Platytyphlops taylorae Gerken 2018, n. sp.

Platytyphlops taylorae n. sp.

(Figs 65–67)

Type material. Holotype: ovigerous female, NMV J62274, 66 °2’54”–3’S, 49°49’24” E, 738–806 m, off Enderby Land, East Antarctica. Paratypes: ovigerous female, dissected, NMV J62275, 66 °2’54”–3’S, 49°49’24” E, 738– 806 m, off Enderby Land, East Antarctica; subadult male, dissected, NMV J54363, 66 °2’54”–3’S, 49°47’54”– 49°50’E, 690–911 m, off Enderby Land, East Antarctica, 29–30 November 1985.

Diagnosis. Carapace with 4 pairs of lateral ridges, covered in small pits, marginal carina entire, ridge present on pseudorostrum; eyelobe without lenses or tumidities. Antennule article 1 not expanded; accessory flagellum 1.0 main flagellum. Telson shorter than uropod peduncles, with 3 terminal setae, central seta less than half length of outer pair. Uropod endopod article 11.4 length of articles 2 and 3 together. Subadult male carapace without pits, dorsoventrally flattened relative to female. Telson as long as uropod peduncles, with 3 equal terminal setae

Description. Holotype ovigerous female, NMV J62274, paratype ovigerous female, NMV J62275.

Ovigerous female, holotype 7.6 mm, paratype 7.0 mm. Carapace covered with small pits, dorsoventrally flattened, dorsolateral posterior expansion, dorsal carina posterior 0.5 of carapace, 1 short posterior lateral ridge, 1 longer mid-lateral ridge, 1 short ridge from anterior margin on pseudorostral lobes; pseudorostral lobes 0.3 carapace length; eyelobe 0.1 carapace length; carapace 1.2 length of pereonites together (Fig. 65 A–B).

Paratype ovigerous female, NMV J62275, 7.0 mm.

Antennule peduncle article 1 longest, surface scaled, 1 pedunculate and 4 simple setae; article 2 0.75 article 1 length, with 4 simple setae; article 3 0.7 article 2 length, with 4 simple setae; main flagellum of 4 articles, with simple setae and 2 aesthetascs terminally; accessory flagellum of 3 articles, equal to main flagellum, with simple setae (Fig. 65C).

Antenna of 4 articles; article 1 with 1 pappose seta; article 2 unarmed; article 3 margin serrate, with 1 pappose and 2 simple setae; article 4 1.6 article 3 length, with 2 pedunculate and 2 simple setae terminally (Fig. 65D).

Mandible navicular, with 8 microserrate setae medially, lacinia mobilis with 4 cusps (Fig. 65E).

Maxillule with 2 endites; outer endite with 9 stout setae; inner endite with 3 simple and 1 dentate setae; palp with 2 setae (Fig. 65F).

Maxilla with 3 endites; broad endite distal margin with pappose and simple setae, medial margin with row of simple setae; medial narrow endite with 4 simple setae terminally; distal narrow endite with 5 simple setae terminally; both narrow endites extending past distal margin of broad endite (Fig. 65G).

Maxilliped 1 basis produced distally as broad lobe, distal margin of lobe with pappose and dentate setae, medial margin with microserrate and pappose setae; ischium absent; merus with 2 pappose setae medially, 1 pappose seta laterally; carpus 2.5 merus length, medial face with pappose and comb setae, 1 pappose seta laterally; propodus 0.7 carpus length, with 2 plumose and 5 simple setae distally; dactylus 0.4 propodus length, with 4 simple setae terminally (Fig. 65H).

Maxilliped 2 basis 1.0 all other articles together, 6 pappose setae distally; ischium 0.1 basis length, unarmed; merus 1.7 ischium length, with 2 pappose setae medially and 1 pappose seta laterally; carpus 2.0 merus length, with 10 plumose setae medially and 1 pappose seta laterally; propodus 0.5 carpus length, with plumose setae; dactylus 0.8 propodus length, with 3 simple setae terminally (Fig. 65I).

Maxilliped 3 basis 1.2 all other articles together, with 4 pappose setae medially, 5 plumose setae laterally, not expanded; ischium 0.05 basis length, unarmed; merus 1.5 ischium length, with 2 pappose setae medially, 1 pappose seta laterally; carpus 4.3 merus length, with 16 plumose setae medially, 2 plumose setae laterally; propodus 0.6 carpus length, with plumose setae; dactylus 0.5 propodus length, with 5 simple setae terminally; exopod as long as basis, basal article with 9 plumose setae, flagellum with plumo-annulate setae (Fig. 66A).

Pereopod 1 broken.

Pereopod 2 basis longer than next 4 articles together, with 8 plumose and 11 simple setae; ischium 0.06 basis length, unarmed; merus 3.5 ischium length, with 3 plumose and 1 simple setae, 1 microserrate seta with single subterminal setule; carpus 2.6 merus length, with 8 microserrate setae with single subterminal setule, 1 plumose seta; propodus 0.2 carpus length, with 2 simple and 1 microserrate seta with single subterminal setule; dactylus 3.25 propodus length, with 3 microserrate setae with single subterminal setule, 4 simple setae, terminal seta broken; exopod shorter than basis, basal article with 7 plumose setae, flagellum with plumo-annulate setae (Fig. 66B).

Pereopod 3 broken.

Pereopod 4 basis 2.8 all other articles together, with 11 plumose setae; ischium 0.02 basis length, unarmed; merus 6.0 ischium length, with 1 simple seta; carpus 0.7 merus length, with 1 simple and 2 annulate setae; propodus equal to carpus length, with 1 annulate seta; dactylus 0.5 propodus length, with 2 simple setae terminally; exopod rudimentary, 0.1 basis length, of 2 articles with simple setae (Fig. 66C).

Pereopod 5 basis 1.2 all other articles together, with 1 simple and 8 plumose setae; ischium 0.1 basis length, with 1 simple and 1 microserrate setae; merus 2.0 ischium length, with 1 annulate seta; carpus equal to merus length, with 2 simple and 2 annulate setae; propodus 0.5 carpus length, with 1 annulate seta; dactylus 0.5 propodus length, with 3 simple setae terminally (Fig. 661D).

Telson 2.4 length of pleonite 6, with 4 setae with single subterminal setule laterally, 3 terminal setae, central seta short and microserrate, outer setae simple (Fig. 66E).

Uropod peduncles 2.7 pleonite 6 length, 1.1 telson length, with 16–17 setae with single subterminal setule medially. Uropod endopod of 3 articles, 1.1 peduncle length; article 1 longer than articles 2 and 3 together, with 10 setae with single subterminal setule medially; article 2 0.5 article 1 length, with 4 setae with single subterminal setule medially, 1 setae with single subterminal setule laterally; article 3 0.6 article 2 length, with 1 lateral and 1 medial setae with single subterminal setule, terminal seta with single subterminal setule, equal to article 3 length. Uropod exopod 0.8 length of endopod; article 1 0.2 length of article 2, with 1 simple seta; article 2 with 7 simple setae medially, 8–9 simple setae laterally, 1 seta with single subterminal setule laterally, simple terminal seta 0.6 article 2 length (Fig. 66E).

Paratype subadult male, NMV J54363.

Subadult male, 8.5 mm. Carapace as in female (Fig. 67A).

Antennule peduncle article 1 as long as articles 2 and 3 together, surface scaled, unarmed; article 2 0.7 article 1 length, with 1 simple seta; article 3 0.7 article 2 length, with 5 simple setae; main flagellum of 5 articles, with simple setae and 2 aesthetascs terminally; accessory flagellum of 4 articles, equal to main flagellum length, with simple setae (Fig. 67B).

Pereopod 1 basis longer than next 3 articles together, with 15 plumose setae, margins serrate; ischium 0.07 basis length, with 1 plumose seta; merus 4.7 ischium length, with 5 plumose setae, margin serrate; carpus 1.3 merus length, with 4 plumose setae; propodus 1.2 carpus length, with 6 simple setae; dactylus 0.8 propodus length, with 9 simple setae, 1 simple seta terminally; exopod as long as basis, basal article with 4 pappose setae, flagellum with plumo-annulate setae (Fig. 67C).

Pereopod 2 basis longer than next 4 articles together, with 7 plumose setae, margins serrate; ischium 0.06 basis length, with 1 microserrate seta with single subterminal setule; merus 3.0 ischium length, with 1 microserrate seta with single subterminal setule and 1 plumose seta; carpus 2.8 merus length, with 5 microserrate setae with single subterminal setule, 1 plumose seta; propodus 0.3 carpus length, with simple seta; dactylus 2.6 propodus length, with 6 simple setae, 1 simple seta terminally; exopod shorter than basis, basal article with 4 pappose setae, flagellum with plumo-annulate setae (Fig. 67D).

Telson 4.2 length of pleonite 6, lateral margins serrate, with 6–8 simple setae with single subterminal setule laterally, 3 simple terminal setae, longer than lateral setae (Fig. 67F).

Uropod peduncles 4.1 pleonite 6 length, equal to telson length, with 15 simple setae with single subterminal setule medially. Uropod endopod of 3 articles, 1.1 peduncle length; article 1 1.9 articles 2 and 3 together, with 15 simple setae with single subterminal setule medially; article 2 0.3 article 1 length, with 4 simple setae with single subterminal setule medially; article 3 0.9 article 2 length, with 3 medial and 1 lateral simple setae with single subterminal setule, terminal seta simple with single subterminal setule, 0.7 article 3 length. Uropod exopod 0.9 length of endopod; article 1 0.2 article 2 length; article 2 with 6 medial and 5 lateral simple setae with single subterminal setule, terminal seta broken (Fig. 67F).

Etymology. The species is named taylorae in honor of Dr. Joanne Taylor, Manager of the Natural Science Collections, Museums Victoria, Melbourne, Australia, for her contributions to peracarid systematics, hospitality and help with loans and collection information.

Depth. 690–1264 m.

Distribution. Tasmania, East Antarctica, 41°– 66° S, 29°– 148° E.

Remarks. The carapace of Platytyphlops taylorae is sculptured with many ridges, and can be differentiated from the other sculptured species by the pleon being relatively short, shorter than the carapace and pereonites together. In addition, the carapace is covered in small pits.