Acanthephyra acutifrons Spence Bate, 1888

Alves-Júnior, Flavio De Almeida, Silva, Elinai Dos Santos, Araújo, Marina De Sá Leitão Câmara De, Cardoso, Irene, Bertrand, Arnaud & Souza-Filho, Jesser F., 2019, Taxonomy of deep-sea shrimps of the Superfamily Oplophoroidea Dana 1852 (Decapoda: Caridea) from Southwestern Atlantic, Zootaxa 4613 (3), pp. 401-442 : 403

Species Acanthephyra acutifrons Spence Bate, 1888

( Figs. 1 A–B, 2 , 39 A)

Acanthephyra acutifrons Spence Bate, 1888: 749 , pl. 126: fig. 3.— Chace 1940: 146, fig. 23; 1986: 10, figs 2b, 4b, 5b.—Crosnier 1987a: 696.— Kensley et al. 1987: 283.— Cardoso & Young 2005: 8 , figs. 3 a–d; 4 a–g; 5 a–d, 6a.— Pequegnat & Wicksten 2006: 95.— Judkins 2014: 304.

Material examined: 1 OF, Pernambuco, Abracos 2 ST#12, Midwater, 50 m, 08° 29,74’ S / - 34° 44,59’ W; 08° 29,74’ S / 034° 45’ W, 13 April 2017, MOUFPE 18.421. 1 M, 1 F and 1 OF, Pernambuco, Abracos 2 ST# 16/ Leg. 1, Micronekton Tow , 680 m, 07° 36,25’ S / 033° 59,50’ W, 14 April 2017, MOUFPE : 18.415. 4 M and 3 F, Rocas Atoll, Abracos 1 ST# 21/ Leg. 1, Midwater Tow , 115 m, 03° 39’ S / 033° 41’ W; 03° 38’ S / 033° 42’ W, 0 8 October 2015, MOUFPE : 15.596. 1 M and 1 F, Rocas Atoll, Abracos 1 ST# 22/ Leg. 1, Midwater Tow , 525 m, 04° 07’ S / 033° 47’ W; 04° 07’ S / 033° 48’ W, 0 8 October 2015, MOUFPE : 15.575. 2 M and 1 F, Rio Grande do Norte, Abracos 2 ST# 35/ Leg. 2, Midwater Tow , 1150 m, 04° 19,60’ S / 035° 29,86’ W; 04° 18,54’ S / 035° 32,40 W, 24 April 2017, MOUFPE : 18.414. 3 M and 2 F, Fernando de Noronha, Abracos 2 ST#39, Midwater Tow , 800 m, 04° 52,42’ S / 034° 3,51’ W; 04° 50,86’ S / 034° 5,11’ W, 24 April 217, MOUFPE : 18.424. 2 F, Pernambuco, Abracos 1 ST# 51/ Leg. 1, Midwater Tow , 800 m, 08° 56’ S / 034° 29’ W; 08/ 59’ S/ 034° 28’ W, 19 October 2015, MOUFPE : 15.593. 1 F, Rocas Atoll, Abracos 2 ST# 53A/ Leg. 2, Midwater Tow , 610 m, 03° 48,99’ S / 033° 59,27’ W; 03° 50,05’ S / 033° 58,74 W, 0 2 May 2017, MOUFPE : 18.416. 5 M, 6 F and 2 OF, Ceará Chain, Abracos 2 ST# 54B/ Leg. 2, Midwater Tow , 830 m, 03° 46,26’ S / 034° 43,64’ W; 03° 47 ‘ S / 034° 43,72 ‘W, 0 3 May 2017, MOUFPE : 18.411.

Diagnosis: Carapace with rostrum short, reaching 2/3 of scaphocerite, present between 6–8 dorsal teeth, ventral margin with one tooth; antennal spine absent; branchiostegal spine present, without distinct carina. Abdomen dorsally carinate on all somites; somites 3–6 with posteromesial tooth; the one of somite 3 distinctly strong. Male pleopod 1 with endopod rounded, lateral margins with densely plumose setae, distal lobe with numerous spines on distal portion. Male pleopod 2 appendix interna, about 3/4 as long as appendix masculina, with numerous densely plumose setae on lateral margins, distal portion slightly triangular, with hook setae. Appendix masculina with strong acute simple setae on distal and lateral margins (modified from Cardoso & Young 2005).

Distribution: Western Atlantic: Mexico (Gulf of Mexico), Cuba, Bahamas, Tortuga Island (11°30΄ N, 65°19΄ W; 11°37΄ N, 65°32΄ W), off Guiana (8°58΄ N, 57°40΄ W), off Suriname (9°05΄ N, 55°17΄ W), off French Guiana (9°03΄ N, 49°16΄ W), Brazil: (Rio Grande do Norte, Rocas Atoll, Pernambuco, Fernando de Noronha, off Alagoas (10°20΄ S, 30°32΄ W), Bahia and Espírito Santo); Meso Atlantic Ridge (1°20΄ S, 27°37΄ W), off Sahara Occidental (26°33΄ N, 21°27΄ W). Indo-Pacific Oceans: West Indian Ocean, Madagascar, Philippines, Indonesia (Sumatra), Australia, Philippines, Japan ( Chace 1940, 1986; Crosnier 1987; Kensley et al. 1987; Cardoso & Young 2005; Pequegnat & Wicksten 2006; Cardoso et al. 2014; Judkins 2014) ( Fig. 2 ).

Bathymetric distribution: 650–4200 m depth ( Chace 1986; Crosnier 1987; Kensley et al. 1987; Cardoso & Young 2005; Pequegnat & Wicksten 2006; Burghart et al. 2007; 2017) herein this species was found in Rocas Atoll at depths between 50–830 m, thus extending its bathymetric distribution to shallow waters.

Remarks: The material analysed here fits well with all diagnostic characters described by Spence Bate (1888), Chace (1940, 1986) and Cardoso & Young (2005). However, some variations in the number of dorsolateral spines on the telson were found. In the original description, Spence Bate (1888) described 3 pairs of dorsolateral spines in all specimens. Chace (1940, 1986) described specimens with 3 or 4 dorsolateral spines. Cardoso & Young (2005), based on material collected from Revizee Program between Bahia to Espírito Santo, verified the presence of six pairs of dorsolateral spines on telson, only 1 specimen had 7 spines on right side. In the present study, the specimens had 6 pairs of spines on telson ( Fig. 1B ) in accordance with Cardoso & Young (2005). The closest species to Acanthephyra acutifrons is A. curtirostris Wood-Mason & Alcock (1891) . The main differences between the two species are the presence of a dorsal carina on the first abdominal somite in A. acutifrons , absent in A. curtirostris ; and a long carina associated to branchiostegal spine in A. curtirostris , absent or reduced in A. acutifrons . Besides that A. acutifrons presents 6–8 dorsal teeth and the ventral tooth is slender ( Fig. 1A ) while A. curtirostris presents 10–14 dorsal teeth on rostrum ( Fig. 3A ), and the ventral tooth is robust. Acanthephyra acutifrons presents cosmopolitan distribution, occurring throughout the Indian, Pacific and Atlantic oceans ( Fig. 2 ), in meso- and bathypelagic zones (650–4200 m depth). The first record for this species in Brazilian waters was made by Cardoso & Young (2005) in the Campos Basin between the States of Bahia and Espírito Santo. In this paper, A. acutifrons is reported for the first time around an oceanic island (Rocas Atoll) and for the second time in Brazilian waters.

Figures

FIGURE 2. Global geographic distribution of Acanthephyra acutifrons Spence Bate, 1888. Black circles = previous records; star = new record.

FIGURE 3. Acanthephyra curtirostris Wood-Mason & Alcock, 1891. A. Ovigerous Female, lateral view. B. Telson, dorsal view (MOUFPE: 18.471). Scale bar = 1 cm.

FIGURE 39. Deep-sea shrimps of the family Acanthephyridae Spence Bate, 1888 being: A. Acanthephyra acutifrons Spence Bate, 1888 (MOUFPE: 18.424). B. Acanthephyra curtirostris Wood-Mason & Alcock, 1891 (MUFPE: 18.471). C. Acanthephyra eximia Smith, 1884 (MOUFPE: 15.685). D. Acanthephyra kingsleyi Spence Bate, 1888 (MOUFPE: 18.461). E. Acanthephyra quadrispinosa Kemp, 1939 (MOUFPE: 15.589). F. Acanthephyra stylorostratis (Spence Bate, 1888) (MOUFPE: 15.671), with all material collected in Northwestern Brazil.

FIGURE 1. Acanthephyra acutifrons Spence Bate, 1888. A. Female, lateral view. B. Telson, dorsal view (MOUFPE: 18.424). Scale bar = 1 cm.