Question: Which genus has more known species, Eucommia or Rhoicissus?

full_context: Document 1: Eucommia montana: Eucommia montana is an extinct species of flowering plant in the family Eucommiaceae. "E. montana" is known from fossil fruits found in Eocene deposits of the northwestern United States southeastern British Columbia south to Oregon and east to Montana and Colorado. "E. montana" is one of five described fossil species from North America assigned to the modern genus "Eucommia". The other species are "E. constans", "E. eocenica", "E. jeffersonensis", and "E. rowlandii".
Document 2: Rhoicissus: Rhoicissus is an Afrotropical plant genus in the grape family Vitaceae and Vitoideae subfamily. There are between 9 and 22 accepted species.
Document 3: Cissus: Cissus is a genus of approximately 350 species of lianas (woody vines) in the grape family (Vitaceae). They have a cosmopolitan distribution, though the majority are to be found in the tropics.
Document 4: Ulmus parvifolia: Ulmus parvifolia, commonly known as the Chinese elm or lacebark elm, is a species native to eastern Asia, including China, India, Taiwan, Japan, North Korea, and Vietnam. It has been described as "one of the most splendid elms, having the poise of a graceful "Nothofagus"".
Document 5: Vitaceae: The Vitaceae are a family of dicotyledonous flowering plants, with 14 genera and ca 910 known species, including the grapevine and Virginia creeper. The family name is derived from the genus "Vitis". The name sometimes appears as Vitidaceae, but Vitaceae is a conserved name and therefore has priority over both Vitidaceae and another name sometimes found in the older literature, Ampelidaceae. In the APG III system (2009) onwards, the family is placed in its own order, Vitales. Molecular phylogenetic studies place the Vitales as the most basal clade in the rosids.
Document 6: Eucommia eocenica: Eucommia eocenica is an extinct species of flowering plant in the family Eucommiaceae. "E. eocenica" is known from fossil fruits found in the middle Eocene Claiborne Formation deposits of the southeastern United States. "E. eocenica" is one of five described fossil species from North America assigned to the modern genus "Eucommia". The other species are "E. constans", "E. jeffersonensis", "E. montana", and "E. rowlandii".
Document 7: Eucommia constans: Eucommia constans is an extinct species of flowering plant in the family Eucommiaceae. "Eucommia" is a genus of small trees now native to China, with a fossil record that shows a much wider distribution. "E. constans" is known from fossil fruits found in Miocene to Pleistocene deposits of east-central Mexico. "E. constans" is one of five described fossil species from North America assigned to the modern genus "Eucommia". The other species are "E. eocenica", "E. jeffersonensis", "E. montana", and "E. rowlandii".
Document 8: Eucommia: Eucommia is a genus of small trees now native to China, with a fossil record that shows a much wider distribution. The single living species, "Eucommia ulmoides", is near threatened in the wild, but is widely cultivated in China for its bark, and is highly valued in herbology such as traditional Chinese medicine.
Document 9: Ampelocissus africana: Ampelocissus africana is a type of vine that is woody, or liana of the grape family, bearing edible fruit. It is native to habitats in, and around forested areas in Guinea, Ivory Coast, Nigeria, Cameroon, Chad, Central African Republic, Sudan, Kenya, Rwanda, Burundi, Tanzania (including the Zanzibar Archipelago, from where the type specimen was collected), Malawi, Zambia, Mozambique, Zimbabwe and Botswana. It was originally described botanically in 1790 by João de Loureiro as "Botria africanus", which is the basionym for its treatment here under "Ampelocissus".
Document 10: Eucommia jeffersonensis: Eucommia jeffersonensis is an extinct species of flowering plant in the family Eucommiaceae. It is known from a fossil fruit found in latest Eocene deposits of Oregon, United States. "E. jeffersonensis" is one of five described fossil species from North America assigned to the modern genus "Eucommia". The other species are "E. constans", "E. eocenica", "E. montana", and "E. rolandii".
Document 11: Eucommia rolandii: Eucommia rolandii is an extinct species of flowering plant in the family Eucommiaceae. "E. jeffersonensis" is known from a fossil leaves found in Middle Eocene deposits of British Columbia, Canada and Mississippi, United States. "E. rolandii" is one of five described fossil species from North America assigned to the modern genus "Eucommia". The other species are "E. constans", "E. eocenica", "E. jeffersonensis", and "E. montana".
Document 12: Ruscus: Ruscus is a genus of six species of flowering plants, native to western and southern Europe (north to southern England), Macaronesia, northwest Africa, and southwestern Asia east to the Caucasus. In the APG III classification system, it is placed in the family Asparagaceae, subfamily Nolinoideae (formerly the family Ruscaceae). Like many lilioid monocots, it was formerly classified in the family Liliaceae.
Document 13: Rubus: Rubus is a large and diverse genus of flowering plants in the rose family, Rosaceae, subfamily Rosoideae, with 250–700 species.
Document 14: Streptocarpus rexii: Streptocarpus rexii is a South African plant in the "Gloxinia" and African Violet family of Gesneriaceae, and occurring widely from the southern Cape along the coastal hills, mountains, wooded ravines and valleys, and moist forests of the east coast, through Natal as far north as the Eastern Transvaal, up to an altitude of about 900 m. This genus of epiphytes and lithophytes, of about 130 species, is mainly African and Mascarene, with four vagrant species in Asia. "Streptocarpus", as do other Old World Gesneriaceae, is unusual in that it displays anisocotylous or unequal growth, i.e. one cotyledon continues to grow after germination.
Document 15: Ribes: Ribes is a genus of about 150 known species of flowering plants native throughout the temperate regions of the Northern Hemisphere. It is usually treated as the only genus in the family Grossulariaceae, but a few taxonomists place the gooseberry species in a separate genus of "Grossularia".
ground_truth: Rhoicissus