Gonodactylus botti Manning, 1975b

Gonodactylus botti Manning, 1975b

( Fig. 8 View FIGURE 8 )

Gonodactylus chiragra . — Holthuis, 1967b: 26, 41 [list], fig. 7a.— Tirmizi & Manning, 1968: 21, fig. 7. [ Not G. chiragra ( Fabricius, 1781) ].

Gonodactylus botti Manning, 1975b: 289 , fig. 1 [ type locality Jakarta, Indonesia].— Manning & Lewinsohn, 1986: 5, 15 [list], fig. 3.—Manning, 1990: 97, 104 (key).— Cappola & Manning, 1995: 274–275.— Ahyong, 2005: 159.—Brokensha et al. 2023: 164–165, fig. 8.

Not Gonodactylus botti .— Moosa, 1991: 155 [= Gonodactylellus affinis ( de Man, 1902) ].

Material examined. KZN: SAMC-A015632 , 1 ♂ (TL 63 mm), 8 ♀ (TL 10–66 mm), Jesser Point, Sodwana Bay, 27°32’33”S 32°40’50.0”E, 2 Aug 1976, 13.5 m, RW 26, coll GoogleMaps . R. Winterbottom, det. S. Ahyong ; SAMC-A015631 , 21 ♂ (TL 18–57 mm), 60 ♀ (TL 10–71 mm), Sodwana 6.5 km north of Island Rock , 27°13’21”S, 32°47’48”E, 28 Jul 1976, 13.5 m, RW 76-22, same as above GoogleMaps .

Diagnosis. Ocular scales broad, flattened, separate, together slightly broader than 0.50 rostral plate width, anterior margins transverse. Rostral plate basal portion with anterior margins slightly concave; anterolateral angles rounded; lateral margins divergent anteriorly; apical spine just longer than base. Lateral margin of TS6 broader than TS7. Telson with LT tooth indicated by shallow notch in margin of telson between anterolateral angle and apex of IM tooth; mid-dorsal carinae blunt, neither sharp nor crested dorsally and strongly inflated in adults; MD carina unarmed posteriorly; accessory MD carinae forming “anchor”; with 8–13 SM denticles. Uropodal exopod proximal segment outer margin with 12 movable spines.

Colour in alcohol. Faded yellow, but with scattered blue pigment on all limbs and uropods. Dactylus of raptorial claw and uropodal endopod blue. Raptorial claw with ‘meral spot’ white. Colour in life unknown.

Measurements: ♂ (n = 1) TL 63 mm, ♀ (n = 8) TL 10–66 mm. A1 peduncle 0.51–0.67CL. A2 scale 0.52– 0.67CL. AWCLI 714–852.

Distribution and habitat. Reported from Indonesia to Western Indian Ocean from Pakistan, Red Sea, Persian Gulf, Somalia and South Africa; 0–13.5 m ( Ahyong 2005). Found in coral reefs, both sandy and rocky tidal pools at the base of dead coral.

Remarks. Although common in the Western Indian Ocean, G. botti has not been well-studied. Since its description, seemingly from Jakarta, Indonesia, the species has only been recorded with any confidence from the Western Indian Ocean (Ahyong 2001). After intensive and unsuccessful sampling of Indonesia for the species, the type material from the Pacific is suspected to have originated in the Western Indian Ocean (Ahyong 2001) and specimens from the west of Pakistan are considered the only records that can be identified with certainty as G. botti ( Ahyong 2005) . Moosa’s (1991) singular Pacific Ocean account of G. botti from New Caledonia is referrable to Gonodactylellus affinis ( de Man, 1902) ( Ahyong 2005) .

The distributional disjuncture and erroneous identifications highlight the difficulty in distinguishing this understudied species. In southern Africa, preserved museum specimens of G. botti have been mistaken for and labelled as G. chiragra . The rostral plate is distinguished in the two species by the anterior margins being only slightly concave in G. botti versus being distinctly concave in G. chiragra , but the latter shows variation in which it approaches G. botti in this character. Live and freshly preserved specimens can easily be distinguished by the colour of the ‘meral spot’ of the raptorial claw: white for G. botti and maroon to dark blue for G. chiragra . The more inflated mid-dorsal carina of the telson also distinguishes G. botti from G. chiragra in specimens over 23 mm (Ahyong 2001).