Clionolithes radicans Clarke, 1908

Fig. 5

Clionolithes radicans Clarke, 1908 (partim): 168, pl. 9, fig. 2, pl. 11, fig. 1 (fig. 1 = lectotype; pl. 10 and pl. 11, fig. 2 =? Calcideletrix flexuosa).

Pyritonema? gigas Fritsch, 1908: 10, pl. 4, figs 2–3.

Olkenbachia hirsuta Solle, 1938 (partim): 162, figs 2–4, 8, 11, 14 (figs 5–7, 10 = C. cervicornis, figs 9, 15, 17–18 = C. pannosa and fig. 13 = Nododendrina nodosa).

Clionolithes radicans – Clarke 1921 (partim): 88, figs 70, 72 (fig. 72 = lectotype, reproduced from Clarke 1908; fig. 71 =? Calcideletrix flexuosa). — Häntzschel 1962: W230, fig. 142-6 (= lectotype, reproduced from Clarke 1908); 1975: W125, fig. 71-1a–b (fig. 77-1a = lectotype, reproduced from Clarke 1908). — Plewes 1996: 175, pl. 26, figs 1–2, 4 (fig. 2 = lectotype). — Furlong & McRoberts 2014 (partim): 136, figs 5/1–4, 7 (fig. 5/1 = lectotype; fig 6/1–4 =?). — Buatois et al. 2017: 161, fig. 75C.

Clionolithes hackberryensis – Fenton & Fenton 1932 (partim): 44, pl. VI, figs 3–6 (figs 1–2 = Talpina hackberryensis comb. nov.).

Clionolithes? – (?) Tiedt 1958: 513, fig. 13, pl. 2, fig. 6.

Clionolithes sp. – (?) Easton 1962: 28, pl. 3, fig. 7.

Dendroid-Form II – (?) Schmidt 1992: 89, pl. 11, figs 3–4. — (?) Glaub & Schmidt 1994: 106, pl. 3, fig. 1.

Dendroid-Form B – (?) Bundschuh 2000: 65, pl. 9, figs 1–2.

Nododendrina nodosa – Klug et al. 2008: 159, pl. 2, fig. 2, pl. 17, fig. 14.

Rosette-shaped borings – (?) Botquelen & Mayoral 2005: 1061, fig. 2i.

non Clionolithes radicans – Fenton & Fenton 1932: 43, pl. 6, fig. 7 (? Calcideletrix flexuosa; reproduced from Clarke 1908). — Blissett & Pickerill 2004: 171, fig. 3/3.

Original diagnosis

n/a

Emended diagnosis

Numerous galleries radiate and branch outward from a small and often elongated central node. Branching dichotomous or irregular, and galleries taper to fine, pointed ends. Branches cross one another rather than coalesce at the edge of the trace. Outline irregular but roughly oval.

Original description

[…] tubes radiate and branch outward from a center, giving a decided rootlike expression to the resultant very complicated combination of tubes. These branching tubes often unite, fuse or anastomose producing a somewhat irregularly articulated expression. This sponge particularly infested the living and dead shells of the brachiopods, finding entrances less often at the margin than through the pores on the surface of the shell.

Supplementary description

In the detailed description of the junior synonym Olkenbachia hirsuta, Solle (1938) added the observations that the overall shape of the trace is often roughly oval, branching is dichotomous or irregular, and galleries taper to fine, pointed ends. Furthermore, he pointed out a considerable morphological variability due to varying environmental conditions and different substrate species. The trace is usually less than 4 mm in diameter but branches may reach up to 3.5 mm in length (Solle 1938 for junior synonym O. hirsuta).

Type material, locality and horizon

Clarke (1908) depicts four brachiopod specimens with numerous C. radicans and one drawing (syntypes). None of these specimens was designated as holotype. Clarke (1921) reproduced all but one of his original illustrations but again did not explicitly address a holotype. Solle (1938) attempted to designate a “Typus” but when doing so referred to two different specimens (Clarke 1908: pl. 11, fig. 2 and 1921: fig. 87). Häntzschel (1962) selected another one of the specimens, a natural cast in an atryparetic shell illustrated with a drawing (Clarke 1908: pl. 11, fig. 1), but this selection alone cannot be considered a valid lectotype designation. Plewes (1996) revisited and illustrated the same specimen, explicitly addressing it as the holotype, but no reasoning for this designation was given, and this was not formally published. Furlong & McRoberts (2014) were the next to partly revise C. radicans, including another illustration of the same specimen selected by Häntzschel (1962) and by Plewes (1996), but refraining from stating any type attribute. In conclusion, none of the above publications constitute a valid lectotype designation (ICZN article 74), which is herein formally established by selecting the specimen depicted by Clarke (1908: pl. 11, fig. 1) as lectotype (Fig. 5 A–C), rendering all other specimens depicted in Clarke 1908 (pl. 9, figs 1–2, pl. 10, pl. 11, fig. 2) as paralectotypes. This selection is in accordance with Häntzschel (1962) and Plewes (1996) and the chosen specimen perfectly matches the wording of Clarke’s original description. It is preserved as a natural cast, together with five further specimens, in an Atrypa reticularis brachiopod shell from the Upper Devonian Chemung Beds of Mansfield, Pennsylvania, USA, and is housed in the New York State Museum (NYSM 6702).

Remarks

Solle (1938) studied well-preserved natural casts in brachiopod and bivalve shells from the Devonian near Koblenz, Germany, and established several ichnospecies within the new ichnogenus Olkenbachia. Teichert (1945) stated that Olkenbachia is reminiscent of Clarke’s Clionolithes and thus to be regarded as a junior synonym. The holotype of O. hirsuta (Fig. 5D) is currently lost, but its original illustration and a reinvestigation of several paratypes confirm the synonymy of the Olkenbachia type ichnospecies O. hirsuta with C. radicans (Fig. 5 E–F). Olkenbachia simplex is considered to be a poorly preserved C. radicans and not a separate ichnospecies. In contrast, a reinvestigation of the holotype of O. pannosa identified this ichnospecies as being separate (see below).