Setaphyes kielensis
Creators: name: González-Casarrubios, Alberto
name: Cepeda, Diego
name: Neuhaus, Birger
name: García-Cobo, Marta
name: Pardos, Fernando
name: Ürkmez, Derya
name: Sánchez, Nuria
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Kinorhyncha
Allomalorhagida
Pycnophyidae
Setaphyes
Setaphyes kielensis

description: 3.2. Redescription of Setaphyes kielensis (Zelinka, 1928)
Figs 9–14, Tables 3–4.
3.2.1. Diagnosis
Setaphyes with middorsal elevations on segments 1–9, superficially covered by tufts of elongated, thick hairs. Paradorsal setae on segments 2–9 (that of segment 8 unpaired). Laterodorsal setae on segments 2–9. Lateroventral setae on segments 2–10. Ventromedial setae on segments 3–9. Lateral terminal spines short, slender (males LTS:TL average ratio 31.4 %; females LTS:TL average ratio 9 %; males and females average ratio 19.1 %).
3.2.2. Material examined
59 specimens collected from two different populations located in the Anatolian Peninsula and North Frisia. Material from Anatolia are new records for the region, which includes four females mounted for LM, and one female studied with SEM (ZMB 12745, station YSL09 R2, 13 July 2019, 41 Ǫ 24.738 ′ N, 036 Ǫ 39.210 ′ E, 76 m depth; collector: Derya Ürkmez). Material from Germany (Sylt) included 17 males and 15 females mounted for LM (ZMB 12364–12365 were studied only for the intraspecific variability, same sampling locality as for the remaining LM specimens included in the Supplementary Table I); and 22 adults for SEM (22 June 2016, 54 Ǫ 57 ′ 15 ′′ N, 008 Ǫ 21 ′ 34 ′′ E, precision 50 m, collectors: Birger Neuhaus and Hiroshi Yamasaki) (10 males: ZMB 12455, 12457, 12458, 12461–12463, 12468, 12 470, 12472, 12477; 12 females: ZMB 12454, 12456, 12460, 12464, 12465, 12467, 12469, 12471, 12474–12476, 12478). Detailed information of the sampling localities of each LM specimen is provided in the Supplementary Table I.
3.2.3. Description
See Table 3 and Supplementary Table III for measurements and dimensions and Table 4 for summary of middorsal cuticular specialization, seta, tube, nephridiopore and sensory spot locations.
Nine, equally sized outer oral styles in Ring 00 of mouth cone. Each outer oral style formed by a single, flexible unit, wider at base, and showing a sheath with up to 13 fringed rows broader at the proximal region and becoming narrower towards the pointed tip (Figs 3; 11A). Trapezoidal, superficially smooth, cuticular thickenings in between the outer oral styles, with two basal, short, fringed rows (Fig. 11A). Outer oral styles arranged one by each introvert sector, except in sector 6 where a style is missing (Fig. 3). Inner rings of mouth cone not observed and, hence, detailed information on the morphology and distribution of inner styles is not provided.
Introvert with six rings of spinoscalids and 10 longitudinal sectors defined by the disposition of the primary spinoscalids. Scalid and trichoscalid arrangement and morphology as described for S. dentatus (Figs 3; 10A; 11A–D).
Neck with four dorsal and two ventral, sclerotized placids (Figs 9A–C; 10B–C; 11D). Dorsal placids rectangular, with a slightly convex anterior margin; mesial ones broader (ca. 32 μm wide at base) than lateral ones (ca. 23 μm wide at base) (Figs 9B; 10B; 11D). Ventral placids (ca. 21 μm wide at base) morphologically similar to the dorsal ones but much more elongated, getting thinner towards the lateral sides (Figs 9A, C; 10C).
Trunk with eleven segments (Figs 9A–B; 12A, F; 13A, D). Segment 1 with one tergal, two episternal and one trapezoidal, midsternal plate; remaining ones with one tergal and two sternal cuticular plates (Figs 9A–D; 10B–C, E–F, H–I; 12A–C, E–H; 13A–F; 14A–C, F). Sternal plates reaching their maximum width at segment 5, almost constant in width throughout the trunk (Figs 9A–B; 12A, F; 13A, D; 14A, F). Sternal cuticular plates relatively narrow (MSW-5:TL average ratio = 30 %) (Figs 9A–B; 12A, F). Middorsal elevations on segments 1–9, quite inconspicuous, rectangular, narrow, distally blunted, not projecting beyond the posterior margin of segments (Figs 9B; 10B, E, G–H). Paired, paradorsal, butterfly to trident-like intracuticular atria associated to the middorsal structures (Fig. 10G). Cuticular scars (possibly glandular cell outlets) as minute, dot-shaped, rounded to oval perforations throughout the cuticle on segments 1–11 (Figs 9A–D; 10B–I); the number and position of these structures vary greatly among the analysed specimens, with no specific pattern. Up to three pairs of conspicuous laterodorsal and ventromedial cuticular ridges on segments 2–10 (Fig. 9A–D). Cuticular hairs acicular, non-bracteate, distributed throughout the trunk on segments 1–10 not following any particular pattern and giving the animal a furry appearance (Figs 12A–I; 13A–F; 14A–D). Pachycycli and ball-and-socket joints conspicuous on segments 2–9, reduced on most posterior segments, and also depending on maturation of specimens (Fig. 9A–D). Apodemes on segments 9–10 (Figs 9A, D; 10H–I). Primary pectinate fringes finely serrated (Figs 10D; 12H; 13F); secondary pectinate fringes as a wavy, single line along the entire dorsal side with two subdorsal indentations pointing backwards. Ventral secondary pectinate fringes as a wavy, single line in ventromedial or paraventral positions (Fig. 9A–D). Muscular scars as conspicuous, rounded to oval, hairless areas in laterodorsal and ventrolateral positions on segments 1–10 (Figs 9A–D; 13B, E; 14B–D).
Segment 1 with middorsal elevation not projecting beyond the posterior margin of the segment, with paradorsal, butterfly to trident-like atria of associated paradorsal sensory spots (Figs 9B; 10B). Anterolateral margins of the tergal plate as triangular, short, wide, distally rounded extensions (Figs 9A–C; 10B–C; 13B). Episternal plates with usually four, scattered, minute, dot-shaped glandular cell outlets (Fig. 9A, C). Trapezoidal midsternal plate, wider at the base (ca. 29 μm wide at the most anterior margin, ca. 56 μm wide at the most posterior margin; average ratio =52 %), with parallel lateral margins (Figs 9A, C; 10C). Two pairs of sensory spots in subdorsal position, and one pair in laterodorsal and paradorsal positions, the latter towards the middle region of the segment (Figs 9B; 10B; 13A–B). Sensory spots on this and following segments as oval areas with several rows of cuticular micropapillae surrounding a single pore (Fig. 12D).
Segment 2 with middorsal elevation as on the preceding segment (Figs 9B; 10B). Setae in paradorsal, laterodorsal and lateroventral positions; females with additional pair of sexually dimorphic ventrolateral setae (Figs 9A–C; 10B–C; 12B–D; 13B; 14B, D). Males with tubes in ventromedial position (Figs 9A; 12C; 14A). Sensory spots in paradorsal (not near the posterior margin), subdorsal, laterodorsal and ventromedial positions (Figs 9A–C; 10B–C; 12B–C; 13B).
Segment 3 with middorsal elevation as on the preceding segments (Fig. 9B, G). Setae in paradorsal, laterodorsal, lateroventral and ventromedial positions. Sensory spots in paradorsal (not near the posterior margin), subdorsal, laterodorsal and ventromedial positions (Figs 9A–C; 10B–C, G; 12B, D; 13B; 14B).
Segments 4 to 7 similar to segment 3 in the arrangement of cuticular elevation, setae and sensory spots (Figs 9A–B; 10D–G; 12B, E; 13B, E; 14B–C).
Segment 8 with middorsal elevation as on the preceding segments (Figs 9B; 10H). Unpaired seta in paradorsal position, at the right side of the middorsal elevation; paired setae in laterodorsal, lateroventral and ventromedial positions. Sensory spots in paradorsal (not near the posterior margin), subdorsal (two pairs), laterodorsal and ventromedial positions (Figs 9A–B; 10H–I; 12E; 13C).
Segment 9 with middorsal elevation as on the preceding segments (Figs 2B; 10H). Setae in paradorsal, laterodorsal, lateroventral and ventromedial positions. Sensory spots in paradorsal (not near the posterior margin), subdorsal (two pairs), laterodorsal, and ventrolateral positions (Figs 9A–B, D; 10H–I; 12G; 13F). Nephridiopores as small opening surrounded by short tubes in lateroventral position (Fig. 10I).
Segment 10 without middorsal cuticular specialization. Setae in lateroventral position. Two pairs of sensory spots in subdorsal position (Figs 9A–B, D; 10I; 12G–H; 13F). Tergal plate with rounded posterior margin; posterior margins of sternal plates straight in females, more pointed in males.
Segment 11 without middorsal cuticular specialization. Males with two lateral pairs of stout, thick penile spines and with one pair of collapsed tubes terminating in penile bristles (Figs 9A; 10K; 12I). Short lateral terminal spines, longer in males than in females (males LTS:TL average ratio 31.43 %; females LTS:TL average ratio 9.0 1 %) (Figs 9A–B, D; 10J–K; 12F–H).
3.2.4. Intraspecific variation Due to the preservation conditions of the material, the arrangement of sensory spots throughout the trunk could not be fully confirmed in all the examined specimens from Sylt (North Frisia). The remaining cuticular characters of taxonomic relevance for pycnophyids (i.e. setae, middorsal cuticular specializations, spines, glandular cell outlets, and ornamentation) could be examined in detail both in the Anatolian (four females) and the North Frisian (14 males and 12 females; ZMB 12364–12365 were only studied for this purpose) populations.
Anatolian population: Deviations from the common pattern of paradorsal setae distribution in segment 5 were observed in one female from Yesilirmak River mouth, with a single paradorsal seta present on one side of the middorsal elevation, only one seta of the laterodorsal pair commonly present on segment 5, and an unpaired paradorsal seta on segment 7 (ZMB 12741). Segment 8 in two female specimens off Sakarya river mouth (ZMB 12741, 12744) with the paradorsal seta on the left side of the middorsal elevation. The laterodorsal pair of setae on segment 9 could not be confirmed in two females (ZMB 12743, 12744).
North Frisian population: Deviations from the described bilateral pattern were observed in several specimens, both for seta and sensory spot distribution.Segment 2 with double laterodorsal setae on one side in two females (ZMB 12454, Fig. 14D; ZMB 12475, Fig. 14B) and absent on one side in one male (ZMB 12463); lateroventral seta absent on one side in one female (ZMB 12467) and one female (ZMB 12474); ventrolateral setae absent in one female (ZMB 12454); both ventromedial tube and seta present on one sternal plate in one male (ZMB 12457). Segment 3 without the laterodorsal seta on one side in five males (ZMB 12457, 12461, 12463, 12468, 12472) and six females (ZMB 12454, 12460, 12467, 12471, 12476, 12478); with minute laterodorsal seta on one side in four males (ZMB 12458, 12462, 12470, 12477) and four females (ZMB 12456, 12464, 12465, 12469); with triple laterodorsal seta in one female (ZMB 12475, Fig. 14B); ventromedial seta on one sternal plate absent in one female (ZMB 12460); with minute ventromedial setae on both sternal plates in one male (ZMB 12461); with minute ventromedial seta on one sternal plate in four males (ZMB 12462, 12463, 12468, 12470); typical male tube of the segment 2 present on one sternal plate in one male (ZMB 12458; Fig. 14A); laterodorsal sensory spot absent on one side in three males (ZMB 12455, 12457, 12472) and one female (ZMB 12475). Segment 4 without laterodorsal seta on one side in one male (ZMB 12477); lateroventral seta absent on one side in one female (ZMB 12476); laterodorsal sensory spot of one side located more dorsally than the laterodorsal seta in one male (ZMB 12457). Segment 5 without the paradorsal seta on one side of the middorsal elevation in two females (ZMB 12474, 12476); laterodorsal seta absent on one side in one male (ZMB 12457); with two pairs of lateroventral setae on one side in one female (ZMB 12475); with ventrolateral seta on one side instead of the common lateroventral seta in one female (ZMB 12456); with two pairs of lateroventral setae in one female (ZMB 12464); with double ventromedial setae on one sternal plate in one male (ZMB 12470; Fig. 14C); with a single paradorsal sensory spot on the middorsal elevation in one male (ZMB 12477) and one female (ZMB 12474); without one subdorsal sensory spot in one female (ZMB 12467); without one laterodorsal sensory spot in seven males (ZMB 12455, 12458, 12461, 12468, 12470, 12472, 12477) and eight females (ZMB 12456, 12465, 12467, 12469, 12471, 12474, 12476, 12478). Segment 6 without laterodorsal seta on one side in one male (ZMB 12457); lateroventral seta on one side absent in one male (ZMB 12457) and one female (ZMB 1469); with three pairs of lateroventral setae on one side in one female (ZMB 12475); ventrolateral seta on one sternal plate in one male (ZMB 12457); subdorsal sensory spot on one side absent in one male (ZMB 12457). Segment 7 with only an unpaired paradorsal seta on one side of the middorsal elevation in two males (ZMB 12365, ZMB 12367) and one female (ZMB 12464); with a single paradorsal sensory spot on one side in one female (ZMB 12464); without the paradorsal pair of sensory spots in one female (ZMB 12474); without laterodorsal sensory spot on one side in two males (ZMB 12462, 12472) and one female (ZMB 12478). Segment 8 with the paradorsal seta on the left side of the middorsal elevation in four males (ZMB 12367, 12463, 12470, 12472) and five females (ZMB 12465, 12469, 12474–12476); lateroventral seta absent on one side in one male (ZMB 12458) and two females (ZMB 12454, 12471); paradorsal sensory spots absent in one female (ZMB 12476); laterodorsal sensory spot on one side absent in one male (ZMB 12462) and two females (ZMB 12454, 12475). Segment 9 with a single paradorsal seta present on one side of the middorsal elevation in one female (ZMB 12464); with minute laterodorsal seta on one side in two males (ZMB 12461, 12472) and one female (ZMB 12476); laterodorsal pair absent in one male (ZMB 12462); laterodorsal seta absent on one side in two females (ZMB 12464, 12465); paradorsal sensory spots absent in one female (ZMB 12476); without laterodorsal sensory spot on one side in one female (ZMB 12475); without the ventrolateral sensory spot on one sternal plate but with a ventromedial sensory spot in one male (ZMB 12470). Segment 10 with a ventrolateral seta on one sternal plate and without the lateroventral one in one female (ZMB 12475).
description: Published as part of González-Casarrubios, Alberto, Cepeda, Diego, Neuhaus, Birger, García-Cobo, Marta, Pardos, Fernando, Ürkmez, Derya & Sánchez, Nuria, 2023, The genus Setaphyes (Kinorhyncha, Pycnophyidae) in European waters: Redescription of Setaphyes dentatus (Reinhard, 1881) and Setaphyes kielensis (Zelinka, 1928), including notes on morphometrics, sexually dimorphic features and reproduction of the genus, pp. 90-111 in Zoologischer Anzeiger 303 on pages 100-107, DOI: 10.1016/j.jcz.2022.12.004, http://zenodo.org/record/8164206