I think the main difference appears to be in Calyx lobes: For *Mussaenda frondosa*, it is 'Calyx with hypanthium portion ellipsoid, 3-4 mm, strigose to sericeous; lobes narrowly triangular to narrowly ligulate, *7-12 mm,* hirsute, acute to acuminate' as per Flora of China <http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=220008890>. For M*ussaenda roxburghii*, it is 'Calyx lobes filiform, tapering from base, *6-9mm x 1mm, *densely covered in long silky hairs' as per Flora of Bhutan <https://biodiversity.bt/species/show/6298>.
Let us see the detailed description to arrive at the right id: Flora of Bhutan <https://biodiversity.bt/species/show/6298> Flora of China <http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=220008890> *Mussaenda roxburghii* Hook.f.: *Much branched shrub 1-4.5m.* stems glabrous or pilose with spreading hairs *leaves petiolate usually elliptic, rarely ovate or oblong,* *5-25 x 4-9cm,* acuminate at both ends, *subglabrous or thinly pilose above, thinly to densely pilose below, veins adpressed pilose on both surface; *petioles 2-15mm; *stipules broadly triangular, 6-10mm.* *Inflorescence a dense terminal head, usually 3 branched from base, but differentiated, many flowered. Calyx lobes filiform, tapering from base, 6-9mm x 1mm, densely covered in long silky hairs.* *Corolla tube 2.4-2.8cm, densely covered in long silky hairs. lobes narrowly ovate, 4-8 x 2-2.5mm, terminating in a long fine hairpoint. Berry globose, 6-10mm, glabrous calyx persistent until fruit is ripe.* *Mussaenda frondosa* Linnaeus: *Climbing shrubs; *branches terete to compressed, moderately to densely pale red sericeous to hirsute becoming glabrescent, red-brown or brown, rather densely lenticellate. Leaves opposite; petiole 4-10 mm, densely sericeous; blade drying thinly papery or leathery, adaxially dark green to brownish green, abaxially pale green to yellowed, *broadly elliptic, elliptic-oblong, ovate, or oblanceolate, 8-15 × 3-8* cm, *both surfaces sparsely strigillose on lamina and strigose to sericeous on principal veins, *base acute, obtuse, or rounded, apex acute to caudate-acuminate; secondary veins 7-10 pairs, tertiary venation visible and reticulate; *stipules persistent, triangular, 5-10 mm, densely strigose to pilose, deeply 2-lobed, lobes lanceolate to narrowly triangular, acute to acuminate.* *Inflorescences congested-cymose* *becoming lax with lateral axes elongating markedly, 4-8 × 8-20 cm with lateral axes to 8 cm, *sparsely to moderately pubescent with 2 types of pubescence, mixed strigillose to appressed puberulent and hirsute to villous, *pedunculate or sessile *and 3-partite; peduncles 1-3 cm; *bracts triangular or elliptic, 4-10 mm, usually 2- to multifid, acute to acuminate; *pedicels 1-6 mm. Flowers pedicellate, biology not noted. Calyx with hypanthium portion ellipsoid, 3-4 mm, strigose to sericeous; *lobes narrowly triangular to narrowly ligulate, 7-12 mm, hirsute, acute to acuminate, *with 1 lobe of 1-4 flowers per inflorescence sometimes expanded into calycophyll, blade elliptic-oblong to ovate, 6-8 × 2.5-5 cm, both surfaces glabrescent on lamina and strigillose on principal veins, base acute to cuneate, stipe 10-30 mm, apex acute or acuminate. *Corolla salverform, outside hirsute; tube 22-25 mm; lobes ovate, 6-7 mm, acuminate. Berry ovoid or ellipsoid, ca. 10 × 7 mm, strigose to glabrescent, *calyx limb deciduous. Fl. Apr-May. After going through the descriptions, I feel it may be *Mussaenda roxburghii* Hook.f. only. The following posts may also be of *Mussaenda roxburghii* Hook.f..: Mussaenda sp. for ID <https://groups.google.com/forum/#!topic/indiantreepix/PyVRNEpVc3o> Mussaenda frondosa? <https://groups.google.com/g/indiantreepix/c/3wHuOtgb-wA> Mussaenda glabrata (Hook.f.) Hutch. ex Gamble from Assam KD 02 Jul’ 2017 <https://groups.google.com/forum/#!topic/indiantreepix/RGEdgz4IpYY> MS July, 2017/06 Mussaenda sp. for Id <https://groups.google.com/forum/#!topic/indiantreepix/cz3kw_lgEqk> MS, June,2021/20 Mussaenda sp. for id. <https://groups.google.com/g/indiantreepix/c/Djx0yAK3a2Y> On Sat, 13 Aug 2022 at 09:51, Tabish <[email protected]> wrote: > To my eye, the sepals of Mussaenda frondosa > <https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:756632-1> > look broader in comparison to my images, and also more hairiness of the > plant. Also the buds of my plant look different from those of M. frondosa. > The buds of my plant appear to agree with the M. roxburghii images on Flora > of Bhutan site > https://biodiversity.bt/species/show/6298 > https://biodiversity.bt/group/royal_manas_national_park/ > observation/show/5360 > Tabish > > > On Friday, August 12, 2022 at 10:40:59 PM UTC+5:30 Tabish wrote: > >> Found this plant growing by riverside in Pasighat, Arunachal Pradesh in >> May end. >> I think this is Mussaenda roxburghii. Looking for confirmation or >> otherwise id suggestions. >> Best wishes >> Tabish >> > -- > You received this message because you are subscribed to the Google Groups > "eFloraofIndia" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web, visit > https://groups.google.com/d/msgid/indiantreepix/e2712789-7494-4034-9cdb-c942aacaf0f4n%40googlegroups.com > <https://groups.google.com/d/msgid/indiantreepix/e2712789-7494-4034-9cdb-c942aacaf0f4n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- With regards, J.M.Garg -- You received this message because you are subscribed to the Google Groups "eFloraofIndia" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/indiantreepix/CA%2BiuSFDOAREbHNV9t%3DYgamJPtDnww4TqSrE8kAq6P1jra7yhxQ%40mail.gmail.com.
