The Amphibians and Reptiles of Sinaloa, Mexico - Smithsonian ...

186 UNIVERSITY OF KANSAS PUBLS., MUS. NAT. HIST.
the black spots on the tips of the dorsal scales that are characteristic
of the adults.
Morphological variation in this species has been reported by
Ortenburger (1928:137) and by Smith (1943a:447-48). Zweifel
and Norris demonstrated (1955:242) that the head length/bead
width ratios of Masticophis fiagellum and M. striolatus are different.
The sympatric distributions of M. fiagellum and M. striolatus were
reported by Bogert and Oliver (1945:364).
This large diurnal snake is common in open areas, near cultivated
regions, and around heavily grazed grassland interspersed with
forest. This species is primarily terrestrial but, on occasion, has
been seen three to four meters above ground in dense vegetation.
Distribution in Sinaloa,—Masticophis striolatus has been reported
from various localities throughout the lowland thorn woodland at
elevations up to 600 meters in the northern part of the state, and also
hi tropical deciduous forest up to about 2000 meters in southern
Sinaloa. See Fig. 75.
Specimens examined.—Ahome (LACM 8647-49); 16 km. NNE Choix, 520
m. ('KU 73572); 1 km. S Conception, 75 m. ("KU 63736); 17,3 ml. N
Culiacan (JFC 63:148); 30 mi. N Culiacan (CSCLB 1957); 22 mi. S Culiacan
(LACM 25921): Guarauchil, 45 m. (* KU 73571); 5 mi. S Guamuchil (*UNM
10193); Isla Palmito del Verde, middle (' KU 73576-78); La Cruz (LACM
7003-04); 2.8 mi. N Los Mochis June. (UAZ 9370); Mazadan (LACM 7005-
06); N edge Mazadan (CSCLB 1950); N Mazadan (JFC 62:60); 13 mi. N
Mazadan (UAZ 16304); 13.8 mi. N Mazadan (UAZ 16305); 5 mi. NW
Mazadan (JRM 1100); Plomosas, 760 m. ('KU 73574-75); Rosario, 150 m.
(* KU 73573); 23.8 mi. SE Rosario (UAZ 16306); 13.9 mi. W San Miguel
(UAZ 9371); Santa Lucia, 1100 m. (°KU 75627); 19.2km. NE Santa Lucia,
1940 m. ('KU 78961); Teacapan (LACM 7009); 2 mi. N Teacapan (LACM
7240); 2 mi. NE Teacapan (LACM 7008); 2.5 mi. E Teacapan (LACM 7010);
10 km. NNW Teacapan ('KU 91425-26); Terreros (LACM 7007).
Literature records.—El Dorado (Fugler and Dixon, 1961:15); Presidio
(Boulettger, 1893:388); 1 mi. N Presidio (Taylor, 1938:524); ". . . on the
highway near the Rio San Lorenzo" (Lewis and Johnson, 1956:280).
Additional records.—14 km. E Concordia, by id. (UAZ 16307); El Dorado
.(AMNH 90734-38); 30 mi. N El Dorado (SU 24112-13); 22.4 mi. S El Fuerte
(UIMNH 39199); 7 mi. NNW Escuinapa (AMNH 75886); 5.2 mi. E La Cruz
(SU 23962); 6.6 mi. N Los Mochis tumoff (SU 23961); 22.2 mi. N Mazadan
(SU 23963); 2 mi. E Mazadan (FMNH 117847); 21 mi. N Pericos (UIMNH
39200); Presidio (FMNH 117832, 117846, 17846 I?]); Rosario (UIMNH
62815); 8 mi. NNW Rosario (UMMZ 112763).
Natrix valida valida (Kennicott)
Regina valida Kennicott, Proc. Acad. Nat. Sci. Philadelphia, 12:334, 1860
(type locality, Durango).
Natrix valida valida: Cope, Proc. U. S. Nat. Mus., 14:670, 1891.
Remarks.—The range and mean for four males and five females
from southern Sinaloa are, respectively, 140-148 (143.8); 139-145
{143.0) ventrals and 77-83 (79.6) (excluding KU 63738); 67-74