Namanereis pilbarensis, Glasby & Fiege & Damme, 2014

Glasby, Christopher J., Fiege, Dieter & Damme, Kay Van, 2014, Stygobiont polychaetes: notes on the morphology and the origins of groundwater Namanereis (Annelida: Nereididae: Namanereidinae), with a description of two new species, Zoological Journal of the Linnean Society 171 (1), pp. 22-37 : 24-26

publication ID

https://doi.org/ 10.1111/zoj.12130

persistent identifier

https://treatment.plazi.org/id/039D87CE-1972-FFAE-24D3-FA06D1C2731D

treatment provided by

Marcus

scientific name

Namanereis pilbarensis
status

SP. NOV.

NAMANEREIS PILBARENSIS SP. NOV.

( FIGS 1A–C View Figure 1 , 2A–G View Figure 2 , 3A–G View Figure 3 )

Specimens examined

Holotype: Australia, Pilbara region , Site PSS330 View Materials , Duffers , Ashburton River catchment, 23°47.27′S, 117°48.41′E, 298 m asl, approx 25 km north of Pingandy Road on the Ashburton Downs – Meekatharra Road, coll. M. Scanlon & J. Cocking, 21.vii.2004 ( WAM V8206 ) GoogleMaps . Paratypes: Australia, Pilbara region , Site PSS016 View Materials , Robe , Onslow Coast Basin, 21°34.88′S, 115°52.23′E, 54 m asl, bore on Yarraloola Station, coll. M. Scanlon & J. Cocking, 14.xi.2002, two specimens ( NTM W19176 View Materials ), one specimen ( NTM W25486 View Materials ), one specimen ( NTM rated with single terminal and seven subterminal teeth. Notochaetae absent. Neurochaetae in type C arrangement as defined by Glasby (1999). Supraneuroacicular falcigers of chaetiger 10 with blades about 4.9 times longer than width of shaft head, blades finely serrat- ed, seven to 11 teeth. Subacicular neurochaetae include heterogomph falcigers, heterogomph spinigers, and heterogomph pseudospinigers. GoogleMaps

W25487 View Materials ); Site PSS309 View Materials , Wickham Well , De Grey River catchment, 22°2.27′S, 120°35.24′E, 410 m asl, approx. 50 km north-west of Noreena Downs Homestead, coll. M. Scanlon & J. Cocking, 15.vii.2004, four specimens, few plus headless fragments ( SMF 22369 View Materials , 2 View Materials cs and fragments; SMF 22370 View Materials : SEM stub 1203, 1 cs; SMF 22371 View Materials : SEM stub 1204, 1 cs); Site FMG13, Dandy Well , De Grey River catchment, 22°11.55′S, 119°53.22′E, 491 m asl, Bonney Downs Station, well located to creekline, coll. M. Scanlon & J. Cocking, 12.iii.2005, one specimen ( SMF 22372 View Materials : SEM stub1202, 1 cs–p) GoogleMaps .

Type locality

Duffers, Ashburton River catchment, Pilbara, Australia.

Etymology

Species name based on region of occurrence.

Diagnosis

Prostomium not cleft anteriorly. Antennae cirriform. Eyes absent. Three pairs of tentacular cirri. Jaws ser- Description

Body elongate, uniform width along most of body, slightly tapering over far posterior body ( Fig. 1A, C View Figure 1 ). Dorsal side convex, ventral side flattened. Colour in alcohol specimens yellow-white, epidermal pigment absent; in life semitransparent ( Fig. 1A View Figure 1 ). Holotype cs, 10.5 mm long, 0.9 mm wide at chaetiger 10 including parapodia and chaetae, 78 chaetigers. Paratypes range from 4.4– 4.6 mm long, 0.45–0.50 mm wide, 30–36 chaetigers (N = 3).

Prostomium subtriangular, slightly wider than long with widest part near posterior end; anterior end entire without cleft, shallow dorsal depression present ( Fig. 1B View Figure 1 ). One pair of antennae inserted over inner-mid palps; cirriform, extending to level with or just beyond tip of palps. Palps massive, biarticulate. Eyes absent ( Fig. 2A, B View Figure 2 ).

Peristomium with three pairs of tentacular cirri with indistinct cirrophores; smooth to slightly wrinkled cirrostyles. Anterodorsal and posterodorsal cirri of about same length, anteroventral slightly shorter. Posterodorsal cirri extending to chaetiger 2 ( Fig. 2A View Figure 2 ). Pharynx retracted in holotype, everted in some paratypes. Jaws of paratypes serrated with single terminal tooth and about seven subterminal teeth; proximal-most ones ensheathed ( Figs 2C View Figure 2 , 3G View Figure 3 ).

Parapodia with conical acicular neuropodial ligule. Dorsal cirri cirriform, increasing in length posteriorly, half length of acicular neuropodial ligule anteriorly, about equal length of acicular neuropodial ligule posteriorly. Ventral cirri anteriorly subulate about twothirds length of neuropodial ligule, posteriorly cirriform and about half length of neuropodial ligule ( Figs 2A, D View Figure 2 , 3A, B View Figure 3 ).

Notochaetae absent. Neurochaetae in type C arrangement, i.e. supraneuroacicular chaetae consist of one sesquigomph spiniger in postacicular fascicle and one heterogomph falciger in preacicular fascicle. Subneuroacicular fascicle in postacicular position comprising two heterogomph falcigers and one to two distally bifid heterogomph pseudospinigers (rarely heterogomph spinigers) ( Figs 2D, F View Figure 2 , 3C–F View Figure 3 ).

Supraneuroacicular sesquigomph spinigers with boss about 1.8 times length of collar. Supraneuroacicular falcigers of chaetiger 10 with blades about 4.9 times longer than width of shaft head, finely serrated, eight teeth ( Fig. 2E View Figure 2 ). Subneuroacicular falcigers of chaetiger 10 with very finely serrated blades, nine to ten teeth, about 5.1 times longer than width of shaft.

Pygidium tripartite, with small subpointed dorsal lobe and two larger ventral lobes bearing pair of smooth, cirriform anal cirri, equal in length to two to three times the width of pygidium. Anus terminal ( Fig. 2G View Figure 2 ).

Remarks

Namanereis pilbarensis sp. nov. was first discovered by Scanlon et al. (2006), identified tentatively as an ‘undescribed marine polychaete’. It can be distinguished from all other members of the genus by having distally bifid heterogomph pseudospinigers. It may be distinguished from other groundwater Namanereis species by the combination of jaws with a single terminal tooth and series of subterminal teeth (the typical nereidid condition) and relatively few (seven to 11) serrations on the supraneuroacicular falcigers ( Table 1). Habitat

Bore holes in cattle pastoral areas intermittently flowing river catchments in the Pilbara, 54–491 m asl, salinity 0.5–1.5 ppt, temperature 28–31 °C.

Distribution

Pilbara, north-west Australia.

WAM

Western Australian Museum

NTM

Northern Territory Museum of Arts and Sciences

SMF

Forschungsinstitut und Natur-Museum Senckenberg

Kingdom

Animalia

Phylum

Annelida

Class

Polychaeta

Order

Phyllodocida

Family

Nereididae

Genus

Namanereis