Few studies have reported the venation pattern and micromorphology of Malveae schizocarpic fruits. These reproductive structures are present in Gaya and other genera of the tribe and may prove useful for solving taxonomic problems and understanding phylogenetic relationships within. We analyzed the mericarp and the seeds of 13 Brazilian species of Gaya and 11 species of related genera to provide useful comparative features for their taxonomy and phylogeny. The samples were subjected to the herborization reversal procedure and followed methods of scanning electron microscopy, light microscopy and diaphanization. The studied species of Gaya were compared on a binary matrix of characters analyzed through UPGMA. Within Gaya, the mericarp constriction corresponds to the dehiscence lines, which may occur at the basal portion or ventrally. Two to three veins in contact with the columella (central structure to which the mericarps are attached) were observed in this region. At the upper ventral margin, we observed only one vein connecting with the columella. The exocarp exhibited simple, biradiate, stellate and multiradiated trichomes. Capitate glandular trichomes were also observed. Species from related genera (Briquetia, Callianthe, Herissantia and Hochreutinera) showed stellate trichomes. Glandular and tector trichomes were observed in Gaya seeds, while other genera exhibited only simple trichomes. Venation pattern and micromorphological characters of mericarps, as well as novel seed trichome types here reported support of Gaya support the delimitation of genera studied and highlight the isolated position of Gaya within Malvaeae.

很少有研究报道锦葵属裂果的脉络模式和微形态。这些生殖结构存在于Gaya和部落的其他属中，可能有助于解决分类学问题和了解内部的系统发育关系。我们分析了 13 种巴西Gaya种和 11 种相关属的分果和种子，为它们的分类学和系统发育提供有用的比较特征。对样品进行除草逆转程序并遵循扫描电子显微镜、光学显微镜和透明化的方法。在通过 UPGMA 分析的二进制字符矩阵上比较了研究的Gaya物种。在加雅，分果收缩对应于开裂线，开裂线可能发生在基部或腹侧。在该区域观察到两到三个与小柱（分果附着的中央结构）接触的静脉。在上腹缘，我们只观察到一根静脉与小柱相连。外果皮表现出简单的、双辐射的、星状的和多辐射的毛状体。还观察到头状腺毛。来自相关属（Briquetia、Callianthe、Herissantia和Hochreutinera）的物种显示出星状毛状体。在加雅观察到腺毛和扇状毛种子，而其他属只表现出简单的毛状体。分果的脉络模式和微形态特征，以及这里报道的新型种子毛状体类型支持Gaya支持所研究的属的划分，并突出了Gaya在锦葵科中的孤立位置。