The new species Alyxoria sierramadrensis is described from Mexico where it inhabits limestone rocks. The lichen developing from this fungus is characterized by a placodioid to subfoliose thallus with a white pruinose surface; rounded to shortly elongated ascomata with a black epruinose margin and a widely exposed, white pruinose hymenial disc; hyaline, 3-septate ascospores, 17–25 × 7–9 μm; the presence of anthraquinones rendering the medulla orange. Phylogenetic analyses of nuLSU, mtSSU and RPB2 sequences place this species in the genus Alyxoria (Lecanographaceae). This generic affiliation is surprising because all known Alyxoria species have a crustose thallus. Lecanographaceae mainly includes species without a thallus (lichenicolous taxa) or with a thin crustose thallus, the only exception being Simonyella variegata with a fruticose thallus. The new species belongs to the Alyxoria ochrocheila subgroup, which includes lichens also frequently known to have anthraquinones, white pruinose hymenial discs and 3-septate ascospores. Phylogenetic analyses further determined the systematic position of the monotypic genus Phoebus. This genus, considered as an Arthoniales of uncertain family affiliation, is shown to belong to the Lecanographaceae. With its placodioid thallus, it is another example of a lichenized fungus with a deviating morphology in thallus structure for the family, increasing the number of remarkable cases of parallel evolution of lichen growth forms within the Arthoniales. Phoebus hydrophobius is newly recorded for Mexico.

中文翻译：

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Lecanographaceae (Arthoniales) 的 placodioid thallus 生长形式平行进化的显着案例与墨西哥 Alyxoria 新种的描述

新物种雪花梨来自墨西哥的描述，它栖息在石灰岩中。由这种真菌发育而来的地衣的特征是具有白色粉红色表面的近叶状菌体。圆形至短拉长的子囊，带有黑色的毛刺边缘和广泛暴露的白色毛刺状处女膜盘；透明的，3 分隔子囊孢子，17-25 × 7-9 μm；蒽醌的存在使髓质呈橙色。nuLSU、mtSSU 和RPB2序列将该物种归入该属亚力克索里亚(枸杞科）。这种通用从属关系令人惊讶，因为众所周知亚力克索里亚物种有壳状菌体。枸杞科主要包括没有菌体（地衣菌类群）或有薄壳状菌体的物种，唯一的例外是杂色西蒙尼氏菌带有果糖菌体。新物种属于赭色刺槐亚组，其中包括地衣也经常已知具有蒽醌、白色的处女膜盘和 3 分隔子囊孢子。系统发育分析进一步确定了单型属的系统位置菲比斯. 该属被认为是蒿目家庭关系不明的，被证明属于枸杞科. 凭借其 placodioid thallus，它是地衣真菌的另一个例子，该真菌在该家族的地衣结构中具有不同的形态，增加了地衣生长形式平行进化的显着案例的数量。蒿目.疏水火凤凰是为墨西哥新录制的。