吕亚媚 杜 凡 李 娟 肖明昆
(西南林业大学林学院,云南 昆明 650224)
海漆属约35种,分布于非洲,亚洲,澳大利亚,太平洋岛屿。中国有5种和2变种,产西南部经南部至台湾[1-2]。现代药理研究表明,海漆属植物中二萜类成分为其主要活性物质。近20年来,从该属植物中发现的154个二萜类成分,具有抗人类免疫缺陷病 (HIV)、抗炎等作用[3-4]。新种的发现不仅为研发新的抗HIV药物提供了可能,同时还丰富了元江县的狭域特有种,为元江县狭域特有种形成机制提供了新的研究材料。
2006年项目组到元江县进行考察,在西拉河初次采到新种标本,由于标本不全未能发表。于2017年4月再次去西拉河采集到完整标本。
元江海漆新种 (图1)
ExcoecariayuanjiangensisF. Du et Y. M. Lv, sp. nov. Fig. 1
Evergreen shrubs to small trees, 1.5-4 m tall, glabrous, sparsely lenticellate. Leaves nearly opposite, rarely alternate, subleathery, obovate or oblong, 9-14 × 3-4 cm; apex acute or acuminate, base wedge, margin indistinctly serrulate, spacing 3-10 mm, apex with glands; leaves bright, dried margin slightly curl; midvein slightly raised adaxially, obviously elevated abaxially, lateral veins 10 pairs or more, arcuated rise,margin distance ca. 3 mm disappeared, fine veins unobvious; grooved petioles 7-10 mm, 3-5 glands at the apex. Stipules caducous, broadly triangle, 3 × 2 mm, aristate at apex, acumen to 2 mm, margin with tassels, 0.3 mm. Flowers unisexual, androgynous; flowers densely aggregated into terminal and axillary catkins, up to 6.5 cm, rachides abscission leaving obviously scars on branches. Male flowers: pedicels ca. 1 mm; bracts on rachis, broadly triangle, ca. 2 × 2 mm, apex acute, base ventral surface with 1 gland per side, each bract with 1 flower; 2 bracteoles on pedicels, narrowly triangle, ca. 2 × 0.5 mm, apex caudate, each side base with 1 gland; sepals 3, lanceolate, 1.5 × 0.5 mm, base often with glands; stamens 3, free, anthers reniform, filaments slightly longer than anthers. Female flowers: 1-4 in inflorescence lower, pedicels ultrashort, elongation to 1 cm after fruit; bracts and bracteoles as in the male; sepals 3, broadly triangle, ca. 1 × 0.8 mm, ovary ovate, styles 3, free, revolute at apex. Capsules section triangular, ca. 1.2 cm in diam., carpels with ribs, obviously elevated; seeds ovate, striped, gray-black, ca. 5 × 4 mm. Fl. throughout year.
图1元江海漆
A. 果实;B. 雌花和1苞片2小苞片;C. 柔荑花序;D. 枝条;E. 苞片和2腺体
Fig.1Excoecariayuanjiangensis
A. fruit; B. female flower and 1 bract 2 bracteoles; C. androgynous; D. branch; E. bract and 2 glands
New species is related toE.acerifoliaDidr., differing in leaves evergreen, nearly opposite, subleathery, petioles longer, stipules broadly triangle; inflorescences sturdy and long, flowers densely aggregated, bracts apex acute, glands on the base ventral surface, anthers reniform; fruit ribs obviously elevated.
常绿灌木至小乔木,高1.5~4 m,全株无毛,疏生皮孔。叶近对生,少互生,薄革质,倒卵形或长椭圆形,长9~14 cm,宽3~4 cm;先端急尖至渐尖,基部楔形,边缘具不明显的疏浅锯齿,齿间距3~10 mm,齿端有腺体;叶面光亮,边缘干时略背卷;中脉上面略凸起,下面显著凸起,侧脉10对或更多,弧曲上升,离缘约3 mm处消失,细脉不明显;叶柄长7~10 mm,上面具深沟,近顶端处具3~5个腺体。托叶早落,阔三角形,长3 mm,宽2 mm,顶端芒尖,尖头长达2 mm,边缘具流苏,长0.3 mm。花单性,雌雄同序;柔荑花序,顶生和腋生,长达6.5 cm,花密集着生,花序脱落后枝上留下显著痕迹。雄花:花梗长约1 mm;苞片着生于花序轴上,阔三角形,长宽约2 mm,顶端急尖,基部腹面两侧各1腺体,每苞片内有1花;小苞片2,着生于花梗基部,狭三角形,长约2 mm,宽约0.5 mm,顶端尾尖,基部两侧各1腺体;花萼3,披针形,长1.5 mm,宽0.5 mm,其基部常具腺体;雄蕊3,分离,花药肾形,花丝略长于花药。雌花:1~4朵生于花序基部,花梗极短,果后伸长至1 cm;苞片和小苞片与雄花者相同;萼片3,阔三角形,长约1 mm,宽约0.8 mm;子房卵形;花柱3,分离,顶端外卷。蒴果截面三角形,直径约1.2 cm,果瓣具棱,显著凸起;种子卵形,灰黑色具斑纹,长约5 mm,宽约4 mm。全年开花。
新种与E.acerifoliaDidr.相近,不同点在于新种叶常绿、近对生、薄革质,叶柄较长,托叶阔三角形;花序粗且长,花着生密集,苞片顶端急尖,腺体位于腹面基部;花药肾形;果棱显著凸起。
云南 (Yunnan):玉溪市,元江县,西拉河村 (Yuxi City, Yuanjiang County, Xilahe Village),alt. 680 m,季雨林 (Monsoon Forest),2006-10-04,杜凡,王娟 (F. Du & J. Wang)Y3838;西拉河 (Xilahe River),alt. 620 m,季雨林 (Monsoon Forest),2017-04-23,杜凡,吕亚媚 (F. Du & Y. M. Lv) Y20170423 (Holotype, SWFC)。
新种分布范围狭窄,自2006年以来仅在元江河谷海拔800 m以下的湿热生境中发现。数量不多,分布点处于村寨边,人为干扰严重,应该加强保护。
致谢:云南元江国家级自然保护区管护局大力支持,项目组其他成员多次帮助,王凌女士为新种绘图,在此由衷感谢!
[参 考 文 献]
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[4] 曾涌, 罗建军, 何文生, 等. 海漆属植物二萜类成分及其药理活性的研究进展[J]. 中国药房, 2015, 26(28): 4020-4017.