Alupa geminata, Kim & Boxshall, 2021

Kim, Il-Hoi & Boxshall, Geoff A., 2021, Copepods associated with Ascidian hosts (Tunicata): Intramolgidae and Lichomolgidae, with descriptions of four new genera and 13 new species, Zootaxa 5013 (1), pp. 1-75 : 61-64

publication ID	https://doi.org/ 10.11646/zootaxa.5013.1.1
publication LSID	lsid:zoobank.org:pub:BBB1CB11-1AEA-4678-8F6C-B43B7F35E453
persistent identifier	https://treatment.plazi.org/id/8D4A87BF-FF87-FFB1-FF19-FC5C9F34F9B0
treatment provided by	Plazi
scientific name	Alupa geminata
status	gen. et sp. nov.

Treatment

Alupa geminata gen. et sp. nov.

( Figs. 38 View FIGURE 38 , 39 View FIGURE 39 )

Type material. Holotype ♀ (MNHN-IU-2014-21607, intact), paratype ♀ (MNHN-IU-2014-21493, dissected) from ieptoclẚnẚdes madara Tokioka , 1953 (MNHN-IT-2008-4797 = MNHN A2 About MNHN /LEP/73): Palau (07°30.58´N, 134°29.66´E), OCDN 3954-1 , depth 0.5 m, CRRF coll., 11 June 1996. GoogleMaps

Etymology. The specific name is derived from the Latin gem ẚn (=twin), indicating that it was described on the basis of two specimens.

Description of female. Body ( Fig. 38A View FIGURE 38 ) rather narrow; body length 891 μm; prosome 482×316 μm. Cephalot- horax with round anterior and lateral margins and faint dorsal suture line delimiting cephalosome and first pedigerous somite. Epimera of second pedigerous somite with slightly produced posterolateral corners. Urosome ( Fig. 38B View FIGURE 38 ) 5-segmented; fifth pedigerous somite 120 μm wide. Genital double-somite slightly longer than wide (136×124 μm), with laterally expanded anterior two-thirds and narrower posterior third; genital apertures positioned dorsolaterally at about 40% of length of double-somite; broader anterior part with angular posterolateral extension on each side. Three free abdominal somites characteristically subequal in length, 71×57, 73×48, and 76×47 μm, respectively, each somite longer than wide. Genital double-somite and abdominal somites with serrate membranous flange along posteroventral margins ( Fig. 38C View FIGURE 38 ). Caudal ramus ( Fig. 39A View FIGURE 39 ) about 3.6 times longer than wide (72×20 μm), rec- tangular, with parallel lateral margins, and ornamented with 5 spinules along posteroventral margin; armed with 6 naked setae, outer lateral seta positioned at 73% of ramus length.

Rostrum ( Fig. 38D View FIGURE 38 ) longer than wide, with subparallel lateral margins and convex posterior margin. Antennule ( Fig. 38E View FIGURE 38 ) 187 μm long, 7-segmented; armature formula 4, 13, 6, 3, 4+aesthetasc, 2+aesthetasc, and 7+aesthetasc; all setae naked; aesthetascs slender, setiform. Antenna ( Fig. 38F View FIGURE 38 ) 4-segmented, consisting of coxobasis and 3-segmented endopod; armature formula 1, 1, 4, and 3+4 claws; terminal segment about twice as long as wide (33×16 μm), with longer outer margin and much shorter inner margin; 4 terminal claws small and annulated (2 thick and 2 slender).

Labrum ( Fig. 38G View FIGURE 38 ) with broad posteromedian incision and narrow posterolateral lobes each tipped with medially directed, digitiform process; posteromedial border with transverse row of spinules. Mandible ( Fig. 38H View FIGURE 38 ) with narrow blade and elongate distal lash; blade and lash ornamented with row of spinules along each margin. Maxillule ( Fig. 38I View FIGURE 38 ) with 1 small seta on inner margin and 2 broad apical spines (or setae bearing membranous flange) of unequal length; larger spine 1.8 times longer than smaller. Maxilla ( Fig. 38J View FIGURE 38 ) consisting of syncoxa and basis; syncoxa unarmed; basis with elongate distal lash and 2 setae; distal lash directed at right angle to proximal part of basis, ornamented with 4 thicker spinules proximally followed by thinner spinules along half of outer margin; inner margin of lash with fine spinules; inner seta (seta I) spiniform, about 0.6 times as long as lash, with 2 rows of spinules along its outer margin; small anterior seta naked. Maxilliped ( Fig. 38K View FIGURE 38 ) 3-segmented; first segment unarmed; second segment with 2 small, unequal setae; terminal segment attenuated, claw-like, proximally with 1 small, spinulelike process and 1 minute seta.

Legs 1, 2 ( Fig. 39B, C View FIGURE 39 ) and 3 with 3-segmented rami. Leg 3 same as leg 2 except third endopodal segment bearing 3 spines and 2 setae ( Fig. 39D View FIGURE 39 ). Leg 4 ( Fig. 39E View FIGURE 39 ) with 3-segmented exopod and small, 2-segmented endopod; endopod slender, less than half length of exopod; proximal endopodal segment unarmed; distal segment with 1 naked seta at apex. Inner coxal seta of legs 1-3 well-developed, pinnate, but that of leg 4 small and naked. Outer seta on basis pinnate in leg 1, but naked in legs 2-4. Outer spines on exopods small. Armature formula for legs 1–4 as follows:

Coxa Basis Exopod Endopod

Leg 1: 0-1 1-0 I-0; I-1; III, I, 4 0-1; 0-1; I, 1, 4

Leg 2: 0-1 1-0 I-0; I-1; III, I, 5 0-1; 0-2; I, II, 3

Leg 3: 0-1 1-0 I-0; I-1; III, I, 5 0-1; 0-2; I, II, 2

Leg 4: 0-1 1-0 I-0; I-1; II, I, 5 0-0; 0, 1, 0

Leg 5 ( Fig. 39F View FIGURE 39 ) consisting of dorsolateral seta on somite and free exopodal segment; exopod with prominent, semicircular inner expansion proximally bearing broad membranous flange along margin; armed with 2 very unequal naked setae distally, inner seta 20 μm long and outer seta 77 μm. Leg 6 ( Fig. 39G View FIGURE 39 ) represented by 1 naked seta, 1 pinnate seta, and 1 denticle on genital operculum.

Male. Unknown.

Remarks. This is the first report of any copepod associated with this host, ieptoclẚnẚdes madara. The host was originally described from Japan and is also known to occur in Australia (originally recorded as iK varẚegatus Kott, 2001) so Palau, the type locality of Alupa gem ẚnata gen. et sp. nov., lies close to the centre of the geographical distribution of the host.

Genus Lobomolgus Ho & Kim I.H., 2009

Diagnosis. As in Ho & Kim I.H. (2009), but with slight emendation as follows: Caudal ramus typically with 7 setae, sometimes reduced. Endopod of leg 4 absent or 1-segmented. Armature formula of last exopodal segment of leg 4 being III, I, 5 or III, 1, 3 in female, and II, I, 5 or II, I, 4 in male. Leg 5 represented by tiny lobe tipped with 2 elements.

Type species. iobomolgus okẚnawaensẚs Ho & Kim I.H., 2009 by original designation.

Remarks. The type species of iobomolgus, i. okẚnawaensẚs was based on specimens found in association with the compound ascidian aẚdemnum molle (Herdmann, 1886) in Okinawa (Ho & Kim I.H, 2009). We describe below a second species associated with the same ascidian host species.