Bayer & Kubitzki, Inflorescence morphology of Lasiopetaleae (Sterculiaceae) 
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ir\ any species, but axillary shoots which start flowering without producing extensive 
vegetative zones may give the impression of axillary inflorescences. 
The inflorescences of the Lasiopetaleae are structurally not homogeneous. In 
Keraudrenia lieniianniifolia (Fig. 1) the inflorescence comprises a terminal flower (1) 
and two lateral, cymose partial inflorescences. In comparison with other Lasiopetaleae 
studied, this represents the most complete ramification pattern. In early 
developmental stages the main inflorescence axis bears three bracts, which during 
the development of the inflorescence change their original positions. One of these 
bracts is shifted upward on the main axis beyond the nodes from which the lateral 
cymes branch off; the axil of this bract remains empty (a). The two other bracts, 
which subtend cymose partial inflorescences, are displaced beyond the prophyllar 
nodes of their axillary products (b, c). These displacements (metatopies) to a more 
distal position on the axis can be specified as recaulescence sensu Troll (1964). 
The inflorescences of all other Lasiopetaleae investigated (Thomasia, Hannafordia, 
Guiclienotia, Lysioscpaltim) are terminal monochasia with more or less pronounced 
metatopies between subtending bracts and their axillary flowers (Fig. 3). Beneath 
each flower an epicalyx of three bract-like appendages is usually found, which 
encloses the flower in bud. In few-flowered inflorescences like those of Thomasia 
discolor (Fig. 3 A), the sympodial character can easily be detected. The first flower to 
open (1) is the only one devoid of a subtending bract. This indicates that it is the 
terminal flower of the whole inflorescence. The subtending bract of the second flower 
(2) can not be traced at the branching point between the stalk of the terminal flower 
and the rest of the inflorescence. It is situated further distally (arrow), so that a 
recaulescent displacement has to be stated again. Accordingly, the subtending bract 
of the next flower (3) is displaced as well. If this type of ramification is repeated 
several times, many-flowered monochasia will result (e.g. Thomasia quercifolia, Fig. 2, 
and T. solanacea, T. rhynchocarpa). Other species (T. discolor, Fig. 3 A, T. sarotes, 
T. petalocalyx, T.foliosa) and representatives of other genera (Hannafordia, Guiclienotia, 
Lysiosepalum: Fig. 3 B) exhibit the same basic type of inflorescence ramification. 
Discussion 
In most Lasiopetaleae investigated, the inflorescence is clearly terminal. The leaf- 
opposed position of the inflorescences is a consequence of the sympodial shoot 
structure. If the stipules resemble foliage leaves, the wrong impression of an 
'inflorescentia intrafoliacea' (Gay 1821) may result. The additional bud in the axil of 
the foliage leaf, which subtends the subsequent module (Fig. 2 B), is interpreted as 
a serial accessory bud. However, it cannot be excluded that it originated from a 
displaced and reduced basal ramification from a prophyllar axil of the subsequent 
module. Axillary inflorescences have not been observed. Therefore indications in the 
taxonomic literature referring to axillary inflorescences are likely to be based on 
misinterpretations of the sympodial shoot structure. Nevertheless, the existence of 
short axillary shoots provided with a terminal inflorescence cannot be excluded. In 
such cases, however, the recognition of an axillary inflorescence would only depend 
on the extension of the proximal vegetative zone of the side branch. 
In contrast to the descriptions in part of the taxonomic literature, not a single member 
of the Lasiopetaleae investigated exhibits racemes. Some inflorescences (e.g. in Thomasia) 
superficially resemble racemes but in fact are cincinni. There are cases in which the 
distinction between monopodia and monochasia is not obvious, but two characteristics 
provide arguments in favour of the latter interpretation: at least during early 
developmental stages, the flowers are oriented towards one side of the inflorescence. 
