Nanaphora leei Fernandes & Pimenta, 2015

Fernandes, Maurício Romulo, 2024, Triphoridae (Gastropoda) from Martinique sampled by the MADIBENTHOS expedition, with notes on shallow-water species from Guadeloupe, Zoosystema 46 (18), pp. 457-503 : 480-483

Nanaphora leei Fernandes & Pimenta, 2015

( Figs 14 ; 15 ; 19 G-H)

Nanaphora leei Fernandes & Pimenta, 2015: 503 , fig. 5.

Cheirodonta verbernei non Moolenbeek & Faber, 1989 – Zhang 2011: 99, fig. 288. — Lamy & Pointier 2018: 284, pl. 91, fig. 3.

Nanaphora verbernei non Moolenbeek & Faber, 1989 – Fernandes & Pimenta 2015: 500 , fig. 4. — Fernandes & Pimenta 2019b: 30 , figs 2G, 19-20. — Fernandes & Pimenta 2020: 152 , figs 23R, 84A. — Rolán & Fernández-Garcés 2015: 53, fig. 4W. — Bandeira 2019: 24, 56. — Cesar 2020: 40, fig. 8D.

Nanaphora leei – Fernandes & Pimenta 2020: 55, fig. 23Q.

TYPE MATERIAL. — Holotype. Brazil • sh; Espírito Santo state, Guarapari, Praia de Meaípe ; depth 20-25 m; MNRJ 34086 .

Paratypes. Brazil • 2 sh; Rio de Janeiro state, Campos Basin ; 22°42’ S, 40°40’ W; 2007; MNRJ 29765 .

TYPE LOCALITY. — Brazil: Espírito Santo state, Guarapari, Praia de Meaípe; 20- 25 m.

MATERIAL EXAMINED. — Guadeloupe. KARUBENTHOS 1 • 1 sh; sta. GS14; MNHN • 1 sh; sta. GS34; MNHN.

Martinique. MADIBENTHOS. ‘Nord Atlantique’ • 1 sh; sta. AB197; MNHN • 2 sh; sta. AB260; MNHN • 1 sh; sta. AS557; MNHN. — ‘Sud Atlantique’ • 1 sh; sta. AB191; MNHN • 1 sh; sta. AB195; MNHN • 1 sh; sta. AS252; MNHN • 1 sh, 1 spm; sta. AB400; MNHN • 1 spm; sta. AB419; MNHN • 6 sh; sta. AB452; MNHN. — ‘Nord Caraibe’ • 1 sh; sta. AB567; MNHN. ‘Sud Caraibe’ • 1 sh; sta. AM038; MNHN • 1 sh; sta. AS075; MNHN • 1 sh; sta. AB360; MNHN.

GEOGRAPHIC DISTRIBUTION. — Antigua ( Zhang 2011); Guadeloupe ( Rolán & Fernández-Garcés 2015; Lamy & Pointier 2018; this study); Martinique (this study); Brazil: Ceará ( Bandeira 2019) to Santa Catarina ( Fernandes & Pimenta 2020).

BATHYMETRIC DISTRIBUTION. — Recorded depth in Guadeloupe: 8- 15 m. Recorded depth in Martinique: 0-26 m (live specimens at 2-17 m). Previous recorded depth in the West Atlantic: 0-45 m ( Fernandes & Pimenta 2015, 2020).

EMENDED DESCRIPTION

Shell sinistral, elongated, cyrtoconoid to nearly ovoid, slightly convex profile, up to 5.0 mm long, 1.9 mm wide, length/width ratio 2.4-2.9; adult shells reach at least 3.0 mm in length. Protoconch multispiral, conical/columnar, of 3.75-4.25 convex whorls, 0.37-0.44 mm long, 0.32-0.33 mm wide; embryonic shell dome-shaped, reticulated, covered by axial threads and c. 10-14 micro-spiral threads; larval shell with two spiral cords, situated at 31-41% and 54-71% of last whorl height, but adapical cord may disappear before transition to the teleoconch; c. 30- 35 nearly rectilinear to slightly sigmoid axial ribs. Teleoconch with up to ten whorls; two spiral cords (adapical and abapical) at the beginning, abapical one continuous to that of protoconch, and being slightly more prominent than adapical one in early whorls; median spiral cord often emerging at eighth or ninth whorl, rarely at seventh whorl, bordering the adapical cord, and reaching the same size of abapical cord (adapical one is slightly more prominent on body whorl) after nearly one whorl; rounded nodules of large size; 15-18 nearly orthocline to slightly opisthocline axial ribs on seventh whorl; shallow suture, with small sutural cord; subperipheral and adapical basal cords thick and nodulose, wavy abapical basal cord; two minute supranumerical cords may emerge near peristome, one between median and abapical spiral cords, the other between abapical and subperipheral cords; nearly circular to slightly rhomboid aperture, 0.56-0.74 mm long, 0.48-0.73 mm wide, length/width ratio 1.0-1.4; partly closed anterior canal, crossed in its base by projection of outer lip, 0.22-0.42 mm long, 0.12-0.26 mm wide, length/width ratio 1.0-2.5; deep posterior canal, almost detached from aperture. Golden to light brown protoconch; teleoconch light brown or cream, resembling wax or varnished, with adapical spiral cord considerably or faintly darker than abapical cord, which has whitish nodules; head-foot with whitish background, but red patches distributed along the entire extension (including the foot sole), except at the cephalic tentacles and the very anterior (11% of sole length) and very posterior (10% of sole length) extremities of the foot sole, which are translucent with small white dots.

REMARKS

Nanaphora leei was described from Southeast Brazil, supposedly with minor divergences when compared to the Brazilian records of the so-called N. verbernei , such as shell and protoconch size, shell shape and emergence of the median spiral cord of teleoconch ( Fernandes & Pimenta 2015). Because the Brazilian record of N. verbernei was misidentified (see above), the remaining doubt is whether it constitutes a new species or whether, after the evaluation of additional material, it also refers to N. leei . Some typical shells of N. leei (following the type material) were obtained from Martinique and Guadeloupe ( Fig. 14A, B ), as well as typical shells of the so-called N. verbernei from Brazil ( Fig. 14L ), comprising adult shell sizes from 3.0 to 5.0 mm (the holotype reaches 5.8 mm), shell shape more elongated to more ovoid depending on shell size ( Fig. 14 ), and emergence of the median spiral cord between seventh and ninth whorls (also depending on shell size, i.e., smaller shells have an earlier emergence of the median cord). Another evident variation is related to the color of the adapical spiral cord, which can be considerably light brown ( Fig. 14C, K ) or similar to the background ( Fig. 14L ), but never whitish as in most shells of true N. verbernei from Caribbean. With the current knowledge mainly limited to shell features, this high variation is conservatively considered as intraspecific of N. leei , which now has a known geographic distribution extended deeply into the Caribbean, including Antigua ( Zhang 2011). One shell from Bahamas ( Redfern 2013: fig. 368B), identified as Monophorus ateralbus Rolán & Fernández-Garcés, 1994 , is also possibly related to N. leei , but its broken apex precludes further comparisons.

Fernandes & Pimenta (2015) cited divergences between N. leei and M. ateralbus related to shell color and emergence of the median spiral cord. With the additional material of N. leei from the Caribbean, the adapical and median spiral cords of M. ateralbus are again considered darker than N. leei ( Fig. 14 ). The protoconch of M. ateralbus from Cuba has c. 0.6 mm long and five whorls ( Rolán & Fernández-Garcés 1994: fig. 7), although described as having four whorls (but using different counting of protoconch whorls), whereas typical shells of N. leei from Brazil and the material from Guadeloupe and Martinique often have four whorls (but up to 4.5 whorls) and reach 0.45 mm long. Small and ovoid shells of N. leei from Brazil (i.e., the so-called N. verbernei ), however, reach five whorls of protoconch (up to 0.55 mm long). The latter morph has obvious similarities but species-level divergences on radular features ( Fernandes & Pimenta 2019b) when compared to M. ateralbus from Cuba ( Rolán & Fernández-Garcés 1994), and the mitochondrial DNA also separates them (unpublished data – based on specimens of M. ateralbus from Florida, USA), although no typical specimens of N. leei are available yet to genetic studies. The single shell identified by Rolán & Fernández-Garcés (2015) as M. ateralbus from Guadeloupe, and followed by Lamy & Pointier (2018), actually refers to Triphora ellyae De Jong & Coomans, 1988 . Owing to the slight divergences indicated above (especially regarding the type of N. leei ), it is preferable to consider M. ateralbus absent from the Lesser Antilles, with a known range comprising Florida ( USA), Cuba and Bahamas ( Rolán & Fernández-Garcés 1994, 2007; Krisberg 2009; Redfern 2013), but further Caribbean material should be obtained to test this hypothesis.

The two live specimens of N. leei obtained from Martinique ( Fig. 19 G-H) have a reddish head-foot, bearing shells with a slightly dark adapical spiral cord of teleoconch ( Fig. 14K, M ); unfortunately, both specimens were stored dry during the expedition, avoiding DNA comparisons. The color of their soft parts is similar to that of the so-called N. verbernei from Brazil ( Fernandes & Pimenta 2019b: fig. 19A, B) and to the description of M. ateralbus ( Rolán & Fernández-Garcés 1994) , highlighting affinities between N. leei and the variable genus Monophorus , which has most (but not all) species described with a reddish head-foot ( Fernandes & Pimenta 2019b).

Figures

FIG. 14. — Nanaphora leei Fernandes & Pimenta, 2015:A, MNHN, sta. AS075, 5.0 mm; B, MNHN, sta. GS34 (KARUBENTHOS 1), 4.9 mm; C, MNHN, sta. AB191, 4.8 mm; D, E, MNHN, sta. AB260, 4.3 mm, 4.2 mm; F, MNHN, sta. AS252, 4.1 mm; G, MNHN, sta. AB197, 3.9 mm; H, MNHN, sta. AB567, 3.9 mm; I, MNHN, sta.AB195,3.9 mm;J, MNHN,sta.AB360,3.7 mm;K, MNHN,sta.AB400,3.7 mm;L, MNHN,sta.AS557,3.6 mm;M, MNHN,sta.AB419,3.0 mm.Scale bars:1 mm.

FIG. 15. — Nanaphora leei Fernandes & Pimenta,2015:A, MNHN,sta. AB197;B, MNHN,sta.AB567;C, E, MNHN,sta. AB360;D, MNHN,sta.AB419;F, G, MNHN, sta. AS557; H-J, MNHN, sta. GS34 (Karubenthos 1) (Fig. 14B). Scale bars: A-D, H, 100 μm; E-G, 200 μm; I-J, 500 μm.

FIG. 19. — Live triphorids from Martinique and Guadeloupe (marked with asterisk): A, B, Metaxia taeniolata (Dall, 1889), MNHN, sta. AD261; C-F, Monophorus olivaceus (Dall, 1889), MNHN, sta. GD21 (C), AB185 (D), AR461 (E, F); G, H, Nanaphora leei Fernandes & Pimenta, 2015, MNHN, sta. AB400 (G), AB419 (H); I, Nanaphora cf. verbernei (Moolenbeek & Faber, 1989), MNHN, sta. AB149. Credits: MNHN team.