Ameiva erythrocephala, Daudin, 1802

Harvey, Michael B., Ugueto, Gabriel N. & Gutberlet, Ronald L., 2012, 3459, Zootaxa 3459, pp. 1-156 : 92-93

Ameiva erythrocephala Group

Definition.— The following combination of characters distinguishes the Ameiva erythrocephala Group ( Table 7) from other groups of Ameiva : frontal entire, its posterior suture usually contacting third supraocular (except in A. fuscata ) or aligned with suture between second and third supraoculars; interparietal frequently divided longitudinally (except A. erythrocephala ); parietal series (including interparietal) composed of five (only three in single specimen of A. major examined), short and somewhat irregularly round plates; narial suture behind nostril and touching it; first supralabial usually toothy; first subocular usually contacting supralabials (except A. erythrocephala ); intertympanic crease present; pectoral sulcus separating 2–4 transverse rows of ventrals; ventral scales in 10–20 longitudinal rows (most taxa with 10 rows, A. pluvianotata with 12, A. fuscata with 12–14, A. cineracea and A. major with 18–20 rows); plate-like antebrachial scales broadly separated from brachial scales; combined femoral and abdominal pores 39–78; fifth toe well-developed (except some A. griswoldi ); supradigital and subdigital lamellae contacting one another, at least on Toes IV and/or V (except A. fuscata ); generation glands present (except A. fuscata and A. pluvianotata ); tip of snout reddish in adult males (only with slight reddish cast in A. plei ; condition of melanic species A. atrata , A. corvina and A. corax unknown); ontogenetic changes in coloration absent or very limited in all species except A. fuscata , A. plei and A. pluvianotata which undergo considerable changes (condition not corroborated in A. griswoldi , but Schwartz and Henderson [1991] do not mention juveniles as having different coloration than adults); adult males completely melanic or without dorsolateral and vertebral stripes, except A. erythrocephala which has relatively distinct dorsolateral and upper lateral pale stripes; flanks without pale ocelli (except A. fuscata which has black-margined pale blue ocelli rather reminiscent of those in the A. ameiva Group) but most species with pale spots, sometimes merging and forming short transverse bands (e.g., A. griswoldi , A. plei ); hemipenis with more distal (16–19) than proximal (7–13) laminae; discontinuous laminae absent; asulcate expansion pleat well-developed.

Content.— Ameiva atrata Garman , A. cineracea Barbour and Noble , A. corax Censky and Paulson , A. corvina Cope , A. erythrocephala Daudin , A. fuscata Garman , A. griswoldi Barbour , A. major Duméril and Bibron , A. plei Duméril and Bibron , A. pluvianotata Garman.

Distribution.—Lesser Antilles from Sombrero Island south to Dominica.

Remarks.— Species of this group have short and somewhat irregularly rounded parietal scales that are unlike those of any other species in the remaining groups of Ameiva . Among other teiids, frequent longitudinal division of the interparietal only occurs in the Cnemidophorus murinus and C. vanzoi Groups. Ameiva chrysolaema is the only other teiid that shares a pectoral sulcus with the A. erythrocephala Group.

Ameiva cineracea and A. major are included in this group with slight reservation. Both are Lesser Antillean endemics considered extinct on the island of Guadeloupe and the Grand Îlet off Petit-Bourg on the east coast of Basse-Terre, Guadeloupe ( Schwartz & Henderson 1991; Breuil 2002). Both taxa have noticeably more longitudinal rows of ventral scales than other members of the group ( A. cineracea has 18–20 rows and A. major has 18 rows according to Schwartz & Henderson 1991, vs. 10–14 in all other members of the group). We were only able to examine photographs of the head from the type specimen of A. major (MNHN 1491) and, thus, these elevated counts could not be verified. However, examination of the head squamation of A. major reveals similarities with other species of the A. erythrocephala Group. With the group, A. major shares a longitudinally divided interparietal, conspicuously short parietals, narial suture behind nostril, first supralabial toothy and first subocular contacting supralabials. Additionally, the drawing of the type specimen in the original description clearly shows that the enlarged antebrachial scales are separated from the brachial scales by a wide gap of small scales, as in all other members of the A. erythrocephala Group. Therefore, it seems appropriate to include A. major in the A. erythrocephala Group.

Ameiva fuscata from Dominica is the southernmost member of the A. erythrocephala Group and the closest geographically to the A. ameiva Group represented by A. ameiva tobagana on St. Vincent, Grenada, and the Grenadines. Interestingly, A. fuscata also shares several morphological similarities with the A. ameiva Group such as the posterior suture of the frontal usually contacting the second supraocular, scales separating the supradigital and subdigital lamellae along the postaxial edge of each toe, a pectoral sulcus separating only two transverse rows of ventrals in this species whereas it separates 3–4 in all other A. erythrocephala Group species, a distinct ontogenetic change in coloration, presence of pale blue ocelli on the flanks of males, and absence of generation glands. However, other characters such as a longitudinally divided interparietal, short parietal scales, nostril in front of the narial suture, a toothy first supralabial, contact between the first subocular and supralabials, a large gap of smaller scales separating the enlarged series of brachials from enlarged antebrachials, and a long fifth toe indicate that this species is related to the other Ameiva of the Lesser Antilles.

Ameiva fuscata and A. pluvianotata share preanals 10–17 (vs. 4–8 in other Ameiva ), preanal plate single and much larger than the scale in front of it (paired or variable in other Ameiva ), and generation glands absent (also in A. ameiva Group).