. Calyx with the tube 0.7-2.5 mm long, conical, the lobes 0.5-1.6 mm long, 1.3-2 mm wide, broadly deltate, unarmed or very sparsely prickly with straight to slightly recurved prickles, moderately to densely stellate-pubescent abaxially with porrect-stellate trichomes like those of the pedicels, sometimes purple-tinged on living plants. Corolla 1.2-1.5 cm in diameter, light blue or purple, rotate-stellate, lobed ca. halfway to the base, interpetalar tissue somewhat present, the lobes 4-5.5 mm long, 3-4 mm wide, ovate, spreading at anthesis, sparsely stellate-pubescent along the midvein and on the lower half of lobe adaxially, the hairs sessile, multangulate, moderately to densely stellate-pubescent abaxially, the hairs subsessile, porrect-stellate and multangulate. Stamens equal; anthers 4-5.5 mm long, 0.6-1.2 mm wide, orange or orangish yellow, connivent, glabrous, poricidal at the tips, the pores directed distally, not elongating to slits with drying; filament tube minute, glabrous; free portion of the filaments 0.3-0.4 mm long, glabrous. Ovary oblong-conical, moderately stellate-pubescent towards the apex; style 6-9 mm long, sparsely to moderately stellate-pubescent on proximal 2/3-3/4, the hairs sessile, porrect-stellate or multangulate; stigma subcapitate, the surfaces minutely papillose. Fruit a subglobose berry, 1-5 per infructescence, 0.6-1 m in diameter, orange when ripe, the pericarp thin and shiny, glabrous; fruiting pedicels 1-1.5 cm long, ca. 0.6 mm in diameter at the base, ca. 2 mm in diameter at the apex, strongly deflexed; fruiting calyx not markedly accrescent, the lobes 2-3 mm long, 1-1.5 mm wide, often breaking off in dry material. Seeds 10-20 per berry, 2.8-4.1 mm long, 2.2-3 mm wide, flattened reniform, yellowish brown, the surfaces minutely pitted, the testal cells with slightly sinuate margins. Chromosome number: not known.

Distribution

(Fig. 32 ). Solanum hovei is endemic to India and occurs primarily along the Western Ghats range in the states of Goa, Gujarat, Karnataka and Maharashtra with most of the collections of this species having been made in the surroundings of Mumbai and Pune.

Ecology and habitat.

Solanum hovei grows in open areas on plateaus and along roadsides and forest outskirts from 150 to 1,200 m elevation.

Common names and uses.

India. Goa: mothirigani ( Naithani et al. 1997).

Preliminary conservation status

( IUCN 2019). Least Concern (LC). EOO (173,911 km2, LC); AOO (564 km2, VU). Solanum hovei is a relatively common and widely distributed species in the Western Ghats biodiversity hotspot.

Discussion.

Solanum hovei is a member of a group of species identified in the molecular analyses of Aubriot et al. (2016a) as the ' S. violaceum group’. It is morphologically similar to the sympatric and widespread S. violaceum but differs from it in having leaves with more sparsely pubescent adaxial surfaces and cuneate (rather than acute or truncate) bases. The pedicels of S. hovei are strongly deflexed in fruit, while those of S. violaceum are spreading. Solanum multiflorum of western India also has strongly deflexed pedicels, but they are shorter, and the leaves are densely pubescent with longer trichomes.

Sen Gupta (1964) suggested S. hovei was a rare plant in the Western Ghats, but the number of recent collections in local herbaria suggest otherwise. It is probable that S. hovei was largely confused with S. violaceum in herbaria (usually identified as S. indicum ).

The protologue of S. jacquemontii ( Dunal 1852) cites duplicates of " Jacquemont 593 " in both P and MPU. The specimen we have selected as the lectotype has an annotation with this name in Dunal’s hand and is numbered " 563 ", we are treating this as an error to be corrected in the protologue.

Specimens examined.

See Suppl. materials 1-3.

Figures

Figure 2. Vegetative characters for tropical Asian spiny solanums A large and densely hairy repand leaf of S. lasiocarpum (Meeboonya et al. RM 287, Thailand) B small, pubescent, very shallowly lobed leaf of S. miyakojimense (field photograph, unvouchered, Taiwan) C entire, pubescent leaf of S. robinsonii (Nuraliev 3031, Vietnam) D glabrescent and deeply dissected leaf of S. virginianum (Sampath Kumar et al. 126968, India) E conical straight prickles on a pubescent young stem of S. hovei (field photograph, unvouchered, India) F strongly hooked prickles on a glabrous young stem and on the abaxial leaf surface of S. trilobatum (Meeboonya et al. RM 242, Thailand) G needle-like purple prickles on the adaxial leaf surface of S. cyanocarphium (field photograph, unvouchered, Vietnam) H pubescent young stem of S. barbisetum armed with prickles and bristles (Suksathan et al. PS 3832, Thailand). Photograph credits: A, B, D-F X. Aubriot C, G M. Nuraliev H D. Pedersen.

Figure 4. Diversity of fruits and seeds in tropical Asian spiny solanums A large oval fruit of Solanum insanum (Sampath Kumar et al. 126918, India) B condensed infructescence and small rounded fruits of Solanum hovei (field photograph, unvouchered, India) C large rounded hairy fruit of S. involucratum with strongly accrescent and spiny calyx (field photograph, unvouchered, Vietnam) D small rounded fruit of Solanum pubescens with elongated calyx lobes (Sampath Kumar et al. 126956, India) E rounded fruit of Solanum cyanocarphium with strongly accrescent and spiny calyx (field photograph, unvouchered, Vietnam) F small rounded fruit of S. trilobatum in transverse cut (Meeboonya et al. RM 242, Thailand) G rounded fruit and accrescent calyx of S. praetermissum in transverse cut (field photograph, unvouchered, Vietnam) H oval fruit of Solanum virginianum in transverse cut (field photograph, unvouchered, India). Photograph credits: A, B, D, F, H X. Aubriot C, E, G M. Nuraliev.

Figure 31. Solanum hovei Dunal A herbarium specimen (holotype) collected in India (Hove s. n., BM 000900293) B habit and leaves (field photograph, unvouchered, India) C detail of a fertile branch (field photograph, unvouchered, India) D detail view of a flower (field photograph, unvouchered, India) E detail view of a fruit (field photograph, unvouchered, India). Photograph credits: A CC-BY, © copyright The Trustees of the Natural History Museum, London B-E X. Aubriot.

Figure 32. Distribution of S. hovei.