Kelleria latipes, 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 : 373-376

publication ID	https://doi.org/ 10.12651/JSR.2021.10.4.364
persistent identifier	https://treatment.plazi.org/id/2549878E-FFFB-FF94-FCE3-FDD007E9FDCA
treatment provided by	Felipe
scientific name	Kelleria latipes
status	sp. nov.

Treatment

Kelleria latipes n. sp. ( Figs. 7 View Fig , 8 View Fig )

Material examined. 7 ŞŞ from intertidal invertebrate burrows (inhabited mainly by shrimps 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 CR00247449 ) and paratypes (5 ŞŞ, MABIK CR00247450 ) have been deposited in the Marine Biodiversity Institute of Korea ( MABIK), Seocheon, Korea. Dissected paratype (1 Ş) is retained in the collection of IHK.

Female. Body ( Fig. 7A View Fig ) narrow. Body length 981 μm in dissected specimen. Mean body length 1.03 mm (0.98- 1.10 mm, n = 6). Prosome 636 μm long, occupying 65% of body length. Cephalothorax longer than wide (395 × 345 μm), with faint dorsal suture line between cephalosome and first pedigerous somite; posterolateral corners not projected. Second pedigerous somite with slightly angular posterolateral corners. Lateral corners of other prosomal somites rounded or blunt. Urosome ( Fig. 7B View Fig ) 5-segmented. Fifth pedigerous somite 103 μm wide. Genital double-somite wider than long (117 × 130 μm), consisting of laterally expanded anterior and narrower posterior parts; genital apertures large, positioning dorsolaterally at expanded anterior part. Three free abdominal somites 38 × 65, 30 × 59, and 40 × 58 μm, respectively. Anal somite 1.33 times longer than second free abdominal somite. Caudal ramus ( Fig. 7C View Fig ) 2.52 times longer than wide (68 × 27 μm), 1.70 times longer than anal somite, armed with 6 setae, bearing small pore at distal apex; lateral seta (seta II) and dorsal seta (seta VII) naked, other 4 setae pinnate; lateral seta positioning at midway of ramus length; 2 mid-terminal setae (setae IV and V) broadly flat- tened, tape-like, along proximal two-thirds.

Rostrum ( Fig. 7D View Fig ) narrow, tapering, with blunt distal apex. Antennule ( Fig. 7E View Fig ) 255 μm long, 7-segmented; armature formula 4, 13, 6, 3, 4 + aesthetasc, 2 + aesthetasc, and 7 + aesthetasc; setae naked and thin; aesthetascs setiform. Antenna ( Fig. 7F View Fig ) 4-segmented, consisting of coxobasis and 3-segmented endopod; armature formula 1, 1, 2 + claw, and 5 + 2 claws; claws slender, geniculate in middle; first and third endopodal segments ornamented with minute spinules along outer margin; third endopodal segment 3.58 times longer than wide (68 × 19 μm).

Labrum ( Fig. 7G View Fig ) with deep posteromedian incision and broad posterolateral lobes bearing round posterior margin. Mandible ( Fig. 7H View Fig ) with elongate, spinulose distal lash, row of about 10 thin spinules at convex side, 16 elongate spinules (grouped as 10 and 6) on inner margin, about 15 teeth along convex outer margin of gnathobase, and narrow membranous flange along proximal outer margin. Maxillule ( Fig. 7I View Fig ) armed with 4 setae consisting of 2 longer, weakly pinnate distal setae, smallest subdistal inner seta, and process-like inner margin seta; outer margin fringed with narrow membrane along distal third. Maxilla ( Fig. 7J View Fig ) with unarmed syncoxa; basis with spiniform distal lash, large, spiniform inner seta (seta I) bearing spinules along both margins, slender, naked anterior seta (seta II), and 9 or 10 spines along distal margin (arranged as 2 small, 3 large, 4 or 5 small ones from proximal to distal); seta III not discernible. Maxilliped ( Fig. 8A View Fig ) 3- segmented; first segment (syncoxa) unarmed; second segment (basis) with protruded inner margin bearing 2 large setae, proximal seta with dense row of thin spinules along distal margin, distal seta longer than proximal seta, bearing dense row of fine spinules along both margins; small third segment (endopod) terminating in elongate, whiplike apical seta, with small, pinnate outer and inner distal setae, and minute inner proximal setule.

Legs 1-3 with 3-segmented rami ( Fig. 8B- D View Fig ). Leg 4 ( Fig. 8E View Fig ) with 3-segmented exopod and 1-segmented endopod. All setae on these legs pinnate. Leg 4 endopodal segment 3.1 times longer than wide (56 × 18 μm), extending to distal border of second exopodal segment, with small cusp on outer margin; 2 distal spines 42 (outer) and 55 (inner) μm long; inner margin seta extending to distal margin of segment. Armature formula for legs 1-4 as in Kelleria regalis .

Leg 5 consisting of dorsolateral seta on fifth pedigerous somite and free exopod; exopodal segment ( Fig. 8F View Fig ) broad, broadening distally, 1.88 times longer than wide (62 × 33 μm) armed distally with 1 spinulose spine (43 μm long) and 1 pinnate, geniculate seta (47 μm long), and ornamented with numerous spinules on surfaces of distal half of segment. Leg 6 ( Fig. 8G View Fig ) represented by 1 small seta, 1 small cusp, and posterolaterally isolated, weakly pinnate seta in genital aperture.

Male. Unknown.

Etymology. The specific name is a combination of the Latin words lat (= broad) and pes (= a foot), depicting the broad exopodal segment of female leg 5.

Remarks. Kelleria latipes n. sp. may be differentiated from its congeners by two ways, as follows:

The proximal seta on the second segment (basis) of the female maxilliped is ornamented with spinules or setules along its distal margin, but naked, unornamented along its proximal margin. This form of the seta (with naked proximal margin) is shared by four congeners, Kelleria andamanensis Sewell, 1949 , Kelleria gradata Stock, 1967 , Kelleria indonesiana Mulyadi, 2009 , and Kelleria multioviger Kim, 2009 . Of these, Kelleria andamanensis , Kelleria gradata , and Kelleria multioviger are not confusable with the new species, because these species have the exopod of leg 5 armed with 2 setae, in contrast to the armature of 1 spine and 1 seta in the new species. Kelleria indonesiana has a large process on the inner margin of the exopodal segment of leg 5, which is absent in the new species, thus is easily distinguished from the new species.

In most species of Kelleria the genital double-somite of the female is longer than wide. In contrast, the double-somite of Kelleria latipes n. sp. is wider than long and only three congeners, Kelleria gradata , Kelleria multioviger , and Kelleria vaga Kim, 2000 share this form of the genital double-somite with Kelleria latipes n. sp. The new species can readily be distinguished from the three congeners by the form of the caudal ramus which is 2.52 times longer than wide, against to 1.90 times longer than wide in Kelleria gradata , according to Stock (1967) who described the size of its caudal ramus as 91 μm long and 48 μm wide, 1.80 times longer than wide in Kelleria multioviger , according to Kim (2009), and 4.76 times longer than wide in Kelleria vaga , as described by Kim (2000).

The characteristic form of the exopodal segment of female leg 5, which is broad, without any process or cusp, alone may characterize the new species.