identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
CF49EC2A480257119CF9275091312ABE.text	CF49EC2A480257119CF9275091312ABE.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Haploniscus apaticus Knauber & Riehl 2025	<div><p>Haploniscus apaticus Knauber &amp; Riehl sp. nov.</p><p>Figs 6, 7, 8, 9, 26</p><p>Holotype.</p><p>SKB Hap 08, adult male (stage VI), 3.3 mm, MIMB 50307.</p><p>Paratypes.</p><p>SKB Hap 18, adult female (stage IV), 3.2 mm, MIMB 50308;  SKB Hap 48, adult female (stage IV; genome), SMF 56565 .</p><p>Type locality.</p><p>St. LV 71–04 – 10, RV “ Akademik M. A. Lavrentyev ”, SokhoBio expedition, EBS, 3366 m, 47°12.2'N, 149°36.7'E, Northwest Pacific, Sea of Okhotsk, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=149.61166&amp;materialsCitation.latitude=47.203335" title="Search Plazi for locations around (long 149.61166/lat 47.203335)">Kuril Basin</a>.</p><p>Further records.</p><p>St. LV 71–02 – 07: SKB Hap 27 (manca) SMF 56544, SKB Hap 36 (manca) MIMB 50309; St. LV 71–04 – 09: SKB Hap 55 (manca) MIMB 50310, SKB Hap 62 (adult male) SMF 56579; St. LV 71–10 – 07: SKB Hap 02 (adult female) SMF 56519.</p><p>Distribution.</p><p>Northwest Pacific, Sea of Okhotsk, Kuril Basin, depth 3351–3366 m. Visualized in Fig. 27.</p><p>Etymology.</p><p>“  apaticus ” is a Latinized adjective derived from “ Apate ”, the goddess of deceit in Greek mythology. This name refers to this species’ lack of a pronounced sexual dimorphism, e. g., in the pleotelson shape, and overall inconspicuous morphology, keeping it hidden amongst its sibling species until recently.  Haploniscus apaticus can be interpreted in English as “ deceitful or deceptive  Haploniscus . ”</p><p>Synonymy.</p><p>Haploniscus SO - SO (see Knauber et al. 2022).</p><p>Diagnosis.</p><p>Differs from other species of the  belyaevi - complex in the following characters: Prn 4 lateral margin longer than Prn 5 lateral margin; Plt posterolateral processes straight, oriented posterolaterally; PV – VII lengths distinctly exceeding PI – IV lengths.</p><p>Molecular diagnosis.</p><p>differing in the COI gene from other species of the  belyaevi - complex in the nucleotides T (position 69 of the alignment), A (220), A (364), G (412), G (469), A (475), and C (556).</p><p>Description.</p><p>Male. Body (Fig. 6 B) length 2.5 width; oval; anterior body length (Ceph – Prn 4) 1.0 posterior body length (Prn 5 – Plt); lateral margin interrupted between Prn 7 and Plt, otherwise continuous.</p><p>Cephalothorax (Fig. 6 B, D) length 0.41 width, 0.10 body length, width 0.59 body width; frontal margin width 0.48 Ceph width; rostrum curved upwards.</p><p>Pereonite 1 (Fig. 6 B) posterior tergite margin through Prn 5 anterior tergite margin delicately serrated, setose; Prn 2–5 anterolateral angles slightly projecting; Prn 1–4 posterolateral angles slightly projecting; Prn 4 lateral margin length 1.17 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 6 B, 26 J) length 0.79 width, 0.25 body length, trapezoidal, posterior margin rounded, convex; tergite surface smooth; with posterolateral tergal ridge between uropod insertion and posterolateral process; posterolateral processes short, 0.35 Plt length, straight, oriented posterolaterally.</p><p>Antenna I (Fig. 7 E) length 0.16 body length; flagellum with 5 articles.</p><p>Antenna II (Fig. 7 A) length 0.69 body length; article 3 dorsal projection triangular, projection length 0.38 article 3 length; article 5 projection length 0.43 article 5 length; flagellum with 19 articles.</p><p>Mandible (Fig. 8 B, C) incisor with 5 cusps, left Md lacinia mobilis with 4 cusps.</p><p>Maxillipeds (Fig. 8 A) left Mxp with 4 coupling hooks; right Mxp with 3 coupling hooks.</p><p>Pereopod II (Fig. 7 C) length 0.34 body length. PIII length 0.35 body length. PIV length 0.37 body length. PV length 0.64 body length. PVI (Fig. 7 D) length 0.68 body length. PVII length 0.62 body length; PV – VII lengths distinctly exceeding PI – IV lengths, PVII shorter than PVI.</p><p>Pleopod I (Figs 9 A, 26 J) medial lobes subtriangular, projecting caudolaterally; adjoining at the apex.</p><p>Pleopod II (Fig. 9 B, C) protopod semi-circular, with distal lobe extending beyond protopod distal margin; endopod stylet 1.8 protopod length.</p><p>Female. Differs from male in the following characters:</p><p>Body (Fig. 6 A) length 2.4 width; anterior body length (Ceph – Prn 4) 0.95 posterior body length (Prn 5 – Plt).</p><p>Cephalothorax (Fig. 6 A, C) length 0.26 width, 0.07 body length, width 0.60 body width; frontal margin width 0.51 Ceph width.</p><p>Pereonite 4 (Fig. 6 A) lateral margin length 1.24 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 6 A, 26 I) length 0.81 width, 0.25 body length; posterolateral processes 0.32 Plt length.</p><p>Antenna I (Fig. 6 A) length 0.14 body length; flagellum with 4 articles.</p><p>Antenna II (Fig. 6 A) length 0.63 body length; flagellum with 16 articles.</p><p>Operculum (Fig. 26 I) length 0.97 width, 0.81 Plt length; distal margin with numerous, evenly distributed long setae; lateral margins with fewer, evenly distributed short setae.</p></div>	https://treatment.plazi.org/id/CF49EC2A480257119CF9275091312ABE	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Knauber, Henry;Schell, Tilman;Brandt, Angelika;Riehl, Torben	Knauber, Henry, Schell, Tilman, Brandt, Angelika, Riehl, Torben (2025): Across trench and ridge: description of five new species of the Haploniscus belyaevi Birstein, 1963 species complex (Isopoda, Haploniscidae) from the Kuril-Kamchatka Trench region. Zoosystematics and Evolution 101 (2): 813-853, DOI: 10.3897/zse.101.137663
BC04A7E2765F554B8A48FEB397DB12D1.text	BC04A7E2765F554B8A48FEB397DB12D1.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Haploniscus belyaevi Birstein 1963	<div><p>Haploniscus belyaevi Birstein, 1963</p><p>Figs 1, 2, 3, 4, 5, 26</p><p>Neotype.</p><p>SKB Hap 46, adult male (stage VI), 3.4 mm, MIMB 50300.</p><p>Paraneotypes.</p><p>SKB Hap 04, adult female (stage IV; genome), SMF 56521;  SKB Hap 24, adult female (stage IV), 3.2 mm, MIMB 50294;  SKB Hap 06, adult male (stage VI), 3.6 mm, SMF 56523 .</p><p>Type material.</p><p>As pointed out by Knauber et al. (2022), the original male syntype of  H. belyaevi as depicted in the original species description was lost. Instead, the species’ type material is lumped together with additional material of  Haploniscus menziesi Birstein, 1963 . Most specimens are in poor condition, lacking either the distal AII with the characteristic spine on the fifth peduncular article or the pleotelson, rendering identification beyond genus level difficult. Three specimens can be identified as members of the  belyaevi - complex, yet, as all of them are (ovigerous) female stages, allocation to one of the herein described member species of the  belyaevi - complex remains uncertain. The type material is missing associated information about the sampling locality, and as the original description by Birstein does not define a type locality,  H. belyaevi does not possess a definite type locality.</p><p>Based on I) the lack of a definite type locality, II) the presence of multiple haploniscid species in the type material of  H. belyaevi, III) the absence of the original male syntype, and IV) uncertainty about where the material at hand stems from and whether it represents the type material,  H. belyaevi is considered a nomen dubium. In an attempt to resolve the taxonomic identity of  H. belyaevi, the species is therefore defined by the illustrations depicted in the original description by Birstein (1963), and a male neotype alongside additional paratypes were assigned from recent material of the SokhoBio expedition (compare H. SO - KIR from Knauber et al. 2022), which exhibit a strong morphological resemblance to  H. belyaevi as featured in the original description. This goes alongside the designation of a type locality, which is in the vicinity of a “ Vityaz ” station, where  H. belyaevi was historically sampled.</p><p>Type locality.</p><p>LV 71–09 – 07, RV “ Akademik M. A. Lavrentyev ”, SokhoBio expedition, EBS, 3374 m, 46°12.2'N, 152°03.1'E, Northwest Pacific, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=152.05167&amp;materialsCitation.latitude=46.203335" title="Search Plazi for locations around (long 152.05167/lat 46.203335)">abyssal branch of the Kuril-Kamchatka Trench into the Bussol Strait</a>.</p><p>Further records.</p><p>St. LV 71–01 – 08: SKB Hap 25 (manca) MIMB 50295; St. LV 71–04 – 09: SKB Hap 39 (manca) SMF 56556, SKB Hap 42 (manca) MIMB 50297, SKB Hap 43 (manca) MIMB 50298, SKB Hap 60 (adult female) MIMB 50305, SKB Hap 61 (adult female) MIMB 50306; St. LV 71–04 – 10: SKB Hap 07 (adult male) SMF 56524, SKB Hap 17 (adult female) SMF 56534, SKB Hap 38 (manca) SMF 56555; St. LV 71–07 – 03: SKB Hap 12 (manca) SMF 56529, SKB Hap 19 (adult male) SMF 56536, SKB Hap 20 (manca) MIMB 50293, SKB Hap 56 (adult male) MIMB 50302, SKB Hap 57 (adult female) SMF 56574, SKB Hap 58 (adult male) MIMB 50303, SKB Hap 59 (adult male) MIMB 50304; St. LV 71–07 – 04: SKB Hap 03 (adult female) MIMB 50292, SKB Hap 40 (adult female) MIMB 50296, SKB Hap 41 (adult female) SMF 56558, SKB Hap 44 (manca) MIMB 50299, SKB Hap 45 (manca) SMF 56562; St. LV 71–09 – 06: SKB Hap 15 (manca) SMF 56532, SKB Hap 23 (adult female) SMF 56540; St. LV 71–09 – 07: SKB Hap 05 (adult male) SMF 56522, SKB Hap 16 (manca) SMF 56533, SKB Hap 32 (adult male) SMF 56549, SKB Hap 33 (manca) SMF 56550, SKB Hap 47 (adult male) MIMB 50301.</p><p>Distribution.</p><p>Northwest Pacific, Sea of Okhotsk, Kuril Basin, and abyssal regions to the northwest of the Kuril-Kamchatka Trench, depth 3299–3386 m. Given its occurrence on both sides of the Kuril Island Ridge, it might be possible that this species’ lowest bathymetric limit might lie even shallower, as it most likely dispersed across the Bussol Strait in one or other direction with a maximum depth of 2,350 m. The original species description of  H. belyaevi depicts a distributional range extending far into the KKT area, yet despite sampling these areas during the above-mentioned expeditions,  H. belyaevi was solely recorded in the vicinity of the Bussol Strait. One can therefore only hypothesize that Birstein, potentially due to limited material, lumped the distributional patterns of multiple  belyaevi - complex members together, not realizing that he was dealing with multiple species. Visualized in Fig. 27.</p><p>Synonymy.</p><p>Haploniscus SO - KIR (see Knauber et al. 2022).</p><p>Diagnosis.</p><p>The species differs from other members of the  belyaevi - complex in the following characters: rostrum curved upwards, anteriorly flat; Prn 1 anterior tergite margin delicately serrated, setose; Prn 1 anterolateral angles with minute acute projection; posterolateral processes short, more than 0.10 Plt length, curved in males, oriented posteriorly.</p><p>Molecular diagnosis.</p><p>Differing in the 16 S gene from other species of the  belyaevi - complex in the nucleotide C (position 249 of the alignment) as well as the nucleotides G (199), C (334), T (376), C (409), A (412), and G (592) of the COI gene.</p><p>Description.</p><p>Male. Body (Figs 1 B, 2 B) length 2.3 width; subrectangular; anterior body length (Ceph – Prn 4) 1.0 posterior body length (Prn 5 – Plt); lateral margin interrupted between Prn 7 and Plt, otherwise continuous.</p><p>Cephalothorax (Figs 1 B, 2 B, D) length 0.38 width, 0.10 body length, width 0.58 body width; frontal margin width 0.50 Ceph width; rostrum curved upwards, frontally plane.</p><p>Pereonite 1 (Figs 1 B, 2 B) anterior tergite margin through Prn 5 anterior tergite margin delicately serrated, setose; Prn 1–5 anterolateral angles slightly projecting; Prn 1–4 posterolateral angles slightly projecting; Prn 4 lateral margin length 1.04 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 1 B, 2 B, 26 H) length 0.74 width, 0.25 body length, rectangular, posterior margin rounded, convex; tergite surface smooth; with posterolateral tergal ridge between uropod insertion and posterolateral process; posterolateral processes short, 0.31 Plt length, curved, oriented posteriorly.</p><p>Antenna I (Fig. 3 B) length 0.17 body length; flagellum with 5 articles.</p><p>Antenna II (Fig. 3 A) length 0.31 body length (without missing peduncular article 6 and flagellum); article 3 dorsal projection triangular, projection length 0.30 article 3 length; article 5 projection length 0.28 article 5 length; flagellum with 17 articles (inferred from male paratype).</p><p>Mandible (Fig. 4 B, C) incisor with 5 cusps, left Md lacinia mobilis with 4 cusps.</p><p>Maxillipeds (Fig. 4 A) with 3 coupling hooks each.</p><p>Pereopod I (Fig. 3 C) length 0.40 body length. PII (Fig. 3 D) length 0.49 body length. PIII length 0.53 body length. PIV length 0.53 body length. PV length 0.64 body length. PVI (Fig. 3 E) length 0.71 body length; P lengths gradually increasing from PI to PVI, PVII shorter than PVI.</p><p>Pleopod I (Figs 5 A, 26 H) medial lobes subtriangular, projecting caudolaterally; separated at the apex by a narrow gap.</p><p>Pleopod II (Fig. 5 B, C) protopod semi-circular, with distal lobe extending beyond protopod distal margin; endopod stylet 1.6 protopod length.</p><p>Female. Differs from male in the following characters:</p><p>Body (Fig. 2 A) length 2.3 width; oval; anterior body length (Ceph – Prn 4) 0.95 posterior body length (Prn 5 – Plt).</p><p>Cephalothorax (Fig. 2 A, C) length 0.48 width, 0.13 body length, width 0.60 body width; frontal margin width 0.47 Ceph width.</p><p>Pereonite (Fig. 2 A) 4 lateral margin length 1.05 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 2 A, 26 G) length 0.83 width, 0.27 body length, trapezoidal; posterolateral processes 0.20 Plt length, straight.</p><p>Antenna I (Fig. 2 A) length 0.16 body length; flagellum with 4 articles.</p><p>Antenna II (Fig. 2 A) length 0.57 body length; flagellum with 12 articles.</p><p>Operculum (Fig. 26 G) Length 1.0 width, 0.77 Plt length; distal margin with numerous, evenly distributed long setae.</p></div>	https://treatment.plazi.org/id/BC04A7E2765F554B8A48FEB397DB12D1	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Knauber, Henry;Schell, Tilman;Brandt, Angelika;Riehl, Torben	Knauber, Henry, Schell, Tilman, Brandt, Angelika, Riehl, Torben (2025): Across trench and ridge: description of five new species of the Haploniscus belyaevi Birstein, 1963 species complex (Isopoda, Haploniscidae) from the Kuril-Kamchatka Trench region. Zoosystematics and Evolution 101 (2): 813-853, DOI: 10.3897/zse.101.137663
13D95A2E853659AC950D7E6D636BAF09.text	13D95A2E853659AC950D7E6D636BAF09.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Haploniscus erebus Knauber & Riehl 2025	<div><p>Haploniscus erebus Knauber &amp; Riehl sp. nov.</p><p>Figs 1, 10, 11, 12, 13, 26</p><p>Holotype.</p><p>SKB Hap 54, adult male (stage VI), 3.3 mm, MIMB 50317.</p><p>Paratypes.</p><p>SKB Hap 49, adult female (stage IV; genome), SMF 56566;  SKB Hap 50, adult female (stage IV), 3.3 mm, MIMB 50315 .</p><p>Type locality.</p><p>St. LV 71–02 – 07, RV “ Akademik M. A. Lavrentyev ”, SokhoBio expedition, EBS, 3352 m, 46°40.9'N, 147°28.5'E, Northwest Pacific, Sea of Okhotsk, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=147.475&amp;materialsCitation.latitude=46.681667" title="Search Plazi for locations around (long 147.475/lat 46.681667)">Kuril Basin</a>.</p><p>Further records.</p><p>St. LV 71–02 – 07: SKB Hap 26 (manca) MIMB 50312, SKB Hap 28 (manca) MIMB 50313; St. LV 71–04 – 09: SKB Hap 10 (manca) MIMB 50311; St. LV 71–04 – 10: SKB Hap 09 (manca) SMF 56526; St. LV 71–11 – 06: SKB Hap 29 (manca) MIMB 50314, SKB Hap 30 (manca) SMF 56547, SKB Hap 31 (manca) SMF 56548, SKB Hap 51 (manca) MIMB 50316, SKB Hap 52 (manca) SMF 56569, SKB Hap 53 (manca) SMF 56570, SKB Hap 63 (manca) SMF 56580.</p><p>Distribution.</p><p>Northwest Pacific, Sea of Okhotsk, Kuril Basin, depth 3210–3366 m. Visualized in Fig. 27.</p><p>Etymology.</p><p>From “ Erebus ” (Ancient Greek: Ἔρεβος), the Greek mythological personification of darkness. It is a noun in apposition.</p><p>Synonymy.</p><p>Haploniscus aff. belyaevi (see Knauber et al. 2022).</p><p>Diagnosis.</p><p>Haploniscus erebus sp. nov. differs from other species of the  belyaevi - complex in the following characters: rostrum straight, near triangular in lateral view; Plt shape rectangular, posterior margin straight in males; posterolateral processes long, more than 0.50 Plt length in males, straight, oriented posteriorly.</p><p>Molecular diagnosis.</p><p>Differing in the 16 S gene from other species of the  belyaevi - complex in the nucleotides G (position 56 of the alignment), G (64), T (66), G (71), - (150), A (155), T (156), A (204), G (206), C (243), C (342), A (350), G (355), and C (358) as well as the nucleotides T (151), T (154), T (268), T (284), A (286), C (301), G (313), T (352), G (376), C (385), C (388), T (418), A (436), T (451), G (472), G (475), G (502), G (562), and G (565) of the COI gene.</p><p>Description.</p><p>Male. Body (Figs 1 C, 10 B) length 2.2 width; subrectangular; anterior body length (Ceph – Prn 4) 1.1 posterior body length (Prn 5 – Plt); lateral margin interrupted between Prn 7 and Plt, otherwise continuous.</p><p>Cephalothorax (Figs 1 C, 10 B, D) length 0.45 width, 0.13 body length, width 0.61 body width; frontal margin width 0.50 Ceph width; rostrum straight, near triangular laterally.</p><p>Pereonite 1 (Figs 1 C, 10 B) posterior tergite margin through Prn 5 anterior tergite margin delicately serrated, setose; Prn 2–5 anterolateral angles slightly projecting; Prn 2–4 posterolateral angles slightly projecting; Prn 4 lateral margin length 0.89 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 1 C, 10 B, 26 B) length 0.64 width, 0.23 body length, rectangular, posterior margin straight; tergite surface smooth; with posterolateral tergal ridge between uropod insertion and posterolateral process; posterolateral processes long, 0.53 Plt length, straight, oriented posteriorly.</p><p>Antenna I (Fig. 11 B) length 0.18 body length; flagellum with 6 articles.</p><p>Antenna II (Fig. 11 A) length 0.68 body length; article 3 dorsal projection triangular, projection length 0.42 article 3 length; article 5 projection length 0.28 article 5 length; flagellum with 16 articles.</p><p>Mandible (Fig. 12 B, C) incisor with 5 cusps, left Md lacinia mobilis with 5 cusps.</p><p>Maxillipeds (Fig. 12 A) with 3 coupling hooks each.</p><p>Pereopod I (Fig. 11 C) length 0.43 body length. PII (Fig. 11 D) length 0.49 body length. PIII length 0.58 body length. PIV length 0.60 body length. PV length 0.75 body length. PVI (Fig. 11 E) length 0.81 body length. PVII length 0.79 body length; P lengths gradually increasing from PI to PVI, PVII shorter than PVI.</p><p>Pleopod I (Figs 13 A, 26 B) medial lobes subtriangular, projecting caudolaterally; separated at the apex by a narrow gap.</p><p>Pleopod II (Fig. 13 B, C) protopod semi-circular, with distal lobe extending beyond protopod distal margin; endopod stylet 1.8 protopod length.</p><p>Female. Differs from male in the following characters:</p><p>Body (Fig. 10 A) length 2.3 width; oval; anterior body length (Ceph – Prn 4) 0.99 posterior body length (Prn 5 – Plt).</p><p>Cephalothorax (Fig. 10 A, C) length 0.36 width, 0.09 body length, width 0.59 body width; frontal margin width 0.55 Ceph width.</p><p>Pereonite 4 (Fig. 10 A) lateral margin length 1.0 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 10 A, 26 A) length 0.74 width, 0.24 body length, trapezoidal, posterior margin rounded, convex; posterolateral processes short, 0.34 Plt length, oriented posterolaterally.</p><p>Antenna I (Fig. 10 A) length 0.14 body length; flagellum with 4 articles.</p><p>Antenna II (Fig. 10 A) length 0.61 body length; flagellum with 13 articles.</p><p>Operculum (Fig. 26 A) length 0.93 width, 0.81 Plt length; distal margin with numerous, evenly distributed long setae; lateral margins with fewer, evenly distributed short setae.</p></div>	https://treatment.plazi.org/id/13D95A2E853659AC950D7E6D636BAF09	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Knauber, Henry;Schell, Tilman;Brandt, Angelika;Riehl, Torben	Knauber, Henry, Schell, Tilman, Brandt, Angelika, Riehl, Torben (2025): Across trench and ridge: description of five new species of the Haploniscus belyaevi Birstein, 1963 species complex (Isopoda, Haploniscidae) from the Kuril-Kamchatka Trench region. Zoosystematics and Evolution 101 (2): 813-853, DOI: 10.3897/zse.101.137663
C0C4A9BB10B053E2B91F5B5522A6CC44.text	C0C4A9BB10B053E2B91F5B5522A6CC44.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Haploniscus hades Knauber & Riehl 2025	<div><p>Haploniscus hades Knauber &amp; Riehl sp. nov.</p><p>Figs 1, 14, 15, 16, 17, 26</p><p>Holotype.</p><p>KBII Hap 137, adult male (stage VI), 3.7 mm, SMF 56419.</p><p>Paratypes.</p><p>KBII Hap 104, adult female (stage IV; genome), SMF 56388;  KBII Hap 213, adult female (stage IV), 2.4 mm, SMF 56495 .</p><p>Type locality.</p><p>St. SO 250–042, RV “ Sonne ”, KuramBio II expedition, EBS, 7123 m, 45°39.62'N, 152°56.39'E, Northwest Pacific, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=152.93983&amp;materialsCitation.latitude=45.66033" title="Search Plazi for locations around (long 152.93983/lat 45.66033)">hadal Kuril-Kamchatka Trench near Bussol Strait</a>.</p><p>Further records.</p><p>St. SO 250–020: KBII Hap 116 (adult female) SMF 56399; St. SO 250–028: KBII Hap 208 (adult male) SMF 56490; St. SO 250–030: KBII Hap 209 (manca) SMF 56491, KBII Hap 210 (adult female) SMF 56492; St. SO 250–040: KBII Hap 220 (ovigerous female) SMF 56502, KBII Hap 221 (ovigerous female) SMF 56503, KBII Hap 231 (manca) SMF 56513, KBII Hap 232 (manca) SMF 56514; St. SO 250–042: KBII Hap 105 (manca) SMF 56389, KBII Hap 106 (manca) SMF 56390, KBII Hap 165 (adult male) SMF 56447, KBII Hap 198 (manca) SMF 56480, KBII Hap 230 (manca) SMF 56512; St. SO 250–086: KBII Hap 226 (adult male) SMF 56508; St. SO 250–097: KBII Hap 201 (manca) SMF 56483, KBII Hap 204 (adult male) SMF 56486, KBII Hap 205 (adult female) SMF 56487, KBII Hap 206 (ovigerous female) SMF 56488, KBII Hap 214 (manca) SMF 56496, KBII Hap 215 (adult female) SMF 56497, KBII Hap 216 (adult male) SMF 56498, KBII Hap 217 (adult female) SMF 56499, KBII Hap 227 (manca) SMF 56509, KBII Hap 233 (manca) SMF 56515, KBII Hap 234 (manca) SMF 56516; St. SO 250–098: KBII Hap 203 (manca) SMF 56485.</p><p>Distribution.</p><p>Northwest Pacific, Kuril-Kamchatka Trench, depth 5493–8191 m. Visualized in Fig. 27.</p><p>Etymology.</p><p>The specific epithet “  hades ” is a noun in apposition derived from “ Hades ” (Ancient Greek: Ἅιδης), the god and ruler of the underworld in Greek mythology. This name refers to this species distributional range within the hadal depths of the Kuril-Kamchatka Trench and the novel feature of the pleotelson posterior margin tergal plates projecting above the uropods in males. These render the uropods “ invisible ” from dorsal view, reminiscent of Hades’ cap of invisibility.</p><p>Synonymy.</p><p>Haploniscus KKT hadal (see Knauber et al. 2022).</p><p>Diagnosis.</p><p>Haploniscus hades sp. nov. differs from other species of the  belyaevi - complex in the following characters: rostrum curved upwards, basally with dorsal bulge in males; Plt with posterolateral tergal ridge on posterolateral process and posterior margin tergal plates projecting above uropods (solely present in sister species  H. kerberos sp. nov. otherwise); AII article 3 dorsal projection hook-shaped; Plp I distally with hook-shaped projection.</p><p>Molecular diagnosis.</p><p>Differing in the 16 S gene from other species of the  belyaevi - complex in the nucleotide A (position 219 of the alignment) as well as the nucleotides G (103), A (211), T (217), C (232), G (256), T (328), A (349), C (364), C (370), C (442), A (469), C (499), and C (571) of the COI gene.</p><p>Description.</p><p>Male. Body (Figs 1 A, 14 B) length 2.3 width; oval; anterior body length (Ceph – Prn 4) 0.84 posterior body length (Prn 5 – Plt); lateral margin continuous.</p><p>Cephalothorax (Figs 1 A, 14 B, D) length 0.28 width, 0.07 body length, width 0.56 body width; frontal margin width 0.53 Ceph width; rostrum curved upwards, basally with dorsal bulge.</p><p>Pereonite 1 (Figs 1 A, 14 B) posterior tergite margin through Prn 5 anterior tergite margin delicately serrated, setose; Prn 2–4 anterolateral angles slightly projecting; Prn 2–4 posterolateral angles slightly projecting; Prn 4 lateral margin length 0.89 Prn 5 lateral margin length; Prn 5 anterolateral angle not projecting, rectangular.</p><p>Pleotelson (Figs 1 A, 14 B, 26 F) length 0.75 width, 0.27 body length, trapezoidal, posterior margin concave; tergite surface tuberculate, less distinct than in remaining body; with posterolateral tergal ridge on posterolateral process and posterior margin tergal plates projecting above uropods; posterolateral processes minute, 0.04 Plt length, straight, oriented posteriorly.</p><p>Antenna I (Fig. 15 B) length 0.17 body length; flagellum with 6 articles.</p><p>Antenna II (Fig. 15 A) length 0.67 body length; article 3 dorsal projection hook-shaped, projection length 0.39 article 3 length; article 5 projection length 0.26 article 5 length; flagellum with 16 articles.</p><p>Mandible (Fig. 16 B, C) incisor with 6 cusps, left Md lacinia mobilis with 5 cusps.</p><p>Maxillipeds (Fig. 16 A) with 3 coupling hooks each.</p><p>Pereopod I (Fig. 15 C) length 0.41 body length. PIII length 0.53 body length. PIV length 0.54 body length. PV length 0.67 body length. PVI (Fig. 15 E) length 0.70 body length. PVII length 0.69 body length; P lengths gradually increasing from PI to PVI, PVII shorter than PVI.</p><p>Pleopod I (Figs 17 A, 26 F) medial lobes convexly rounded, tapering to an obtuse point; distally with hook-shaped projection; separated at the apex by a narrow gap.</p><p>Pleopod II (Fig. 17 B, C) protopod elongated, suboval; endopod stylet 2.0 protopod length.</p><p>Female. Differs from male in the following characters:</p><p>Body (Fig. 14 A) length 2.4 width; anterior body length (Ceph – Prn 4) 1.0 posterior body length (Prn 5 – Plt).</p><p>Cephalothorax (Fig. 14 A, C) length 0.52 width, 0.14 body length, width 0.63 body width; frontal margin width 0.55 Ceph width.</p><p>Pereonite 4 (Fig. 14 A) lateral margin length 0.93 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 14 A, 26 E) length 0.75 width, 0.25 body length, posterior margin straight; posterolateral processes 0.08 Plt length.</p><p>Antenna I (Fig. 14 A) length 0.15 body length; flagellum with 4 articles.</p><p>Antenna II (Fig. 14 A) length 0.70 body length; flagellum with 11 articles.</p><p>Operculum (Fig. 26 E) length 1.1 width, 0.74 Plt length; distal margin with numerous, evenly distributed long setae; lateral margins with up to 3 short setae each.</p></div>	https://treatment.plazi.org/id/C0C4A9BB10B053E2B91F5B5522A6CC44	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Knauber, Henry;Schell, Tilman;Brandt, Angelika;Riehl, Torben	Knauber, Henry, Schell, Tilman, Brandt, Angelika, Riehl, Torben (2025): Across trench and ridge: description of five new species of the Haploniscus belyaevi Birstein, 1963 species complex (Isopoda, Haploniscidae) from the Kuril-Kamchatka Trench region. Zoosystematics and Evolution 101 (2): 813-853, DOI: 10.3897/zse.101.137663
A19368E9BC2F5FA4BDDF0F0F45D53813.text	A19368E9BC2F5FA4BDDF0F0F45D53813.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Haploniscus kerberos Knauber & Riehl 2025	<div><p>Haploniscus kerberos Knauber &amp; Riehl sp. nov.</p><p>Figs 18, 19, 20, 21, 26</p><p>Holotype.</p><p>KBII Hap 136, adult male (stage VI), 3.1 mm, SMF 56418.</p><p>Paratypes.</p><p>KBII Hap 122, adult female (stage IV; genome), SMF 56405;  KBII Hap 123, adult female (stage IV), 2.4 mm, SMF 56406 .</p><p>Type locality.</p><p>St. SO 250–010, RV “ Sonne ”, KuramBio II expedition, EBS, 5120 m, 43°49.43'N, 151°46.96'E, Northwest Pacific, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=151.78267&amp;materialsCitation.latitude=43.823833" title="Search Plazi for locations around (long 151.78267/lat 43.823833)">abyssal plains southeast of the Kuril-Kamchatka Trench</a>.</p><p>Further records.</p><p>St. LV 71–10 – 06: SKB Hap 13 (manca) MIMB 50318; St. LV 71–10 – 07: SKB Hap 01 (ovigerous female) SMF 56518, SKB Hap 22 (adult male) SMF 56539, SKB Hap 37 (adult male) MIMB 50319; St. SO 250–008: KBII Hap 200 (manca) SMF 56482, KBII Hap 219 (adult female) SMF 56501, KBII Hap 229 (manca) SMF 56511; St. SO 250–010: KBII Hap 119 (adult male) SMF 56402, KBII Hap 120 (adult male) SMF 56403, KBII Hap 121 (adult female) SMF 56404, KBII Hap 135 (ovigerous female) SMF 56417, KBII Hap 228 (manca) SMF 56510; St. SO 250–065: KBII Hap 211 (manca) SMF 56493, KBII Hap 212 (manca) SMF 56494; St. SO 250–085: KBII Hap 222 (adult male) SMF 56504, KBII Hap 223 (adult male) SMF 56505, KBII Hap 224 (adult male) SMF 56506; St. SO 250–087: KBII Hap 218 (ovigerous female) SMF 56500, KBII Hap 225 (adult male) SMF 56507, KBII Hap 235 (ovigerous female) SMF 56517.</p><p>Distribution.</p><p>Northwest Pacific, abyssal regions adjacent to the Kuril-Kamchatka Trench, depth 4469–5755 m. Visualized in Fig. 27.</p><p>Etymology.</p><p>As a noun in apposition, the epithet “  kerberos ” refers to “ Kerberos ” (Ancient Greek Κέρβερος) from Greek mythology, the creature guarding the gates of the underworld. This name relates to this species’ distributional range, which, according to the available data, is limited to the abyssal plains adjacent to the hadal Kuril-Kamchatka Trench.</p><p>Synonymy.</p><p>Haploniscus KKT abyssal (see Knauber et al. 2022).</p><p>Diagnosis.</p><p>Haploniscus kerberos sp. nov. is highly similar to  H. hades sp. nov. in also possessing the characteristic Plt shape with posterolateral tergal ridges terminating on the posterolateral processes and the posterior margin tergal plates projecting above the uropods. It differs from its sister species in the following characters: rostrum basally without dorsal bulge in males (basally with dorsal bulge in  H. hades sp. nov.) and AII article 3 dorsal projection triangular (hook-shaped in  H. hades sp. nov.).</p><p>Molecular diagnosis.</p><p>differing in the 16 S gene from other species of the  belyaevi - complex in the nucleotides G (position 173 of the alignment) and G (228), as well as the nucleotides T (61), C (91), C (298), G (346), G (430), G (607), T (625), and G (649) of the COI gene.</p><p>Description.</p><p>Male. Body (Fig. 18 B) length 2.5 width; oval; anterior body length (Ceph – Prn 4) 1.1 posterior body length (Prn 5 – Plt); lateral margin continuous.</p><p>Cephalothorax (Fig. 18 B, D) length 0.35 width, 0.08 body length, width 0.59 body width; frontal margin width 0.54 Ceph width; rostrum curved upwards.</p><p>Pereonite 1 (Fig. 18 B) posterior tergite margin through Prn 5 anterior tergite margin delicately serrated, setose; Prn 2–4 anterolateral angles slightly projecting; Prn 2–4 posterolateral angles slightly projecting; Prn 4 lateral margin length 0.92 Prn 5 lateral margin length; Prn 5 anterolateral angle not projecting, rectangular.</p><p>Pleotelson (Figs 18 B, 26 D) length 0.68 width, 0.22 body length, trapezoidal, posterior margin concave; tergite surface tuberculate, less distinct than in remaining body; with posterolateral tergal ridge on posterolateral process and posterior margin tergal plates projecting above uropods; posterolateral processes minute, 0.09 Plt length, straight, oriented posteriorly.</p><p>Antenna I (Fig. 19 B) length 0.20 body length; flagellum with 6 articles.</p><p>Antenna II (Fig. 19 A) length 0.77 body length; article 3 dorsal projection triangular, projection length 0.31 article 3 length; article 5 projection length 0.22 article 5 length; flagellum with 16 articles.</p><p>Mandible (Fig. 20 B, C) incisor with 5 cusps, left Md lacinia mobilis with 4 cusps.</p><p>Maxillipeds (Fig. 20 A) with 3 coupling hooks each.</p><p>Pereopod I (Fig. 19 D) length 0.43 body length. PVI (Fig. 19 C) length 0.70 body length; P lengths gradually increasing from PI to PVI, PVII shorter than PVI.</p><p>Pleopod I missing.</p><p>Pleopod II (Fig. 21 A, B) protopod elongated, suboval; endopod stylet 2.0 protopod length.</p><p>Female. Differs from male in the following characters:</p><p>Body (Fig. 18 A) length 2.7 width; anterior body length (Ceph – Prn 4) 0.94 posterior body length (Prn 5 – Plt).</p><p>Cephalothorax (Fig. 18 A, C) length 0.50 width, 0.12 body length, width 0.66 body width; frontal margin width 0.55 Ceph width.</p><p>Pereonite 4 (Fig. 18 A) lateral margin length 0.80 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 18 A, 26 C) length 0.84 width, 0.24 body length, posterior margin rounded, convex; with posterolateral tergal ridge between uropod insertion and posterolateral process; posterolateral processes short, 0.23 Plt length.</p><p>Antenna I (Fig. 18 A) length 0.14 body length; flagellum with 4 articles.</p><p>Antenna II (Fig. 18 A) length 0.67 body length; flagellum with 12 articles.</p><p>Operculum (Fig. 26 C) length 1.1 width, 0.75 Plt length; distal margin with numerous, evenly distributed long setae; lateral margins with 2 short setae each.</p></div>	https://treatment.plazi.org/id/A19368E9BC2F5FA4BDDF0F0F45D53813	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Knauber, Henry;Schell, Tilman;Brandt, Angelika;Riehl, Torben	Knauber, Henry, Schell, Tilman, Brandt, Angelika, Riehl, Torben (2025): Across trench and ridge: description of five new species of the Haploniscus belyaevi Birstein, 1963 species complex (Isopoda, Haploniscidae) from the Kuril-Kamchatka Trench region. Zoosystematics and Evolution 101 (2): 813-853, DOI: 10.3897/zse.101.137663
F15FB4C76CF051AA9A301C37681E021D.text	F15FB4C76CF051AA9A301C37681E021D.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Haploniscus nyx Knauber & Riehl 2025	<div><p>Haploniscus nyx Knauber &amp; Riehl sp. nov.</p><p>Figs 22, 23, 24, 25, 26</p><p>Holotype.</p><p>SKB Hap 34, adult male (stage VI), 3.4 mm, MIMB 50320.</p><p>Paratypes.</p><p>SKB Hap 21, adult female (stage IV), 3.0 mm, MIMB 50321 .</p><p>Type locality.</p><p>St. LV 71–10 – 07, RV “ Akademik M. A. Lavrentyev ”, SokhoBio expedition, EBS, 4469 m, 46°07.8'N, 152°10.3'E, Northwest Pacific, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=152.17166&amp;materialsCitation.latitude=46.13" title="Search Plazi for locations around (long 152.17166/lat 46.13)">abyssal branch of the Kuril-Kamchatka Trench into the Bussol Strait</a>.</p><p>Further records.</p><p>St. LV 71–10 – 07: SKB Hap 35 (adult male), SMF 56552.</p><p>Distribution.</p><p>Only known from type locality. Northwest Pacific, abyssal region adjacent to the Kuril-Kamchatka Trench to the northwest, depth 4769 m. Visualized in Fig. 27.</p><p>Etymology.</p><p>The epithet “  nyx,” a noun in apposition, is derived from “ Nyx ” (Ancient Greek Νύξ), the goddess of the night in Greek mythology.</p><p>Synonymy.</p><p>Haploniscus SO - WTA (see Knauber et al. 2022).</p><p>Diagnosis.</p><p>Haploniscus nyx sp. nov. differs from other species of the  belyaevi - complex in the following character: pleotelson posterior margin concave in males; Plp I medial lobes convexly rounded, tapering to an obtuse point, distally without a hook-shaped protrusion.</p><p>Molecular diagnosis.</p><p>differing in the 16 S gene from other species of the  belyaevi - complex in the nucleotides G (position 25 of the alignment) and C (312) as well as the nucleotides C (124), G (148), C (193), T (206), C (304), G (334), C (346), G (481), T (496), C (508), C (520), G (553), G (556), and C (628) of the COI gene.</p><p>Description.</p><p>Male. Body (Fig. 22 B) length 2.2 width; subrectangular; anterior body length (Ceph – Prn 4) 0.99 posterior body length (Prn 5 – Plt); lateral margin continuous.</p><p>Cephalothorax (Fig. 22 B, D) length 0.30 width, 0.07 body length, width 0.55 body width; frontal margin width 0.46 Ceph width; rostrum curved upwards.</p><p>Pereonite 1 (Fig. 22 B) posterior tergite margin through Prn 5 anterior tergite margin delicately serrated, setose; Prn 2–5 anterolateral angles slightly projecting; Prn 1–4 posterolateral angles slightly projecting; Prn 4 lateral margin length 1 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 22 B, 26 L) length 0.72 width, 0.23 body length, trapezoidal, posterior margin concave; tergite surface smooth; with posterolateral tergal ridge between uropod insertion and posterolateral process; posterolateral processes minute, 0.13 Plt length, straight, oriented posteriorly.</p><p>Antenna I (Fig. 23 B) length 0.16 body length; flagellum with 5 articles.</p><p>Antenna II (Fig. 23 A) length 0.61 body length; article 3 dorsal projection triangular, projection length 0.36 article 3 length; article 5 projection length 0.23 article 5 length; flagellum with 15 articles.</p><p>Mandible (Fig. 24 B, C) incisor with 5 cusps, left Md lacinia mobilis with 4 cusps.</p><p>Maxillipeds (Fig. 24 A) with 3 coupling hooks each.</p><p>Pereopod I (Fig. 23 C) length 0.37 body length. PII (Fig. 23 D) length 0.45 body length. PIII (Fig. 23 E) length 0.52 body length. PV length 0.65 body length. PVI length 0.70 body length; P lengths gradually increasing from PI to PVI, PVII shorter than PVI.</p><p>Pleopod I (Figs 25 A, 26 L) medial lobes convexly rounded, tapering to an obtuse point; adjoining at the apex.</p><p>Pleopod II (Fig. 25 B, C) protopod semi-circular, with distal lobe extending beyond protopod distal margin; endopod stylet 2.1 protopod length.</p><p>Female. Differs from male in the following characters:</p><p>Body (Fig. 22 A) length 2.1 width; oval; anterior body length (Ceph – Prn 4) 0.98 posterior body length (Prn 5 – Plt).</p><p>Cephalothorax (Fig. 22 A, C) length 0.46 width, 0.12 body length, width 0.55 body width; frontal margin width 0.46 Ceph width.</p><p>Pereonite 4 (Fig. 22 A) lateral margin length 1.05 Prn 5 lateral margin length.</p><p>Pleotelson (Figs 22 A, 26 K) length 0.83 width, 0.27 body length, posterior margin rounded, convex; posterolateral processes short, 0.19 Plt length.</p><p>Antenna I (Fig. 22 A) length 0.16 body length; flagellum with 4 articles.</p><p>Antenna II (Fig. 22 A) length 0.50 body length; flagellum with 15 articles.</p><p>Operculum (Fig. 26 K) length 0.98 width, 0.66 Plt length; distal margin with numerous, evenly distributed long setae; lateral margins with fewer, evenly distributed short setae.</p></div>	https://treatment.plazi.org/id/F15FB4C76CF051AA9A301C37681E021D	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Knauber, Henry;Schell, Tilman;Brandt, Angelika;Riehl, Torben	Knauber, Henry, Schell, Tilman, Brandt, Angelika, Riehl, Torben (2025): Across trench and ridge: description of five new species of the Haploniscus belyaevi Birstein, 1963 species complex (Isopoda, Haploniscidae) from the Kuril-Kamchatka Trench region. Zoosystematics and Evolution 101 (2): 813-853, DOI: 10.3897/zse.101.137663
