Question: What type of category does Cassiope and Pediocactus have in common?

Context articles: Fitkid
Pediocactus peeblesianus
Pediocactus knowltonii
Ericaceae
Cassiope tetragona
Cassiope
Pediocactus
Pediocactus bradyi
Pediocactus sileri
Pediocactus despainii

Fitkid (also "FitKid", "Fit Kid" or "Fit-Kid") is a type of children's sport combining gymnastics, dance and acrobatics.
 It originated in Europe in the 1990s, and is meant to engage children 8–18 years of age in fun individual and group exercise, free of the extremes of more strenuous aerobics or traditional gymnastics.
 International competitions are organized regularly by the "International FitKid Division", in addition to national competitions.
 A routine stands of four types of elements: strength, flexibility, acrobatics, and jumps.
 All elements are graded by difficulty from A to H.
 A elements being worth 0.1 points, B 0.2, C 0.3, and so on until H which is worth 0.8.
 Routines get evaluated in three categories: technique, artistry, and content (execution of elements).
 Competition is divided by age groups (I. to IX.
 (or Senior in A category)), and categories ( which are based on knowledge).
 There three categories (from hardest to easiest) A, B, and C, also called Dance.
 In each categories there are group and individual routines.
 In C Category (here group routines are also called Dance Show) team member can go from 4 to 8.
 In A and B category there are duos, small groups (3-4), and big groups (5-6).
 In C category, individually 4 elements have to be performed ( one from each type), A or B difficulty, and in groups, two are optional.
 In B category individually 8 elements need to be performed ( two from each type) A-D difficulty ( but max.
 two elements can be D), and in groups 4 (same as C category individual).
 In A category team and individual, 8 elements need to be performed (same as B category) and an acrobatic connection is optional.
 Skills in A category can be any difficulty.
Pediocactus peeblesianus is a rare species of cactus known by the common names Navajo pincushion cactus.
 It is endemic to the state of Arizona in the United States.
 One subspecies of the plant is federally listed as an endangered species of the U.S.
Pediocactus knowltonii is a rare species of cactus known by the common names Knowlton's miniature cactus, Knowlton's pincushion cactus, and Knowlton's minute cactus.
 It is endemic to San Juan County, New Mexico, in the United States.
 It is the smallest and rarest species in genus "Pediocactus".
 It is threatened by a number of human activities.
 It is federally listed as an endangered species of the United States.
The Ericaceae are a family of flowering plants, commonly known as the heath or heather family, found most commonly in acid and infertile growing conditions.
 The family is large, with c. 4250 known species spread across 124 genera, making it the 14th most species-rich family of flowering plants.
 The many well-known and economically important members of the Ericaceae include the cranberry, blueberry, huckleberry, rhododendron (including azaleas), and various common heaths and heathers ("Erica", "Cassiope", "Daboecia", and "Calluna" for example).
Cassiope tetragona (common names include Arctic bell-heather, white Arctic mountain heather and Arctic white heather) is a plant native to the high Arctic and northern Norway, where it is found widely.
Cassiope is a genus of 9-12 small shrubby species in the family Ericaceae.
 They are native to the Arctic and north temperate montane regions.
 The genus is named after Cassiopeia of Greek mythology.
 Common names, shared with several other similar related genera, include heather and heath.
 They have scale-like leaves lying against the stems, and produce solitary bell-shaped flowers in late spring.
 Though hardy, flowers can be damaged by late frosts.
Pediocactus (Greek: πεδίον (pedion) means "plain", "flat", "field") is a genus of cacti.
 The genus comprises between 6 and 11 species, depending upon the authority.
 Species of this genus are referred to as hedgehog cacti, though that name is also applied to plants from the genera "Echinocereus" and "Echinopsis".
 Species may also be referred to as pincushion cacti, a common name which is also applied to other genera.
Pediocactus bradyi is a rare species of cactus known by the common names Brady's pincushion cactus, Brady's hedgehog cactus, and Marble Canyon cactus.
 It is endemic to Arizona in the USA, where it is restricted to Marble Canyon in Coconino County.
 It is limited to a specific type of soil, it has a small distribution, and the species is threatened by a number of human activities.
 This has been a federally listed endangered species of the United States since 1979.
Pediocactus sileri is a rare species of cactus known by the common names Siler's pincushion cactus and gypsum cactus (or gypsum plains cactus).
 It is native to southwestern Utah and northwestern Arizona in the United States.
 It is limited to a specific type of soil, individuals are often spaced far apart, and the species is threatened by a number of human activities such as off-road vehicle use, poaching, and uranium mining.
 This is a federally listed threatened species of the United States.
Pediocactus despainii is a rare species of cactus known by the common names Despain's cactus and San Rafael cactus.
 It is endemic to the state of Utah in the United States, where it is limited to the San Rafael Swell in Emery County, Utah.