Calappa japonica Ortmann, 1892

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 : 2853-2856

Calappa japonica Ortmann, 1892

( Figure 1A–C )

Calappa japonica Ortmann 1892, p 566 , Plate 26, Figure 8 ; Sakai 1937, p 96, Plate 18, Figure 4 ; Barnard 1950, p 352, Figure 66n–p; Grindley 1961, p 132; Sankarankutty and Subramanian 1976, p 21; Galil 1997, p 300 –303, Figures 10d , 13d , 15 , 32; Komai 1999, p 73.

Calappa exanthematosa Alcock and Anderson 1894, p 177 ; 1895, Plate 15, Figures 1, 1a ; Alcock 1896, p 146.

Calappa cf. pustulosa: Türkay 1986, p 150 –151 [not Calappa pustulosa Alcock, 1896 ].

Material examined

Central Red Sea : RV Valdivia, St. VA 22/122 TA, in front of Ras el Aswad south of Jeddah , Saudi Arabia, 21 ° 229N, 39 ° 049E, depth 383– 363 m, 17 April 1978: three juvenile males ( SMF 13592, identified as Calappa cf. pustulosa ); RV Valdivia, St. VA 22/ 111 TA, 21 ° 289370N, 38 ° 159350E, depth 740–785 m, 12 April 1979: one juvenile ( SMF 13585, identified as Calappa cf. pustulosa ). Southern Red Sea: RV Akademik Kurchatov, St. 3097, Cruise 30, 18 ° 38994N, 40 ° 159952E, depth 640– 615 m, pteropodous mud, 8 January 1980: one female (moult cast) ( IORAS unregistered). Gulf of Aden: probably taken by some Russian fisheries research expedition, exact locality unknown: one male, one female ( ZMMU Ma 5344–5345), identified as Calappa aff. pustulosa . Gulf of Oman: Iran, no exact locality, found on the beach, Reza Fatemi coll.: one female ( SMF 29501) . Japan: exact locality unknown, T. Sakai collection: one female ( SMF 22942) .

Type locality

Japan, Bay of Tokyo .

Type material

Two males and one female syntypes, MZUS 111 (dry) ( Komai 1999).

Size ( CL × CW)

Juvenile specimens from the Red Sea ( SMF 13592): 13.6×15.9, 13.3×15.4, and 6.9× 7.4 mm; male from the Gulf of Aden: 46.4× 61.6 mm; female from the Gulf of Oman: 56.3× 77.9 mm; specimens from Japan: 53.5×70.2 and 96.6× 133.7 mm.

Habitat

Outside the Red Sea the species is known from 30 to 380 m depth. In the Red Sea it occurs between 363 and 785 m. The habitat in the Red Sea where the IORAS specimen was collected, was observed from the submersible Pisces and characterized as ‘‘small plateau in front of the steep rift zone covered with pteropodous mud’’. In the Gulf of Aden the species was collected together with the swimming crab Charybdis smithii MacLeay, 1838 , known to inhabit muddy substrates in a depth range from approximately 200 to 300 m ( Türkay and Spiridonov 2006).

Distribution

Southern to central Red Sea, Gulf of Aden, Gulf of Oman, Arabian Sea, East to South Africa, Gulf of Bengal, East China Sea, Japan.

Remarks

Sakai (1937) was the first author to synonymize C. exanthematosa Alcock and Anderson, 1894 with C. japonica . Galil (1997) followed this view. Our specimens from the Gulf of Aden and the Gulf of Oman show no considerable differences to those from Japan with regard to the carapace and cheliped sculpture, the shape of the basal antennal segment, and the morphology of the Go/2. However, the carapace of the juvenile specimens from the Red Sea have a subcircular rather than an elliptical shape and, in general, more distinct tubercles and stronger granulation than those from Japan. The smaller the crabs are, the more these characters are expressed and might lead to confusion with C. pustulosa . The tubercle pattern, however, is the same as in adult specimens from the Gulf of Aden and from Japan, and the basal antennal segment is very similar to other specimens of C. japonica examined ( Figure 1A–C ). Thus the specimens from the Red Sea are considered as belonging to C. japonica and the differences in carapace shape and granulation are considered to be size-dependent variation.

Calappa pustulosa Alcock, 1896 ( Figure 1D )

Calappa pustulosa Alcock 1896, p 147 , Plate 6, Figure 1 ; Sakai 1937, p 97, Plate 18, Figures 2 , 3 ; Sakai 1976, p 134, Plate 41, Figure 1 ; Dai and Yang 1991, p 106, Text figure 52, Plate 12, Figure 1 ; Galil 1997, p 311 –312, Figures 17e, 20e, 22, 23.

nec Calappa cf. Pustulosa: Türkay 1986, p 150 –151, Plate 1, Figures 4 , 5 [5 Calappa japonica ].

Material examined

South-western Indian Ocean : Strait of Mozambique, 25 ° 00.09S, 35 ° 19.99E, depth 228 m, shrimp trawl, RV Vitiaz, Cruise 17, St. 2635, M. V. Heptner coll.: one female ( ZMMU Ma 5355). No exact locality: probably Japan, T. Sakai collection: one male ( SMF 22939) .

Type locality

Off Ganjam and Orissa coasts, Gulf of Bengal .

Type material

Probably in the ZSI. Number of specimens (syntypes) not known.

Size ( CL × CW) Specimen from the Strait of Mozambique: 54.6× 60.3 mm; specimen from Japan:

33.7× 37.1 mm.

Habitat

On sandy or muddy bottom. The present record extends the known depth range which is now from 40 to 228 m.

Distribution

The present record extends the known range to the south-western Indian Ocean, i.e. the Strait of Mozambique. Further distribution range: Maldives, Bay of Bengal, Andaman Sea, Philippines, south China Sea, Japan.

Remarks

Both examined specimens agree well with existing descriptions and illustrations with regard to the carapace and cheliped morphology and the shape of the basal antennal segment ( Figure 1D ). The tubercles in the large specimen from the Strait of Mozambique are somewhat more smoothed than in most C. pustulosa , including our specimen from Japan.

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 4. Gonopods 1 and 2 (Go/1 and 2). (A) Mursia bicristimana, left Go/1, CL 50.0 mm (ZMMU Ma 5353); (B) M. bicristimana, left Go/1, proximal part, same specimen as in (A); (C) M. bicristimana, right Go/2 inserted in Go/1, CL 48.4 mm (SMF 22942); (D) Mursia minuta, left Go/1, holotype, CL 17.1 mm (NHM 1907.5.22); (E) M. minuta, left Go/2, terminal part, same specimen as in (D); (F) M. minuta, left Go/2, same specimen as in (D).

Figure 5. Mursia bicristimana, male, Gulf of Aden, CL 48.4 mm (SMF 22942). (A) Dorsal view; (B) ventral view.

Figure 8. Merus of left last ambulatory leg, posterior view. (A) Mursia bicristimana, CL 48.4 mm, (SMF 22942); (B) Mursia aff. danigoi, CL 52.5 mm (IORAS, unregistered); (C) Mursia minuta, male, CL 19.5 mm (NHM 1898.8.26.3).

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.

Figure 13. Cheliped palm. (A) Mursia coseli, male holotype, CL 21.6 mm (MNHN B.25584); (B) M. aff. danigoi, CL 52.5 mm (IORAS, unregistered); (C) Mursia danigoi, male paratype, 26.8 mm (MNHN B.22371).

Figure 15. Distribution of Mursia species in the Indian Ocean.