Phallolamprops pribilofensis Gerken 2018, n. sp.

Phallolamprops pribilofensis n. sp.

(Figs 46–49)

Type material. Holotype: ovigerous female, USNM 1274561, St. George, Pribilof Islands, Bering Sea, 73 m, October 1919. Paratypes: ovigerous female, dissected, USNM 1274562, collected with holotype; adult male, dissected, USNM 1274563, collected with holotype; adult male, USNM 1274564, collected with holotype.

Other material. Thirty ovigerous females, USNM 1274565, St. George, Pribilof Islands, 73 m, October 1919.

Diagnosis. Carapace without lateral ridges. Telson with 5 terminal setae, central seta shorter than outer pair, outer pair longer than inner pair inner pair. Adult male antennal flagellum extending past posterior border of pleonite 6. Telson with 5 setae, central seta long, other 4 seta short.

Description. Holotype ovigerous female, USNM 1274561; paratype ovigerous female, USNM 1274562.

Ovigerous female, 6.25 mm. Carapace with dorsal crest on anterior half, no other ornamentation; pseudorostral lobes 0.3 carapace lenth; eyelobe 0.04 carapace length; carapace equal to pereonites (Fig. 46A, B).

Antennule peduncle article 1 with 1 simple and 4 pedunculate setae; article 2 0.5 article 1 length, with 1 complex pedunculate and 2 simple setae; article 3 0.7 article 2 length, with 2 simple setae; main flagellum of 2 articles, with 3 simple setae and 1 aesthetasc; accessory flagellum of 2 articles, as long as article 1 of main flagellum, with 3 simple setae (Fig. 46C).

Antenna of 4 articles; article 1 with 2 plumose setae; article 2 with 2 plumose setae; article 3 with plumose seta; article 4 with 2 short simple setae terminally (Fig. 46D).

Mandible navicular, with 10 microserrate setae medially, lacinia mobilis with 2 cusps (Fig. 46E).

Maxillule with 2 endites; outer endite with 12 simple setae; inner endite with 1 simple and 3 microserrate setae; palp with 2 setae (Fig. 46F).

Maxilla with 3 endites; broad endite distal margin with simple and microserrate setae, medial margin with row of 17 microserrate setae, with microserrate seta behind row; medial narrow endite with 4 microserrate setae terminally; distal narrow endite with 5 microserrate setae terminally; both narrow endites extending past distal margin of broad endite (Fig. 46G).

Maxilliped 1 basis produced medially as broad lobe, with 4 simple and 2 microserrate setae distally, medial margin with 6 pappose setae, lateral margin with 3 plumose setae, basis lateral margin serrate; ischium absent; merus with simple seta; carpus 2.25 merus length, with 11 simple and 7 comb setae medially, 2 plumose setae laterally; propodus 0.7 carpus length, with 4 plumose and 5 simple setae; dactylus 0.4 propodus length, with 2 simple and 2 microserrate setae terminally (Fig. 46H).

Maxilliped 2 basis 1.3 all other articles together, with 2 plumose setae medially and 1 plumose and 1 simple setae laterally; ischium unarmed; merus equal to ischium, with plumose seta medially and pappose seta laterally; carpus 2.7 merus length, with 5 pappose and 4 simple setae medially, pappose seta laterally; propodus 0.7 carpus length, with 6 simple setae medially, 1 plumose and 1 simple setae laterally; dactylus 0.4 propodus length, with 3 simple and 1 micorserrate setae (Fig. 46I).

Maxilliped 3 basis 1.9 all other articles together, with 13 plumose setae medially, distolateral corner expanded, with 3 plumose setae; ischium 0.08 basis length, with simple seta; merus 1.4 ischium length, with simple seta medially, pappose seta laterally; carpus 1.4 merus length, with 6 pappose setae medially, pappose seta laterally; propodus 0.6 carpus length, with 3 pappose setae medially, 1 plumose and 1 pappose setae laterally; dactylus 0.7 propodus length, with 5 simple and 1 microserrate setae terminally; exopod 0.9 basis length, basal article with 3 pappose and 1 plumose setae, flagellum with plumo-annulate setae (Fig. 47A).

Pereopod 1 basis 1.1 all other articles together, with 20 plumose setae and 3 stout pappose setae medially; ischium 0.04 basis length, unarmed; merus 5.0 ischium length, with 2 plumose setae; carpus 1.3 merus length, with 4 simple and 1 pappose setae; propodus 0.9 carpus length, with 9 simple setae; dactylus 0.9 propodus length, with 7 simple setae and 6 simple setae terminally; exopod 0.8 basis length, basal article with 6 plumose setae, flagellum with plumo-annulate setae (Fig. 47B).

Pereopod 2 basis as long as next 4 articles together, with 9 plumose setae and simple seta with subterminal setule; ischium 0.06 basis length, unarmed; merus 4.0 ischium length, with simple seta with subterminal setule; carpus 2.1 merus length, with 8 setae with single subterminal setule; propodus 0.5 carpus length, with 2 setae with single subterminal setule; dactylus 0.9 propodus length, with seta with single subterminal setule and 1 annulate and 4 setae with single subterminal setule terminally; exopod 1.3 basis length, basal article with 4 plumose setae, flagellum with plumo-annulate setae (Fig. 47C).

Pereopod 3 basis 1.4 all other articles together, with 11 plumose setae; ischium 0.1 basis length, with 3 annulate and 2 plumose setae; merus 1.7 ischium length, with 4 annulate setae; carpus 0.9 merus length, with 5 annulate setae; propodus 0.6 carpus length, with 1 simple and 1 annulate setae; dactylus 0.6 propodus length, with 3 simple setae terminally; exopod rudimentary, 0.3 basis length, of 2 articles with 5 plumose setae (Fig. 47D).

Pereopod 4 basis as long as next 4 articles together, with 6 plumose setae; ischium 0.1 basis length, with 5 annulate setae; merus 2.5 ischium length, with 6 annulate and 1 simple setae; carpus 1.1 merus length, with 3 annulate and 1 simple setae; propodus 0.5 carpus length, with simple seta; dactylus 0.6 propodus length, with 2 simple setae terminally; exopod rudimentary, 0.4 basis length, of 2 articles with 1 simple and 4 plumose setae (Fig. 47E).

Pereopod 5 basis 0.6 all other articles together, with 1 simple and 6 plumose setae; ischium 0.2 basis length, with 5 annulate setae; merus 2.3 ischium length, with 5 annulate setae; carpus 1.3 merus length, with 2 simple, 1 plumose, and 5 annulate setae; propodus 0.3 carpus length, with annulate seta; dactylus 0.8 propodus length, with 3 simple setae terminally (Fig. 47F).

Telson 1.6 length of pleonite 6, with 4 lateral setae, 5 terminal setae, outermost pair with single subterminal setule (Fig. 47G).

Uropod peduncles 1.9 pleonite 6 length, 1.2 telson length. Uropod endopod of 3 articles, 0.9 peduncle length; article 1 longer than articles 2 and 3 together, with 8 setae with single subterminal setule medially; article 2 0.4 article 1 length, with 2 setae with single subterminal setule medially, 1 seta with single subterminal setule laterally; article 3 equal to article 2, with seta with single subterminal setule and simple seta medially, with simple seta laterally, terminal seta equal to article 3 length, with single subterminal setule. Uropod exopod 0.8 length of endopod; article 1 0.7 article 2 length, with 2 setae with single subterminal setule; article 2 1.3 article 1 length, with 4–6 setae with single subterminal setule, terminal seta equal to article 2 (Fig. 47G).

Paratype adult male, USNM 1274563.

Adult male, 8.2 mm. Carapace with dorsal crest, ventrally expanded to accommodate antenna; pseudorostral lobes 0.5 carapace length; eyelobe 0.1 carapace length; carapace equal to pereonites. Pair of tubular penial lobes present ventrally on pereonite 5, between pereiopods. Pleonite 1 with large ventral plate with lateral margins lined with complex plumose setae, posterior corners with hooked simple setae; pleonite 2 with 2 pairs hooked simple setae protruding from expansion; hooked setae holding antennal flagellum against pleonites (Fig. 48 A–C).

Antennule peduncle article 1 longer than articles 2 and 3 together, covered with scales, margin serrate, with simple seta; article 2 0.5 length of article 1, with 6 simple and 1 pedunculate setae; article 3 0.7 article 2 length, with 3 simple setae; main flagellum of 3 articles, as long as article 3, with 3 simple setae and 2 aesthetascs; accessory flagellum of 3 articles, 0.8 length of main flagellum, with 4 simple setae (Fig. 48D).

Antenna extending to end of pereon; penduncle of 5 articles, articles 1–3 with pappose seta, articles 4–5 with ranks of setae, not completely encircling articles; flagellum with short articles, each article with seta (Fig. 48 E–F).

Maxilliped 3 basis 1.8 all other articles together, with 6 plumose, 18 pappose and 1 simple setae; ischium 0.02 basis length, with pappose seta; merus 3.0 ischium length, with 2 pappose setae medially, plumose seta laterally; carpus 3.7 merus length, with 9 plumose and 6 simple setae medially, 1 simple and 1 plumose setae laterally, lateral margin serrate; propodus 0.5 carpus length, with 12 simple setae medially, 3 plumose and 1 simple setae laterally, lateral margin serrate; dactylus 0.4 propodus length, with 7 setae; exopod 0.9 basis length, basal article with 8 pappose setae, flagellum with plumo-annulate setae (Fig. 48G).

Pereopod 1 basis 1.4 all other articles together, with 28 pappose and 2 pappose–microserrate setae; ischium 0.02 basis length, unarmed; merus 3.0 ischium length, with 2 plumose setae medially, 2 plumose setae laterally; carpus 2.8 merus length, with 1 simple and 6 plumose setae medially, 2 plumose setae laterally; propodus 0.6 carpus length, with 4 simple setae medially, 1 simple and 1 plumose setae laterally; dactylus equal to propodus, with 12 simple setae; exopod 0.8 basis length, basal article with 10 pappose setae, flagellum with plumo-annulate setae (Fig. 49A).

Pereopod 2 basis 1.2 all other articles together, with 23 plumose and 1 pappose setae; ischium 0.04 basis length, unarmed; merus 4.0 ischium length, with 3 simple, 1 plumose, 1 pappose setae and seta with single subterminal setule; carpus 2.1 merus length, with 10 microserrate setae with subterminal setule, 2 pappose and 1 simple setae, margins serrate; propodus 0.3 carpus length, with 3 simple setae; dactylus 1.4 propodus length, with 4 microserrate setae with single subterminal setule, and 2 simple setae terminally; exopod 0.9 basis length, basal article with 10 plumose setae, flagellum with plumo-annulate setae (Fig. 49B).

Pereopod 3 basis 2.1 all other articles together, with 7 pappose and 5 plumose setae; ischium 0.07 basis length, with 1 plumose and 3 annulate setae; merus 2.0 ischium length, with 7 annulate setae; carpus equal to merus length, with 3 simple and 5 annulate setae; propodus 0.7 carpus length, with annulate seta; dactylus 0.5 propodus length, with 3 simple setae terminally; exopod 0.9 basis length, basal article with 9 pappose setae, flagellum with plumoannulate setae (Fig. 49C).

Pereopod 4 basis 1.4 all other articles together, with 9 plumose setae; ischium 0.07 basis length, with 3 annulate setae; merus 2.8 ischium length, with 4 simple and 3 annulate setae; carpus 1.1 merus length, with 1 plumose, 2 simple and 4 annulate setae; propodus 0.8 carpus length, with annulate seta; dactylus 0.6 propodus length, with 3 simple setae terminally; exopod 0.9 basis length, basal article with 7 plumose setae, flagellum with plumo-annulate setae (Fig. 49D).

Pereopod 5 basis 0.8 all other articles together, with 1 simple, 1 complex pedunculate and 5 pappose setae; ischium 0.1 basis length, with 4 annulate setae; merus 3.3 ischium length, with 4 simple and 5 annulate setae; carpus 1.1 merus length, with 1 simple, 1 plumose and 7 annulate setae; propodus 0.6 carpus length, with annulate seta; dactylus 0.6 propodus length, with 3 simple setae terminally (Fig. 49E).

Penial lobe 0.4 length of pereopod 5 basis, tubular (Fig. 62C, 49E).

Telson 2.3 length of pleonite 6, without lateral setae, 5 microserrate terminal setae, lateral margins serrate (Fig. 49F).

Uropod peduncles 3.1 pleonite 6 length, 1.3 telson length, with 17 microserrate setae medially. Uropod endopod of 3 articles, 0.9 peduncle length; article 1 longer than articles 2 and 3 together, with 16–17 microserrate setae medially; article 2 0.5 article 1 length, with 6–7 microserrate setae medially; article 3 0.5 article 2 length, with microserrate seta with single subterminal setule medially, 1 complex and 1 pedunculate setae laterally, terminal seta with subterminal setule 0.9 article 3 length. Uropod exopod equal to length of endopod; article 1 2.0 length of article 1, wth 5–6 simple setae medially, complex seta laterally; article 2 0.5 article 1 length, with 4 simple setae medially, 2 complex setae laterally, simple terminal seta 0.7 length of article 2 (Fig. 49F).

Etymology. The species is named pribilofensis for the locality of collection, St. George, one of the Pribilof Islands.

Depth. 70 m.

Distribution. Pribilof Islands, Bering Sea, 56°N, 169°W

Remarks. Female Phallolamprops californiensis can be distinguished from female P. pribilofensis by the pseudorostrum, which is blunt in side and dorsal views in the former, and pointed in side and dorsal views in the latter. Also, in P. californiensis the central and outer pair of setae are long, and the inner pair is very short, while in P. pribilofensis the terminal setae are much more equal in length. The adult males can be distinguished from each other by the form of the penial lobes and the ventral elaboration of pleonites 1 and 2. In P. californiensis the penial lobes are distinctly hooked, pointing anteriorly, while in P. pribilofensis the penial lobes are simple tubes and do not appear hooked. In P. californiensis the ventral structure on pleonite 1 has only two pairs of setae, while the ventral structure on pleonite 1 in P. pribilofensis has seven pairs of setae.