Illustrative key for Abutilon spp. in the Maltese Islands - by Stephen Mifsud.
Vers V3.80

Abutilon
Mill.
Indian Mallows    Ħobbejz isfar
Taxa left beyond this couplet: 2
Abutilon grandifolium
Abutilon theophrasti
Description of Abutilon
Abutilon is a genus of herbs, shrubs, or small trees characterized by soft pubescence and alternate, simple leaves that are often cordate, ovate, or palmately veined. The flowers are usually solitary or arranged in small clusters in the leaf axils, with five distinct petals, commonly yellow, orange, pink, or red. Epicalyx absent unlike several genera of this family. The calyx is persistent and five-lobed. Stamens numerous, united into a staminal column surrounding the style, often grouped and capitate. The fruit is a schizocarp composed of several one-seeded mericarps, arranged in a ring around a central axis.
Description by D. A. Webb extracted from Flora Europaea Vol 1-5 (Tutin et al., 1964-1993)
Abutilon key: couplet steps >> 1
 
Lead

1.A

+
No of mericarps (fruiting compartments) > 12
ref
++
Hairs short ( < 2mm) with a gland at the tip
ref
+++
Mature plants 30–80 cm high
ref
OR
 
Lead

1.B

-
No of mericarps ( fruiting compartments) 6-12
ref
- -
Hair simple, villous, eglandular > 2 mm long
ref
- - -
Mature plant 100–300 cm high
ref

[A]     Illustration of Lead 1.A + [B]     Illustration of Lead 1.B - Identification Tips  
It is recommended to average measurements from three to five well-developed fruit heads to avoid artificially low or high values.
Image of A. theophrasti by Stephen Mifsud Image of A. grandifolium by Stephen Mifsud