Philobrya wandelensis Lamy, 1906

Urcola, Matias Ricardo & Zelaya, Diego Gabriel, 2024, The Genus Philobrya J. G. Cooper, 1867 (Bivalvia: Philobryidae) In Patagonia And Adjacent Antarctic Waters, Zootaxa 5437 (2), pp. 151-192 : 184-185

Philobrya wandelensis Lamy, 1906

( Figure 18 )

Philobrya wandelensis Lamy, 1906a: 50 , 51, fig. 4; Melvill and Standen 1907: 116; Dell 1990: 29, figs. 42, 47–49; Absher and Feijó 1998: 440, fig. 3F; Narchi et al. 2002: 655, 656, figs. 14 and 43; Aldea & Troncoso 2008: 94, 95, 103, fig. 92; Jackson et al. 2015: fig. 2l; Urcola & Zelaya 2021: 25, 26, fig. 2.

Hochstetteria wandelensis . Carcelles 1953: 214, pl. 5, fig. 102.

Adacnarca wandelensis . Nicol 1966: 33, 34, pl. 3, figs. 4, 5; M̧hlenhardt-Siegel 1989: 160, pl. 2, fig. 16 and pl. 5, fig. 16; Hain 1990: 87, pl. 13, fig. 1a, b.

Remarks: Philobrya wandelensis was recently redescribed by Urcola & Zelaya (2021). The species is characterized by its modioliform shell with a long anterior portion of the dorsal margin, a microscopically pitted prodissoconch and a cancellate dissoconch covered with a dark brown periostracum, forming strong radial folds.

Philobrya wandelensis is most similar to P. sanjuani ( Fig. 16 ; see comparison under that species). Other morphologically similar species to P. wandelensis are P. atlantica ( Fig. 4 ), P. brattstromi ( Fig. 8 ), and the small-sized (up to 4.2 mm L) specimens of P. blakeana ( Fig. 6 ). Philobrya wandelensis clearly differs from all these species by having a pitted prodissoconch and shorter resilifer (Appendix 1). In addition, P. wandelensis differs from P. atlantica and P. brattstromi by having shorter periostracal setae and from P. blakeana by having a lower density of setae. Furthermore, P. wandelensis is distributed from Antarctica to the Scotia Arc islands, while P. atlantica , P. brattstromi , and P. blakeana appear around the southern tip of South America.

Figures

FIGURE 4. Philobrya atlantica. A: syntype (USNM 97057), B‒K: specimens from Santa Cruz Province (B‒F: MACN-In 44414, G‒K: MACN-In 44415). A‒E: outer views right valve (A‒D: with periostracum, E: without periostracum), F: outer view left valve (without periostracum), G: inner view left valve, H: inner view right valve, I: brooded embryo removed from the demibranch of an adult specimen, J, K: hinge plate of a 4.2 mm L specimen (J: left valve, K: right valve). Scale bars A‒H: 1 mm; I: 100 µm; J‒K: 500 µm.

FIGURE 6. Philobrya blakeana. A, I: lectotype of Brachidontes (Hormomya) blakeanus (MMUM EE 7674), B, J‒L, O, P: specimens from Tierra del Fuego (B: MACN-In 44420, J, K, O, P: MLP-Ma 16106, L: MLP-Ma 16108), C‒H, M, N: specimens from Burdwood Bank (MACN-In 44422). A‒C, E‒H: outer views right valve (A, B: with periostracum, C, E‒H: without periostracum), D: outer view left valve (without periostracum), I, J: inner views right valve, K: inner view left valve, L: brooded embryo removed from the demibranch of an adult specimen, M‒O: hinge plates right valve (M: specimen of 7.7 mm L, N: specimen of 5.2 mm L, O: specimen of 3.5 mm L), P: hinge plate left valve (specimen of 3.5 mm L). Scale bars A‒K: 1 mm; L: 100 µm; M‒P: 500 µm.

FIGURE 8. Philobrya brattstromi. A‒C, H, I, L‒N: specimens from Burdwood Bank (A, B, L: MACN-In 44438, C, H, I, M, N: MACN-In 44435), D, F, G, J, K: specimens from Tierra del Fuego (D: MACN-In 44432, F, G: MACN-In 44431, J, K: MLP-Ma 16114), E: holotype (NRM 3894). A‒D, F, J: outer views right valve (A: with periostracum, B‒D, F, J: without periostracum), E, G: outer views left valve (E: with periostracum, G: without periostracum), H: inner view left valve, I: inner view right valve, K: detail of prodissoconch, L, M: hinge plates left valve (L: specimen of 4.9 mm L, M: specimen of 3.3 mm L), N: hinge plate right valve (specimen of 3.2 mm L). Scale bars A‒I: 1 mm; J: 200 µm; K: 100 µm; L‒N: 500 µm.

FIGURE 16. Philobrya sanjuani. A‒C, J, K: paratypes (MACN-In 43524), D‒G: specimens from Shag Rocks (MLP-Ma 16135), H, I, L, M: holotype (MLP-Ma 15115). A, B, D‒G: outer views right valve (A: with periostracum, B, D‒G: without periostracum), C: outer view left valve (without periostracum), H: inner view left valve, I: inner view right valve, J: detail of prodissoconch, K, L: hinge plates right valve (K: specimen of 2.3 mm L, L: specimen of 2.7 mm L), M: hinge plate left valve (specimen of 2.7 mm L). Scale bars A‒I: 1 mm; J: 100 µm; K‒M: 500 µm. (Figures 16A‒C, H‒M are reproduced from Urcola & Zelaya (2021)).

FIGURE 18. Philobrya wandelensis. A, J: syntype (MNHN-IM-2000-31621), B, C, E‒I, K, L: specimens from South Georgia (MACN-In 43523), D: specimen from South Orkney (NMS Z 1921.143.701). A‒C, E: outer views right valve (A‒C: with periostracum, E: without periostracum), D, F: outer views left valve (D: with periostracum, F: without periostracum), G: inner view left valve, H: inner view right valve, I: detail of prodissoconch, J, K: hinge plates right valve (J: specimen of 4.1 mm L, K: specimen of 2.7 mm L), L: hinge plate left valve (specimen of 2.7 mm L). Scale bars A‒H: 1 mm; I: 100 µm; J‒L: 500 µm. (Figures 18A‒L are reproduced from Urcola & Zelaya (2021)).