Lycophidion laterale Hallowell, 1857

Sánchez-Vialas, Alberto, Calvo-Revuelta, Marta & Riva, Ignacio De La, 2022, Synopsis of the terrestrial Reptiles of Equatorial Guinea, Zootaxa 5202 (1), pp. 1-197 : 116-119

Lycophidion laterale Hallowell, 1857

Figure 29C

Lycophidion laterale Hallowell, 1857: 58 . Type locality: “ Gabon ”.

Lycophidium polylepis Boulenger, 1919: 21 . Type locality: “Madié (Ituri)”.

Distribution. It extends from Liberia to the East of the Democratic Republic of the Congo. It has been included in the fauna of Bioko ( Wallach et al. 2014), although there are no precise confirmed records for the island. The occurrence of this species in Río Muni is herein confirmed ( Map 33C ).

Comments. We herein provide the first confirmed record of this species for Río Muni. The body colour pattern of the Biokoan specimens housed at the MNCN and the one from Río Muni at the EBD, is congruent with the phenotype shown by some Cameroonian specimens of L. laterale (see a picture in Spawls et al. 2004), suggesting that this pattern is present, at least, in the coastal areas and surroundings from Cameroon to Río Muni. This pattern consists of several distinct and asymmetric paired large orange-yellowish spots, arranged along the entire dorsal surface, which in the examined specimens are usually fused, resulting in an irregular banded body pattern. Populations from Gabon, Republic of the Congo and Angola exhibit a different dorsal pattern, with a brown background, either patternless or with very small and isolated black dots arranged along the paravertebral axes ( Guibé & Roux-Estève 1972; Pauwels et al. 2017; Chippaux & Jackson 2019). The specimens of Lycophidion collected by M. Iradier –currently housed in the MNCN– were referred in Iradier (1887: 464) but, unfortunately, with no data on their specific collection locality. Pérez del Val (2001) listed these specimens as L. irroratum ( Leach, 1819) without any discussion, and tentatively suggested Río Muni as their collection locality (“ Rio Muni?”). However, the information reviewed at the documentation department of the MNCN regarding the housed specimens of Lycophidion , indicates that these specimens were bought by the MNCN to Manuel Iradier in 1878, and that they, among others, were collected in “ Fernando Poo ” (=Bioko). An old catalogue card, handwritten by Antonio de Zulueta, also indicates Bioko as the collection site. No more specimens of this species have been recorded nor found in other examined collections. Bocage (1895a) reported the presence of another congeneric species in Bioko, Lycophidion capense , based on two specimens, one of them from “Natividad” and the second one with unknown origin. Mertens (1964) argued that Bocage’s record could be an identification mistake for other species of Lycophidion or with Chamaelycus fasciatus , as the range of L. capense is characterized by open and dry savannas, away from the tropical forests of Central Africa. There is a chance that the specimens examined by Bocage (1895a) could belong to L. laterale but considering the striking pattern of the specimens from Equatorial Guinea (see below) it seems unlikely that Bocage (1895a) did not notice the differences between the patternless species L. capense and the banded L. laterale . Additional fieldwork is required to confirm the presence of L. laterale in Bioko.

Specimens examined. Eight specimens. Río Muni: Miboman, December 1987 ( EBD 27752). Bioko: without specific locality (1876–1877) ( MNCN 23102–23108 ) .

Figures

FIGURE 29. From left to right: lateral, dorsal and ventral views of the head of: Hormonotus modestus (A) (EBD 24957), Limaformosa guirali (B) (EBD 27782), and Lycophidion laterale (C) (MNCN 23108). Photos:AS-V.

MAPS 33 A–C. Distribution maps for Equatorial Guinean records of (A) Hormonotus modestus; (B) Limaformosa guirali; (C) Lycophidion laterale (question mark represents an imprecise record).