Kelleria phuketensis, Kim, 2021

Kim, Jae-Sang Hong and Il-Hoi, 2021, Copepods of the family Kelleriidae (Crustacea, Copepoda, Cyclopoida) from tropical waters of the Asia-Pacific, Journal of Species Research 10 (4), pp. 364-386 : 376-379

publication ID	https://doi.org/ 10.12651/JSR.2021.10.4.364
persistent identifier	https://treatment.plazi.org/id/2549878E-FFFE-FF97-FC8D-FD900661F9D2
treatment provided by	Felipe
scientific name	Kelleria phuketensis
status	sp. nov.

Treatment

Kelleria phuketensis n. sp. ( Figs. 9 View Fig , 10 View Fig )

Material examined. 6 ŞŞ from intertidal invertebrate burrows (inhabited mainly by shrimp and polychaetes), Ko Sireh , Phuket, Thailand, approximately 7°52′26″N, 98°25′235″E, 12 July 2015, I.-H. Kim & J.-S. Hong. Holotype (Ş, MABIK CR00247451 ) and paratypes (4 ŞŞ, MABIK CR00247452 ) have been deposited in the Marine Biodiversity Institute of Korea ( BABIK), Seocheon, Korea. Dissected paratype (1 Ş) is retained in the collection of IHK.

Female. Body ( Fig. 9A View Fig ) rather narrow. Body length 0.95 mm. Prosome 600 μm long, occupying 63% of body length. Maximum width of prosome 356 μm. Dorsal suture line between cephalosome and first pedigerous somite faint. Epimera of second pedigerous somite slightly extended posterolaterally, with blunt posterolateral corners. Urosome ( Fig. 9B View Fig ) 5-segmented. Fifth pedigerous somite 114 μm wide, distinctly narrower than genital double-somite. Genital double-somite as long as wide (134 × 136 μm), consisting of laterally expanded anterior two-thirds and narrower posterior third. Genital apertures large, positioning dorsolaterally at anterior expanded region. Three free abdominal somites 31 × 64, 24 × 56, and 42× 56 μm, respectively. Genital double-somite and first 2 free abdominal somites with membranous fringe along posterior border ( Fig. 9C View Fig ). Anal somite ( Fig. 9C View Fig ) with minute spinules along posteroventral margin. Caudal ramus ( Fig. 9C View Fig ) 3.21 times longer than wide (77 × 24 μm), bearing small pore at distal apex, armed with 6 setae; lateral seta (seta II) positioning at midlength of ramus; lateral and dorsal setae (setae II and VII) naked, other setae pinnate; 2 mid-terminal setae (setae IV and V) flat- tened, tape-like along proximal two-thirds ( Fig. 9B View Fig ).

Rostrum ( Fig. 9D View Fig ) narrow, tapering, slightly longer than wide, with blunt distal apex. Antennule ( Fig. 9E View Fig ) 255 μm long, 7-segmented; armature formula 4, 13, 6, 3, 4 + aesthetasc, 2 + aesthetasc, and 7 + aesthetasc; all setae thin and naked; aesthetascs setiform. Antenna ( Fig. 9F View Fig ) 4-segmented, consisting of coxobasis and 3-segmented endopod; armature formula 1, 1, 2 + claw, and 5 + 2 claws; claws thin, setiform, geniculate in middle; first and third endopodal segments ornamented with minute spinules along outer margin; third endopodal segment 3.4 times longer than wide (61 × 18 μm).

Labrum ( Fig. 9G View Fig ) with deep posteromedian incision and broad posterolateral lobes. Mandible ( Fig. 9H View Fig ) with elongate, spinulose distal lash, 12 or 13 spinules along inner margin, about 30 teeth along convex outer margin, and tuft of 6 minute spinules on outer side near base of gnathobase. Maxillule ( Fig. 10A View Fig ) armed with 2 large distal and 1 subdistal, pinnate setae, 1 small, naked inner margin seta, and membranous flange along outer margin. Maxilla ( Fig. 9I View Fig ) 2-segmented; proximal segment (syncoxa) unarmed; distal segment (basis) with large, spiniform inner seta (seta I) bearing spinules along both margins, simple, slender anterior seta (seta II), vestigial proximal seta (seta III), short, spiniform distal lash, and 9 spines along distal margin; spines arranged as 4 small, 2 large, and 3 small from proximal to distal. Maxilliped ( Fig. 10B View Fig ) 3-segmented; first segment (syncoxa) unarmed; second segment (basis) with 2 large setae, proximal seta bearing 3 spinules at proximal region of proximal margin and row of numerous spinules along distal margin, distal seta distinctly longer than proximal seta, with fine spinules along both margins; third segment (endopod) small, terminating in elongated apical seta, with small, naked outer seta, setulelike inner proximal seta, and pinnate inner distal seta.

Legs 1-3 with 3-segmented rami ( Fig. 10C- E View Fig ). Leg 4 ( Fig. 10F View Fig ) with 3-segmented exopod and 1-segmented endopod; endopodal segment 3.71 times longer than wide (63 × 17 μm), bearing small cusp on outer margin; outer and inner distal spines 36 and 55 μm long, respectively; inner seta not extending to distal margin of endopodal segment. Inner coxal seta of leg 4 rudimentary and naked, all other setae on legs 1-4 pinnate. Armature formula for legs 1-4 as in the type species of the genus, Kelleria regalis .

Leg 5 consisting of 1 naked dorsolateral seta on fifth pedigerous somite and free exopod ( Fig. 9B View Fig ); exopodal segment ( Fig. 10G View Fig ) elongate, nearly rectangular, 3.69 times longer than wide (59 × 16 μm), armed distally with 1 spine (39 μm long) and 1 naked setae (41 μm long); small patch of minute spinules present at distal third of outer surface of exopodal segment. Leg 6 ( Fig. 10H View Fig ) represented by 1 small spinule, 1 cusp, and 1 posterolaterally separated pinnate seta in genital aperture.

Male. Unknown.

Etymology. The new species is named after the type locality, Phuket Island, Thailand.

Remarks. In seven species of Kelleria the exopodal segment of female leg 5 has a smooth inner margin without any process and in ten species of the genus the exopod of female leg 5 is armed distally with one spine and one seta (rather than two setae). Both of these features are possessed in common by Kelleria phuketensis n. sp. and its four congeners, Kelleria portiviva Kim, 2006 , Kelleria undecidentata Kim, 2006 , Kelleria vaga , and Kelleria latipes n. sp. The latter four species can be differentiated from Kelleria phuketensis n. sp. by different features of the female, which are not applicable to the new species, as follows:

In Kelleria undecidentata the genital double somite is distinctly longer than wide, 148 × 121 μm ( Kim, 2006), the rostrum is angular at apex, the basis of the maxilla bears 11 spines along its distal margin, and the exopodal segment of leg 5 is 4.66 times longer than wide (79 × 17 μm) ( Kim, 2006).

In Kelleria vaga the caudal ramus is 4.76 times longer than wide (100 × 17 μm), the exopodal segment of leg 4 is 3.3 times longer than wide (50 × 15 μm) with its distal spine and seta of unequal lengths, 31 and 45 μm, respectively, and the mandibular gnathobase has a row of spinules (rather than a tuft of spinules, as in Kelleria phuketensis n. sp.) on the outer side ( Kim, 2000).

In Kelleria latipes n. sp. the exopodal segment of leg 5 is lamellate, broad, 1.88 times longer than wide, the proximal seta on the second segment (basis) of the maxilliped is naked along its proximal margin, and the mandibular gnathobase has a row of about 10 long spinules on the outer side.

Kelleria phuketensis n. sp. is very similar to Kelleria portiviva . Major differences are exhibited in the proportional lengths of the genital double-somite, caudal ramus, and setal elements on leg 5, as shown in Table 1.