Allobathynella okcheonensis, Park & Cho, 2016

Park, Jong-Geun & Cho, Joo-Lae, 2016, Fourteen new species of Allobathynella Morimoto and Miura, 1957 from South Korea: with a redescription of A. coreana Morimoto, 1970 (Crustacea, Bathynellacea, Parabathynellidae), Journal of Species Research 5 (1), pp. 49-156 : 90-96

publication ID	https://doi.org/ 10.12651/JSR.2016.5.1.049
persistent identifier	https://treatment.plazi.org/id/039B482E-FFF7-1E33-FF3B-FCCDFD71FC67
treatment provided by	Felipe
scientific name	Allobathynella okcheonensis
status	sp. nov.

Treatment

Allobathynella okcheonensis sp. nov. ( Figs. 36-40 View Fig View Fig View Fig View Fig View Fig )

Etymology

The species name is derived from the county (Okcheon-Gun), where the material was collected.

Material examined

Holotype (adult female), allotype (adult male), paratype (adult male). Holotype dissected on seven slides ( NIBR IV0000140013 ) . Allotype dissected on four slides ( NIBR IV0000140014 ) .

Paratype kept as a whole specimen in a slide ( NIBR IV0000140015 ) .

Type locality

South-Korea, Chungcheogbuk-Do, Okcheon-Gun Iweon-Myeon (36°14′36.5″N, 127°37′18.5″E), 04. April 2010, leg. J.-L. Cho and J.-G. Park.

Description

Size (mm). Body length: Ş 2.73, ♂ 2.47, 2.26, approximately 14 times as long as wide. Head slightly shorter than anterior three thoracic segments combined ( Fig. 36A View Fig ). Female differs from male in protopod of thoracopod VI and thoracopod VIII .

Antennule ( Fig. 36B View Fig ) 7-segmented. First segment with one seta on inner distal margin, with two simple dorsal setae and with four plumose setae. Position of each plumose setae: dorsally, dorso-laterally, laterally and ventro-laterally. Second segment with one group of four plumose setae and with two simple setae dorsally and one simple seta ventrally on inner distal margin. Third segment with two lateral setae including one plumose seta, with two ventrolateral setae, and one dorsal seta and two ventral setae on inner distal margin. Inner flagellum of third segment with three simple setae. Fourth segment with one stub setae and one plumose seta on dorsal margin, and with two stub setae and two plumose setae on outer distal apophysis. Fifth segment distally with two simple setae and one small plumose seta, two dorsal aesthetascs and one simple seta. Sixth segment with four setae including one plumose seta on inner margin, and with two aesthetascs and one simple seta and one aesthetasc dorsally. Seventh segment with three subterminal aesthetascs and four simple setae.

Antenna ( Fig. 36C View Fig ) 7-segmented, as long as length of antennular segments 1-5. Setal formula: 0+ 0/0 + 0/1 + 0/1 + 1/0 + 0/1 + 2/5(1).

Labrum ( Fig. 37A View Fig ) flat, with eight main teeth flanked by two teeth on both lateral sides. Ventral surface concave, with two round median projections without spinules, numerous combs of ctenidia and two pairs of teats.

Mandible ( Fig. 37B, C View Fig ) with incisor process of four teeth. Tooth of ventral edge absent. Spine row consisting of 15 spines. Palp of one segment, 2.5 times as long as wide, with one long terminal seta and one subterminal seta. Subterminal seta as long as one third of terminal one.

Maxillule ( Fig. 37D View Fig ) two-segmented. Proximal segment with numerous numbers of ctenidia and with four setae on inner distal margin. Distal segment with two terminal smooth spines and five dentate spines on inner edge, and with three simple setae on outer distal margin. Terminal spine 1.5 times as long as other ones.

Maxilla ( Fig. 37F View Fig ) four-segmented, setal formula 3-5- 11-8.

Thoracopods I-VII ( Figs. 37F, G View Fig , 38 View Fig A-C, 39A-C). Thoracopod I-IV increasing in size posteriorly. Thoracopods IV-VII similar in size. Thoracopods III-VII each bearing one epipod on protopod. Basipod with two distal setae in thoracopod I, with one distal seta in thoracopods II-VI, and with each one distal and median seta in thoracopod VII. Number of segments of exopod of thoracopods I-VII: 3-4-5-6-6-6-6. Exopodal segments with each one dorsal and ventral seta, except basal segment lacking dorsal seta in thoracopods III-VII. Tiny process present between two setae of distal segment. Dorsal seta on distal segment of exopod barbed with strong hairs. Endopod of thoracopods I-VII four-segmented, setal formulae:

Thoracopod I 2 + 1/3 + 2/1 + 1/4(2)

Thoracopods II, III 1 + 1/2 + 2/1 + 1/4(2)

Thoracopods IV-VI 1 + 1/2 + 2/0 + 1/4(2)

Thoracopod VII 1 + 1/1 + 2/0 + 0/4(2)

Thoracopod VIII of male ( Fig. 40A, B View Fig ) perpendicular to body, in form of a bell in lateral view, 1.5 times longer than wide. Protopod with a prominent penial region bearing a distal opening. Inner margin of penial region with numerous tiny teeth. Epipod flat, with round distal part not reaching lower margin of exopod. Basipod with one short seta near base of endopod, distally drawn out into round projection, basipodal seta two thirds as long as endopod. Exopod one third of size of basipod, round, with two distal lobes. Each lobes with three dentils, respectively. Endopod small, round, with two distal setae of different size. Outer seta two times longer than inner one. Thoracopod VIII of female ( Fig. 40C View Fig ) of female tiny, round in ventral view, with a projection forked distally.

First pleopod ( Fig. 40D View Fig ) in form of stub bearing two distal setae.

Uropod ( Fig. 40E, F View Fig ) bearing ten spines on inner margin of sympod. Two distal spines longer and thicker than others. Endopod 53% as long as sympod, with two dorsal plumose setae near base, with two terminal setae and one subterminal plumose seta on outer margin and with one terminal spine, one subterminal spine and four(right) or five (left) additional spines on inner margin. Terminal spine slightly thicker and stronger than subterminal one. Most distal spine of inner margin 50% as large as terminal spine and 1.5 times as large as proximal spine. Exopod slightly shorter than endopod (50% of sympod), with seven setae inclusive of one basi-ventral seta.

Pleotelson ( Fig. 40E View Fig ) without seta. Anal operculum protruded with round tip.

Furcal rami ( Fig. 40E View Fig , G-I) 1.2 times as long as wide, with two large distal spines, and six smaller spines on inner margin, and with two dorsal plumose setae.