Scottocheres mipoensis, Kim, 2016

Kim, Il-Hoi, 2016, Siphonostomatoid copepods (Crustacea) mainly associated with marine invertebrates from Korean waters, Journal of Species Research 5 (3), pp. 393-442 : 423-428

publication ID	https://doi.org/ 10.12651/JSR.2016.5.3.393
persistent identifier	https://treatment.plazi.org/id/96353C58-E77A-FF80-FC8E-F8ACFF0CFB44
treatment provided by	Felipe
scientific name	Scottocheres mipoensis
status	sp. nov.

Treatment

Scottocheres mipoensis View in CoL n. sp. ( Figs. 21-23 View Fig View Fig View Fig )

Material examined. Two $$, 1♂ from a sponge (as a fisheries bycatch), off Mipo (35°09′29″N, 129°10′17″E) in Pusan, 11 December 2014. Holotype ($, intact, NIBR GoogleMaps

IV0000681227 ) has been deposited in NIBR, Incheon, Korea. Dissected paratypes (1$, 1♂) are retained in the collection of the author .

Female. Body ( Fig. 21A View Fig ) narrow, 1.01 mm long. Prosome 629 μm long. Cephalothorax 327 × 295 μm, longer than wide. Second and third pedigerous somites 276 and 269 μm wide, respectively, only slightly narrower than cephalothorax, with rounded anterolateral and posterolateral corners. Fourth pedigerous somite 131 μm wide. Urosome ( Fig. 21B View Fig ) 4segmented. Fifth pedigerous somite nearly as wide as genital doublesomite. Genital doublesomite 185 × 133 μm, slightly tapering in distal half, with pointed, toothlike process on lateral margin near genital aperture; lateral sides of dorsal surface depressed, thus forming dorsal ridge along midline; genital aperture located dorsally at anterior 0.3 region. Minute paired gonopores present on ventral surface at anterior fourth of doublesomite ( Fig. 21C View Fig ). First abdominal somite 73 × 69 μm, gradually broadened distally. Anal somite 42 × 62 μm, distinctly wider than long, shorter than preceding somite. Caudal ramus ( Fig. 21D View Fig ) small, 19 × 19 μm, broadened distally, with few setules on distal part of inner margin, and armed with 6 setae; seta V longest, 173 μm long; seta IV second longest, 111 μm long; seta VII (dorsal seta) inserted on papilliform extention of caudal ramus.

Rostrum absent. Antennule ( Fig. 21E View Fig ) 289 μm long, 18segmented, but articulation between third and fourth segments incomplete; armature formula 1, 2, 2, 2, 2 / 2, 2, 2, 5, 2 / 2, 1, 2, 1, 1 / 1, 1 + aesthetasc, and 13; first segment with several minute spinules on anterior surface; all setae short and naked; aesthetasc on penultimate segment about 0.28 times as long as antennule. Antenna ( Fig. 21F View Fig ) consisting of syncoxa, basis, small exopod and 2segmented endopod. Syncoxa short and unarmed. Basis 72 μm long. Exopod 12 × 6 μm, twice as long as wide, located at distal 1/3 of basis length, and armed with 3 small setae. Proximal endopodal segment about 45 μm long and unarmed; distal endopodal segment about 23 μm long, armed with 4 setae and terminal claw; inner distal one of setae minute; terminal claw 58 μm long.

Oral siphon ( Fig. 21G View Fig ) thin, 636 μm long, and extending to level of leg 5. Mandible ( Fig. 21G View Fig ) fibrillike. Maxillule ( Fig. 21H View Fig ) bilobed; inner lobe tapering, 41 × 19 μm, armed distally with 3 setae (144, 133, and 68 μm, respectively); outer lobe small, 11 × 5 μm, armed with 1 distal and 1 subdistal setae. Maxilla ( Fig. 22A View Fig ) with unarmed, 100 μm-long syncoxa; basis also 100 μm long, slender; terminal claw 68 μm long, gently curved, and clearly articulated from basis. Maxilliped ( Fig. 22B View Fig ) 5 segmented; syncoxa with 1 small inner distal seta; basis 91× 25 μm, unarmed, but with several minute spinules in middle of outer margin; endopod slender, 3segmented, armed with 2, 1, and 1 setae on first to third segments, respectively; terminal endopodal segment 41 μm long; terminal claw 72 μm long, 1.76 times as long as terminal endopodal segment.

Legs 14 ( Fig. 22 View Fig CF) with 3segmented exopod and endopod. Leg 1 with monocuspid outer distal corner of second endopodal segment, but that of legs 24 bicuspid. Leg 1 lacking inner seta on coxa; inner distal corner of basis with spinules; distal spine 16μm long; outer spines on exopod usually tipped with setule. Terminal spine on exopods of legs 24 curved outwards. Distal seta on third endopodal segment of leg 3 short and rodshaped. Armature formula for legs 14 as follows:

Coxa Basis Exopod Endopod

Leg 1: 00 1I I1; I1; III, 4 01; 01; 1, 2, 3 Leg 2: 01 10 I1; I1; II, I, 4 01; 02; 1, 2, 3 Leg 3: 01 10 I1; I1; II, I, 4 01; 02; 1, 1 + I, 3 Leg 4: 01 10 I1; I1; II, I, 3 01; 02; 1, I, 2

Leg 5 ( Fig. 23A View Fig ) consisting of free protopod and exopod. Protopod 59 × 84 μm and armed with 1 outer and 1 minute inner setae. Exopod 108 × 50 μm, 2.16 times as long as wide, gradually narrowed distally, and armed with 3 small setae (2 distal and 1 subdistal). Leg 6 represented by 2 setae and 1 spine in genital area ( Fig. 23B View Fig ).

Male. Body ( Fig. 23C View Fig ) resembling that of female. Body length 825 μm. Prosome 524 μm long. Cephalothorax 309 × 269 μm. Urosome ( Fig. 23D View Fig ) 5segmented. Fifth pedigerous somite 107 μm wide, much narrower than genital somite. Genital somite 121 × 156 μm. Three abdominal somites 43 × 67, 36 × 58, and 35 × 55 μm, respectively. Caudal ramus 19 × 19 μm.

Rostrum as in female. Antennule ( Fig. 23E View Fig ) 299 μm long, 16segmented, with geniculation between 14th and 15th segments; armature formula 1, 2 + aesthetasc, 1, 2 + aesthetasc, 2 / 2, 2, 2, 5, 2 + aesthetasc / 4 + aesthetasc, 2, 2 + aesthetasc, 2, 3 + aesthetasc, and 11. Articulation incomplete between third and fourth segments. Eleventh segment with 2 transverse rows of spinules on posterior side. All of setae small and naked. Antenna as in female.

Oral siphon, mandible, maxillule, maxilla as in female. Maxilliped with 1 blunt, proximal process on inner margin of basis.

Leg 1 as in female. Leg 2 endopod ( Fig. 23G View Fig ) with 3 distal dentiform processes on terminal segment ( Fig. 23G View Fig ). Leg 3 endopod ( Fig. 23H View Fig ) with 1 large dentiform process at outer distal corner of second segment and wrinkles on ventral surface of same segment; third segment with curved, large terminal process and armed with 1 outer seta, 1 stout terminal spine, and 3 inner setae (armature formula 1, I, 3). Leg 4 as in female.

Leg 5 ( Fig. 23I View Fig ) consisting of free protopod and exopod; protopod 29 × 67 μm, much wider than long, with fine spinules along inner part of distal margin; exopod suboval, 36 × 25 μm, with fine spinules on both margins and armed with 1 plumose subdistal and 2 naked distal setae. Leg 6 ( Fig. 23J View Fig ) represented by 2 lobes tipped by 1 and 2 naked setae, respectively, on genital operculum.

Etymology. The type locality of the new species, Mipo in Pusan, is taken for the name of the species.

Remarks. Eight known species of Scottocheres show variabilities with species in the armatures of the third exopodal segment of leg 1 and the third exopodal and endopodal segments of legs 24. Scottocheres mipoensis n. sp. share a same armature formula of legs 14 with only one congener, S. laubieri Stock, 1969 . In these two species, the armature formula of the third exopodal segments of legs 24 are II, I, 4; II, I, 4; II, I, 4; and II, I, 3, respectively, and those of the third endopodal segments of legs 14 are 1, 2, 3; 1, 2, 3; 1, 1+ I, 3; and 1, I, 2, respectively.

Scottocheres laubieri has, as originally described by Stock (1967), the following features, unlike S. mipoensis n. sp.: (1) the antennule is 17segmented (vs. 18segmented in S. mipoensis ) in the female and 15segmented (vs. 16segmented) in the male; (2) the outer lobe of the maxillule with 2 distal setae (vs. 3 distal setae); (3) the exopod of leg 5 in the female is less than twice as long as wide(vs. more than twice as long as wide); (4) spines on the exopods of legs 24 are large (vs. small); and (5) the third endopodal segment of leg 3 in the male with 2 dentiform distal process (vs. 1 large distal process) and the terminal spine on the same segment is elongate (vs. stout).