Boreomysis

Daneliya, Mikhail E., 2023, Mysid Subfamily Boreomysinae (Crustacea: Mysida: Mysidae) in the Southeast Australian Deep-sea, Records of the Australian Museum (Rec. Aust. Mus.) 75 (2), pp. 87-124 : 92

Key to the subgenera of the genus Boreomysis

1 Anterior margin of carapace with distinct rostrum and large ventrolateral projections ( Figs 1A,B ; 4A,D ; 5A,B ). Pereopod propodus 2-segmented (except in B. dubia Coifmann, 1937 ) ( Figs 2I , 3D , 4L , 6C ) ............................................................................ Boreomysis sensu stricto

—— Anterior margin of carapace without distinct rostral projection, angular, apically blunt or rounded, with rather small, barely established ventrolateral projections ( Fig. 8A–C ). Pereopod propodus 1-segmented ( Fig. 9M ) ...................................................... Petryashovia subgen. nov.

Figures

Figure 1. Boreomysis (Boreomysis) inopinata sp. nov., holotype, male, 31 mm, AM P.106632. (A) habitus, lateral; (B) head, dorsal; (C) posterior part of body, dorsal;(D) posterior part of telson, dorsal; (E) posterior margin of abdomen, lateral; (F) posteriormargin of abdomen and proximal part of uropod (left side), ventral; (G) eye cornea, frontal; (H) antennular peduncle, medial; (I) male process of antennula, posterior; (J) antennal peduncle and scale, posterior; (K) distal part of antennal scale; (L) distolateral spine of antennal scale; (M) antennal peduncle, lateral; (N) uropod, ventral. Scales (mm):A, B = 10.0; C, E, F, N = 1.0; D, H, I, K, L (same scale as for K) = 0.5; G, J, M = 0.25.

Figure 2. Boreomysis (Boreomysis) inopinata sp. nov., holotype, male, 31 mm, AM P.106632. (A) labrum, ventral; (B) right mandible, ventral; (C) left mandible, ventral; (D) right lacinia mobilis, ventral; (E) mandibular palp, posterior; (F) maxilla 1, posterior; (G) maxilla 2, posterior; (H) maxilliped 1 endopod, posterior; (I) pereopod 1 (with flexor muscle of dactylus in propodus), posterior; (J) serrated seta of pereopod 1 carpus; (K) penis, lateral. Scales (mm):A–C, E–I, K = 1.0; D = 0.1; J = 0.25.

Figure 3. Boreomysis (Boreomysis) inopinata sp. nov. (A–I) holotype, male, 31 mm, AM P.106632; (J) paratype, female, 32 mm, AM P.106633. (A) maxilliped 2 endopod, posterior; (B, C) serrated setae of maxilliped 2 carpopropodus; (D) pereopod 5 endopod (with flexor muscle of dactylus in propodus), posterior; (E) pleopod 1, posterior; (F) pleopod 2, posterior; (G) pleopod 3, posterior; (H) pleopod 4, posterior; (I) pleopod 5 (also showing endopod muscles), anterior; (J) pleopod 5, posterior. Scales (mm):A, D–J = 1.0; B, C = 0.25.

Figure 4. Boreomysis (Boreomysis) sibogae. (A, D–G, I–K) female,31 mm, Tasmania,AMP.101174;(B) subadult male, New South Wales, AM P.106643; (C) juvenile, New South Wales,AM P.106640; (H) subadult male, New South Wales,AM P.106642. (A) head, lateral; (B) rostrum and eyes, lateral; (C) rostrum and eyes, lateral; (D) head, dorsal; (E) posterior margin of abdomen, lateral; (F) posterior margin of abdomen and telson (lateral spiniform setae not shown), dorsal; (G) posterior part of telson; (H) telson; (I) antennal scale; (J) uropodal endopod, ventral; (K) uropodal exopod (most of setae not shown); (L) pereopod 1 endopod, posterior. Scales (mm): 1.0.

Figure 5. Boreomysis (Boreomysis) sphaerops. (A–F, H–N) subadult female, New South Wales, AM P.106636; (G) subadult male, New South Wales,AM P.106637. (A) head, dorsal (antennal scale spine missing); (B) head, lateral; (C) posterior part of abdomen with telson and uropods (setae not shown), dorsal;(D) posterior margin of abdomen,lateral;(E) posterior part of telson;(F) antennal scale (distolateral spine missing); (G) distal part of antennal scale; (H) labrum,ventral;(I) mandibular palp, posterior;(J) left mandible, ventral; (K) right mandible, dorsal; (L) pars centralis of right mandible; (M) maxilla 1, posterior; (N) maxilla 2, posterior. Scales (mm):A–K, M, N = 1.0; L = 0.25.

Figure 6. Boreomysis (Boreomysis) sphaerops, subadult female, New South Wales, AM P.106636. (A) maxilliped 1 endopod, posterior; (B) maxilliped 2, anterior; (C) pereopod 1 endopod, anterior. Scales (mm): 1.0.

Figure 8. Boreomysis (Petryashovia) urospina sp. nov. (A, C, E–H, J, K) holotype, male, 33 mm,AM P.106628; (B, D, I) allotype, female, 40 mm, AM P.106629. (A, B) head, dorsal; (C) head, lateral; (D) head (carapace not shown), lateral; (E) posterior part of abdomen with telson and uropods (setae and spiniform setae mostly not shown), dorsal; (F) posterior margin of abdomen and proximal part of uropod (left side), ventral; (G) posterior margin of abdomen, lateral; (H) telson; (I) posterior part of telson; (J) antenna 2, ventral; (K) uropodal endopod, ventral. Scales (mm): 1.0.

Figure 9. Boreomysis (Petryashovia) urospina sp. nov., holotype, male, 33 mm, AM P.106628. (A) labrum, ventral; (B) mandibular palp, posterior; (C) right mandible, ventral; (D) left mandible, ventral; (E) maxilla 1, posterior; (F) maxilla 2, anterior; (G) maxilliped 1, anterior; (H) dactylar claw of maxilliped 1; (I) medial seta of maxilliped 1 basal endite; (J) maxilliped 2, anterior; (K) medial serrated seta of maxilliped 2 dactylus; (L) medial seta of maxilliped 2 carpopropodus; (M) pereopod 1 endopod, posterior; (N) pereopod 1 carpus, anterior; (O) medial setae of pereopod 1 merus; (P) medial seta of pereopod 1 carpus; (Q) paradactylary seta of pereopod 1; (R) penis, lateral. Scales (mm): A–G, J, M, N, R = 1.0; H, I, K, L, Q = 0.25; O, P = 0.5.