Glenurus incalis Banks, 1922

Machado, Renato Jose Pires, 2020, Rediscovery of Glenurus incalis Banks (Neuroptera: Myrmeleontidae), and notes on the Brazilian species of Glenurus Hagen, Zootaxa 4858 (1), pp. 135-143 : 137-140

Glenurus incalis Banks, 1922

As mentioned previously, G. incalis is known only by the female holotype from Chanchamayo Peru, but herein I report four new specimens, another one from Peru and other three from the Amazon region in Brazil ( Fig. 5 ). The species is thoroughly redescribed below based on these four specimens and high-resolution images of the holotype.

Lengths: forewing: 41.5–44.5 mm; hind wing: 43–47 mm.

Head ( Fig. 3 ): Labrum and clypeus mostly dark brown, but lateral margins light brown; set with pale setae. Frons below antennae light brown with medial region dark brown, space between and above the antennae dark brown; set with few short pale setae. Gena light brown. Vertex raised; mostly brown with a medial longitudinal and medial transversal lines dark brown; set with short black setae. Ocular rim setae absent. Antennae clavate; more than three times longer than pronotum length; distance between antennae about the same size of scape width; scape and pedicel brown to dark brown; 49–51 flagellomeres about as long as wide, except by the basal one, about twice longer than wide, and the apical ones, much wider than long; flagellum brown but darkening towards the apex; all segments set with short black setae. Mandible light brown with internal margin and apex black. Maxillary palpi light brown except by the last two distal segments, dark brown. Labial palpi light brown except by the distal segment, dark brown; distal palpomere fusiform, palpimacula oval-shaped, located medially.

Thorax ( Fig. 3 b–c): Pronotum slightly longer than wide; posterior margin wider than anterior; subapical furrow present; mostly dark brown, except by a pale longitudinal stripe medially and the area distal to the furrow, brown to pale; set with long black setae. Meso and metanotum dark brown, except by a pale longitudinal stripe medially (stripe fading out in the metascutellum and sometimes completely absent, making it entirely dark brown); set with white setae and few black ones at the anterior margin of the mesoprescutum. Pterothoracic pleura entirely dark brown, except by small pale-yellow marks at the base of the wings; set with long white setae, and a few long black setae on the anterior margin of the mesothorax.

Wings ( Fig. 2b ): Elongate and with apex acute. Forewing shorter and wider than hind wing. Anterior Banksian line present in both wings but more evident in the forewing; posterior Banksian line absent in both wings. Sc, RA and Cu veins intercalating dark brown and pale areas, remaining veins entirely dark brown or white on the white apical spots; beset with short black setae. Forewing: membrane mostly hyaline except for a large transversal preapical brown band, apical and posterior margins distal to the transversal band also brown, end of CuP+1A with a small curved brown mark, small brown infuscations at the base of crossveins around RA, and poststigmal area mostly white. Cubital fork basal to Rs origin; seven to eight presectoral crossveins; subcostal veinlets mostly simple, but the ones near the junction between Sc and RA forked; crossveins at the prefork area simple; prefork area about twice wider than posterior area. Hind wing membrane hyaline except by the apical third brown; brown area with three white marks: two at the hypostigmal cell level (one at the anterior margin and the other at the posterior margin and slightly larger) and the largest one on the apical region, comprising most of the anterior margin and brown indented on the posterior area. One presectoral crossvein. Prefork and posterior areas about the same width

Legs ( Fig. 3a, c ): Tibia and femur about the same size and slightly longer than tarsi, (hind leg with tibia and femur about twice longer than tarsi). Coxa dark brown basally and pale apically, remaining segments mostly pale, except by small brown dots on the base of the setae, and the dark brown apex of the femur, tibia and T5; femur sometimes with dark brown mark near the base. All segments covered with black setae, except by the coxa with white setae. Tibial spurs long, passing T2 apex; tarsomeres length: T2, T3, and T4 about the same length, T1 as long as T2 and T3 combined, and T5 slightly longer than T1; claws shorter than half of T5 length. Foreleg: sense hair relatively short, only slightly longer than the regular setae; tibia with a patch of antennal cleaning setae on the apical region.

Abdomen: All sclerites dark brown, except by the tergites 1 and 2 with a pale medial longitudinal line, and the base of tergites 4–6 pale. All sclerites covered by short black setae, and white setae on the pale areas of the tergites, and first and second segments covered by long white setae

Female Terminalia ( Fig. 4 ): Ectoproct rounded, set with thin black elongate setae dorsally and few thickened setae on the ventral area, in lateral view. Lateral gonapophyses smaller than ectoproct in lateral view, beset with thickened setae, which are slightly longer than the ones on the ectoproct. Tergite IX thin dorsally but broadening towards the ventral area in lateral view, set with short black setae and a row of thickened setae on the ventral margin. Sternite VIII short, in ventral view rectangular and with the distal margin straight. Pregenital plate small and conical. Posterior gonapophyses short with posterior margin rounded, covered with long black thickened setae, longer than the ones at the lateral gonapophyses. Anterior gonapophyses absent. Gonapophyseal plates elongate and parallel. Spermatheca with the distal half broader and darker, than proximal half.

Male Terminalia: Unknown.

Comments: Among the Brazilian species of Glenurus , G. incalis can be easily identified based on the presence of a large brown stripe on the forewing, the presence of a large indented white mark apically in the hind wing, and the presence of a single white mark at the posterior margin within the brown area in the hind wing ( Fig. 2b ) ( G. peculiaris presents two white marks). Within the whole genus, G. incalis seems more similar to G. proi Navás, 1930 (known from Costa Rica, Honduras and Mexico) based on the indented white mark on the hind wing. However, they can be distinguished based on the pterothorax pleura color: entirely dark brown in G. incalis , but sharply divided in a dorsal dark brown line and a ventral pale brown line in G. proi ( Stange 2002) .

As mentioned above, G. incalis is the least known species of the genus, and until now it was only recognized based on the female holotype from Peru. The holotype was collected in Chanchamayo in the Junín department in the Peruvian Amazon. Herein we report a new specimen also from Junín, at the Satipo valley, and another three specimens from the Brazilian Amazon, one from the Rondônia state, municipality of Vilhena, and the other two from the Amazonas state, with records for the municipalities of Manaus and Itacoatiara. Both places in the Amazonas states are located in the center of the Amazon basin, on the northern shore of the Amazon river. These new distribution records considerably expand the distribution of G. incalis , suggesting that the species could be widespread throughout the Amazon forest.

Examined specimens. Brazil: Amazonas: Itacoatiara, Fazenda Aruanã , AM 010 , Km 215, 28–29.ix.1992, 21:00–22:00h, Motta C.S., Peralta F.A., Telos B. R., Hutchings R.S.G., Hamada N. (1♀ INPA); Manaus , 27.viii.1962, K. Lenko (1♀ INPA) ; Rondônia: Vilhena, 12º34’S– 60º03’W, 615m, 11.ix.1999, Coleção Embrapa CPAC no 17484. (1♀ Embrapa-DF); Peru: Junín: Chanchamayo, N. Banks, Type 12030, MCZ-ENT 00012030 (♀ holotype MCZ); Satipo Valley , 600m, vii–viii.1987 (1♀ DZUP) .

Figures

FIGURE 2. Glenurus wings, a: G. heteropteryx forewing; b: G. incalis fore and hind wing; c: G. peculiaris fore and hind wing. Scale bar = 5 mm.

FIGURE 3. Glenurus incalis, a: head, frontal view; b: head and thorax, dorsal view; c: head and thorax, lateral view. Scale bars = 1 mm.

FIGURE 4. Glenurus incalis female terminalia, a: terminalia, lateral view; b: terminalia, ventral view; c: spermatheca. e = ectoproct; gp = gonapophyseal plate; lg = lateral gonapophysis; pg = posterior gonapophysis; pp = pregenital plate; S = sternite; T = tergite.

FIGURE 5. South America map showing all the known records of Glenurus incalis, and the Brazilian records of Glenurus heteropteryx and Glenurus peculiaris.