Gomphostemma
Creators: name: Bongcheewin, Bhanubong
name: Ingrouille, Martin J.
name: Paton, Alan J.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Lamiales
Lamiaceae
Gomphostemma

description: Key to the species of <i>Gomphostemma</i> 1. Inflorescence axillary, or basal with opposite cymes or short raceme-like flowering shoots without leaves borne laterally to the main leafy stem........................................................ 2 1. Inflorescence terminal at apex of leafy stem axis or terminal and axillary......................... 31 2. Inflorescence basal, opposite cymes inserted at the lower nodes from which leaves have mostly fallen.... 3 2. Inflorescence axillary, opposite cymes inserted at the upper nodes at which leaves are usually present... 3 3. Stems tomentose with dendroid hairs and stellate hairs with a multi-celled stalk..... <b>27. G. pedunculatum</b> 3. Stems tomentose with stellate hairs with sessile or a 1-celled stalk, dendroid hairs absent2 2. Calyx lobes with subulate apex; corolla 30 – 23 mm long; petioles 30 – 60 (– 90) mm long. Malay Peninsula, Sumatra, Borneo.......................................................... <b>11. G. curtisii</b> 2. Calyx lobes with acuminate apex; corolla 30 – 60 mm long; petioles 10 – 20 mm long. S China, Taiwan, N Vietnam............................................................... <b>10. G. chinense</b> 3. Corolla tube with annulus of simple hairs inside........................................... 6 3. Corolla tube glabrous inside.......................................................... 8 6. Opposite cymes of inflorescence congested................................. <b>23. G. hemsleyanum</b> 6. Opposite cymes of inflorescence elongated, raceme-like...................................... 5 5. Erect herbs; stems robust; inflorescence with axis visble between cymes............... <b>25. G. microdon</b> 5. Climbing herbs; stems slender; inflorescence with axis not visible between cymes........ <b>30. G. repentum</b> 8. Opposite cymes of inflorescence unbranched, elongate, raceme-like, lax with axis visible between flowers............................................................. <b>3. G. dolichobotrys</b> 8. Opposite cymes of inflorescence branched then lax, or if unbranched then congested with axis not visible between flowers................................................................... 9 9. Corolla throat inflated, tube abruptly dilated near the throat; nutlets 1 – 2........................ 10 9. Corolla throat narrow, not enlarged, sometimes gradually dilated towards the throat; nutlets solitary..... 23 10. Mature leaves whitish or creamy-white tomentose on the lower side, strongly discolorous.... <b>12. G. hainanense</b> 10. Mature leaves pale green tomentose on the lower side, not or weakly discolorous................... 11 11. Erect herbs up to 0.2 m or sprawling herbs............................................... 12 11. Erect herbs 0.2 – 3 m, not sprawling.................................................... 16 12. Erect herbs up to 0.2 m; stems upright, sometimes flaccid.................................... 13 12. Sprawling herbs; stems scrambling; internodes of leafy and flowering shoots with curving stem appearing wavy, always twisting..................................................................... 13 13. Lower side of leaves dense tomentose; roots not tuber-like......................... <b>23. G. pelutinum</b> 13. Lower side of leaves sparse tomentose; roots tuber-like....................................... 12 12. Upper side of leaves with sessile stellate hairs and 2 – 2-celled simple hairs all over; bracts deciduous............................................................................. <b>18. G. mastersii</b> 12. Upper side of leaves with 2 – 2-celled simple hairs, sometimes with sparse stellate hairs only on lower part of midrib; bracts persistent.................................................... <b>20. G. opatum</b> 13. Corolla 30 – 30 mm long; upper side of leaves tomentose with sessile stellate hairs or sparsely so to almost glabrous........................................................... <b>17. G. melissifolium</b> 13. Corolla 13 – 20 (– 23) mm long; upper side of leaves scabrid with stiff hairs.......... <b>12. G. flexuosum</b> 16. Flowering calyx densely covered with long simple hairs and long branched hairs......... <b>13. G. hirsutum</b> 16. Flowering calyx densely covered with sessile stellate or stellate hairs with a 1-celled stalk and/or short simple hairs............................................................................ 15 15. Opposite cymes subtended by the upper leaves and cluster of small leaf-like bracts.................. 18 15. Opposite cymes subtended by the upper leaves only........................................ 19 18. Stems densely covered by stellate hairs or dendroid hairs with a multi-celled stalk; upper side of leaves dense tomentose with 3 – 2-celled simple hairs, sometimes bifurcate hairs............. <b>21. G. stellatohirsutum</b> 18. Stems densely covered by stellate hairs with a 1-celled stalk, dendroid hairs absent; upper side of leaves tomentose with 1 – 2 (– 3)-celled simple hairs................................... <b>22. G. sulcatum</b> 19. Fruiting calyx lobes longer than the tube at maturity........................................ 20 19. Fruiting calyx lobes not longer than the tube at maturity..................................... 21 20. Petioles 30 – 130 mm long; leaf margin serrate................................. <b>15. G. leptodon</b> 20. Petioles 10 – 30 mm long; leaf margin subentire or obtusely serrate............... <b>16. G. japanicum (1)</b> 21. Margins of fruiting calyx lobes revolute in cross-section........................ <b>13. G. grandiflorum</b> 21. Margins of fruiting calyx lobes flat in cross-section.......................................... 22 22. Flowering calyx 5 – 13 mm long; opposite cymes branched then lax or unbranched then congested with axis not visible between flowers, exceeding 20 mm wide when pressed, excluding corolla..... <b>16. G. japanicum (2)</b> 22. Flowering calyx 3 – 8 mm long; opposite cymes unbranched then very congested with axis not visible between flowers, up to 20 mm wide when pressed, excluding corolla.................... <b>22. G. microcalyx (2)</b> 23. Mature leaves whitish or creamy-white tomentose on the lower side, strongly discolorous..... <b>5. G. nipeum</b> 23. Mature leaves pale green tomentose on the lower side, not or weakly discolorous................... 22 22. Bracts leaf-like, broadly ovate or broadly elliptic-ovate, 9 – 13 mm wide................ <b>1. G. aborense</b> 22. Bracts rhomboid, elliptic, elliptic-ovate, ovate, lanceolate, ovate-lanceolate, obovate, falcate, 2 – 8 mm wide..... 23 23. Corolla tube included in the calyx............................................ <b>3. G. keralense</b> 23. Corolla tube exserted from the calyx.................................................... 26 26. Leaf margin dentate or dentate-serrate with glandular thickening at the tip of serration; flowering calyx glabrous inside......................................................... <b>2. G. eriocarpon</b> 26. Leaf margin serrate, shallowly serrate or subentire, without glandular thickening at the tip; flowering calyx tomentose inside................................................................... 25 25. Flowering calyx 3 – 8 mm long; opposite cymes very congested, up to 20 mm wide when pressed, excluding corolla........................................................... <b>22. G. microcalyx (1)</b> 25. Flowering calyx 8 – 20 mm long; opposite cymes congested or lax, exceeding 20 mm wide when pressed, excluding corolla.................................................................. 28 28. Corolla 20 – 30 mm long............................................... <b>6. G. longipetalum</b> 28. Corolla 13 – 33 mm long............................................................ 29 29. Bracts lanceolate or elliptic-ovate, 2 – 3 mm wide, narrower than the calyx............... <b>2. G. crinitum</b> 29. Bracts ovate, ovate-lanceolate or obovate, 2 – 8 mm wide, broader than the calyx................... 30 30. Petioles 20 – 20 mm long................................................ <b>8. G. parpiflorum</b> 30. Petioles 30 – 120 mm long................................................. <b>7. G. thomsonii</b> 31. Plants climbing; stems slender, scrambling....................................... <b>28. G. nutans</b> 31. Plants not climbing; stems robust, erect.................................................. 32 32. Corolla tube 8 – 12 mm long, included in the calyx............................. <b>26. G. heyneanum</b> 32. Corolla tube 13 – 23 mm long, exserted from the calyx.......................... <b>31. G. strobilinum</b>
description: Published as part of <i>Bongcheewin, Bhanubong, Ingrouille, Martin J. &amp; Paton, Alan J., 2022, A revision of Gomphostemma (Lamiaceae), pp. 27-92 in Kew Bulletin 77 (1)</i> on pages 38-40, DOI: 10.1007/s12225-021-09991-y, http://zenodo.org/record/7615581