Shrub 3-10 ft tall. Bark brown, thin, branches and branchlets obtusely quadrangular, pubescent, nodes flattened. Leaves opposite, ovate-elliptic or sub-orbicular, 8-36 x 6-24 cm across, base acute, margin minutely dentate-serrate, apex acuminate, chartaceous, glabrous above and slightly pubescent beneath, lateral veins 6-9 on either side of the midrib, veins impressed above and distinct beneath, densely pubescent on the veins, petiole 1-20 cm long, exstipulate. Inflorescence terminal pyramidal thyrsoid panicle or corymb, compact about 10 cm wide, subsessile or on stout peduncles, bracts lanceolate, Flowers bisexual, zygomorphic, scarlet red, pedicel slender, about 1-2 cm long, calyx campanulate 5 toothed, teeth divided, leaf like, lanceolate, apex acuminate, accrescent in fruit, corolla hypocrateriform, subactinomorphic, 5 unequal lobed, scarlet red, lobes obovate, corolla tube narrow, glabrous, about 3-4 cm long, stamens 4, didynamous, exserted, filaments filiform, red, anthers oblong, bilobed, reddish brown, ovary bicarpellary, 4 lobed, 4 loculed, style filiform about the same length as the stamens, red, stigma shortly 2-fid, Fruit drupaceous globose, red, about 8 mm in diameter.
It is the favorite of butterflies.
Your posted 1st image looks different from those at Clerodendrum chinense in efi site.
Clerodendrum lasiocephalum C.B.Clarke, Fl. Brit. India [J. D. Hooker] 4(12): 594 (1885).
Clerodendrum lasiocephalum C.B.Clarke & C.E.C.Fisch., Bull. Misc. Inform. Kew 1940(7): 299, descr. ampl. (1941).
Plant identification : Sir, Please identify this cultivated flower, from a private house, Dimapur (Nagaland)
I could find three specimens of Clerodendrum lasiocephalum C.B.Clarke in GBIF.