Laophontodes monsmaris, George, 2018

George, Kai Horst, 2018, Laophontodes typicus T. Scott (Copepoda, Harpacticoida, Laophontodinae) - discovering a species complex by morphology, European Journal of Taxonomy 439, pp. 1-43 : 26-30

publication ID	https://doi.org/ 10.5852/ejt.2018.439
DOI	https://doi.org/10.5281/zenodo.6486187
persistent identifier	https://treatment.plazi.org/id/03E55261-2260-FFE4-6E40-FB5068DD53A5
treatment provided by	Plazi
scientific name	Laophontodes monsmaris
status	sp. nov.

Treatment

Laophontodes monsmaris sp. nov.

urn:lsid:zoobank.org:act:CCE6A44F-6FBC-4F32-A18D-33244AA07160

Figs 16–20 View Fig. 16 View Fig. 17 View Fig. 18 View Fig. 19 View Fig. 20

Etymology

The specific epithet is derived from the Latin 'mons' (mount) and 'maris' (from the sea), in reference to the seamount type locality.

Type material

The specimens were originally assigned to Laophontodes typicus by George & Schminke (2002).

Holotype GoogleMaps

ATLANTIC OCEAN: ♂, upper slope of the north eastern plateau of the Great Meteor Seamount GoogleMaps , 30°05.9′ N, 28°24.3′ W, station #521 GoogleMaps , depth 422 m, research cruise M42/3 of German RV METEOR (1998), 14 Sep. 1998, Dr Nils Brenke leg. ( SMF 37120/1–2 , on 2 slides).

Allotype

ATLANTIC OCEAN: ♀, same locality as for holotype ( SMF 37121/1, on 1 slide). GoogleMaps

Paratypes

ATLANTIC OCEAN: 5 ♂♂, same locality as for holotype ( SMF 37123/1 , SMF 37124/1 , SMF 37125/1 , SMF 37126/1 , SMF 37127/1 ; on 5 slides) GoogleMaps ; 1 ♀, upper slope of the Great Meteor Seamount 30°06.0′ N, 28°24.3′ W, station #520 , depth 511 m, research cruise M42/3 of German RV METEOR (1998) ( SMF 37122/1 , on 1 slide) GoogleMaps ; copepodid CV, same locality as for holotype ( SMF 37128/1 , on 1 slide); GoogleMaps copepodid CV, same locality as for holotype ( SMF 37129/1 , on 1 slide). GoogleMaps

Description

Female

HABITUS ( Fig. 16A View Fig. 16 ). Cylindrical, body length (R to end of FR) 305–317 µm (n = 2). Cphth slightly longer than broad, ⅓ of total body length, posteriorly slightly bulged laterally; dorsally, 2 cuticular longitudinal ridges run towards but do not reach posterior margin. R small, fused to cphth, with 2 sensilla and 1 tube pore on apical margin. Body somites clearly distinct. Last thoracic and first abdominal somite fused to form GDS, juncture detectable by dorsal serration. Posterior margin of body somites, except penultimate somite, with row of fine setules; cphth, thoracic somites (except P5-bearing somite) and abdominal part of GDS with 1 pair of sensilla arising from small cuticular socles. First 3 free thoracic somites and abdominal part of GDS additionally with tooth-like cuticular projections, remaining somites dorsally serrated on posterior margin. P2–P5-bearing somites and thoracic part of GDS additionally with 1 tube pore centrally. Thoracic and Abdominal subunits of GDS with pair of tube pores; abdominal subunit additionally with serrated posterior margin. Second and third abdominal somites also with paired tube pores. Penultimate somite without sensilla or tube pores. Telson slightly smaller than preceding somite and mostly overlapped by it, with FR widely separated proximally. Anal operculum with pair of sensilla and with spinulose apical margin.

FURCAL RAMI ( Fig. 16A–B View Fig. 16 ). Slender, about 5 times longer than its broadest part, proximally with tube pore, and with 7 setae: I and II central on outer margin, II twice as long as I; III subapical on outer margin; IV and V apical, IV half of the length of V; VI apical on inner margin, slightly longer than III; VII dorsal, arising from pedestal, tri-articulated at base.

ANTENNULE ( Fig. 17A View Fig. 17 ). 5-segmented. First segment with 1 bipinnate seta and some spinules apically; second segment without ‘bump’ on posterior margin, corresponding area covered with long spinules, distally with 9 bare setae; third segment as long as previous segments, with 7 bare setae and 1 aes; fourth segment smallest, partially overlapped by third segment, with 1 bare seta; fifth segment with 9 bare setae and apical trithek formed by 1 small aes and 2 bare setae.

SETAL FORMULA. 1-1/2-9/3-7+aes/4-1/5-11+aes.

A2, MXL AND MX. Described from male.

MANDIBLE ( Fig. 17B View Fig. 17 ). Gnathobase bearing 5 teeth; palp 1-segmented, with 5 bare setae.

MAXILLIPED ( Fig. 17E View Fig. 17 ). Very large (cf. Fig. 16C View Fig. 16 ); syncoxa cylindrical, without spinules or setal elements; basis longer than syncoxa, also lacking ornamentation; enp produced into long, slender claw and accompanied by 1 minute seta at its base.

SWIMMING LEGS. P1 ( Fig. 18A View Fig. 18 ) coxa elongate; basis as long as coxa, with 1 bipinnate outer and inner seta, the latter displaced to anterior surface. Enp 2-segmented, enp-1 strong and elongate, with row of spinules on outer and the inner margins, inner spinules 2–3 times longer than outer spinules; enp-2 small, less than ⅓ length of enp-1, apically with 1 claw, 1 slender geniculate bare seta and 1 small subapical seta. Exp 3-segmented, less than ½ length of enp-1. Exp-1 with scant spinules and 1 uniplumose spine on outer margin; exp-2 with outer and inner spinules and 1 long bare geniculate outer seta; exp-3 with some outer spinules and 4 long bare geniculate setae. P2–P4 ( Figs 18B View Fig. 18 , 19A–B View Fig. 19 ) with transversely elongated bases, 3-segmented exopods and 2-segmented endopods. All exopodal segments with a row of spinules on outer margin, exp-1 and exp-2 additionally with fine spinules sparsely on inner margins and 1 bipinnate outer spine; exp-1 without, exp-2 with 1 inner seta; exp-3 longest segment, with 3 bipinnate outer spines and 2 bipinnate apical setae, additionally P2 exp-3 ( Fig. 18B View Fig. 18 ) with 1 inner seta, P3 and P4 exp-3 ( Fig. 19B View Fig. 19 ) with 2 inner setae. P2–P4 enp-1 small, without setae. Enp-2 elongated, with inner and outer spinules and 2 biplumose apical setae in P2 and P3 ( Figs 18B View Fig. 18 , 19A View Fig. 19 ) and 1 additional bare seta in P4 ( Fig. 19B View Fig. 19 ). P5 ( Fig. 18C View Fig. 18 ) benp reduced to 2 setae, one bipinnate and one apically biplumose; tube pores not discernible. Setophore on outer apical margin accompanied by long spinules and 1 tube pore and carrying 1 bare seta. Exp fused to benp, slender, carrying 3 outer seta, one of which bipinnate, the others bare, and 2 apical bipinnate setae; additionally with small tube pore and spinules subapically.

GENITAL FIELD. Not drawn, almost identical to that in Laophontodes sarsi sp. nov.

Male

The male differs remarkably from the female in terms of body ornamentation and missing GDS. Further differences can be observed in A1, P3 and P4 endopods, and P5. Note that the A2, mxl, and mx are described from the male being obscured/damaged in the female.

HABITUS ( Fig. 16C View Fig. 16 ). Same length as female (body length, R–FR: 300–317 µm; n = 3). Cephalothoracic longitudinal cuticular ridges absent, as are the sensillar socles, serrated posterior margins, and toothlike cuticular projections on the body somites. As in female fine setules on posterior margins of body somites, and additionally on penultimate body somite. As in female T mostly overlapped by the previous abdominal somite. FR slightly smaller and more compact relative to female.

ANTENNULE ( Fig. 20A View Fig. 20 –A’). 6-segmented, chirocer. First segment as in female apically with 1 bipinnate seta and scant spinules; second segment without ‘bump’ or corresponding long spinules, with 9 bare setae; third segment with 7 bare setae; fourth segment minute, with 2 bare setae; fifth segment swollen, with 10 bare setae plus 1 strongly sclerotized bare spine, additionally with 1 aes and 1 accompanying seta arising together from pedestal; sixth segment bent and tapering distally, with 8 bare setae, and 1 small aes and 2 bare setae forming trithek.

SETAL FORMULA. 1-1/2-9/3-7/4-2/5-12+aes/6-10+aes.

ANTENNA ( Fig. 20B View Fig. 20 ). Allobasis with 1 bare abexopodal seta and scant spinules; exp represented by small bare seta; enp slightly smaller than allobasis, anteriorly with row of spinules, 2 bipinnate distal setae and 2 bare and 3 geniculated apical setae, outermost apical seta accompanied by minute tube pore, additionally with cuticular dentate frill.

MAXILLULE ( Fig. 17C View Fig. 17 ). Praecoxal arthrite not described. Coxa unarmed, apically with 2 bare setae; basis without spinules, terminally with 3 bare setae, laterally with 1 bipinnate seta between basal endite and enp. Exp represented by 2, enp represented by 3 bare setae.

MAXILLA ( Fig. 17D View Fig. 17 ). Syncoxa bearing 1 row of spinules and 2 endites. Proximal and distal endites each with 3 bare setae. Basis distinct, produced into strong claw, with 2 bare setae. Enp 1-segmented, minute, with 2 bare setae.

SWIMMING LEGS. P3 ( Fig. 19C View Fig. 19 ) exp as in female; enp 3-segmented; enp-1 minute and unarmed; enp-2 longest, with row of spinules on inner and outer margins, without setal elements but with apical apophysis not reaching apical margin of enp-3; enp-3 ¼ length of enp-2, with 2 biplumose apical setae. P4 ( Fig. 19D View Fig. 19 ) exp as in female; enp 2-segmented; enp-1 minute and unarmed; enp-2 with row of spinules on inner and outer margins, 1 bare outer setae, 1 biplumose inner seta and 2 biplumose apical setae. P5 ( Fig. 20C View Fig. 20 ) benp small with 1 outer seta arising from elongated setophore; endopod virtually absent, represented by 1 bipinnate seta longer than exp. Exp fused to benp, with 1 outer bipinnate, 1 subapical bare, and 2 apical bipinnate setae.