Mursia africana Galil, 1993

Spiridonov, Vassily A. & Apel, Michael, 2007, A new species and new records of deep-water Calappidae (Crustacea: Decapoda) from the Indian Ocean with a key to the Mursia Desmarest, 1823 species of the region, Journal of Natural History 41 (45 - 48), pp. 2851-2890 : 2856-2859

Mursia africana Galil, 1993

( Figures 2A, B , 3A, B )

Mursia armata: Barnard 1950, p 356 , Figure 67g [not Mursia armata de Haan, 1837 ]. Mursia africana Galil 1993, p 352 , Figures 1a , 2a, b , 3a, b .

? Mursia africana: Ng et al. 2002, p 356 –357.

Material examined South-western Indian Ocean: off Kenya, 01 ° 189–01 ° 209N, 41 ° 569–41 ° 539E, 177–243 m

depth, trawl, 14–15 January 1965, RV Meteor, Cruise 1, St. 158: one male, one juvenile ( SMF 29497); off Mozambique, 15 ° 05.09S, 35 ° 15.39E, depth 210–230 m, shrimp trawl, RV Vitiaz, Cruise 17, St. 2635: one male ( IORAS uncat.); off Kenya, 03 ° 089S, 40 ° 20.59E – 03 ° 079S, 40 ° 219E, depth 250–255 m, 5 September 1974, A. J. Bruce coll.: one male (holotype, RMNH D 30986) .

Type locality

Off Kenya, Western Indian Ocean.

Type material

See under ‘‘Material examined’’.

Size ( CL × MCW)

Holotype: 30.7× 56.6 mm, LS 59.1 mm; specimen from off Mozambique: 30.4× 53.7 mm, LS 57.3 mm.

Habitat

Trawled at depth range 177–290 m.

Distribution

Along East African coast from Kenya to Mozambique. A record from Thailand by Ng et al. (2002) is questionable, since especially the relative length of the lateral spine is a difficult character to distinguish between M. africana and similar species, such as M. flamma , and use of the key provided by Galil (1993) might lead to misidentifications (see ‘‘Remarks’’).

Remarks

The present specimens agree well with the description of Galil (1993) and the holotype deposited in the RMNH, which has been examined for comparison. Even though M. africana is similar to M. flamma Galil, 1993 , in particular regarding the shape of the Go/2 [compare Figures 3a, b and 10c, d in Galil (1993) and our Figure 3A, B ], the two species are distinguished by the following characters: carapace relatively wider and less convex in M. africana , lacking the additional tubercle between median and mesial branchial row of tubercles which is present in M. flamma ; posterior margin of carapace with flattened, nearly effaced lobes in M. africana and three sharp teeth in M. flamma ; the merus of the cheliped bispinose (but with a minute granular tubercle in addition to the two spines) in M. africana and trispinose in M. flamma . Contrary to the description provided by Galil, the median frontal lobe is more or less triangular in M. africana , while it is more rounded and bulbous in M. flamma .

The relative length of the lateral spines, a character often used for distinction of the species within the genus, however, is subject to considerable size-related variation. In M. africana the LS / CW ratio ranges from 0.35 in small specimens to 0.20 in larger size specimens, while in M. flamma it varies from 0.20 to 0.07. Thus, if this character is used for distinction of the two species the size of the actual specimen needs to be taken into account. Otherwise the use of this character might result in misidentifications.

Figures

Figure 1. Basal antennal segment of Calappa. (A) C. japonica, Red Sea, male, CL 13.6 mm (SMF 13592); (B) C. japonica, Gulf of Aden, male, CL 46.4 mm (ZMMU Ma 5344); (C) C. japonica, Japan, female, CL 53.5 mm (SMF 22942); (D) C. pustulosa, Strait of Mozambique, female, CL 54.6 mm (ZMMU Ma 5335).

Figure 2. Dorsal view of distal margin of cheliped merus. (A) Mursia africana, male, CL 30.4 mm (IORAS, unregistered), left cheliped; (B) M. africana, juvenile male, CL 14.7 mm (SMF 29497), left cheliped; (C) Mursia aff. danigoi, male, CL 52.5 mm (IORAS, unregistered), right cheliped; (D) Mursia bicristimana, male, CL 50.0 mm (ZMMU Ma 5353), right cheliped; (E) M. bicristimana, female, CL 37.0 mm (SMF 22942), right cheliped; (F) Mursia flamma, female, CL 46.3 mm (IORAS, unregistered), right cheliped; (G) Mursia minuta, male holotype, CL 17.1 mm (NHM 1907.5.22), right cheliped; (H) M. minuta, male, CL 19.5 mm (NHM 1898.8.26.3), right cheliped.

Figure 3. Gonopods 2 (Go/2). (A) Mursia africana, left Go/2, abdominal face, juvenile male, CL 14.7 mm (SMF 29497); (B) M. africana, left Go/2, abdominal face, CL 30.4 mm (IORAS, unregistered); (C) Mursia bicristimana, left Go/2, abdominal face, CL 50.0 mm (ZMMU Ma 5353); (D) M. bicristimana, left Go/2, terminal part, same specimen as in (C); (E) Mursia aff. danigoi, left Go/2, terminal part, abdominal face, CL 52.5 mm (IORAS, unregistered).

Figure 10. Mursia minuta sp. nov. (A, B) Male holotype, CL 17.1 mm (NHM 1907.5.22), dorsal and ventral views, respectively; (C, D) male from Laccadive Islands, CL 19.5 mm (NHM 1898.8.26.3), dorsal and ventral views, respectively.