Delamarella obscura, Huys & Karaytuǧ & Cottarelli, 2005

Huys, Rony, Karaytuǧ, Süphan & Cottarelli, Vezio, 2005, On the synonymy of Delamarella Chappuis and Latiremus Bo | ic (Copepoda, Harpacticoida, Latiremidae), including the description of D. obscura sp. nov. from the Black Sea, Zoological Journal of the Linnean Society 145 (3), pp. 263-281 : 264-271

publication ID	https://doi.org/ 10.1111/j.1096-3642.2005.00188.x
persistent identifier	https://treatment.plazi.org/id/B26C3D16-B711-FFE3-B9A3-1219FC4FFBF8
treatment provided by	Diego
scientific name	Delamarella obscura
status	sp. nov.

Treatment

GENUS DELAMARELLA CHAPPUIS, 1954 DELAMARELLA OBSCURA SP. NOV.

Synonym: Delamarella karamani Petkovski, 1957 sensu Apostolov (1969) .

Type locality: Filyos beach, Hisarönü, Zonguldak province (station 14) ( Turkey) .

Type material: Holotype adult ♀ dissected on 3 slides (deposited in NHM, reg. no. 2005.167). Paratypes are (1) 1 adult ♂ dissected on 5 slides (deposited in NHM, reg. no. 2005.168), (2) 4 Cop V ♀♀, 1 Cop IV ♀ and 2 Cop V ♂♂ preserved in alcohol; and 1 adult ♀ dissected on 4 slides (deposited in BU). Collected on 7 July 2001 from type locality; leg. S. Karaytuǧ and S. Sak.

Other material: (1) From Göbü beach, Hisarönü, Zonguldak province (station 12), Turkey (leg. S. Karaytuǧ and S. Sak; 7 July 2001): 4 adult ♀♀ and 1 adult ♂ preserved in alcohol (deposited in NHM, reg. no. 2005.169–173); 3 adult ♀♀, 1 adult ♂, 6 Cop V ♀♀, 2 Cop IV ♀♀, 1 Cop V ♂ all preserved in alcohol, 1 ♂ dissected on 1 slide (deposited in BU); (2) from Türkali beach, Hisarönü, Zonguldak province (station 13), Turkey (leg. S. Karaytuǧ and S. Sak; 7 July 2001): 2 adult ♀♀, 1 adult ♂, 3 Cop V ♀♀ and 1 Cop V ♂ preserved in alcohol (deposited in NHM, reg. no. 2005.174–180); (3) from Kapısuyu beach, Kurusacile, Bartin province (station 17), Turkey (leg. S. Karaytuǧ and S. Sak; 8 July 2001): 4 ♀♀ preserved in alcohol (deposited in NHM, reg. no. 2005.181–185); (4) from Inebolu beach, Inebolu, Kastamonu province, Turkey (leg. S. Karaytuǧ and S. Sak; 8 July 2001): various specimens (deposited in BU) .

Description

Female: Total body length: 420–520 µm (mean = 487 µm; N = 10). Maximum width measured at cephalothorax. P1-bearing somite completely incorporated in cephalosome forming a cephalothorax ( Fig. 1A, B View Figure 1 ). P2-bearing somite separated from cephalothorax by large intersomitic membranous zone. Posterior margin of cephalothorax and pedigerous somites with plain hyaline frill ( Fig. 1A, B View Figure 1 ); hyaline frill of urosomites with denticulate hyaline frill dorsally and ventrally ( Figs 2B View Figure 2 , 3A View Figure 3 ). Rostrum ( Fig. 1A View Figure 1 ) very small, fused to cephalic shield; with 2 delicate sensillae.

Genital somite ( Figs 1A, B View Figure 1 , 2B View Figure 2 ) completely free from first abdominal somite. Genital field ( Figs 3C, G View Figure 3 , 11A View Figure 11 ) small, positioned far anteriorly on midventral surface of genital somite, flanked by 2 pairs of secretory pores; consisting of 2 closely set crescent-shaped opercula derived from P6 and closing off paired genital apertures, without armature; copulatory pore internal (arrowed in Fig. 3G View Figure 3 ). All postgenital somites with transverse spinular rows as illustrated in Figure 2B View Figure 2 ; no distinct ornamentation dorsally. Anal operculum spinulose, with 20–30 small spinules ( Figs 3A View Figure 3 , 7A View Figure 7 ); anal frill deeply serrated, setulose, largely covered by anal operculum ( Fig. 3A View Figure 3 ).

Caudal rami ( Figs 2B View Figure 2 , 3A View Figure 3 , 7A View Figure 7 ) slightly divergent; partly concealed beneath anal operculum; longer than wide; ventral surface with pore near proximal margin and tube-pore subdistally; inner margin with row of fine long setules running on to dorsal surface; dorsal surface with oblique row of strong spinules, increasing in size abaxially; posterior margin smooth dorsally, with strong spinules ventrally. Ramus with 7 setae: seta I relatively well developed; setae II and III spiniform and finely pinnate, with subapical flagellate extension; setae IV and V well developed, bipinnate, with fracture planes; seta VI short and bare; seta VII plumose and tri-articulate at base.

Antennule short ( Fig. 1A, B View Figure 1 ), typically 9-segmented ( Fig. 3E View Figure 3 ) but boundaries between segments 7 and 9 frequently not clearly expressed ( Fig. 8A View Figure 8 ); segment 1 with pinnate seta near anteriolateral corner. Armature formula: 1-[1], 2-[7 + 2 pinnate], 3-[6], 4- [3 + (1 + ae)], 5-[2], 6-[3 + 1 pinnate], 7-[2], 8-[2], 9-[6 + (1 + ae)].

Antenna ( Fig. 3F View Figure 3 ) consisting of coxa, basis, 1- segmented exopod and 2-segmented endopod; basis and proximal endopod segment incompletely separated. Coxa with spinules along distal margin. Basis and proximal endopod segment incompletely fused, original boundary being represented by surface furrow ( Fig. 8B View Figure 8 ) but not by functional articulation; each segment with bipinnate seta. Free endopod with spinules along abexopodal margin; lateral armature consisting of 2 pinnate spines and 1 seta ( Fig. 3F View Figure 3 : inset); distal armature consisting of 1 simple and 4 geniculate setae, longest one of which fused basally to long sparsely pinnate seta. Exopod 1-segmented; with 3 curved unipinnate spines laterally and 1 strong pinnate spine apically.

Mandible ( Figs 4A View Figure 4 , 9A View Figure 9 ) with well-developed gnathobase provided with series of small, curved teeth and pinnate seta at dorsal corner. Palp uniramous, consisting of basis and endopod. Basis with 1 naked and 2 pinnate setae. Endopod 1-segmented, with 2 lateral and 6 terminal setae.

Labrum well developed, with transverse spinule row along free ventral margin and median tuft of setules on anterior surface ( Fig. 8C View Figure 8 ).

Maxillule ( Fig. 4B View Figure 4 ). Praecoxal arthrite with 2 tubesetae on anterior surface; distal margin with 8 strong spines. Coxal endite with 2 naked setae and 1 geniculate spine. Basis with 2 geniculate, 2 bipinnate and 3 naked setae. Endopod and exopod defined at base, with 3 naked setae each.

Maxilla ( Figs 4C–D View Figure 4 , 9B View Figure 9 ). Syncoxa with 3 endites and 2 spinular rows; proximal endite with 4 setae, middle endite with 2 setae and large backwardly directed unipinnate spine, distal endite with 1 naked and 2 pinnate setae; posterior surface with slit-like opening of maxillary gland (arrowed in Fig. 9B View Figure 9 ). Allobasis with 2 naked setae and 2 serrate spines. Endopod 2-segmented; enp-1 with 2 serrate spines; enp-2 with 1 serrate spine and 3 naked setae.

Maxilliped ( Figs 4E View Figure 4 , 9C View Figure 9 ) prehensile, comprising syncoxa, basis and 1-segmented endopod. Syncoxa with 3 spinular rows and 1 pinnate seta. Palmar margin of basis with row of strong spinules anteriorly, row of finer spinules posteriorly and 2 setae (smaller one with tubular extension; arrowed in Fig. 4E View Figure 4 ). Endopod with small sclerite at base; drawn out into strong, curved claw bearing 3 accessory setae.

P1 ( Figs 5A View Figure 5 , 9D View Figure 9 , 10A, B View Figure 10 ). Protopod with accessory sclerite positioned dorsally to praecoxa (arrowed in Fig. 9D View Figure 9 ). Praecoxa represented by a well-developed sclerite with spinular row on anterior surface. Coxa with spinular row anteriorly and posteriorly as figured. Intercoxal sclerite with fine spinular rows anteriorly. Basis with pinnate spine (with subapical flagellate extension) at outer distal corner and inner unipinnate spine; anterior surface with strong spinules around distal margin. Exopod 3-segmented; exp-1 and -2 with outer unipinnate spine and covered with coarse spinules around outer and distal margins; exp-3 small, with 2 unipinnate geniculate spines and 2 long bare setae; boundary between exp-2 and -3 not always clearly defined ( Fig. 10B View Figure 10 ) but more clearly expressed when exp-3 withdrawn into exp-2 ( Fig. 10A View Figure 10 ). Endopod 2-segmented; enp-1 elongate, about twice longer than wide, with serrate inner seta, outer and distal margins spinulose; enp-2 very small, with geniculate claw and very long naked seta apically.

P2–P4 ( Fig. 5B–D View Figure 5 ) with 3-segmented exopods and endopods. Intercoxal sclerites with concave ventral margin, without surface ornamentation. Praecoxa represented by well-developed sclerite with anterior spinular row. Coxa with spinular row on posterior surface. Basis with pinnate outer seta (P3–P4) or flagellate outer spine (P2). Exopods longer than endopods. Exopodal segments with coarse spinules along outer and distal margins and without spinules/setules along inner margin. Endopodal segments with coarse spinules along outer (enp-1,2) and distal (enp-1,2,3) margins. P2–P3 ( Fig. 5B, C View Figure 5 ) with serrate inner seta on enp-1 and -2; distal margin of enp-3 with outer pinnate spine and inner plumose seta. P4 enp-1 ( Fig. 5D View Figure 5 ) expanded, with robust unipinnate spine at inner subdistal corner; enp-2 without any spines or setae; enp- 3 with 2 pinnate spines apically.

P1–P4 armature formula:

Exopod Endopod P1 0.0.022 1.020

P2 0.1.022 1.1.020 P3 0.1.022 1.1.020 P4 0.0.022 [modified in ♂] 1.0.020

P5 ( Figs 2B View Figure 2 , 3C View Figure 3 ). Fifth pair of legs fused medially; baseoendopod and exopod forming a common plate; basal seta plumose, arising from a prominent setophore. Exopodal lobe with 2 long biserrate spines, 1 short spinulose spine and 1 bare seta; endopodal lobe with a strong serrate spine medially and 2 short spinulose spines.

Male: Total body length: 440–500 µm (mean = 471 µm; N = 4). Sexual dimorphism in antennule, caudal rami and P4–P6.

Antennule ( Figs 6A–C View Figure 6 , 8D View Figure 8 ) haplocer with 5 segments distal to geniculation; indistinctly 13- segmented; boundaries between segments 11 and 13 expressed only dorsally ( Fig. 6A View Figure 6 ), completely fused ventrally ( Fig. 8D View Figure 8 ). Segment 5 small, represented by small U-shaped sclerite. Segment 6 with long aesthetasc fused basally to seta. Segment 8 with denticulate anteriodorsal margin, 1 naked seta, 1 basally fused pinnate seta (with tubular extension) and 1 modified element. Segment 9 with 3 modified elements. Segments 11–13 forming claw-like compound segment with most setae arranged around posterior margin ( Fig. 8D View Figure 8 ). Armature formula 1-[1 pinnate], 2-[1], 3-[8], 4-[6], 5-[1 + 1 pinnate] 6-[4 + 1 pinnate + (1 + ae)], 7-[2], 8-[1 + 1 pinnate + 1 modified], 9-[3 modified], 10-[1], 11-[2], 12-[2], 13-[5 + (2 + ae)]. Modified elements on segments 8 and 9 with longitudinally ribbed surface and fused basally to segment ( Fig. 8D View Figure 8 ).

Caudal rami ( Figs 2A View Figure 2 , 3D View Figure 3 ) with large cup-shaped pore ventrally halfway along ramus length (arrowed in Fig. 3D View Figure 3 ).

P4 ( Figs 6D View Figure 6 , 10C View Figure 10 ) with strongly modified exopod; exp-1 and -2 expanded, exp-3 reduced forming clawlike segment. Exp-1 rectangular, about 1.4 times as long as maximum width, with long unipinnate outer spine; distal margin and outer distal corner with strong spinules. Exp-2 forming central socket for exp- 3; outer distal corner produced into lobate process (B) and spiniform outgrowth (D); outer spine strongly reduced, represented by small triangular element arising from posterior surface (A). Exp-3 outwardly recurved (C), forming functional grasping device with exp-2; with 3 setiform elements arranged around the inner margin. Endopod relatively longer and more slender than in ♀ enp-1 not expanded as in ♀ and lacking inner spine; outer distal spine on enp-3 comparatively longer than in ♀.

P5 ( Figs 2A View Figure 2 , 6E View Figure 6 , 7D View Figure 7 , 10D View Figure 10 , 11B View Figure 11 ) essentially as in ♀ except middle endopodal spine relatively longer and with smaller hyaline flanges.

Sixth pair of legs ( Figs 2A View Figure 2 , 11B View Figure 11 ) strongly asymmetrical, with both members fused to genital somite and bearing 1 short bare and 1 long plumose seta; largest member functional one, inner portion rounded and with denticulate free margin. Spermatophore moderately large, about 80 µm.

Etymology. The specific epithet alludes to the small differences between the new species and its mediterranean congeners.