Mesoptilus carpenteri, Guan & Prokop & Roques & Lapeyrie & Nel, 2016

Guan, Zhaoying, Prokop, Jakub, Roques, Patrick, Lapeyrie, Jean & Nel, André, 2016, Revision of the enigmatic insect family Anthracoptilidae enlightens the evolution of Palaeozoic stem-dictyopterans, Acta Palaeontologica Polonica 61 (1), pp. 71-87 : 77-78

Mesoptilus carpenteri sp. nov.

Fig. 4 .

Etymology: In honor of Frank Morgan Carpenter, who worked particularly on Palaeozoic insect fauna in the Museum of Comparative Zoology at Harvard University, Cambridge.

Holotype: MCZ 11253 , in unsorted Carpenter’s collection.

Type locality: Elmo , Oklahoma, USA.

Type horizon: Wellington Formation, Artinskian (early Permian).

Material.— Type material only.

Diagnosis.—Forewing anterior branches of CuA widely separated at their bases, with first one close to m-cua.

Description.—Forewing with anterior margin partly missing, wing 35 mm long, 10.2 mm wide; straight, concave ScP with several anterior branches reaching costal margin, each subdivided; area between ScP and costal margin with numerous crossveins and veinlets, 2.3 mm wide; ScP parallel to radius, 0.5 mm apart, probably ending ca. 17 mm from wing base; radial stem straight, with RP separating from RA 11.4 mm from wing base; RA strongly convex, straight and simple, ending 2.5 mm from wing apex; concave RP posteriorly pectinate, with seven main branches, resulting into eight branches ending on wing margin; RP and median vein separated but approximate with a short crossvein between them 12.7 mm from wing base; median vein slightly more convex than RP, divided into three straight and simple branches; presence of a brace m-cua between median vein and CuA; strongly convex CuA anteriorly pectinate with four main branches distinctly less convex than main stem of CuA; CuA separating from CuP 1.9 mm from wing base; concave CuP simple, curved with numerous crossveins between it and CuA in a broad area, 2.4 mm wide; area between CuP and posterior wing margin 2.0 mm wide; five visible weakly curved main branches of anal veins, a net of secondary veinlets and crossveins present in between; a dense net of rather straight crossveins between branches of all main veins, except in area between CuA and CuP, between C and ScP, and anal area where nets of more irregular cells are present.

Remarks.—This fossil can be attributed to the Anthracoptilidae on the basis of the presence of all the diagnostic characters of the family listed above. It differs from all the other representatives of the family, except Mesoptilus dolloi , Spargoptilon Kukalová, 1965 , and Homocladus Carpenter, 1966 , in the presence of a rather broad area between CuA and CuP with a dense net of small irregular cells. Mesoptilus carpenteri , M. dolloi , and Spargoptilon differ from Homocladus in the presence of much less branches of M and RP in the tegmina. Spargoptilon differs from Mesoptilus in the shorter part of CuA basal of brace m-cua, and narrower area between CuA and CuP. M. carpenteri differs from M. dolloi in the anterior branches of CuA more widely separated at their bases, with first one close to m-cua, and media ending with three terminal branches instead of four in M. carpenteri .

Stratigraphic and geographic range.—Artinskian (lower Permian), Oklahoma, USA.

Figures

Fig. 4. Forewing of anthracoptilid insect Mesoptilus carpenteri sp. nov. from Artinskian of Elmo, Oklahoma, USA, holotype MCZ 11253, photograph (A), line drawing (B).