Necallianassa truncata ( Giard & Bonnier, 1890 )

Marin, Ivan, 2021, Burrowing mud shrimps (Decapoda: Axiidea & Gebiidea) of the northeastern Black Sea and their external parasites, Zootaxa 5039 (4), pp. 571-583 : 577

Necallianassa truncata ( Giard & Bonnier, 1890)

( Figs. 1 e–g ; 4 )

Callianassa truncata Giard & Bonnier, 1890: 362 , figs. 2, 4.

Callianassa italica Parisi, 1915: 64 , figs. 1, 2.

Material examined. BLACK SEA, Crimean Peninsula : 2♂♂ ( ZMMU Ma-6189 and Ma-6190), 2 ovigerous ♀♀ ( ZMMU Ma-6191 and Ma-6192)— Kruglaya Bay (Omega), 44°35’51.8”N 33°26’40.8”E, depth 0.5–1.5 m, burrows in fine sand, with yabbi pump, coll. I. Marin, 14.06.2020 ; 6♂♂, 12 ovigerous ♀♀ ( LEMMI)—same locality and date; 1♂, 3 ovigerous ♀♀ ( LEMMI)— Pesochnaya (Sand) Bay , 44°36’33.0”N 33°29’04.8”E, depth 1.5 m, burrows in fine sand, with yabbi pump, coll. I. Marin, 17.06.2020 .

Remarks. From the other two callianassid shrimps mentioned above ( G. candidus and G. tyrrhenus ), the species can be easily separated by the dense setation of the dactylus of the major cheliped in males, and relatively small chelipeds in females (see Figs 1 e–g ; 4 ) and the possession of a spine on the outer margin of the uropodal endopod. The congeneric Necallianassa acanthura , which occurs in the Mediterranean, is readily distinguished from N. truncata by the absence of a spine on the posterolateral border of the telson.

The species has been recorded from the northeastern (Dolgopol’skaya,1954, 1969; Kobyakova&Dolgopol’skaya, 1969; Makarov, 1938, 2004), southeastern ( Mikashavidze, 1981) and southwestern ( Bãcescu, 1967) Black Sea , but these records were considered questionable as these records were based only on larvae (Saint Laurent & Boźić, 1976; Abed-Navandi & Dworschak, 1997).

Parasites. No external parasites were found.

Distribution. The species is widely distributed in the eastern Atlantic, ranging from the Gascogne Gulf to Morocco and the entire Mediterranean including Tyrrhenian, Ionian, Adriatic and Aegean basins ( Koukouras et al., 1992; Ziebis et al., 1996; d’Udekem d’Acoz, 1997; Abed-Navandi & Dworschak, 1997; Ngoc-Ho, 2003; Sakai, 2011, 2017); usually found burrowing in well sorted fine sand, rarely forming dense populations (Ziebis et al., 1996; d’Udekem d’Acoz, 1997). The presence of the species in the Black Sea is now confirmed.

Figures

FIGURE 1. Burrowing axiidean mud shrimps of the family Callianassidae from the north-eastern Black Sea, habitus (lateral view), live coloration and size comparison: Gilvossius candidus (Olivi, 1792) (a—♂, cl. 16.3 mm, ZMMU Ma-6193; b—ovigerous ♀, cl. 18.1 mm, ZMMU Ma 6195); Gilvossius tyrrhenus (Petagna, 1792) (c—♂, cl. 12.1 mm, ZMMU Ma 6197; d—ovigerous ♀, cl. 12.4 mm, ZMMU Ma 6199; Necallianassa truncata (Giard & Bonnier, 1890) (e—♂, cl. 9.8 mm, ZMMU Ma 6189; f—♂, cl. 8.9 mm, ZMMU Ma 6190; g—ovigerous ♀, cl. 9.6 mm, ZMMU Ma 6192).

FIGURE 4. Necallianassa truncata (Giard & Bonnier, 1890) from the north-eastern Black Sea (a–c—♂, cl. 9.8 mm, ZMMU Ma 6189; d—♂, cl. 8.9 mm, ZMMU Ma-6190; e, f—♀, cl. 9.2 mm, ZMMU Ma 6191): a, b, e—habitus (a, e—dorsal; b—lateral views); c—major PI (cheliped), internal view; d—chela of major PI, internal view; f—telson and uropods, dorsal view.