Cyclopina curtijeju, Karanovic, 2020

Karanovic, Tomislav, 2020, Four new Cyclopina (Copepoda, Cyclopinidae) from South Korea, ZooKeys 992, pp. 59-104 : 59

Cyclopina curtijeju sp. nov. Figures 11 , 12 , 17C

Type locality.

South Korea, South Coast, Jeju Island, Gwangchigi Beach near Seongsan Sunrise Peak, 33°27.122'N, 126°55.481'E.

Specimens examined.

Holotype female dissected on one slide, collected from the type locality, 14 April 2014, leg. T. Karanovic. Paratype female on an SEM stub (together with specimens of other three species described here; row no. 3), collected from the type locality, 14 April 2014, leg. T. Karanovic.

Etymology.

The species name is composed of the Latin adjective curtus (= short), referring to its short caudal rami, and the name of the type locality (Jeju). It should be treated as a noun (gender feminine) in apposition to the generic name.

Description.

Female (based on holotype and one paratype). Body length 400 μm. Colour (Fig. 17C ), nauplius eye, body segmentation, integument on somites (Fig. 12 ), and general habitus as in C. busanensis , except for different sensilla and pores pattern on prosomites (Fig. 12A-D ) and hyaline fringes of urosomites (except anal somite) rather wavy than serrated (Fig. 12F-H ). Prosome ca. 1.4 × as long as urosome.

Genital double-somite (Fig. 12E, F ) as in C. busanensis , except with two additional dorsolateral pair of pores, one additional ventrolateral pair of pores, posterior lateral pore almost at same level as posterior lateral sensillum (instead of being anterior to posterior lateral sensillum), and sensillum instead of large pore at dorsal end of lateral row of spinules. Genital field not clearly observed because of mounting, but in lateral view seems very similar to that in C. busanensis . Fourth urosomite (Fig. 12G ) as in C. busanensis , except with one additional pair of dorsal pores in anterior half. Fifth urosomite (Fig. 12G ) and sixth urosomite (Fig. 12H ) as in C. busanensis .

Caudal rami (Fig. 12A, H ) cylindrical, ca. 1.3 × as long as wide, 1.2 × as long as anal somite, narrowly spaced on anal somite, parallel; ornamented as in C. busanensis ; most armature broken off; dorsal seta nearly 3 × as long as ramus; proximal lateral seta inserted at approximately midlength of ramus.

Antennula (Fig. 13B ) 11-segmented, but all armature as in C. koreana ; armature formula 3.6.8.4.5.6.2.2.2.2.7+ae; sixth segment ca. 2.7 × as long as wide, nearly 0.9 × as long as subsequent five segments combined; tenth segment 1.5 × as long as wide.

Antenna and mandibula (Fig. 13C ) shape, segmentation, armature, and ornamentation as in C. koreana .

Maxillula (Fig. 13D ) also as in C. koreana , except endopod slightly slenderer.

Maxilla (Fig. 13E ) with only two setae on second endopodal segment; everything else as in C. koreana .

Maxilliped (Fig. 13F ) generally as in C. koreana , except first endopodal segment slightly slenderer, seta on fourth endopodal segment shorter, large setae on fifth endopodal segment stronger, and slender seta on fifth endopodal segment shorter.

Swimming legs (Fig. 13G-J ) shape, segmentation, armature formula, and most ornamentation as in C. busanensis ; fourth leg (Fig. 13J ) with three setae on endopod lanceolate as in C. koreana , five setae on third exopodal segment as in C. busanensis , but unlike these species with two parallel posterior rows of spinules on intercoxal sclerite and with posterior row of spinules on basis; third endopodal segment of fourth leg 1.6 × as long as wide and third exopodal segment of fourth leg ca. 1.5 × as long as wide.

Fifth leg (Fig. 13K ) shape, segmentation, and armature formula as in C. busanensis , but first segment without inner spinules and second segment slightly longer (1.5 × as long as first segment and 1.9 × as long as wide); lateral spine ca. 1.3 × as long as second segment and nearly 1.8 × as long as medial spine.

Sixth leg (Fig. 12F ) as in C. busanensis .

Male unknown.

Variability.

Only two females were examined, both partly damaged, one in detail with a light microscope (holotype), and the other with a scanning electron microscope (paratype), so variability could not be properly assessed. However, the paratype female was also beforehand examined with a light microscope (although without dissection) and no variability was observed in the most important diagnostic characters (caudal rami length, antennula segmentation, swimming legs armature, or fifth leg proportions); mouth appendages could not be examined without dissection.

Figures

Figure 11. Cyclopina koreana sp. nov., line drawings A-E holotype female F-H allotype male: A third endopodal segment of first swimming leg B third exopodal segment of first swimming leg C third exopodal segment of second swimming leg D third endopodal segment of second swimming leg E fourth swimming leg F antennula G third endopodal segment of fourth swimming leg H third exopodal segment of fourth swimming leg.

Figure 12. Cyclopina curtijeju sp. nov., paratype female, SEM photographs, all in lateral view A anterior part of cephalothoracic shield B posterio-lateral corner of cephalothoracic shield C tergite of second pedigerous somite D tergites of third and fourth pedigerous somites E genital double-somite F sixth leg G fourth and fifth urosomites H sixth urosomite and caudal rami.

Figure 13. Cyclopina curtijeju sp. nov., holotype female, line drawings A caudal ramus, lateral view B distal part of antennula, without armature C coxa of mandibula D endopod of maxillula E endopod of maxilla F endopod of maxilliped G third exopodal segment of first swimming leg H third endopodal segment of first swimming leg I basis and endopod of second swimming leg J fourth swimming leg K fifth leg.

Figure 17. Light photographs of four new species (not to scale) A Cyclopina busanensis sp. nov., four females (two ovigerous) B Cyclopina koreana sp. nov., three females and four males C Cyclopina curtijeju sp. nov., two females D Cyclopina wido sp. nov., two females (one ovigerous) and one male.