Legless lizards of the genus Anniella are found only in western North America, roughly from the San Francisco Bay area south to northwestern Baja California, Mexico. These lizards are found burrowing in sandy soils, often in dunes and typically no more than 100km or so away from the coast, where native shrubs create enough leaf litter to retain moisture and lower temperatures in the sandy substrate. The plants also support an insect fauna presumably used as food by the lizards. While most lizards do best with higher temperatures, Anniella seem to prefer lower temperatures at which they remain active both under and above ground, where they are sometimes spotted on cooler days.

The lineage to which these lizards belongs has had more or less the same restricted geography since the Miocene and, until recently, was thought to consist of one "widespread" species and a second far more restricted one. A pulchra essentially was presumed to have, until recently, essentially the same range as the genus. The only other named species is A geronimensis, described in 1940 for a distinct population in northwestern Baja and partially overlapping that of A pulchra.

Theodore J Papenfuss of UC Berkeley and James F Parham of Cal State Fullerton have reshaped our understanding of this fascinating genus. A. pulchra is not so widespread as believed and the genus is more species rich than suspected. The authors conducted the most data-intensive comparative study to date, sampling populations at 45 localities spanning the full range of the genus. Using mitochondrial and nuclear DNA sequences, they found populations of "A pulchra" that differed by 4.3 to 9.2%, gaps typical of differences between other lizard species. Suspecting that there was more than one species masquerading under the A pulchra name, they correlated these impressive genetic distances with several morphological features including colouration, vertebral numbers, scale patterns, and karyotype profiles. As a result, they named four species new to science and concluded that A pulchra is not nearly so common as previously thought.

Anniella species, like other fossorial lizards with limbs reduced or absent, are described as "morphologically conservative." This may sound bizarre for lineages that have transformed from having four fully formed legs to appearing wormlike. What could be more radical? Yet, in spite of widely distributed populations and the obviously limited ability of individual animals to move between them, little morphological variation is seen within these species. Genetically one would expect divergence among at least the more isolated populations, so in spite of anatomically conserved appearances, there are increasing examples of previously undetected, yet evolutionarily distinct, cryptic species. This has now been shown to be the case with Anniella. Cryptic species are a well-known phenomenon, such as bird or cricket species first detected by differences in their songs. Such cases generally conclude with confirmation by overlooked or misinterpreted morphological details or by DNA data. In the end, it is a question of gathering enough data within and among populations to distinguish between species and genetic variation.

The new species A grinnelli differs from all the others in its greyish-red ventral colour that is continuous from the tip of the lower jaw to the tip of the tail. The type locality for the species is Sand Ridge Preserve in the southern San Joaquin valley of California, to the east side of the Carrizo plain. What might be encouraging news for the species is that three populations were discovered within the city limits of Bakersfield. Tragically, two of the three were destroyed in the last 10 years by housing development.

This species was named for the 19th-century American naturalist Joseph Grinnell, 1877-1939, who served as the first director of UC Berkeley's Museum of Vertebrate Zoology and who published hundreds of papers and conceived the "Grinnell method" for taking field notes that became a standard for natural history observations.

I have not had to good fortune to personally see very many legless lizards in the wild, and not only because I am preoccupied looking for beetles. So I was curious about how the authors went about collecting so many specimens from so many localities. They used a clever, if low-tech, method described as "cover objects". Basically, folded cardboard boxes and scraps of plywood were lain on sandy soils and periodically lifted to check for lizards.