Altica (New Latin from Greek ἁλτικός , "haltikós", "jumper" or "jumping") is a large genus of flea beetles in the subfamily Galerucinae, with about 300 species, distributed nearly worldwide.
 The genus is best represented in the Neotropic region, well represented in the Nearctic and Palearctic, but occurs also in the Afrotropic, Indomalaya and Australasia.
 The species are similar to each other, small metallic blue-green-bronze beetles, often distinguished from each other only by the aedeagus.
 The species of "Altica", both as larvae and as adults, are phytophagous, feeding on plant foliage of various food plant taxa, specific for each "Altica" species.
 Onagraceae and Rosaceae (mainly "Rubus") are the dominant host plant families for Holarctic species.
 The adult "Altica" beetles are able to jump away when approached.
Cladosporium is a genus of fungi including some of the most common indoor and outdoor molds. Species produce olive-green to brown or black colonies, and have dark-pigmented conidia that are formed in simple or branching chains.
 Many species of "Cladosporium" are commonly found on living and dead plant material.
 Some species are plant pathogens, others parasitize other fungi.
 "Cladosporium" spores are wind-dispersed and they are often extremely abundant in outdoor air.
 Indoors "Cladosporium" species may grow on surfaces when moisture is present. "
Cladosporium fulvum", cause of tomato leaf mould, has been an important genetic model, in that the genetics of host resistance are understood.
 In the 1960s, it was estimated that the genus "Cladosporium" contained around 500 plant-pathogenic and saprotrophic species, but this number has since been increased to over 772 species.
 The genus "Cladosporium" is closely related to black yeasts in the order Dothideales.
 "Cladosporium" species are often highly osmotolerant, growing easily on media containing 10% glucose or 12–17% NaCl.
 They are rarely grown on media containing 24% NaCl or 50% glucose and never isolated from medium with 32% NaCl or greater.
 Most species have very fragile spore chains, making it extremely difficult to prepare a mount for microscopic observation in which the conidial chains are preserved intact.
Otiorhynchus (often spelt "Otiorrhynchus") is a large genus of weevils in the family Curculionidae.
 Many species of the genus, particularly the black vine weevil ("O. sulcatus") and the strawberry root weevil ("O. ovatus"), are important pests, both as larvae and as adults.
 Larvae feed on plant roots.
 Adults are flightless with fused elytra and feed at night on plant foliage.
 In many species of the genus at least some races are polyploid and parthenogenetic, while the rest of the races and species are diploid and bisexual.
 "Otiorhynchus" weevils, particularly "O. scaber", have been a popular subject for studies of the evolution of parthenogenesis.
 The genus is native to the Palearctic region.
 However, sixteen species were inadvertently introduced to North America and have become widespread there.
Weigela is a genus of between six and 38 species of deciduous shrubs in the family Caprifoliaceae, growing to 1–5 m (3-15') tall.
 All are natives of eastern Asia.
 The genus is named after the German scientist Christian Ehrenfried Weigel.
Philcoxia is a genus of four rare plant species in the Plantaginaceae that are endemic to Brazil and resemble terrestrial species of the genus "Utricularia".
 The genus, formally described in 2000, consists of the species "P. bahiensis", "P. goiasensis", "P. minensis", and "P. tuberosa", each of the first three named for the Brazilian state to which it is endemic.
 The species are characterized by subterranean stems, peltate leaves at or below the soil surface, and five-lobed calyces.
 Their habitat has been reported as areas of white sand in the midst of cerrado vegetation at an elevation between 800 and 1450 m. Initial descriptions of the genus included suspicions that the plethora of stalked capitate glands on the upper surfaces of leaves was an indication that these species may be carnivorous.
 A study published in 2007 tested "P. minensis" for protease activity, a typical test for the carnivorous syndrome, and could detect none.
 Later studies detected other digestive enzymes such as phosphatases and qualitatively assessed prey digestion and nutrient uptake, suggesting that it is a true carnivorous plant.
 The genus epithet honors David Philcox, a botanist at Kew Gardens who worked extensively in tropical Scrophulariaceae.
Martynia is a monotypic genus in the Martyniaceae consisting of a single species, Martynia annua, commonly known as the cat's claw, and is endemic to Mexico.
 It is a popular material for basket making among Native American tribes in the Southwest.
 The genus and species were first validly described by Carl Linnaeus in his 1753 publication "Species Plantarum".
 It was first collected, however, by the Scottish naval surgeon William Houstoun near Veracruz, Mexico.
 Houstoun sent seeds of this new plant to Philip Miller, chief gardener at the Chelsea Physic Garden, in 1731.
 Houstoun took the opportunity to name the plant "Martynia" in honor of a professor of botany at Cambridge, John Martyn.
 The plant was first seen in print in Martyn's famous work "Historia Plantarum Rariorum", with a full description and illustration.
 In this pre-Linnaean nomenclature era, Martyn gave the species the following descriptive name: "Martynia annua villosa et viscosa, folio subrotundo, flore magno rubro".
Melasphaerula is a genus of flowering plants in the family Iridaceae, first described as a genus in 1803.
 There is only one known species, Melasphaerula graminea, native to Namibia and the Cape Province in South Africa.
Lophodermium is a genus of fungi within the family Rhytismataceae.
 The genus contains 145 species and has a global distribution.
 Species of this genus are usually observed producing zone lines, conidiomata and ascomata on dead fallen leaves, but at least some are known to colonize living leaves.
 In many cases they then live inside the colonized leaf as a symptomless endobiont, where they are regarded as detritivores utilising dead plant matter.
 In a few cases they may kill all or part of the leaf prematurely, and there is a substantial literature dealing with those species as plant pathogens.
 The genus infects many different plant families but with a notable concentration in the family Pinaceae; many "Lophodermium" species are restricted to a single host genus (or even species), but some, particularly those infecting grasses, may infect several genera.
 Some are economically important plant pathogens, such as those that cause needlecast disease in European Black Pine, Scots Pine and Red Pine in forestry and christmas tree plantations.
 In these species, notably "L. pinastri" and "L. seditiosum", the fungal spores disperse and infect the pine needles in late summer, which turn brown by the following spring and then fall off.
Closterovirus, also known as beet yellows viral group, is a genus of viruses, in the family Closteroviridae.
 Plants serve as natural hosts.
 There are currently 11 species in this genus.
 Diseases associated with this genus include: yellowing and necrosis, particularly affecting the phloem.
 This genus has a probably worldwide distribution and includes among other viral species the "Beet yellows virus" (the type species) and "Citrus tristeza virus", rather economically important plant diseases.
 At least some species require vectors such as aphids or mealybugs for their transmission from plant to plant.
A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place".
 Examples commonly are plants unwanted in human-controlled settings, such as farm fields, gardens, lawns, and parks. Taxonomically, the term "weed" has no botanical significance, because a plant that is a weed in one context is "not" a weed when growing in a situation where it "is" in fact wanted, and where one species of plant is a valuable crop plant, another species in the same genus might be a serious weed, such as a wild bramble growing among cultivated loganberries.
 Many plants that people widely regard as weeds also are intentionally grown in gardens and other cultivated settings, in which case they are sometimes called beneficial weeds.
 The term "weed" also is applied to any plant that grows or reproduces aggressively, or is invasive outside its native habitat.
 More broadly "weed" occasionally is applied pejoratively to species outside the plant kingdom, species that can survive in diverse environments and reproduce quickly; in this sense it has even been applied to humans.

Question: Which genus of plant has more species, Melasphaerula or Weigela?
Answer: Weigela is a genus of between six and 38 species