Bubalopa Stål, 1869

Flórez-V, Camilo & Evangelista, Olivia, 2021, A revision of the treehopper genus Bubalopa Stål illuminates the systematics of Hyphinoini (Hemiptera: Auchenorrhyncha: Membracidae), Zootaxa 5052 (4), pp. 529-551 : 535-536

Bubalopa Stål, 1869

Bubalopa Stål 1869 c: 255; Funkhouser 1927: 117 ( Darninae ); Metcalf & Wade 1965: 701 ( Darninae ); Deitz 1975: 72 ( Darninae : Hyphinoini ); McKamey 1998: 476 ( Darninae : Hyphinoini ).

Diagnosis: Large (> 10mm), robust. Suprahumeral horns prominent, tricarinate, diagonal with respect to median carina, truncate apically; posterior process not reaching forewing apex. Forewings entirely exposed, strongly coriaceous at basal 1/2, membrane adjacent to veins punctate throughout; all punctations with adjacent setae; forewing membrane setose on basal 2/3, mostly glabrous at apical 1/3, bearing supernumerary veins. Femora lacking cucullate setae, metatibia with three complete, distinct rows of cucullate setae.

Description: ADULTS. Large (> 10mm), robust. Ochraceous yellow to brown with dark punctation; forewings opaque, amber to dark brown, hindwings smoky hyaline. Surface: Head, pronotum and forewings densely punctate, punctations large and deep, each with single adjacent silver seta. Ventral area of head, thoracic sclerites and legs covered in shiny pubescence. Basal 1/2 of forewings distinctly sclerotized, punctations covering 4/5 of basal cell 1 (R), 1/2 to 2/3 of basal cell 2 (M) and 1/3 to entire basal cell 3 (Cu). Head: Subtriangular, almost as wide as long; anterior margin of vertex widely arched, posterior margin trapezoid; supra-antennal ledges slightly to distinctly sinuous or indented; anterior margin of frontoclypeus triangular, apex acute to slightly round, posterior margin arched. Thorax: Pronotum: dorsomedian carina percurrent, sharper from basal 1/3 to apex of posterior process; suprahumeral horns prominent, prismatic, 1–3x as long as wide basally, moderately curved, diagonal with respect to median carina both anteriorly and dorsally; each horn bearing three sharp longitudinal carina: anterior carina emerging from above supraocular callosities, lateral and dorsal carina emerging from above humeral angles, all three converging to horn apex; dorsal outline of posterior process slightly curved to strongly sinuous past humeral angles, gradually declining along posterior 1/3; dorsal hump occasionally present at middle; deep semicircular impressions past humeral angles and above clavus in lateral view; posterior process acute, not extended above apex of forewings. Forewings entirely exposed, strongly coriaceous at basal 1/2; all punctations with adjacent seta; membrane adjacent to veins punctate throughout, cell membrane at apical 1/3 glabrous; vein R initially divided into R 1+2+3 and R 4+5, one s, one r-m and two m-cu crossveins present, crossvein s distad of r-m, several supernumerary crossveins in apical 1/3. Hind wing with four apical cells, one r-m and one m-cu crossveins. Femora lacking cucullate setae; dorsal surfaces of tibiae sulcate; metathoracic tibia with three complete longitudinal rows of cucullate setae, row III single basally, double or triple on apical third; first metathoracic tarsomere lacking cucullate setae on plantar surface, cucullate setae present at apex. Abdomen: terga III–V or III–VI with a pair of dorsal scars ( Figs. 7A, D ; 8A, F ). Male genitalia: lateral plates fused with pygofer. Subgenital plates somewhat pear-shaped, inflated, lobes with dorsal hump in lateral view, contour sinuous in ventral/dorsal view; aedeagus U-shaped, slender, bearing minute teeth along dorsal surface ( Fig. 7 ). Female genitalia: Second valvulae blade shaped, two prominent teeth on apical third ( Fig. 8 ).

4 TH /5 TH INSTAR NYMPH (based on fourth/fifth instar nymphs of B. furcata ) ( Fig. 6 ): Vertex with 10 scoli arranged in 5 bilaterally symmetric pairs along the upper (8) and inferior (2) border. Tuberculate chalazae numerous, varying in size, broadly distributed on prothorax, lacking setal portion or very reduced; anteroventral margin at base of forewing pads, abdominal scoli, ventro-lateral margins of abdominal terga, and anterodorsal and posterodorsal margin of tibia. Prothorax well developed, tall, pair of scoli on metopidium (=premetopidium scoli sensu McKamey et al. 2015); anterior projection bearing two robust, conical scoli curved apically (=postmetopidium scoli sensu McKamey et al. 2015); posterior process triangular, reaching anterior margin of metanotum; suprahumeral process buds flap-like, folded posteriorly onto sides of prothorax. Meso- and metathorax with a pair of scoli each.Abdominal terga III–V with pair of distinctly tall, laterally divergent, and stout dorsal scoli, terga VI–VIII with pair of small spinelike scoli, segment IX tubular, elongate with dorsal length almost equal to combined lengths of segments IV–VIII, bearing a pair of apical spine-like scoli.

Distribution: species of Bubalopa are restricted to the Northern Andes in Colombia and Venezuela ( Fig. 11 ). COLOMBIA: Antioquia: Medellín (Corregimiento Santa Elena); Boyacá: Villa de Leyva (SFF Iguaque). VENEZUELA: Trujillo: Boconó.

Species included (3):

Bubalopa furcata ( Fairmaire, 1846)

B. obscuricornis Stål, 1869

B. iguaque Flórez-V and Evangelista sp. nov.

Remarks. Members of Bubalopa are distinguished by (1) their entirely exposed forewings, exceeding the length of the posterior pronotal process, and (2) apical supernumerary forewing veins, which yield a reticulate aspect. Their placement in Hyphinoini was inferred based on forewing venation, leg chaetotaxy, and traits from late instar nymphs, as previously discussed.

The distribution and appearance of scoli and other characters in the fourth-fifth instar of B. furcata is almost identical to that of Alcmeone robustus ( Lencioni-Neto and Sakakibara 2013) . Dorsal pronotal impressions in the form of two small circular impressions can be observed in the adults of B. furcata and A. robustus . This feature is thought to be remnants of the two large apical scoli located on the pronotal process of last instar nymphs ( Lencioni-Neto and Sakakibara 2013, Fig. 6 , p. 472; Fig. 5B ). This appears to be the case in B. furcata , whose immatures also have large pronotal scoli and nearly identical pronotal scars in adults. These scars, although minute, can be easily distinguished in the middle of the dorsum, with one impression at each side of the dorsomedian carina, posterior to the suprahumeral horns ( Fig. 5B ).

Large oval pits on the dorsolateral portion of the abdominal terga III–V are a distinguishing feature of Bubalopa ( Figs. 7A, D ; 8A, F ; 10C ), although also observed in other Darninae groups. Deitz (1975) commented that spots, fenestrae or tuberosities were present in members of Cymbomorphini and Hyphinoini , and identical pits were described for A. robustus ( Lencioni-Neto and Sakakibara 2013) . The oval pits seem to be a remnant of the large nymphal scoli in Bubalopa and Alcmeone , as they share the same location in both nymphs and adults. Further observations can help confirm whether these pronotal and abdominal scars in adults result from nymphal traits that share a topological correspondence.

The prominent abdominal apodeme is a remarkable feature of Bubalopa . The shape of these apodemes varies among species and can be relatively inflated and extended to the posterior margin of the abdominal segment IV (e.g., B. iguaque sp. nov., Fig. 10C ). These structures have been virtually unexplored in treehopper systematics, except for one previous study which incorporated this information into a phylogenetic reconstruction of the tribe Darnini ( Roy et al. 2007) Roy et al. ’s findings demonstrate that these abdominal characters can offer information useful for refining the classification of these darnine groups.

Nymphal traits are reported for the first time for B. furcata , but immature stages of other Bubalopa species remain unknown. There is remarkable variation in the size of scoli between early and late instars, as most scoli undergo a significant reduction in size, albeit with important distinctions between hyphinoine genera ( Figs. 1 , 3 ). In early instars of B. furcata , the scoli on the head, metopidium, mesothorax and VI–VIII abdominal segments turn into minute spine-like processes in older nymphs ( Fig. 3 ). Contrastingly, in H. obliqua , the same scoli remain large during development, covered in tuberculate chalazae ( Fig. 1 ). Although the scoli on the head of B. furcata appear to be chalazae in the late instar, these structures seem to arise from the large scoli observed in the early instars.

Morphological features relevant to species-level recognition in Bubalopa

Species of Bubalopa are mainly distinguished by their body color (head, pronotum, forewings, and legs), as well as the overall appearance of their pronotum, e.g., suprahumeral horns and posterior process. Most relevant traits pertain to the head, pronotum, and genitalia: the shape, size and orientation of the suprahumeral horns, the shape of the frontoclypeus, suprantennal ledges and dorsal pronotal outline, and certain structures of the male genitalia such as the parameres. Bubalopa is the only genus in Darninae to exhibit reticulate forewings, which resemble the wings of species of Membracinae : Hypsoprorini, Centronodinae , Centrotinae : Centrodontini, and Nicomiinae. The extent and number of supernumerary veins can vary among species, and while this trait is also expected to have a degree of intraspecific variation, this could not be assessed based on the few representatives available for examination. The orientation and length of the suprahumeral horns can have inter- and intraspecific variation.Additionally, parameres in Bubalopa are broad throughout, but the apex varies among species, and may be either bifurcated and T-shaped or truncated with a lateroventral projection. The aedeagus does not vary greatly between species, but it may vary in width and length.

Figures

FIGURE 1. Live specimens of Hyphinoe obliqua (Walker, 1858). Nymphs: A) and B) 1/3rd instar, C) 4/5th instar, D) Last instar exuvia.

FIGURE 3. Live specimens of Bubalopa furcata. Nymphs: A) habitus of an early instar. B–D). Fourth/fifth instar nymph: B) habitus in lateral view, C) 4/5th instar nymph resting near the stipule of its host plant (Senna pistaciifolia), D) habitus in lateral view. Adult: E) frontal habitus, F) lateral habitus.

FIGURE 5. Bubalopa furcata (Fairmaire, 1846). Male: (A–E) A) Frontal view. B) Dorsal view, pronotal scars indicated by a rectangle. D) Lateral view. E) Frontolateral view. Female: (E–H). E) Frontal view. F) Dorsal view. G) Lateral view. H) Frontolateral view.

FIGURE 6. Bubalopa furcata (Fairmaire, 1846). A) male abdomen, oval pits indicated by a rectangle. B) Female, ventral view. Fourth-fifth instar nymph: C) Frontal view. D) Head, anteroventral view. E) Head, ventral view. F) Lateral view, left side. F) Lateral view, right side. G) Frontolateral view. H) Dorsal view. ach: lateral abdominal chalazae; as: abdominal scoli; hs: head scoli; mss: mesothoracic scoli; mts: metathoracic scoli; pms: premetopidium scoli; pos: postmetopidium scoli; shb: suprahumeral horns bud; sps: small spinelike scoli.

FIGURE 7. Male of Bubalopa furcata (Fairmaire, 1846). Abdomen:A) Dorsolateral view, oval pits indicated by a rectangle, B) ventral view, C) close-up of abdominal spiracles, D) close-up of scars on abdominal terga III and IV, E) lateral view. F) Pygofer in lateral view. G) Subgenital plate in ventral and dorsal view.Aedeagus: H) Lateral view, I) caudal view, J) anterolateral view. K) Subgenital plate in lateral view. Parameres: L) Lateral view, M) dorsal view, N) ventral view.

FIGURE 8. Female of Bubalopa furcata (Fairmaire, 1846). Abdomen: A) Dorsal view, B) ventral view, C) lateral view, oval pits indicated by a rectangle, D) Pygofer. E) Close-up of spiracle. F) Close-up of scars on terga III–V. First valvulae: G) lateral view, H) close-up apex. Second valvulae: I) lateral view, J) close-up apex.

FIGURE 10. Male of Bubalopa iguaque Flórez-V and Evangelista sp. nov. Abdomen: A) Dorsolateral view, B) ventral view, C) lateral view, D) pygofer. E) Subgenital plate in ventral view. Aedeagus: F) lateral view, G) caudal view, H) anterior view. Parameres: I) Lateral view, J) dorsal view.

FIGURE 11. Distribution map of Bubalopa furcata, B. iguaque sp. nov., and B. obscuricornis.