Acanthoparyphinae

Pandaspinapyga tumida, from here.

Belongs within: Sphaerexochinae.
Contains: Nieszkowskia, Hyrokybe.

The Acanthoparyphinae is a lineage of epifaunal benthic trilobites known from warm-water palaeozooprovinces of Eurasia and North America in the Lower Ordovician to Upper Silurian. Members of the Acanthoparyphinae are characterised by a mature pygidium bearing two pairs of pleural spines, produced via the ontogenetic fusion of the ancestral four pairs (Přibyl et al. 1985).

<==Acanthoparyphinae
    |--+--Nieszkowskia PVP85
    |  |--Hammannopyge Přibyl & Vaněk in Přibyl, Vaněk & Pek 1985 PVP85
    |  |    `--*H. unica (Thomson 1857) [=Acidaspis unica] PVP85
    |  `--Holia Bradley 1930 PVP85
    |       |  i. s.: H. cimelia Whittington & Evitt 1954 PVP85
    |       |         H. sarykolica (Lisogor 1965) PVP85
    |       |         H. yakowlevi (Weber 1948) PVP85
    |       |--*H. magnospinosa Bradley 1930 PVP85
    |       `--+--H. anacantha Ludvigsen 1979 PVP85
    |          `--H. secristi Whittington & Evitt 1954 PVP85
    `--+--Pandaspinapyga Esker & Levin 1964 PVP85
       |    |--*P. projecta (Esker 1961) PVP85
       |    |--P. dactyla Chatterton & Ludvigsen 1976 PVP85
       |    |--P. furcillata (Ancygin 1973) PVP85
       |    |--P. gibba (Angelin 1854) PVP85
       |    |--P. mutica (Schmidt 1881) PVP85
       |    |--P. salsa Esker 1964 PVP85
       |    |--P. stubblefieldi (Bancroft 1949) PVP85
       |    |--P. tuberculata (Warburg 1925) PVP85
       |    `--P. tumida (Angelin 1854) PVP85
       `--+--Acanthoparypha Whittington & Evitt 1954 PVP85
          |    |--*A. perforata Whittington & Evitt 1954 PVP85
          |    |--A. chiropyga Whittington & Evitt 1954 PVP85
          |    |--A. echinoderma Chatterton & Ludvigsen 1976 PVP85
          |    |--A. evitti Chatterton & Ludvigsen 1976 PVP85
          |    |--A. goniopyga Ludvigsen 1979 PVP85
          |    |--A. subcircularis (Bradley 1930) PVP85
          |    `--A. trentonensis (Clarke 1897) PVP85
          `--+--Hyrokybe PVP85
             |--Shiqiania Chang 1974 PVP85
             |    |--*S. gaotanensis Chang 1974 PVP85
             |    `--S. punctata Chang 1974 PVP85
             `--Youngia Lindström 1885 PVP85
                  |--*Y. trispinosa (Young 1868) PVP85
                  |--Y. boucoti Chatterton & Perry 1984 PVP85
                  |--Y. brennardi Chatterton & Perry 1984 PVP85
                  |--Y. clintoni (Foerste 1894) PVP85
                  |--Y. folinsbesi Chatterton & Perry 1984 PVP85
                  |--Y. johnsoni Chatterton & Perry 1984 PVP85
                  |--Y. kathyae Chatterton & Perry 1984 PVP85
                  |--Y. luorepingensis (Wu 1977) PVP85
                  |--Y. moroides (Marret Nicholson 1888) PVP85
                  |--Y. steineri Chatterton & Perry 1984 PVP85
                  |--Y. tuberculata Dean 1971 PVP85
                  `--Y. walli Chatterton & Perry 1984 PVP85

*Type species of generic name indicated

REFERENCES

[PVP85] Přibyl, A., J. Vaněk & I. Pek. 1985. Phylogeny and taxonomy of family Cheiruridae (Trilobita). Acta Universitatis Palackianae Olomucensis Facultas Rerum Naturalium Geographica-Geologica XXIV 83: 107–193.