Kimberleybathynella mandorana, Cho & Park & Humphreys, 2005

Cho, Joo-Lae, Park, Jong-Geun & Humphreys, W. F., 2005, A new genus and six new species of the Parabathynellidae (Bathynellacea, Syncarida) from the Kimberley region, Western Australia, Journal of Natural History 39 (24), pp. 2225-2255 : 2240-2243

Kimberleybathynella mandorana n. sp.

( Figures 11–13 )

Type material

Holotype: „ dissected on five slides, Mandora , Western Australia, Australia, Friday Well bore (19 ° 429270S, 121 ° 279420E), BES 7559, 19 October 1999, A. Storey leg. coll. Western Australian Museum, Perth ( WAM C 34252) . Allotype: ♀ dissected on five slides, same data as for holotype ( WAM 34253) . Paratypes: 2♀♀ each on a slide, same data as for holotype ( WAM C 34254 and 34255) .

Etymology

The species is named after Mandora, where the species was collected.

Description of adults

Size (mm). Body length: „ 1.38, ♀ 1.33–1.41, approximately 14 times as long as wide ( Figure 11 ). Head as long as length of segments 1–3. The female differs from the male only in thoracopod VIII.

Antennule ( Figure 12A ). Antennule six-segmented. First segment with one seta on inner distal margin, with one simple dorsal seta, and with one dorsolateral, one lateral and one ventromedial plumose setae. Second segment with one group of four plumose setae and one simple seta on inner distal margin. Third segment with two setae on outer margin, one simple seta on inner distal margin and one ventral seta. Peduncle of third segment with three simple setae. Fourth segment with one stub seta on dorsal margin, and with three plumose setae. Fifth segment with two setae on inner margin, with two aesthetascs and one simple seta dorsally, and with one lateral aesthetasc. Sixth segment with four terminal setae and three subterminal aesthetascs.

Antenna ( Figure 12B ). Antenna two-segmented, setation as in K. gigantea . Labrum ( Figure 12C ). Labrum flat, with two median teeth flanked by four main and three additional teeth on both lateral sides. All teeth terminally denticulated.

Mandible ( Figure 12D, E ). Mandible as in K. gigantea except the incisor process of three teeth.

Maxillule ( Figure 12F ). Maxillule two-segmented, ornamentation as in K. gigantea except that the three simple setae on outer distal margin of the distal segment exceed the base of the terminal claws.

Maxilla ( Figure 12G ). Maxilla four-segmented. Second segment half fused with third segment; setal formula 2-4-14-1.

Thoracopods I–VII ( Figures 12H–K , 13A–C ). Thoracopods I–VII as in K. gigantea except the following. Exopodite of thoracopods I–VII with two terminal setae and with one seta on inner margin. Setal formulae of endopodite of thoracopods I–VII: thoracopods I: 0+0/1+1/ 1+0/2; thoracopods II–VI: 0+0/0+1/0+1/2; thoracopods VII: 0+0/0+1/0+1/1.

Thoracopod VIII. Thoracopod VIII of male ( Figure 12L, M ) half-spherical in lateral view. Protopodite massive. Penial region protruded. Epipodite absent. Basipodite without setae, inner margin of basipodite drawn out into projection. Exopodite triangular, bearing three setae. Endopodite as large as exopodite, denticulated terminally. Thoracopod VIII of female ( Figure 12N ) in form of a bifurcated structure resulting from the basal fusion of left and right thoracopods. Distal end of each branch sharp.

First pleomere. First pleomere with a pair of setae.

Uropod ( Figure 13D, E ). Uropod bearing seven spines on inner distal margin of sympodite. Distal spine 1.5 times as long as and twice as thick as proximal spines of equal size. Endopodite 30% as long as sympodite, drawn out distally into slightly curved spur, with two setae at base of spur. Exopodite as long as endopodite, with two terminal setae and one ventromedian seta. Outer one of both terminal setae twice as long as somewhat thicker inner seta.

Pleotelson ( Figure 13E, F ). Pleotelson with one seta at base of furcal rami on both sides. Anal operculum flat, protruded slightly.

Furcal rami ( Figure 13E, F ). Furcal rami 1.2 times as long as wide, with five spines and with two dorsal plumose setae.

Figures

Figure 11. Kimberleybathynella mandorana gen. et sp. nov. General habitus „, lateral. Scale bar: 0.5 mm.

Figure 12. Kimberleybathynella mandorana gen. et sp. nov. (A) Right A. I „ (dorsal); (B) right A. II „ (dorsal); (C) Labr. „ (ventral); (D) right Md. „ (ventral); (E) incisor process of left mandible; (F) left Mx. I „ (dorsal); (G) right Mx. II „ (dorsal); (H) left Th. I „ (frontal); (I) right Th. II „ (frontal); (J) left Th. III „ (frontal); (K) left Th. IV „ (frontal); (L) right Th. VIII „ (lateral); (M) Th. VIII „ (ventral); (N) Th. VIII ♀ (ventral). Scale bars: 0.1 mm (A–K); 0.05 mm (L–N).

Figure 13. Kimberleybathynella mandorana gen. et sp. nov. (A) Left Th. V „ (frontal); (B) right Th. VI „ (frontal); (C) left Th. VII „ (frontal); (D) Right uropod „ (dorsal); (E) pleotelson, furca and uropod „ (lateral); (F) pleotelson and furca „ (dorsal). Scale bars: 0.1 mm.