Brevisomabathynella hahni, Cho & Humphreys, 2010
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publication ID |
https://doi.org/ 10.1080/00222930903537066 |
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persistent identifier |
https://treatment.plazi.org/id/03D887F9-FFCA-FFB0-FE6B-FC14B6156D77 |
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treatment provided by |
Carolina |
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scientific name |
Brevisomabathynella hahni |
| status |
sp. nov. |
Brevisomabathynella hahni sp. nov.
( Figures 34–37 View Figure 34 View Figure 35 View Figure 36 View Figure 37 )
Material examined
Holotype (adult female), allotype (adult male), paratypes (seven juveniles). Holotype: dissected on five slides ( WAM C 40294) . Allotype: dissected on five slides ( WAM C 40295) . Paratype: seven juveniles as a whole specimen on one slide ( WAM C 40296) .
Type locality
Australia, Western Australia, Pilbara, Millstream aquifer, piezometer 15B (21°44′35″ S, 117°14′30″ E), BES 3982, 18 October 1996, leg. W.F. Humphreys. GoogleMaps
Description of adult female (holotype)
Body. Length 1.35 mm. Head as long as anterior three thoracic segments 1–3 combined, approximately 10 times as long as wide ( Figure 34 View Figure 34 ).
Antennule ( Figure 35A View Figure 35 ). Seven-segmented. First segment with one seta on inner margin, with two simple dorsal setae and with one dorsal, one ventromedial and one lateral plumose seta. Second segment with one group of four plumose setae and with three simple setae on inner margin. Third segment with two lateral setae including one plumose seta and two setae on inner margin. Inner flagellum of third segment with three simple setae. Fourth segment with one stub seta and one plumose seta on dorsal margin, and with two stub setae and two plumose setae on outer distal apophysis. Fifth segment with two simple setae on inner margin, and with one aesthetasc and one simple seta dorsally. Sixth segment with two setae on inner margin and with two aesthetascs and one seta dorsally. Middle part of aesthetascs barely reaching seventh segment. Seventh segment with three subterminal aesthetascs and four simple setae.
Antenna ( Figure 35B View Figure 35 ). Five-segmented, as long as antennular segments 1–3 combined. Fourth segment slightly shorter than fifth segment. Setal formula: 0+0/ 0+0/1+0/1+1/4(1). Three simple setae on distal segment extremely short, at most as long as one-seventh of plumose seta.
Labrum ( Figure 35C View Figure 35 ). Flat, with eight teeth of more or less similar size flanked by two teeth decreasing in size laterally on each side. Ventral surface with two pair of teats and seven combs of ctenidia.
Mandible ( Figure 35D View Figure 35 ). Incisor process of four teeth. Tooth of ventral edge triangular. Spine row consisting of five spines. Palp of one segment, with one apical seta.
Maxillule ( Figure 35E View Figure 35 ). Two-segmented. Proximal segment with four setae on inner margin. Distal segment with two terminal spines, with three spines with denticles and with three simple setae of different size on outer margin.
Maxilla ( Figure 35F View Figure 35 ). Four-segmented, setal formula 3-3-8-7.
Thoracopods I–VII ( Figures 35M View Figure 35 , 36 View Figure 36 A–C, 37A–C). Thoracopods I–IV increasing in size posteriorly. Thoracopods IV–VI similar in size. Thoracopod VII as long as thoracopod I. Thoracopods I–VII each bearing one epipod on protopod. Basipod of thoracopods I–VII with one seta. Number of exopodal segments of thoracopods I– VII: 3-4-4-4-4-3-2. Endopod of thoracopods I–VII four-segmented, setal formulae:
Th. I 1+1/2+1/1+1/3(1)
Th. II–IV 1+1/1+1/0+1/3(1)
Th. V 0+1/1+1/0+1/3(1)
Th. VI, VII 0+0/1+1/0+1/3(1)
Thoracopod VIII ( Figure 35K View Figure 35 ). Conical, as long as endopod of male thoracopod VIII, with two terminal teeth.
First pleopod ( Figure 35L View Figure 35 ). First pleopod in form of two stubs separated from each other. Each stub bearing one terminal seta.
Uropod ( Figure 36D,E View Figure 36 ). Eight spines of similar size on inner margin of sympod. Exopod 35% as long as sympod, with four setae on outer and terminal margin, without basiventral setae. Endopod 42% as long as sympod, with one dorsal plumose seta near base, with two terminal setae and one subterminal plumose seta on outer margin, and with one terminal, one subterminal and one additional spine on inner margin. Terminal spine twice as long as subterminal spine. Inner-marginal spine spike-like, two-thirds as long as subterminal spine.
Pleotelson ( Figure 36D,E View Figure 36 ). One seta near base of each furcal ramus on both sides. Anal operculum concave.
Furcal rami ( Figure 36D,E View Figure 36 ). 1.3 times as long as wide, with two large terminal spines, and three smaller spines on inner margin, and with two dorsal setae.
Description of adult male (allotype)
Body. Length 1.31 mm. Identical to female except for following characters.
Thoracopod VIII ( Figure 35 View Figure 35 G–J). More or less oval in lateral view, twice as long as wide. Protopod massive, with prominent penial region. Epipod large, triangular, distal part barely reaching terminal end of penial region. Basipod without setae, inner margin of basipod drawn out into projection. Exopod one-third size of basipod, triangular, with four to five terminal denticles, but without setae. Endopod half as long as exopod, with two terminal setae.
Uropod. Sympod with seven spines. Exopod with three setae.
Etymology
The specific name refers to Dr H.J. Hahn (Landau, Germany) who provided material for our studies.
| WAM |
Western Australian Museum |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.