Bythopussella aculeata ( Müller, 1908 ), Muller, 1908

Brandão, Simone N., 2008, New species of Bairdioidea (Crustacea, Ostracoda) from the Southern Ocean and discussions on Bairdoppilata simplex (Brady, 1880),? Bairdoppilata labiata (Müller, 1908) and Bythopussella aculeata (Müller, 1908) *, Zootaxa 1866, pp. 373-452 : 434-435

Bythopussella aculeata ( Müller, 1908)

( Figs. 43 , 45.P–S)

1908 Anchistrocheles aculeata Müller : 100–102, Pl. 14.7–14, Pl. 15.1–5. 1969 non Anchistrocheles ? sp. aff. A. aculeata, Maddocks : 113, Fig. 60m. 1990 Anchistrocheles aculeata, Warne : 114.

1997 Anchistrocheles ? aculeata, Hartmann: 55, Fig. 16.

Material. Since B. aculeata is the type species of the genus Bythopussella , I prefer not to designate a lectotype for B. aculeata , because the 5 adult specimens available are in very bad conditions (fragmented soft parts and valves). I think that the designation of a lectotype should be done when new material (in good condition) is available.

The syntype series of B. aculeata includes one glass containing specimens in alcohol and labelled “ Anchistrocheles aculeata Müller, Gauss­Station , 385m, Deut. Südpolar Exp., 1902­1903, ZMB 13086”:

1) This vial contained seven juveniles with completely decalcified valves – 6 (A­1), 1 (A­2). Additionally, four glass slides with dissected specimens and valves also form part of Müller’s syntype series:

2) Glass slide with permanent medium containing appendages, 1 RV and pieces of LV of 1 A F, and labelled “ Anchistrocheles aculeata, 1649 , Gauss., 177b female, 11.02”.

3) Glass slide with permanent medium containing very fragmented appendages, 1 RV and pieces of LV of 1 A M, and labelled “ Anchistrocheles aculeata, 1652 , Gauss., 177b male, 12.02”.

4) Glass slide with permanent medium containing very fragmented appendages, 1 RV and pieces of LV of 1 A M, and labelled “ Anchistrocheles aculeata, 1662 , Gauss., 177b male, 12.02”.

5) Glass slide with permanent medium containing fragmented appendages, 1 LV and pieces of RV of 1 juvenile?, plus one RLV positioned in dorsal view, and labelled “ Anchistrocheles aculeata, 1677 , Gauss., 177b, 1.03”.

Other specimens studied herein were in the vial of the types of Bairdoppilata labiata ( ZMB 13069):

6) 1 A M (dissected by myself, SNB 0687), and 1 (A­2) were previously together with the type series of Bairdoppilta labiata ( Müller, 1908) , in the vial labelled “ Nesidea labiata G. W. Müller, Gaus Station (177a), 385m, Deut. Südpolar Exp., 1901­1903, ZMB 13069, 177a ­ 12.02”. The adult male specimen is herein illustrated ( Fig. 45.P–S);

7) 1 (A­2) in vial labelled were previously together with the type series of Bairdoppilta labiata ( Müller, 1908) , in the vial labelled “ Nesidea labiata G. W. Müller, Gaus Station (177a), 385m, Deut. Südpolar Exp., 1901­1903, ZMB 13069, 177a – 1.03”.

Distribution. Only known from the type locality, Southern Ocean (Indic Sector), 385m.

Measurements. Syntypes: LV, A M (SNB 0657) L 0.94mm, H 0.54mm; (A­1) L 0.84mm, H 0.48mm; (A­ 2) L 0.63mm, H 0.40mm.

Diagnosis. Valves fairly large, bairdiid in aspect, with conspicuous lateral punctation in the central area of lateral surface (anterior and posterior are smooth); both valves with small spines on anterior margin; LV with 1 medium­sized spine on posterior margin. AII with elongate, slender podomeres; podomere VI with 1 long claw, and 1 medium­sized and 1 small setae in males and females. MxI with 7 strahlen. ApV robust.

Podomere V of ApV to VII with 1 long terminal claw, and one vestigial seta. Fu with 1 large and 1 mediumsized claws, and 2 medium­sized setae. Genital lobe subcircular with short, internal tube. Hemipenis with elongated/sub­hemispherical basal capsule, which presents a beaked­shaped distal part; short, fairly straight copulatory tube, and one rigid, chitinized, short, medial process.

Remarks. Details in chaetotaxy could not be studied in B. aculeata since all adults dissected and are preserved in a large quantity of permanent medium, which impedes their observation under the larger microscope objective magnification (100X).

Figures

FIGURE 43. Length: height scatter plot of the valves of Bythopussella aculeata (Müller, 1908), Bythopussella brandtae sp. nov. and Bythopussella sp. aff. B. brandtae sp. nov.