Harvestmen (Opiliones) are an order of arachnids often confused with spiders, though the two orders are not closely related. Research on harvestman phylogeny (that is, the phylogenetic tree) is in a state of flux. While some families are clearly monophyletic, that is share a common ancestor, others are not, and the relationships between families are often not well understood. Position in Arachnida The relationship of harvestmen with other arachnid orders is still not sufficiently resolved. Up until the 1980s they were thought to be closely related to mites (Acari). In 1990, Shultz proposed grouping them with scorpions, pseudoscorpions and Solifugae ("camel spiders"); he named this clade Dromopoda. This view is currently widely accepted. However, the relationships of the orders within Dromopoda are not yet sufficiently resolved. Analyses of recent taxa suggested the harvestmen to be the sister group of the three others, collectively called Novogenuata. An analysis also considering fossile taxa concluded that the harvestmen are sister to Haplocnemata (Pseudoscorpions and Solifugae), with Scorpions being the sister group of those three combined. Recent analyses have also recovered the Opiliones as sister-group to the extinct Phalangiotarbids, although this has low support, or as sister group to a pseudoscorpion and scorpion clade. Relationship of suborders In 1796, Pierre André Latreille erected the family "Phalangida" for the then known harvestmen, but included the genus Galeodes (Solifugae). Tord Tamerlan Teodor Thorell (1892) recognized the suborders Palpatores, Laniatores, Cyphophthalmi (called Anepignathi), but also included the Ricinulei as a harvestman suborder. The latter were removed from the Opiliones by Hansen and William Sørensen (1904), rendering the harvestmen monophyletic. According to more recent theories, Cyphophthalmi, the most basal suborder, are a sister group to all other harvestmen, which are according to this system called Phalangida. The Phalangida consist of three suborders, the Eupnoi, Dyspnoi and Laniatores. While these three are each monophyletic, it is not clear how exactly they are related. In 2002, Giribet et al. came to the conclusion that Dyspnoi and Laniatores are sister groups, and called them Dyspnolaniatores, which are sister to Eupnoi. This is in contrast to the classical hypothesis that Dyspnoi and Eupnoi form a clade called Palpatores. Dyspnolaniatores was also recovered in a 2011 study. In 2014, new analysis by Garwood et al. examined 158 morphological traits across 272 species. In Garwood's phylogenetic tree, the basal Opiliones split into the Phalangida and stem Cyphophthalmi. The Cyphophthalmi stem then diversified into Cyphophthalmi