﻿Three new monobasic genera and three new species of the New World treehopper tribe Acutalini (Hemiptera, Membracidae, Smiliinae) with a key to all genera

﻿Abstract Three new genera in Acutalini are described, two of which have two discoidal cells (R2+3 and M) in the forewing, as in Euritea Stål. Ceresinoideazackigen. nov. et sp. nov., from Guatemala, differs from other acutalines in having a pair of suprahumeral spines and a stepwise convex pronotum in lateral view. Quinquespinosaseptamaculagen. nov. et sp. nov., which is widely distributed in South America, differs in having a basal cell M and three posterior pronotal spines. Tectiformaguayasensisgen. nov. et sp. nov., from Ecuador, has the pronotum strongly tectiform throughout. A key to all genera of Acutalini is provided.


Introduction
Acutalini belongs to the second most speciose treehopper subfamily, Smiliinae (Bartlett et al. 2018), with 750 species. Acutalini, however, is a species-poor tribe, with only 26 described species, but ranges from Canada to Brazil and Peru. At the time of Deitz's (1975) revised classification of the New World Membracidae, Acutalini contained only three genera: Acutalis Fairmaire (nine species), Euritea Stål (three species), and Thrasymedes Kirkaldy (six species). All of these species were listed by McKamey (1998) and are elongate with a low, dorsally convex pronotum that lacks suprahumeral spines (McKamey 1998 also listed Acutalis terminalis Walker, which was designated as the type species of Germariana Sakakibara 1998). Acutaline genera differ from each other by forewing venation patterns, and differ from other Smiliinae in the following combination of characters: having the pronotum not, or only slightly, overlapping the forewing in repose, having veins R, M, and Cu separate near the wing base, vein R 2+3 present as a distinct branch of R, vein R 4+5 confluent with M distad of M fork, and crossveins s and m-cu present (Deitz 1975). Dietrich et al. (2001) also included, as another feature, a forked anal vein in the hind wing (as in Fig. 39), which is shared with non-smiliines but only two other tribes of Smiliinae (Ceresini and Micrutalini). Sakakibara (1997) described another genus, Bordonia (preoccupied, replaced by Bordoniana Sakakibara 1999), with five species, and also the genus Cornutalis, with two species. Both genera have a pair of short, laterally directed suprahumeral spines. Flórez-V (2017) described another species of Cornutalis from Colombia that has a pitted pronotum with stout suprahumeral spines directed dorsoanteriorly.
In a recent sequence-based phylogenetic study (Evangelista et al. 2017), Micrutalini and Acutalini had intermixed clades and were, together, the sister group of Cymbomorphini, not with Ceresini or other Smiliinae. McKamey and Wallner (2022) described the immature stages of Acutalini and Micrutalini.
In the present paper, three new genera and three new species are described. Two of these new genera would follow Sakakibara's (1997) key to Euritea because they have two discoidal cells in the forewing. Nevertheless, they differ from Euritea in important respects: they have suprahumeral spines or are strongly tectiform. A key is provided to all genera of Acutalini.

Material and methods
In quoting labels, quotation marks separate labels and a vertical line separates lines on a label. Terminology for general morphology, forewing venation, and leg chaetotaxy follows Deitz (1975). A Leica MZ12 stereomicroscope was used to examine structures. The body length was measured using a digital micrometer. A manual 5 mm micrometer was used to determine ratios between other, shorter distances.
The abdomen was detached, macerated in a warmed 10% KOH solution for 24 hours at room temperature, bathed in water, then acetic acid to stop the reaction. After dissection, structures were stored in a glass microvial containing glycerin and pinned beneath the specimen.
Images were taken with a Canon 5D SLR camera with an adjustable 65 mm macro lens using Capture One Pro ver. 10.1.2, 64 Bit, aided by CamLift ver. 2.9.7.1. The specimens were lit using two adjustable Dynalite MH2050 RoadMax flash heads, each attached to a Manfrotto 244 arm. The light was diffused using a simple, lampshadestyle cone of translucent paper between the specimen and light sources. After individual "slices" were photographed, they were compiled into a single, composite image using Zerene Stacker -USDA SI-SEL Lab Bk imaging system, ver. 1.04. Stacked images were enhanced and edited in Adobe Photoshop CSS Extended ver. 12.0. The scale bars were generated through Photoshop directly from the metadata of the photo.
Specimens examined will be deposited in the following Institutions: 1 Forewing without discoidal cells (Fig. 1) (Fig. 4)  Description. Head. Vertex glabrous, without ridges or rugae, slightly concave especially at lateral margins and around ocelli; ocelli circular, slightly closer to eyes than to each other; dorsal margin weakly convex but not attaining dorsal margin of eye, which is elevated (Figs 6, 8); frontoclypeus apically rounded, its sutures arched to midpoint. Pronotum. Smooth, glabrous, elevated, strongly convex in lateral view, with acute suprahumeral spines. Wings. Forewing (Figs 5,9) with 2 adjacent discoidal cells (R 2+3 and M), 2 m-cu crossveins. Hind wing with 1 r-m and 1 m-cu crossvein, with forked anal vein. Legs. Metathoracic tibia with cucullate setae in row I double, row II and row III complete and single.
Distribution. Neotropical: Central America. Etymology. The name, which is feminine, is based on the superficial similarity of the type species to inornate members of the tribe Ceresini.
Distribution. Neotropical: South America. Etymology. The name is feminine and refers to the five (quinque-) spines (-spinosa) on the pronotum.

Notes.
Whereas Euritea has two m-cu crossveins in the forewing, this new genus has only one. Its veins M and Cu separate and diverge at base, then instead of being bridged with an m-cu crossvein as in Euritea and Ceresinoidea, its veins M and Cu completely fuse into a single vein (enclosing basal cell M; Figs 21, 24), then separate again distally as in all other Smiliinae. This unusual venation at the wing base is the same on all wings of all 17 specimens, so is not an aberration. Another interesting feature of this genus is the confluence with the anterior branch of R with M for a short distance, in the hind wing (Fig. 21); this trait also occurs in Ceresini as well as in other Smiliinae.

Quinquespinosa septamacula sp. nov. https://zoobank.org/7DA19879-CE17-4901-9280-B6BF0130266E Figs 18-31
Diagnosis. Frontoclypeal sutures bordered by conspicuous black spots; pronotum with pair of dorsal pale longitudinal stripes dorsally and another pair more laterally, at level of suprahumeral spines; posterior portion of pronotum with 7 distinct dark marks (Figs 22,24): 2 pairs, one pair straddling the apical middle spine and the second pair more laterally, behind the bases of apical lateral spines, and one on each of the 3 posterior spines.
Material examined. Holotype ♂ (EPNC) with labels "ECUADOR: NAPO: Reserva Ethnica | Waorani, 1 km. S Onkone Gare | Camp Trans. Ent 9. Feb 1995 | 220m | 11-Feb-1995 00 °39'10"S 076 °26'W | T.L Erwin: et al ", "Insecticidal fogging of mostly bare | green leaves, some with covering | of lichenous or bryophytic plants in | terre firme forest At Trans 1, | Sta. 2 Project MAXUS Lot 1021." and red "HOLO-TYPE | Quinquespinosa | septamacula | S.H. McKamey." Non-types: 16 specimens. Two (USNM) have the same data as the holotype except as noted: 1♀ 8-Feb-1996 Lot 971; 1♀ 29-Jun-1994 lot 755. The other specimens have the same data as the holotype except coordinates 00 °39'25.7"S 076 °27'10.8"W and otherwise noted: Notes. There is variability in the length of the suprahumeral spines and the size of the four preapical black spots (compare Figs 18 and 22); neither is correlated to body size or gender. The pronotum of the specimen from French Guiana (MNHN) is unique in being black only on the tips of the five spines, lacking the four other black marks altogether and is considered to be a variety, possibly geographical, of the same species.
The 13 specimens from Ecuador fogging samples in the Reserva Etnica Waorani were collected in January, February, June, July, and October, from 1994-1996. The Peruvian and French Guiana specimens were collected in September (1991) and November (1969, and the Brazilian specimen in March (1979). Considered together, the only gaps are April, May, August, and December. The April-May gap possibly represents the growth of a second generation but the one-month gaps are probably too short to indicate other generations. Other explanations are sampling error, annual or seasonal fluctuations in climate, or that the adults are present throughout the year at least somewhere in their large range.
All specimens were collected by insecticidal fogging of the tree canopy (one from inundation forest and the others from terre firme forest) except the specimen from French Guiana, which was collected at a light trap. Although various leafhoppers feed on bamboo, no treehoppers have been found feeding on it, so the bamboo record for the Peruvian specimen is probably not its host plant. Diagnosis. This is the only acutaline genus with the pronotum tectiform throughout. Description. Overall body slender (Fig. 34). Head. Vertex inclined slightly forward, aligned with steep pronotal metopidium (Fig. 32); head vertex uneven, slightly swollen just ventrolateral of ocellus, glabrous, dorsal margin weakly sinuate, not attaining dorsal margin of eye, which is elevated (Fig. 33), ventral margin including frontoclypeus evenly convex ventrally with and convex, narrow vertical carina, its sutures evenly arched to middle; ocelli slightly oblong, divergent dorsally, slightly closer to each other than from eye (Fig. 33). Pronotum. Elevated anteriorly (Fig. 32), lacking suprahumeral spines (Figs 33, 34), laterally compressed and strongly tectiform from top of metopidium and posteriorly (Figs 32,33); metopidium in lateral view steeply inclined, gradually convex, then descending in straight line to apex; apex extends to mid-point between veins Cu and M 3+4 (Fig. 32). Wings. Forewing (Fig. 39, top)  adjacent discoidal cells (R 2+3 and M), 2 m-cu crossveins. Hind wing (Fig. 39, bottom) with 1 r-m and 1 m-cu crossvein, with forked anal vein. Legs. Metathoracic tibia with cucullate setae row I double, row II and row III complete and single.
Distribution. Neotropical. Etymology. The name is feminine and based on the strongly tectiform pronotum. Notes. The forewing venation, with two discoidal cells, is almost identical to that of Euritea, the only difference being that in Euritea, the two discoidal cells are not adjacent to each other. The dorsomedial carina of Cornutalis andinum Flórez-V (2017) and Ceresinoidea zacki are tectiform, but in the new genus Tectiforma the entire pronotum is tectiform, attaining a much greater height above the humeral angle, so these cannot be confused for one another even without considering differences in forewing venation.
Description of male. Measurements (mm). Length with forewing in repose 6.7; width across humeral angles 2.2; height in anterior view 2.9. Pronotum. As described for genus. Terminalia. Pygofer including lateral plate subquadrate in lateral view Figure 39. Tectiforma guayasensis sp. nov. holotype, wings, showing the two discoidal cells in the forewing and the forked anal vein in the hind wing.