Hemidactylus fragilis Calabresi, 1915

Mazuch, Tomáš, Šmíd, Jiří & Bauer, Aaron M., 2016, Rediscovery and a new record of Hemidactylus laevis (Reptilia: Gekkonidae) from Somaliland, with notes on and resurrection of Hemidactylus fragilis, Zootaxa 4117 (4), pp. 529-542 : 536-538

Resurrection of Hemidactylus fragilis Calabresi, 1915

We examined all specimens previously identified as H. fragilis , which are: (1) the holotype (MZUF 707; adult male; Somalia, Bur Meldac [=Meel Daaq]); (2) MSNG 53212 (adult female; Ethiopia, Dolo); (3) MSNG 53213 (adult female; Somalia, Rahanuin). Their distribution is summarized in Fig. 1 B. Hemidactylus fragilis has the following combination of morphological characters: (1) small size with maximum recorded SVL 31.5 mm for the male and 37.2 mm for females ( Fig. 5 B,C,D); (2) dorsum with subimbricate scales ( Fig. 5 H) with a few enlarged, smooth, flat tubercles on flanks of posterior half of body, usually in one or two rows on each side; (3) no enlarged tubercles on postero-dorsal side of thighs; (4) subcaudals slightly enlarged only on first three whorls; (5) six enlarged tubercles on each whorl of the tail ( Fig. 5 E); (6) tail conical without basal constriction ( Fig. 5 D); (7) 26 preano-femoral pores in the male; (8) three lamellae under the 1st, five under the 3rd, seven under the 4th toe; (9) 7–8 infralabials and 8–9 supralabials; (10) snout forming a convex line between eye and nostril in lateral view; (11) anterior postmentals in narrow median contact ( Fig. 5 G); (12) anterior postmentals only in contact with first infralabials ( Fig. 5 G); (13) length to width ratio of anterior postmentals 1.35–1.66; (14) 8–9 gulars in the first row behind postmentals ( Fig. 5 G); (15) four dark transverse bands on dorsum between axilla and groin, one on neck and one on occiput; distinct dark line from nostrils through eyes and ear openings to shoulder region and continuing diffusely to inguinal region; three dark bands on dorsum of anterior half of the tail ( Fig. 5 B,C,D,E).

Hemidactylus fragilis can be distinguished from H. frenatus , with which it has been synonymized, by the following characters (condition in H. frenatus in parentheses): smaller size with max. SVL 37.2 mm (versus 50–60 mm); subimbricate dorsal scales (versus juxtaposed); few scattered enlarged tubercles on caudal part of flanks in one or two rows on each side ( Fig. 5 C) (versus enlarged dorsal tubercles in irregular rows, usually well developed posteriorly); larger dorsal scales, 11–12 in eye diameter (versus smaller, 15–17 in eye diameter); less elongated anterior postmentals, length to width ratio 1.35–1.66 (versus 1.62–2.6; Fig. 5 F,G); 8–9 gular scales in the first row behind postmentals (versus 12–15; Fig. 5 F,G); color pattern composed of dark transverse bands on dorsum (versus pattern lacking transverse bands, usually longitudinally striped or patternless; Fig. 5 B,C,D,E). Morphological differences between the two species are summarized in Table 2 . Based on this evidence we resurrect H. fragilis from the synonymy of H. frenatus .

H. laevis (n=2) H. laticaudatus H. fragilis (n=3) H. frenatus (n=12) (n=22)

Hemidactylus fragilis differs as follows from the species that can be found or are expected to occur in the Horn of Africa: Hemidactylus angulatus , H. arnoldi , H. awashensis , H. barbierii , H. barodanus , H. bavazzanoi , H. citernii , H. granchii , H. jubensis , H. laevis , H. laticaudatus , H. mabouia , H. macropholis , H. mercatorius , H. mrimaensis , H. platycephalus , H. puccionii , H. robustus , H. ruspolii , H. sinaitus , H. smithi , H. taylori , and H. yerburii pauciporosus have enlarged dorsal tubercles on the whole dorsum, nape and head. Hemidactylus somalicus does not have depressed body habitus, has very small proximal subdigital lamellae, scarcely larger than the granules on the sole, tail without enlarged tubercles, and first supralabial excluded from nostril. Hemidactylus albopunctatus , H. funaiolii , H. isolepis , H. klauberi , H. megalops , H. modestus , H. ophiolepis , and H. ophiolepoides have homogenous dorsal scales and weakly developed subdigital lamellae, head short and not depressed, and tail without enlarged tubercles. Hemidactylus barbouri , H. squamulatus , and H. tropidolepis have heterogeneous dorsal scales without tubercles, some or all scales are keeled, well developed enlarged tubercles on nape and occiput, and head and body not depressed. Hemidactylus flaviviridis is larger (maximum SVL about 95 mm), has swollen, carrot-shaped tail clearly constricted at its base, and dorsal scales small, granular and juxtaposed. Hemidactylus curlei has swollen, carrot-shaped tail clearly constricted at its base, scales on tail large, sub-imbricate and without enlarged tubercles, no enlarged tubercles in sacral region, and males with 4 precloacal pores.

Figures

FIGURE 1. (A) Map of Somaliland and the adjoining part of Somalia showing the distribution of Hemidactylus laevis (red circle—type locality, Gaan Libah; blue circle—new record, Erigavo); (B) Map of the Horn of Africa showing the distribution of H. laticaudatus (green squares) — 1: Harar (type locality); 2: Lalibela; 3: Gondar, Azezo, Fiume Caha; 4: Axum; 5: Adwa; 6: 32 km E of Neghelli; 7: Asmara; 8: Saganeiti (type locality of H. fossatii) and H. fragilis (yellow triangles) — 1: Bur Meldac (type locality); 2: “ Rahanuin; 3: Dolo. Records of H. laticaudatus are from Scortecci (1928), Largen (1997), Largen & Spawls (2006, 2010), and own unpublished data.

FIGURE 5. (A) A topotype adult male of Hemidactylus laticaudatus from Harar, Ethiopia; (B) The holotype of Hemidactylus fragilis (MZUF 707) from Bur Meldac, Somalia; (C) adult female of H. fragilis (MSNG 53212) from Dolo Odo, Ethiopia, with regenerated tail; (D) female of H. fragilis (MSNG 53213) from Rahanuin, Somalia, with partially regenerated tail; (E) detail of the tail of the previous specimen, note the enlarged tubercles on the original part of tail; (F) detail of mental region of H. frenatus (MZUF 27607) from Mogadishu, Somalia; (G) detail of mental region of H. fragilis (MSNG 53213) from Rahanuin, Somalia; (H) detail of dorsolateral sub-imbricate scales of H. fragilis (MSNG 53213) from Rahanuin region, Somalia.

Tables

TABLE 2. Comparison of diagnostic characters of H. laevis, H. laticaudatus, H. fragilis and H. frenatus. Most distinctive characters between H. fragilis and H. frenatus are in bold. (* counted longitudinally; ** measured in the middle of each scale).

Maximum SVL (mm)	39	62.0	37.2	60.0
Enlarged tubercles on dorsum	Developed, but smaller and in fewer regular rows	Well developed, higher number of regular rows	Few scattered on flanks in second half of body, in one or two rows on each side	Rather irregular rows, usually well developed in second half body
Dorsal lepidosis	Juxtaposed	Juxtaposed	Sub-imbricate	Juxtaposed
Number of dorsals in the eye diameter (*)	11–12	9–11	11–12	15–17
Tubercles on postero-dorsal side of thighs	No	Yes	No	No
Enlarged tubercles on tail	No	Yes	Yes	Yes
Tail with basal constriction	Yes	Yes	No	No
Length to width ratio of anterior postmentals (**)	1.54–1.77	1.35–1.69	1.35–1.66	1.62–2.6
Number of gulars in first row behind postmentals	8–12	8–12	8–9	12–15
Dark transverse bands on dorsum	Yes	Yes	Yes	No