Sciuridae

Indian palm squirrel Funambulus palmarum, photographed by J. M. Garg.

Belongs within: Paramys.
Contains: Pteromyini, Sciurini, Callosciurini, Xerinae.

The Sciuridae are the squirrels, a family of rodents found on all continents except Australia and Antarctica. Ancestrally, squirrels are probably arboreal, but a number of lineages have become more terrestrial. Living squirrels have a sciuromorphous skull, with the attachment sites for the jaw muscles extending forward onto the rostrum, and teeth with well-developed lophs instead of individual cusps, but the Palaeogene Cedromurinae have a protrogomorphous skull with less extensive muscle attachments and bunodont teeth with distinct individual cusps (Wang & Qiu 2003).

See also: Squirrels and cedar-mice (Taxon of the Week: Sciuridae).

Characters (from Wang & Qiu 2003): Sciuromorphous skull (small infraorbital foramen, medial masseter starting from inner side of anterior end of zygoma without passing through infraorbital foramen, broad zygomatic plate, lateral masseter extending onto rostrum) (absent in Douglassciurus [Mercer & Roth 2003] and Cedromurinae); palate usually broad, terminating at level of or behind third molar; dental formula: 1.0.1-2.3/1.0.1.3; rooted cheek teeth, P⁴ molariform, P⁴—M³ with four transverse lophs, longitudinally extending protocone, without conules and hypocone.

Sciuridae
    |--Cedromus B74 [Cedromurinae WQ03]
    `--+--+--Sciurillus [Sciurillinae, Sciurillini] SSH04
       |  |    `--S. pusillus MR03
       |  |         |--S. p. pusillus MR03
       |  |         `--S. p. kuhlii MR03
       |  `--Ratufa [Ratufinae, Ratufini] SSH04
       |       |--R. affinis MR03
       |       |--R. bicolor (Sparrman 1778) K92
       |       |--R. indica IT07
       |       `--R. macroura IT07
       `--+--Sciurinae SSH04
          |    |--Pteromyini SSH04
          |    `--+--Sciurini SSH04
          |       `--Tamiasciurus [Tamiasciurini] SSH04
          |            |--T. douglasii IT07
          |            |--T. hudsonicus MR03
          |            |    |--T. h. hudsonicus B75
          |            |    `--T. h. minnesota (Allen 1899) [=Sciurus hudsonicus minnesota] B75
          |            `--T. mearnsi IT07
          `--+--Callosciurinae SSH04
             |    |--Callosciurini SSH04
             |    `--Funambulus MR03 [Funambulini SSH04]
             |         |--F. layardi IT07
             |         |--F. palmarum MR03
             |         |--F. pennanti MR03
             |         |--F. sublineatus IT07
             |         `--F. tristriatus IT07
             `--Xerinae SSH04

Sciuridae incertae sedis:
  Palaeosciurus MR03
  Vulcanisciurus africanus L78
  Douglassciurus jeffersoni [=Protosciurus jeffersoni] SSH04
  Aepyosciurus Wang & Qiu 2003 [Aepyosciurinae] WQ03
    `--*A. orientalis Wang & Qiu 2003 WQ03
  Baginia tenuis B49
    |--B. t. tenuis B49
    |--B. t. evidens B49
    `--B. t. lowii [=Sciurus lowii] B49
  Hesperopetes thoringtoni MJ11

*Type species of generic name indicated

REFERENCES

[B49] Baker, E. W. 1949. A review of the mites of the family Cheyletidae in the United States National Museum. Proceedings of the United States National Museum 99 (3238): 267-320.

[B75] Bowles, J. B. 1975. Distribution and biogeography of mammals of Iowa. Special Publications, The Museum, Texas Tech University 9: 1-184.

[B74] Bugge, J. 1974. The cephalic arterial system in insectivores, primates, rodents and lagomorphs, with special reference to the systematic classification. Acta Anatomica 87 (Suppl 62): 1-160.

[IT07] Isaac, N. J. B., S. T. Turvey, B. Collen, C. Waterman & J. E. M. Baillie. 2007. Mammals on the EDGE: conservation priorities based on threat and phylogeny. PloS One 2 (3): e296.

[K92] Klompen, J. S. H. 1992. Phylogenetic relationships in the mite family Sarcoptidae (Acari: Astigmata). Miscellaneous Publications, Museum of Zoology, University of Michigan 180: i-vi, 1-154.

[L78] Lavocat, L. 1978. Rodentia and Lagomorpha. In Evolution of African Mammals (V. J. Maglio & H. B. S. Cooke, eds) pp. 69-89. Harvard University Press: Cambridge (Massachusetts).

[MR03] Mercer, J. M., & V. L. Roth. 2003. The effects of Cenozoic global change on squirrel phylogeny. Science 299: 1568-1572.

[MJ11] Meredith, R. W., J. E. Janečka, J. Gatesy, O. A. Ryder, C. A. Fisher, E. C. Teeling, A. Goodbla, E. Eizirik, T. L. L. Simão, T. Stadler, D. L. Rabosky, R. L. Honeycutt, J. J. Flynn, C. M. Ingram, C. Steiner, T. L. Williams, T. J. Robinson, A. Burk-Herrick, M. Westerman, N. A. Ayoub, M. S. Springer & W. J. Murphy. 2011. Impacts of the Cretaceous terrestrial revolution and KPg extinction on mammal diversification. Science 334: 521-524.

[SSH04] Steppan, S. J., B. L. Storz & R. S. Hoffmann. 2004. Nuclear DNA phylogeny of the squirrels (Mammalia: Rodentia) and the evolution of arboreality from c-myc and RAG1. Molecular Phylogenetics and Evolution 30: 703-719.

[WQ03] Wang, B. Y., & Z. X. Qiu. 2003. Aepyosciurinae—a new subfamily of Sciuridae (Rodentia, Mammalia) from basal loess deposits at the northeastern border of Tibetan Plateau. Chinese Science Bulletin 48 (7): 691-695.