Maculaferrum blaisi, Demers-Potvin & Szwedo & Paragnani & Larsson, 2020

Demers-Potvin, Alexandre V., Szwedo, Jacek, Paragnani, Cassia P. & Larsson, Hans C. E., 2020, First North American occurrence of hairy cicadas discovered in the Cenomanian (Late Cretaceous) of Labrador, Canada, Acta Palaeontologica Polonica 65 (1), pp. 85-98 : 88-91

Maculaferrum blaisi sp. nov.

Figs. 2 , 3, 4A.

Zoobank LSID: urn:lsid:zoobank.org:act:8F96A300-25A5-4F3E-BCFC-B5171A85A11D

Etymology: In reference to Roger A. Blais, who undertook the initial survey of the Redmond Formation in 1957.

Holotype: RMIP 2018.18 .24 (part), impression of a single isolated forewing either ripped in half or folded onto itself so that the middle area is hidden from view. The basal part consists in the majority of the pre-nodal area, and the apical part consists in the vast majority of the post-nodal area.

Type locality: Redmond no. 1 mine, near Schefferville, Labrador, Canada.

Type horizon: Redmond Formation, Cenomanian, Late Cretaceous.

Diagnosis.—In general view, forewing similar to forewing of Protabanini fossils, Tettagalma striata Menon, 2005 from the Aptian Crato Formation of Brazil and Protabanus chaoyangensis Hong, 1982 from the Jiulongshan Formation, Liaoning, China. Costal cell narrower basally than basal cell (as in Tettagalma ; in Protabanus costal cell about as wide as basal cell); single terminal RP longer than cell a6 (as in Protabanus ; in Tettagalma cell u3 distinctly shorter than cell a6); apical portion of stem CuA basad of nodal line minimally curving mediad (as in Protabanus ; in Tettagalma this section of stem CuA is distinctly curved mediad); CuA 2 with a sharp uniform curve apically (contrary to at most faint apical curves in Protabanus and Tettagalma ). Specimen also resembling some Meunierini, viz. Meuniera haupti Piton, 1936 from the Palaeocene quarry of Menat, France, and members of Tettigarctini such as extant Tettigarcta spp. from southern Australia, due to M and CuA joined by a m-cua cross vein at the apical extremity of the basal cell and CuA 2 running along nodal line up to clavus apex. However, it differs from Meunierini due to stem M forking closer to nodal line than to wing base; it also differs from Tettigarctini due to forking of RA not level with cross vein r and CuA 2 curving towards apex instead of base. Uniform curvature of CuA 2 seems apomorphic for Maculaferrum gen. nov. Round darker markings in apical cells, less distinct rounded spots in ulnar cells; appendix with minuscule striae (corrugations) exceeding ambient vein; punctate pattern on basal portion of forewing.

Description. —Total forewing length estimated at 20–23 mm; maximal forewing width 7.5 mm. Marginal membrane (appendix) present along entire margin apical of RA 1 to 1A terminal apex; ambient vein perfectly visible, criss-crossed by minuscule striae, from RA 2 to CuA 2 ( Figs. 2 , 3A 1, A 2); postclaval membrane present, narrow. Rows of tubercles present along segments of longitudinal veins, each projecting perpendicular to vein (Fig. 3A 3). Only short segment of the nodal line appears visible, parallel to CuA 2 (Fig. 3B). Round to oblong patches present in apical cells a1 to a8 and postnodal portion of ulnar cells u1 to u3 and medial cell, closer to cross veins ( Figs. 2 , 3C). Punctate pattern observed on much of pre-nodal area but absent from post-nodal area ( Figs. 2 , 3D).

Costal area of forewing straight at base, increasingly curved apically, apex relatively sharply curved, claval margin straight, apex of clavus slightly exceeding half of forewing length. Costal margin thick, veins of costal complex flattened to level of nodus. Stem vein Sc tightly adjoined and subparallel to stem R+M, fused with R+M merely apicad of apex of basal cell. Stem Sc+R short, about ¼ of length of basal cell, forked distinctly basad of nodal line and M forking; branch of Sc+R subparallel to costal margin, its prenodal section about 3 times as long as stem Sc+R; terminal Sc short, oblique, diverged slightly apically of nodal line. Branch RA forked at basal half of membrane, with three terminals: branch RA 1+2 slightly sinuous, RA 1 short, oblique, RA 2 subparallel to forewing anterior margin, RA 1 and RA 2 terminal apices distinctly basad of forewing

Fig. 3. Photomicrographs highlighting specific characters of the forewing of hairy cicada Maculaferrum blaisi gen. et sp. nov. (holotype, RMIP 2018.18.24) from the Cenomanian (Late Cretaceous) Redmond Formation, Labrador, Canada, extracted from the RTI file (see SOM). A. Highlights on striae along ambient vein and tubercles along longitudinal veins. Apical portion of the forewing, striae crossing ambient vein either side of apex, under specular →

apex; RA 3 reaching ambient vein slightly basad of forewing apex; RP forked from Sc+R basad of 0.3 of forewing length, reaching ambient vein with single terminal slightly basad of forewing apex. Stem M forked close to nodal line level (Fig. 3D 2, not clearly preserved), branch M 1+2 forked apicad of branch M 3+4 forking and apicad of RA forking; M 3+4 forked basad of RA forking. Stem CuA leaving basal cell distinctly curved at base, then arcuate, geniculately bent posteriad at nodal line, forked at level of nodal line; branch CuA 1 much longer than branch CuA 2, subparallel to branch M 3+4, then bent to ambient vein, to reach it at level of RA forking. CuP and claval fold straight, reaching margin merely basad of nodal line; 1A slightly sinuate, subparallel to CuP; 2A arcuate, relatively short; 3A fused to basal margin of forewing. Cross vein r slightly apicad of terminal RA 1; cross vein r-m oblique, at level of terminal RA 1; cross vein m oblique, connecting M 1+2 with terminal M 3, slightly basad of terminal RA 1; basal cross vein m-cua very short, connecting stem M with stem CuA at posterior apical corner of basal cell; apical cross vein m-cua oblique, connecting terminal M 4 with CuA 1 distinctly basad of terminal RA 1, basad of half of M 4 length, apicad of half of CuA 1 length. Basal cell about 4 times as long as wide, subrectangular. Costal cell about as wide as basal cell. Prenodal portion of cell u1 shorter than postnodal portion. Prenodal portion of cell u3 short (not clearly preserved). Cell a7 significantly shorter than other apical cells. Cell a8 slightly shorter than adjoining postnodal portion of cell mc.

Remarks.—During fossilization, the forewing was broken along the nodal line, and portions partly overlap. It means that much of the area surrounding the nodal line is not clearly preserved. It is very difficult to see the position of the branching of M into M 1+2 and M 3+4, but it seems to be very close to the margin of the preserved basal portion of the forewing. Considering the incomplete state of the specimen, a reconstruction of the entire forewing is presented alongside wings of living relatives Tettigarcta crinita and T. tomentosa ( Fig. 4 ).

Stratigraphic and geographical range.— Type locality and horizon only.

Figures

Fig. 2. Hairy cicada Maculaferrum blaisi gen. et sp. nov. (holotype RMIP 2018.18.24) from the Cenomanian (Late Cretaceous) Redmond Formation, Labrador, Canada. Habitus photograph (A1), extracted from the RTI file (downloaded from http://culturalheritageimaging.org/Technologies/RTI/ on 31 July 2019; see SOM) and interpretative line drawing (A2). Wing venation terminology after Moulds (2005). Abbreviations: A, anal vein; a, apical cell; av, ambient vein; bc, basal cell; C, costa; Cu, cubitus; CuA, cubitus anterior; CuP, cubitus posterior; M, media; M1+2, two anterior branches of M; M3+4, two posterior branches of M; m, medial cross vein; mc, medial cell; m-cua, mediocubital cross vein; RA, radius anterior; RP, radius posterior; r, radial cross vein; r-m, radio-medial cross vein; Sc, subcosta; u, ulnar cell. Black lines, striae along wing apex; grey lines, tubercles along apical vein segments; dashed line, visible portion of nodal line.

Fig. 4. Comparison of hairy cicada Maculaferrum blaisi gen. et sp. nov. (holotype RMIP 2018.18.24) from the Cenomanian (Late Cretaceous) Redmond Formation, Labrador, Canada, with forewings of extant relatives (B, C). A. Interpretative drawing of M. blaisi gen. et sp. nov. (holotype RMIP 2018.18.24) in pre-burial state, based on extant and extinct relatives. B. Left forewing of male Tettigarcta crinita Distant, 1883 from southern Victoria,Australia; NMV HEM5660 in dorsal view. C. Left forewing of female Tettigarcta tomentosa White, 1845 from Tasmania, Australia; NMV HEM476 in dorsal view. Note colouration pattern on post-nodal half: round patches near junction of terminal longitudinal veins with ambient vein, a larger darker round patch in cell a2, smaller irregular patches along more basal segments of longitudinal veins, and large oblong to irregular patches along cross veins and short segment of M1. Abbreviations:A, anal vein; a, apical cell; av, ambient vein; bc, basal cell; C, costa; Cu, cubitus; CuA, cubitus anterior; CuP, cubitus posterior; M, media; M1+2, two anterior branches of M; M3+4, two posterior branches of M; m, medial cross vein; mc, medial cell; m-cua, mediocubital cross vein; RA, radius anterior; RP, radius posterior; r, radial cross vein; r-m, radio-medial cross vein; Sc, subcosta; u, ulnar cell.