Paramphiascella dahmsi, Chullasorn, Supawadee, 2010

Chullasorn, Supawadee, 2010, Two new species of Paramphiascella Lang (Copepoda: Harpacticoida: Miraciidae) from a brackish water pond in Thailand, Zootaxa 2634, pp. 1-24 : 2-12

publication ID	https://doi.org/ 10.5281/zenodo.198371
DOI	https://doi.org/10.5281/zenodo.5676732
persistent identifier	https://treatment.plazi.org/id/0F3887AA-FFE6-FFCD-FF5F-F90BFE4BEB06
treatment provided by	Plazi
scientific name	Paramphiascella dahmsi
status	sp. nov.

Treatment

Paramphiascella dahmsi sp. nov.

( Figs 1–8 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 )

Type material. Dissected female holotype ( USNM 1132870), dissected male allotype ( USNM 1132871), one female paratype ( USNM 1132872), one male paratype ( USNM 1132873). The type material is deposited in the National Museum of Natural History, Smithsonian Institution, Washington DC, USA. The type specimens were collected on 22 September 2002.

Type locality. Brackish water pond, Coastal Fisheries Research Development Center, Department of Fisheries, Samut Sakhon province, Thailand (13°32'N, 100°16'E).

Etymology. The specific name honors Dr. Hans-Uwe Dahms, Professor at Sangmyung University, Seoul, for his achievements in the study of copepods. The name is a noun in the genitive singular.

Description of female. Habitus ( Fig. 1 View FIGURE 1 A–C). Body slender, cylindrical with an inconspicuous boundary between prosome and urosome in dorsal view, without surface ornamentation other than sensilla. Holotype, total body length of 536 µm. Cephalothorax the widest part, and anal somite the narrowest, slightly tapering posteriorly.

Urosome ( Fig. 2 View FIGURE 2 A–B) contains five somites. In dorsal view, Uro5 furnished with a hyaline frill by having a semilunar extension middorsally. In ventral view, Uro4 and 5 ornamented with hyaline frills, and Uro5 is composed of closely set very fine setules inserted on the distalmost edge of the somite. Genital double-somite completely fused dorsally and ventrally. Genital apparatus oval-shaped, comprising of paired genital apertures located ventrally, and copulatory pore located ventro-medially. Anal somite ornamented with two curved rows of minute setules. Anal operculum is relatively proximal in position, slightly curved, ornamented with two curved rows of minute setules. Caudal rami much broader than long, furnished with one row of small spinules inserted on the distal edge of the anal somite. Each ramus carries seven caudal setae: seta I, the outermost aristate-tipped spiniform arising ventrally to the smallest seta II, seta III arising from the cylindrical extension at outer distal corner, seta IV and seta V well developed, seta V the longest not modified ( Fig. 1 View FIGURE 1 C), seta VI arising from a cylindrical extension at inner distal corner, seta VII slender slightly shorter than seta I located distally close to the inner margin of the ramus.

Rostrum ( Fig. 3 View FIGURE 3 A) relatively large, articulating with cephalothorax, bell-shaped with one pair of sensilla in the distal fifth.

Antennule ( Fig. 3 View FIGURE 3 A) moderately long, distinctly eight-segmented, the first four segments much broader than the distal four segments. Two aesthetascs, the larger one arising at the anterior margin of the fourth segment and the smaller one on the last segment. Armature formula: I (1), II (10), III (6), IV (4+aes), V (1), VI (2), VII (2), VIII (8+aes).

Antenna ( Fig. 3 View FIGURE 3 B) biramous with allobasis bearing exopod, and armed with one abexopodal pinnate seta. Exopod two-segmented; Exp1 with one pinnate seta; Exp2 with two pinnate setae and two setules. Endopod one-segmented, armed with four geniculate setae, one aristate-tipped, two pinnate spines, two tiny pinnate setae, ornamented with one row of small spinules parallel with some minute spinules on subdistal rim.

Mandible ( Fig. 3 View FIGURE 3 C). Coxal gnathobase well developed with sharp teeth, one small hollow tube on anterior surface, and ornamented with one unipinnate seta at inner distal corner. Basis furnished with one longitudinal row of minute spinules along outer margin, and one pinnate and two smooth setae at distal margin. Exopod one-segmented, with one smooth and two pinnate setae. Endopod one-segmented, with one pinnate, and five smooth setae (three longer, two shorter).

Maxillule ( Fig. 4 View FIGURE 4 A). Praecoxa ornamented with one short curved row of small spinules on surface and some at the origin of the basis. Praecoxal arthrite bearing two slender setae on anterior surface, nine sharp spines at anterior margin, and few minute spinules on the posterior edge. Coxa small with one terminal pinnate seta. Distal edge of basis with two pinnate and four smooth setae, ornamented with two short longitudinal rows of minute spinules at inner and outer margin. Exopod one-segmented with two pinnate setae. Endopod one-segmented, with one slender and two pinnate setae.

Maxilla ( Fig. 4 View FIGURE 4 B) with large syncoxa and three syncoxal endites. Anterior surface of syncoxa ornamented with four rows of small spinules (one of which contains spinules of 2 sizes) and a bundle of five long setules near the origin of the basis. Proximal endite with two, median endite with two, and distal endite with three pinnate spines. Basis with one smooth seta and armed claw. Endopod one-segmented with four smooth setae.

Maxilliped ( Fig. 4 View FIGURE 4 C). Syncoxa with one median and two pinnate distal setae, anterior surface furnished with two curved rows of larger and smaller spinules, and some minute spinules at the inner proximal margin.

Basis with one median and one subdistal smooth setae, anterior surface ornamented with one short row of small spinules near the inner margin. Endopod with one large smooth terminal claw and two slender setae.

P1 ( Fig. 3 View FIGURE 3 D). Praecoxa naked. Coxa furnished with several rows of larger and smaller spinules on anterior surface. Basis armed with one outer pinnate spine, some spinules at base of a straight inner pinnate spine that is displaced medially; spinules at base of inner spine and on the distal edge between the origins of the exopod and endopod, and with long spinules very close to the border with the coxa. Exopod three-segmented; Exp1 and Exp2 armed with one outer unipinnate spine each; Exp3 armed with one outer smooth and one terminal unipinnate spines, and two inner geniculate setae; Exp1 outer distal corner massively unguiform. Endopod three-segmented; Enp1 elongate, as long as the entire length of exopod, with one inner pectinate seta; Enp2 and Enp3 very short equal in length; Enp2 with one inner plumose seta; Enp3 with one outer unipinnate spine, one terminal geniculate and one inner smooth setae. Outer edge of exopod segments, Enp2 and Enp3 densely set with long stout spinules.

P2 ( Fig. 4 View FIGURE 4 D). Praecoxa naked. Coxa ornamented with several rows of spinules on anterior surface. Basis armed with one outer unipinnate spine; spinules on the distal edge between the origins of the exopod and endopod; inner distal corner unguiform and spinulose. Exopod three-segmented; Exp1 armed with one outer smooth spine; Exp2 armed with one outer pinnate spine and one inner spinulose seta; Exp3 armed with three outer spines (two smooth, one unipinnate), and two terminal spinulose setae. Endopod three-segmented; Enp1 with one short inner spinulose seta; Enp2 with one inner long spinulose seta; Enp3 with one outer pinnate spine, two terminal spinulose and one inner pectinate setae. Exp1, Exp2 and Enp2 with outer distal corner massively unguiform. Outer edge of all segments and distal edge of Exp1 densely set with long stout spinules.

P3 ( Fig. 4 View FIGURE 4 E). Praecoxa naked. Coxa ornamented with several rows of small spinules on anterior surface. Basis with one outer spinulose seta; spinules on the distal edge between the origins of the exopod and endopod; inner and outer distal corner unguiform and spinulose. Exopod three-segmented; Exp1 armed with 1 outer pinnate spine; Exp2 armed with one outer pinnate spine and one inner spinulose seta; Exp3 armed with three outer pinnate spines, two terminal and one inner spinulose setae. Endopod three-segmented; Enp1 and Enp2 with one inner spinulose seta each; Enp3 armed with one outer pinnate spine, two terminal spinulose setae, and two inner setae (one pectinate, one spinulose). Exp1, Exp2 and Enp2 with outer distal corner massively unguiform. Outer edge of all segments and distal edge of Exp1 densely set with long stout spinules.

P4 ( Fig. 4 View FIGURE 4 F). Praecoxa naked. Coxa ornamented with several rows of small spinules on anterior surface. Basis armed with one outer smooth seta; spinules on the distal edge between the origins of the exopod and endopod; inner distal corner rounded with one setule. Exopod much longer than endopod. Exopod threesegmented; Exp1 armed with one outer pinnate spine; Exp2 armed with one outer pinnate spine and one inner spinulose seta; Exp3 armed with three outer pinnate spines, two terminal spinulose setae, and two inner setae (one pectinate, one spinulose). Endopod three-segmented; Enp1 and Enp2 with one inner spinulose seta each; Enp3 armed with one outer pinnate spine, two terminal and one inner spinulose setae. Exp1, Exp2 and Enp2 with outer distal corner massively unguiform. Outer edge of all segments and distal edge of Exp1 densely set with long stout spinules. Armature formula of swimming legs in Table 1.

Basis Exopod Endopod

P1 I-I I −0; I −0; I,I,2 0−1; 0−1; I,1,1 P2 0-I I −0; I −1; III,2,0 0−1; 0−1; I,2,1 P3 0- 1 I −0; I −1; III,2,1 0−1; 0−1; I,2,2 P4 0- 1 I −0; I −1; III,2,2 0−1; 0−1; I,2,1 P5 ( Fig. 3 View FIGURE 3 E). Baseoendopod with one outer plumose basal seta, one outer and two inner pinnate endopodal spines, and two median long spinulose endopodal setae. Exopod oval-shaped, armed with one outer short pinnate spine, three median setae (two spinulose, one smooth in the middle), and one inner spinulose seta. Endopod distal edge spinulose between origins of setae 3 and 4.

P6 ( Fig. 2 View FIGURE 2 B) represented as a rectangular extension, bearing one outer small pinnate spine, and two terminal smooth setae of unequal length.

Description of male. Habitus ( Fig. 5 View FIGURE 5 A −C). Total body length 536 µm. General body shape and size similar to female. Sexual dimorphism expressed in antennule, Md, P1 basis and Enp1, P2 endopod, P5, P6, and urosomites.

Urosome ( Fig. 6 View FIGURE 6 A −B) contains six somites. In dorsal view, Uro4 to 6 ornamented with hyaline frills, and having a semilunar extension middorsally on Uro6. In vetral view, Uro4 and 5 furnished with small spinules at posterior margin, only Uro6 ornamented with a hyaline frill. Anal somite ornamented with one row of minute spinules ventrally. Anal operculum small, ornamented with two curved rows of fine setules. Caudal ramus much broader than long, with some spinules inserted on the posterior margin of anal somite. Armature and ornamentation similar to female.

Rostrum ( Fig. 7 View FIGURE 7 A) moderate in size similar to female.

Antennule ( Fig. 7 View FIGURE 7 A). Haplocerate, distinctly eight-segmented, the first four segments much broader than the last four segments. Aesthetascs as in female, on fourth and eight segments. All setae smooth, just two setae on fourth segment fork-tipped. Armature formula: I (1), II (12), III (5), IV (13+aes), V (1), VI (1), VII (3), VIII (7+aes).

Antenna ( Fig. 7 View FIGURE 7 B), Maxillule ( Fig. 6 View FIGURE 6 A), Maxilla ( Fig. 6 View FIGURE 6 B), and Maxilliped ( Fig. 6 View FIGURE 6 C) similar to corresponding structures of female.

Mandible ( Fig. 7 View FIGURE 7 C) as in female, except bearing two small hollow tubes on anterior surface at midlength of coxal gnathobase. Basis without ornamentation.

P1 ( Fig. 7 View FIGURE 7 D) similar to female, except for basis with one large inner ovate-striated knob; enp1 large with two small ovate-striated knobs on the anterior surface at proximal rim.

P2 ( Fig. 8 View FIGURE 8 D) exopod similar to female. Enp1 large with one pinnate seta; Enp2 transformed into one long, smooth spine-like attenuation, a medially directed knob close to Enp1, one spinulose and one pectinate setae of equal length, and one inner thick, club-like seta bifurcate at its tip, and longer than the outer spine.

P3 ( Fig. 8 View FIGURE 8 E) and P4 ( Fig. 8 View FIGURE 8 F) similar to female.

P5 ( Fig. 7 View FIGURE 7 E). Baseoendopod large bearing one outer long, smooth basal seta and two inner spinulose endopodal spines. Exopod oval-shaped, armed with two outer pinnate spines, two inner spinulose spines, and one median long smooth seta.

P6 ( Fig. 7 View FIGURE 7 E) located on ventral side of Uro3. Each leg armed with one outer and one median smooth setae, and one inner pinnate spinule.