Allobathynella yecheonensis, 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 : 116-122

publication ID	https://doi.org/ 10.12651/JSR.2016.5.1.049
persistent identifier	https://treatment.plazi.org/id/039B482E-FF9D-1E55-FF3B-FD8CFEE1FCA7
treatment provided by	Felipe
scientific name	Allobathynella yecheonensis
status	sp. nov.

Treatment

Allobathynella yecheonensis sp. nov. ( Figs. 58-62 View Fig )

Etymology

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

Material examined

Holotype (adult female), allotype (adult male), paratype (two adult females and one adult male). Holotype dissected on eight slides ( NIBR IV0000267084 ) . Allotype dissected on eight slides ( NIBR IV0000267085 ). One female paratype dissected on seven slides ( NIBR IV0000267086 ), one male and one female paratypes ( NIBR IV0000267087 , 0000267088 View Materials ) each as a whole specimen in separate slides .

Type locality

South-Korea, Gyeongsangbuk-Do, Yecheon-Gun, Yonggung-Myeon (36°35′10.2″N, 120°19′27.5″E), 07. October 2012, leg. J.-L. Cho. GoogleMaps

Description

Size (mm). Body length: Ş 2.40 (other females: 2.20- 2.38; ♂: 2.18-2.37), approximately 10 times as long as wide. Head as long as anterior three thoracic segments combined ( Fig. 58A View Fig ). Male differs from female in protopod of thoracopod VI and thoracopod VIII.

Antennule ( Fig. 58B 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 each two simple setae dorsally and ventrally on inner distal margin. Third segment with two lateral setae including one plumose seta, with two ventrolateral setae, and two dorsal setae 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. 58C View Fig ) 7-segmented, as long as the length of antennular segments 1-5. Setal formula: 0 + 0/0 + 0/1 + 0/1 + 1/0 + 0/1 + 1 + 1/5(1).

Labrum ( Fig. 58D View Fig ) flat, with eight main teeth flanked by three (left) or five (right) teeth on both lateral sides. Ventral surface convex, with shield-shaped chitin plate, with one round median projection bearing two spinules and one pair of teats and with numerous combs of ctenidia on convex surface.

Mandible ( Fig. 59A) with incisor process of four teeth. Tooth of ventral edge absent. Spine row consisting of eight spines. Palp of one segment, 2.5 times as long as wide, with one long terminal seta and one short subterminal seta. Terminal seta 2.5 times longer than subterminal seta.

Maxillule ( Fig. 59B) two-segmented. Proximal segment with four setae on inner distal margin. Distal segment with two terminal smooth spines, with four smooth spines on inner edge, and with three simple setae on outer distal margin. Terminal spine two times as long as other ones.

Maxilla ( Fig. 59C) four-segmented, setal formula 3-4- 10-6.

Thoracopods I-VII ( Figs. 59 D-F, 60A-C, 61A). Thoracopod I-IV increasing in size posteriorly. Thoracopods IV-VII similar in size. Thoracopods IV-VII each bearing one epipod on protopod. Basipod with two distal setae in thoracopod I, with one distal seta in thoracopods II and III, with each one distal and median seta in thoracopods IV-VII. Number of segments of exopod of thoracopods I-VII: 3-4-4-5-5-5-4. Exopodal segments with each one dorsal and ventral seta, except basal segment lacking dorsal seta in thoracopods I, II, IV, V, VI, VII. Tiny process present between two setae of distal segment. 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)

Thoracopod II 1 + 1/2 + 2/1 + 1/4(2)

Thoracopods III, IV, V 1 + 1/2 + 2/0 + 1/4(2)

Thoracopods VI, VII 0 + 1/1 + 2/0 + 1/3(1)

Thoracopod VIII of male ( Fig. 61E, F View Fig ) perpendicular to body, in form of a bell in lateral view, 1.3 times longer than wide. Protopod with a prominent penial region bearing a distal opening. Inner margin of penial region (dental lobe) with nine teeth. Epipod flat, with round distal part barely reaching lower margin of exopod. Basipod with one small seta near base of endopod, inner margin dentate, distally drawn out into round projection bearing three spinules. Basipodal seta one half as long as endopod. Exopod one third of size of basipod, round,

118 JOURNAL OF SPECIES RESEARCH Vol. 5, No. 1

A D D-F C B A-C E F

with two distal lobes bearing three spinules each respectively. Endopod small, round, with two distal setae of different size. Outer seta three times longer than inner one. Thoracopod VIII of female ( Fig. 61C View Fig ) conical in ventral view, with two spine-like distal projections.

First pleopod ( Fig. 61D View Fig ) in form of stub bearing two distal setae.

Uropod ( Fig. 62A, C View Fig ) bearing eight spines on inner margin of sympod, two most distal spine significantly larger than other ones of similar size. Endopod 52% as long as sympod, dorsally with two 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 three additional spines on inner margin. Terminal spine longer than subterminal one. Most distal spine of inner margin smaller than subterminal one, 50% as large as terminal one. Two proximal spines of inner margin small, one fourth as large as distal one. Exopod shorter than endopod (47% of sympod), with six setae inclusive of one basi-ventral seta.

Pleotelson ( Fig. 62B, C View Fig ) without seta. Anal operculum protruded with round tip.

Furcal rami ( Fig. 62B, C View Fig ) 1.2 times as long as wide, with two large distal spines and three successively smaller spines on inner margin, and dorsally with two plumose setae.