Cucumis hystrix Chakrav.

De Wilde, Willem J. J. O. & Duyfjes, Brigitta E. E., 2007, The wild species of Cucumis L. (Cucurbitaceae) in South-East Asia, Adansonia (3) 29 (2), pp. 239-248 : 241-246

2. Cucumis hystrix Chakrav.

( Figs 2 ; 3 )

Journal of the Bombay Natural History Society 50: 869, pl. 7 (1952); Records of the Botanical Survey of India 17 (1): 110 (1959). — A. M. Lu & Zhi Y. Zhang, Flora Sinicae 73 (1): 207, f. 53 (1986). — J. H. Kirkbride, Biosystematic Monograph of the Genus Cucumis ( Cucurbitaceae) : 86 (1993). — S. K. Chen, Flora Yunnanica 6: 340, f. 88: 3-7 (1995). — Type: India, Assam, Garo Hills, Tura Mountain, II.1929, Parry 859 (holo-, K!).

Cucumis muriculatus Chakrav. , Journal of the Bombay Natural History Society 50: 869, pl. 4 (1952). — Type: Myanmar (Burma), Ruby Mines District , Lace 6325 (holo-, E!; iso-, E!).

MATERIAL EXAMINED. — Thailand. Northern , Doi Chiang Dao, 9.VIII.1935, Garrett 970 ( L) . — Northern , Doi Chiang Dao Animal Sanctuary, 7.XI.1995, Maxwell 95- 1106 ( L) . — Northern , Doi Chiang Dao, 12.IX.1967, Tagawa et al. T9853 ( BKF) . — Northern , Doi Chiang Dao, 15.IX.1967, Shimizu et al. T 10150 ( BKF, L) . — Northern , Doi Inthanon, 16.IX.2003, Phonsena et al. 3931 ( BKF, L) . — Northern , Doi Chiang Dao Wildlife Sanctuary, 23.XI.2004, Phonsena et al. 4463 ( BKF, L) . — Northern , Doi Sutep, 22.XI.1989, Maxwell 89-1436 ( L) . — Northern , Doi Sutep, 29.VIII.1988, Maxwell 88-1042 ( L) . — Northern , Doi Sutep, 26.XII.1987, Maxwell 87-1638 ( L) . — Northern , Doi Sutep, 12.IX.1987, Maxwell 87-985 ( BKF, L) . — Northern , Doi Sutep, 29.IX.1958, Sørensen et al. 5338 ( L) . — Northern , Doi Chiang Dao, 9.VIII.1935, Garrett 994 ( E, L) . — Northern , Doi Sutep, 26.VII.1914, Kerr 3301 ( E) . — Northern , Doi Chiang Dao, 18.XI.2005, Suddee et al. 2421 ( BKF, L) . — Northern , Doi Chiang Dao, 19.XI.2005, Suddee et al. 2505 ( BKF L) . — Northern , Jae Sawn, 10.VIII.1996, Panatkool 157 ( L) . — Northern , Jae Sawn, 26.X.1995, Maxwell 95-1021 ( BKF L) . — Northern , Jae Sawn, 23.VIII.1996, Maxwell 96-1119 ( BKF, L) . — Northern , Doi Kuhn Dahn National Park, 26.IX.1993, Maxwell 93-1126 ( L) . — Northern , Doi Phu Ka, 26.XI.2005, Phonsena et al. 4703 ( BKF, L) . — Northern , Doi Phu Ka, 19.IX.2003, Phonsena et al. 3963 ( BKF, L) . — Northern , Doi Wao, 10.IX.1995, Larsen et al. 46290 ( L) . — Northern , Doi Phu Ka, 18.IX.2003, Phonsena et al. 3941 ( BKF, L) . — Northern , Khao Pha Wo, 23.VII.1973, Murata et al. T 16912 ( BKF, L) . — Southwestern , 12.IX.2001, Kofman 300 ( L) . — Southwestern , Toong Yai Naresuan Wildlife Reserve, 7.X.1993, Maxwell 93-1158 ( L) . — Southwestern , 11.XI.2004, Pruesapan et al. 51 ( BKF, L) . — Southwestern , Huay Bankau, 12.XI.1971, Van Beusekom et al. 3717 ( BKF, L) .

DESCRIPTION

Annual climber 2-6(-8) m long; wholly (setose) hairy, hairs to 3 mm long; stem (1-) 2 mm diam.; monoecious. Tendrils: appressedly or patently hairy. Leaves: blade circular or ovate in outline, 5-15 cm diam., (3-)5-angular or shallowly lobed (to c. 1/3 deep), base deeply cordate, apex, and apices of lobes acute(-acuminate), margin regularly or irregularly serrate-dentate, both surfaces sparsely or densely finely (appressed) setose-hairy, especially on the veins; hairs brown-red or grey, mostly with thickened base, but cystoliths not obvious; petiole 1.5-8 cm long, with (appressed) downward-curved or subpatent hairs. Male flowers: 2-7-fascicled; pedicel 2-5 mm long, hairy; receptacle-tube turbinate-urceolate, c. 5 × 2 mm; sepals 2(-3) mm long; corolla 8-10 mm long, connate part 2-4 mm long, corolla lobes 4-6 mm long, apex (sub)acute, mid-veins setose-hairy; stamens inserted about halfway in the receptacle-tube; filaments c. 1 mm long, glabrous, anthers 2-2.5 mm long, connective extension (0.5-) 1 mm long; disc subglobose, c. 2 mm diam. Female flowers: solitary; pedicel 1-5 mm long (or longer, see the remarks), strigose; ovary narrowly ellipsoid-ovoid, 8-10 × 2-3 mm, antrorse-strigose, hairs with bulbose thickenings, grey or red-brown, c. 1 mm long; perianth as in male flowers, but sepals somewhat broader; style 2-3 mm long, stigma c. 2.5 mm long, consisting of 3 sessile carnose lobes, connate at base, lobes at apex 2-lobed, papillose; staminodes c. 1 mm long, inserted about halfway the receptacle-tube. Fruit: pendent, green or yellowish green, (narrowly) ellipsoid, tapering at both ends and apex shortly beaked, 3-5 × 1-2 cm, beak 2-5 mm long, aculeate tubercled by dense, soft, spine-like 2-5 mm long protuberances; fruiting pedicel 2-10 mm long (but see the remarks). Seeds: numerous, 3.5-5 × 2-2.5 mm, not ornamented, unmargined, smooth or hairy.

DISTRIBUTION AND PHENOLOGY

Cucumis hystrix occurs in NE India (Assam), Myanmar, SW China (Yunnan), and N and W Thailand; it has not yet been found in Laos. The species has been recorded on elevations between 200 and 1800 m in scrub vegetation, along roadsides and forest edges, over granite bedrock as well as on limestone. The fruits when fresh are (yellow-) green and to c. 6.5 cm long .

REMARKS ON VARIATION

Cucumis hystrix is quite distinct but shows much infraspecific variation. Although the collections at hand are most numerous from Thailand, we cannot formally describe this variation as we consider that collecting is still insufficient. Variation mainly concerns 1) the length and colour of the hairs on the stems, 2) the density of the hairs on the leaf blades, 3) the character and orientation of the hairs on the petioles, 4) the length of the pedicels of female flowers and fruiting pedicels, and 5) the density of the spiny tubercles or hairs on the fruits. In Thailand we found the following:

– The hairs on the stems can be grey, yellowish or red-brown, varying in length from 1 to 4 mm.

– The hairs on the petioles can be rather short, stiff and distinctly curved downwards, like in Mukia javanica (Miq.) C.Jeffrey ; this is found mainly in northern Thailand.The hairs on the petioles can also be longer and weaker and generally more patent. – The length of the pedicels of female flowers and fruiting pedicels can vary from a few millimeters to c. 10 mm. On Mt Chiang Dao, N Thailand, the fruits are mostly subsessile, while the flowers are comparatively large.

– The pedicels of the female flowers in the collection Phonsena et al. 3941 (BKF, L) from Mt Phu Ka, N Thailand, are c. 2 cm long, while the ovaries are almost glabrous, except for a few appressed, stiff hairs, without bulbous thickenings at base, reminding us of a wild form of C. sativus . However, true C. hystrix was found not far away from the former and the plants were similar in habit. More material is needed to assess the meaning of this variation.

Chakravarty (1952: pl. 4) depicts for his C. muriculatus ( India) – at present considered a synonym of C. hystrix following Jeffrey (1980a) and Kirkbride (1993) – the hairs on the petiole curved upwards, not downwards. Moreover, he depicts the anthers as being about as broad as long, whereas in C. hystrix from Thailand the anthers are much longer than broad. These discrepancies should be rechecked on the type of C. muriculatus in E.

Figures

FIG. 2. — Cucumis hystrix Chakrav.:A, B, node with male inflorescence;C, detail of lower surface of leaf blade;D, male flower,just expanding; E, male flower, opened; F1-F4, stamens, seen from inside and outside respectively; F1, F2, one-thecous stamen;F3, F4, two-thecous stamen;G, node with female flower;H, female flower;I, female flower,opened;J, node with fruit;K, seed.A-F,J, K, Phonsena, De Wilde & Duyfjes 3931; G-I, Phonsena, De Wilde & Duyfjes 3963. Scale bars: A, 2 cm; G, J, 1 cm; B, H, I, 3 mm; C, F1-F4, K, 1 mm; D, E, 2 mm.

FIG. 3. — Cucumis hystrix Chakrav.:A, male flower;B, C, female flowers from different individuals,differing in indumentum of the ovary; D, fruits. A, C, Phonsena, De Wilde & Duyfjes 3963; B, Suddee, De Wilde & Duyfjes 2421; D, Suddee, De Wilde & Duyfjes 2505.