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More than 150 MAX phases are known to date. Their chemical diversity is the result of mixing-and-matching early-to-mid transition metals (M), main group elements (A), and carbon and/or nitrogen (X). The vast majority of the respective carbides and (carbo)nitrides contain group 13 and 14 as the A element, such as Al, Ga, and Si. V2PC is among the least studied members of this family of materials; as a matter of fact, it is only mentioned in two pieces of original literature. The solid-state synthesis is extremely vaguely described and working with elemental phosphorus poses additional synthetic challenges. Here, we confirm these experimental difficulties and present an alternative sol gel-based approach to prepare almost single-phase V2PC. The versatility of the sol gel chemistry is further demonstrated by variation of the gel-building agent moving beyond citric acid as the carbon source. DFT calculations support the experimentally obtained structural parameters and show V2PC is a metal.

Gynodioecy, a state where female and hermaphrodite plants coexist in populations, has been widely proposed an intermediate stage in the evolutionary pathway from hermaphroditism to dioecy. In the gynodioecy-dioecy pathway, hermaphrodites may gain most of their fitness through male function once females invade populations. To test this prediction, comprehensive studies on sex ratio variation across populations and reproductive characteristics of hermaphrodite and female phenotypes are necessary. This study examined the variation in sex ratio, sex expression, flower and fruit production and sexual dimorphism of morphological traits in a gynodioecious shrub, Daphne jezoensis, over multiple populations and years. Population sex ratio (hermaphrodite:female) was close to 1:1 or slightly hermaphrodite-biased. Sex type of individual plants was largely fixed, but 15% of plants changed their sex during a 6-year census. Hermaphrodite plants produced larger flowers and invested 2.5 times more resources in flower production than female plants, but they exhibited remarkably low fruit set (proportion of flowers setting fruits). Female plants produced six times more fruits than hermaphrodite plants. Low fruiting ability of hermaphrodite plants was retained even when hand-pollination was performed. Fruit production of female plants was restricted by pollen limitation under natural conditions, irrespective of high potential fecundity, and this minimised the difference in resources allocated to reproduction between the sexes. Negative effects of previous flower and fruit production on current reproduction were not apparent in both sexes. This study suggests that gynodioecy in this species is functionally close to a dioecious mating system: smaller flower production with larger fruiting ability in female plants, and larger flower production with little fruiting ability in hermaphrodite plants.

• Since the time of Charles Darwin, the variation in floral characteristics and its effects on plant mating system evolution have fascinated scientists. Recent advances in the field of genetics, molecular biology, and ecology have been very effective in addressing questions regarding mechanisms and interactions underlying the evolution of plant mating systems using various model and nonmodel species. The depth of plant mating system research reflects the complexity and diversity seen in nature, ranging from self-compatible hermaphroditic flowers to separate sexed individuals. Further, the mechanisms involved in the evolution of plant mating systems are much more diverse and differ even among closely related species. Here, as a special section, we present a suite of original papers that range from theoretical modeling to multiyear field research that address different factors affecting plant mating systems, and their effects on shaping interactions between plants, insects, and their environment.