In comparing specimens of D. spatulata from southern Sinaloa (UMMZ 115322) with specimens of D. reticulata from Tehuantepec, Oaxaca (UMMZ 115321), the differences noted by Taylor (1942c:60) were found to be constant. But specimens from Ostula, Michoacán (UMMZ 104418), and five individuals from Colima (TNHC 26379-83) were found to be intermediate in certain characters. The skin of the dorsum in D. reticulata is granular; that in D. spatulata is smooth. The skin in specimens from Ostula and Colima is slightly granular. The dorsal ground color of D. reticulata is yellowish brown with dark reticulations; the dorsal ground color of D. spatulata is olive-green. Specimens from Ostula and Colima most closely resemble those from Tehuantepec in coloration, but the reticulations are more coarse, and the ground color has an olive-green tint. Diaglena reticulata also differs from D. spatulata in having a larger over-all size, slightly broader head, a narrower interorbital distance, and a more pointed snout with a deeper labial shelf (Table 4). The specimens from Ostula and Colima are intermediate between D. reticulata from Oaxaca and D. spatulata from Sinaloa in body proportions.
Of three specimens from the Tepalcatepec Valley (JRD 5991-3), only two are suitable for measuring. These specimens are smaller than adults from the coastal areas and have broader heads and snouts, but narrower interorbital distances, than specimens in the other samples (Table 4). The texture of the skin is like that of specimens from Ostula and Colima. The coloration resembles that of D. reticulata, but the reticulations are bold and form indistinct bands on the hind limbs.
Table 4.—Comparison of Four Characters in Five Samples of Diaglena.
(All Data Are for Males; Means Given in Parentheses Below Ranges.)
| Locality | Number of specimens | Snout-vent length | Head width | Interorbital distance | Internarial distance |
| Snout-vent length | Head width | Head width | |||
| Oaxaca | 9 | 71.1-87.5 | 25.4-29.1 | 63.0-71.4 | 11.9-13.8 |
| (80.7) | (27.9) | (67.1) | (12.9) | ||
| Coast of Michoacán | 5 | 72.0-79.2 | 24.3-27.2 | 67.0-73.8 | 13.7-14.4 |
| (74.8) | (25.6) | (71.4) | (14.1) | ||
| Colima | 4 | 71.7-79.6 | 26.1-28.6 | 70.5-75.3 | 16.0-17.9 |
| (74.8) | (27.4) | (72.0) | (16.6) | ||
| Tepalcatepec Valley | 2 | 63.0-65.4 | 28.3-32.2 | 57.3-62.4 | 17.0-20.2 |
| (64.2) | (30.3) | (59.9) | (18.6) | ||
| Sinaloa | 11 | 71.9-81.3 | 24.0-27.3 | 70.5-78.1 | 15.0-17.3 |
| (77.3) | (25.7) | (73.4) | (16.1) |
All specimens from Michoacán and Colima more closely approach Diaglena reticulata than D. spatulata. The acquisition of additional specimens, especially from the area between Sinaloa and Colima and from Guerrero, is necessary to determine the relationships among the various populations known at present. Both species of Diaglena inhabit tropical scrub forest; none has been found in the more humid and tropical semi-deciduous forests. Humid forest replaces the scrub forest in the lowlands of southern Nayarit and northern Jalisco; possibly this forest acts as a barrier to the distribution of Diaglena and thus serves as a divider between the ranges of D. spatulata to the north and D. reticulata to the south.
Pternohyla fodiens Boulenger
Pternohyla fodiens Boulenger, Ann. Mag. Nat. Hist., ser. 5, 10:326, 1882.—Presidio, Sinaloa, México.
Nueva Italia (2).
These specimens (JRD 5994-5) were found on the road near Nueva Italia during a heavy rain on the night of August 25, 1960, by James R. Dixon. Both are females having snout-vent lengths of 64.0 and 59.0 mm. They are typical of the species as it is known from Sinaloa, Nayarit, Jalisco, and Colima.
These specimens constitute the southernmost record for the species, which ranges in semi-arid habitats from southern Arizona southward along the Pacific lowlands of México to Colima and inland on the Mexican Plateau in Jalisco.