Stichomitra, Cayeux, 1897

Kochhann, Karlos G. D., Baecker-Fauth, Simone & Fauth, Gerson, 2013, Late Maastrichtian Radiolaria from ODP Leg 165 - Site 999 B, Colombian Basin, Geodiversitas 35 (1), pp. 5-20 : 12

Stichomitra ? sp. 1

( Fig. 4J )

FIGURED SPECIMEN. — ULVG-7327.

MATERIAL. — Four specimens (recovered with the hydrogen peroxide method); two specimens (recovered with the acetic acid method).

DESCRIPTION

Multi-segmented Nassellaria (with probably six segments),spindle-shaped in outline.The poreless cephalis bears a small and curved apical horn. Post-cephalic segments increase regularly in width and height until a median segment; strictures between segments welldeveloped.Thorax,abdomen and post-abdominal segments possess circular pores, apparently, quincuncially arranged. Distal segments inverted conical in shape.

REMARKS

Besides its similarity to Stichomitra carnegiense (Campbell & Clark, 1944) , the poor preservation of the recovered specimens does not enable the identification of the key characteristics in the apical horn, and in the upper segments. In disagreement to the description of S. carnegiense , the described species also bears spindle-shaped outline.

Figures

FIG. 4. — SEM images of Radiolaria recovered from the sample 999B/60/2W/70-74 cm: A, Archaeodictyomitra cf. A. squinaboli Pes- sagno,1976 (H2O2 method);B, Archaeodictyomitra cf. A. lamellicostata (Foreman, 1968) (H2O2 method); C, Archaeodictyomitra? sp. 1 (H2O2 method); D, Archaeodictyomitra? sp. 2 (H2O2 method); E, Dictyomitra sp. 1 (H2O2 method); F, Dictyomitra sp. 2 (H2O2 method); G, Mita regina? (Campbell & Clark, 1944) (CH3COOH method); H, Amphipyndax tylotus Foreman, 1978 (H2O2 method); I, Stichomitra asymbatos Foreman,1968 (H2O2 method);J, Stichomitra? sp.1 (H2O2 method); K, Stichomitra? sp. 2 (H2O2 method); L, Rhopalosyrin- gium magnificum Campbell & Clark,1944 (H2O2 method). The chemical compound after each species indicates the chemical method applied in the recovery of each figured specimen. Scale bars: 100 µm.