Odontodactylus scyllarus ( Linnaeus, 1758 )

Brokensha, Rouane, Landschoff, Jannes & Griffiths, Charles, 2025, Taxonomic guide to the mantis shrimps (Crustacea: Stomatopoda) of South Africa, Zootaxa 5713 (1), pp. 1-93 : 31-33

Odontodactylus scyllarus ( Linnaeus, 1758) , new record

( Fig. 12 )

Cancer scyllarus Linnaeus, 1758: 633 [type locality Rinca , Greater Sunda Island, Sulawesi, Indonesia, by neotype selection

(Ahyong 2001: 85)]. Gonodactylus bleekeri A. Milne-Edwards, 1868: 65 , footnote [ type locality Batavia, Jakarta, Indonesia]. Gonodactylus elegans Miers, 1884: 566 , 575, pl. 52: fig. b [ type localities Providence Island and Providence Reef, Seychelles].—

Kemp, 1913: 4, 11, 134, 139. Odontodactylus scyllarus .— Manning, 1967c: 10–15, fig. 3.— Manning, 1970a: 1431, table 1.—Ahyong, 2001: 85, fig. 41.—

Ahyong et al., 2008: 29–30, fig. 22.— Ahyong, 2012: 39–42, figs. 18, 19.— Poupin et al., 2019: 8, fig. 3B.

Material examined. KZN: SAMC-A079410 , 1 ♀ (TL 88 mm), Sodwana Bay, 1988, depth unknown, coll. W. Emmerson.

Other material examined. Mozambique: SAMC-A019341 , 1 ♂ (TL 129 mm), Inhassoro, 21°32’04.9”S 35°12’07.9”E, depth unknown, stat. PEA 23 A , UCT Ecological Survey, det. R. B. Manning .

Diagnosis. Ocular scales oblique to midline, appressed medially, margin truncate. A2 scale with entire margin setose, anterior setae shorter. Rostral plate triangular; lateral margins convex; apex deflexed. Raptorial claw dactylus with 2 or 3 small teeth on inner margin. AS (3)4–5 with posterolateral spine. Telson mid-dorsal surface with distinct MD carina and 3 longitudinal carinae either side of midline (double accessory MD, anterior SM) in addition to carinae of primary teeth; carina of IM denticle short, not extending onto mid-dorsal surface. Uropodal exopod proximal distinctly longer than distal segment; outer margin with 10–12 flattened movable spines, apices sharp, evenly tapering.

Colour in alcohol. Somewhat faded with evidence of overall diffuse spots. Dactylus of raptorial claw orange along outer margin.

Colour in life (after Ahyong 2012). Overall dorsal colour reddish-brown to green, often with diffuse banding and dark lateral spot on each somite. Large males deep green. Posterior margin of thoracic and abdominal somites orange-red. Carapace with anterolateral and usually posterolateral areas with large dark brown spots outlined in white. A2 scale orange-yellow with dark apex; setae red. Ventral surface, dactylus of raptorial claw and pereopods red. Uropodal protopod pale basally; exopod blue with iridescent blue outline and red marginal setae; endopod dark blue with iridescent blue outline and red marginal setae.

Measurements. ♂ (n = 1) TL 129 mm, ♀ (n = 1) TL 88 mm. CI ( ♀) 500. Manning (1967c) reported specimens to TL 171 mm.

Distribution and habitat. Western Indian Ocean from Mozambique, Madagascar, Comoros, Réunion, Mauritius and Seychelles to South China Sea, Japan, New Caledonia, Fiji, northern New Zealand, Australia, and now South Africa [KZN]. Associated with hard bottom substrates, such as rock and rubble in shallow waters; 0– 100 m.

Remarks. Known as the ‘peacock mantis shrimp’, Odontodactylus scyllarus is one of the most recognisable species with the fastest and most powerful punch of the ‘smashers’ and high popularity in the aquarium trade. The raptorial claw biomechanics ( Patek et al. 2004) and visual system of this well-known warm-water species has been well-researched. However, this female specimen collected from Sodwana Bay, KZN, is the first specimen of the species to be taxonomically examined from South Africa. Although an infrequent but definite animal sighting by divers on excursions in KwaZulu-Natal, O. scyllarus has never been documented from South Africa in scientific literature. Meanwhile, it has been repeatedly mentioned in early revisions of South African stomatopod fauna ( Barnard 1950; Manning 1969a) that the presence of O. scyllarus on the east coast of South Africa is highly feasible. This is now confirmed. The species has been recorded from multiple localities along the coast of eastern Africa including southern Mozambique ( Barnard 1958), Madagascar ( Manning 1970a), Comoros ( Mayotte), Réunion, Mauritius and Seychelles ( Ahyong 2012).

The single South African specimen closely agrees with the most recent revisions of the species (Ahyong 2001, 2012). The specimen has posterolateral spines on abdominal somites 3–5 ( Fig. 12F ) and two small teeth on the inner margin of the dactylus of the raptorial claw ( Fig. 12B ) as well as 10–11 movable spines on the outer margin of uropodal exopod ( Fig. 12H, I ). The Mozambican specimen examined herein and the specimen from Madagascar ( Manning 1970a) both exhibited the same ornamentation of the raptorial claw and abdominal spination as the South African specimen.

PROTOSQUILLIDAE Manning, 1980

Protosquillidae Manning, 1980: 366 , 369.

Diagnosis (after Ahyong 2012). Rostral plate trispinous. Antennal protopod dorsally with fixed, anteriorly directed spine or tooth. Raptorial claw with subterminal ischiomeral articulation; propodus occlusal margin sparsely pectinate; dactylus with smooth or microscopically serrated occlusal margin and strongly inflated heel on outer proximal margin. Telson and AS 6 immovably fused, forming pleotelson (though demarcation usually visible). Distal segment of uropodal exopod articulating at distal end of proximal segment; distal movable spines on outer margin of proximal segment not recurved anteriorly.

Composition. Chorisquilla Manning, 1969c ; Echinosquilla Manning, 1969c ; Haptosquilla Manning, 1969c ; Protosquilla Brooks, 1886 ; Rayellus Ahyong, 2010a ; Siamosquilla Naiyanetr, 1989 .

Remarks. One genus and species is known from South Africa.

Figures

FIGURE 12. Odontodactylus scyllarus (Linnaeus, 1758), ♀, TL 88 mm, SAMC-A079410.A, anterior cephalothorax, dorsal; B, right raptorial claw, lateral; C, TS6–8, right lateral; D, TS8 sternal keel, left lateral; E, right antennal protopod, lateral; F, AS1–5, right lateral; G, telson, right lateral; H, right uropod, ventral; I, AS5–6, telson and right uropod, dorsal. Scale A–B, E, G–I = 5 mm, C, F = 10 mm, D = 2.5 mm.