Hebridea Willemse, 1926

Hugel, Sylvain, 2012, Review of Hebridea Willemse, 1926, an endemic genus of grasshoppers from Vanuatu (Orthoptera, Caelifera) with the description of a new species from Malekula, Zoosystema 34 (2), pp. 267-277 : 268-270

Genus Hebridea Willemse, 1926

Hebridea Willemse, 1926: 528 .

TYPE SPECIES. — Hebridea rufotibialis Willemse, 1926 by original monotypy.

OTHER SPECIES INCLUDED. — Hebridea amedegnatoae n. sp.

DISTRIBUTION. — Vanuatu: Espiritu Santo, Malekula, Erromango.

DIAGNOSIS. — Body cylindrical, elongated. Head sub conical; frons strongly oblique ( Fig. 1C, H ). Frontal sulcus shallow but distinct above antennae ( Fig. 1B, G ). Fastigium verticis angulose, almost pyramidal; with a weakly distinct median carinula ( Fig. 1B, G ). Antennae filiform, long; distal half flattened; with about 20 articles ( Fig. 1A ). Prn cylindrical; anterior and posterior margins rounded ( Fig. 1B, G ); median carina weakly distinct in the prozona and metazona; no lateral carinae in adults; lateral lobes posterovental angle straight ( Fig. 1C, H ). Episternum large, sub triangular ( Fig. 1C, H ). Prosternal process strong, vertical, transverse, trilobate ( Fig. 2A, B ). Mesosternal interspace open, narrow; mesosternal lobes rounded, about as long as wide; metasternal interspace closed, triangular ( Fig. 2A ).Tympanum large. Hind knees about reaching abdomen apex. Hind femur ( Fig 1D, I ) upper basal lobe longer than lower basal lobe; fishbone pattern distinct; carinae of hind femur obtuse, smooth; knee lobes rounded. Hind tibia distinctly shorter than hind femur; outer apical spine present, nine inner and outer spines (including the apical spines). Brachypterous. FW reaching the middle of the 3rd abdominal tergite; HW about as long as FW.

Male. Penultimate abdominal tergite (tergite 10) hind margin interrupted medially, leaving a median gap; with short distinct lobiform furculae ( Fig. 1F, K ). Supra-anal plate with a posterior median projection; with two anterior submedian carinae separated by a median furrow; with paired bulges on posterior shoulders ( Fig. 1F, K ). SGP short with obtuse apex. Cercus slender, outer margin straight, inner margin sinuate ( Fig. 1F, K ). Epiphallus ( Fig. 3A, B, G, H ) bridge-shaped; anchorae short and wide, sublateral; lophi wide, lobiform; without inner lophus; oval sclerites well distinct. Flexure distinct.

Female. Penultimate abdominal tergite hind margin excised medially, supra-anal plate with a distinct anterior median furrow. Hind margin tongue-shaped. Valves of ovipositor short, robust, with curved apices; without distinct serrulation ( Fig. 3 E, F, K, L ).

REDEFINITION OF HEBRIDEA

ON THE BASIS OF THE CHARACTERS SHARED

BY THE TWO SPECIES INCLUDED IN THIS GENUS Body cylindrical, elongated. Integument shiny, dorsum of head sparsely pitted, Prn moderately pitted, face wrinkled. Head ( Fig. 1B, D, G, H ) subconical; frons strongly oblique, straight or with a weakly distinct concavity at the upper part of the frontal ridge ( Fig. 1C, H ). Frontal sulcus shallow but distinct above antennae ( Fig. 1B, G ). Fastigium verticis ( Fig. 1B, G ) angulose, almost pyramidal;

distinctly exceeding the antennal scape; without fastigial furrow; with a weakly distinct median carinula vanishing between the eyes; with obsolete lateral carinulae; foveolae absent. Interocular distance usually narrower than the greatest width of the fastigium verticis. Eyes ovoid-hemispherical, more or less prominent. Labrum distinctly notched. Antennae ( Fig. 1A ) filiform, about as long as head and Prn lengths; with about 20 articles, median articles about 3 times as long as wide; antennal distal half articles flattened.

Thorax

Prn cylindrical ( Fig. 1B, G ); anterior margin weakly rounded; posterior margin rounded, neither truncate nor concave; meso- and metasulci well distinct; median carina obsolete in the prozona and metazona; no lateral carinae in adults (present in juveniles); lateral lobes ( Fig. 1C, H ) longer than high; lateral lobes hind margin weakly and regularly concavous; posterovental angle straight; lateral lobes ventral margin angulose, anterior part oblique, posterior part parallel with discus. Episternum ( Fig. 1C, H ) large, sub triangular. Prosternal process ( Fig. 2 ) strong, vertical, transverse, trilobate. Mesosternal interspace ( Fig.2A ) open, narrow, neither rectangular nor trapezoidal; mesosternal lobes rounded, about as long as wide, interspace narrower than a lobe; metasternal interspace ( Fig. 2A ) closed, triangular. Tympanum distinct, large.

Legs

Hind knees about reaching abdomen apex. Hind femur ( Fig. 1D, I ) upper basal lobe longer than lower basal lobe; fishbone pattern distinct; hind femur carinae obtuse, smooth; knee lobes rounded, Brunner’s organ present.Hind tibia distinctly shorter than hind femur; outer apical spine present, nine inner and outer spines (including apical spines). Hind tarsus pilose, about ⅔ of tibial length, arolia very developed.

Wings Brachypterous. FW ( Fig. 1E, J ) reaching the middle of the 3rd abdominal tergite, slightly lanceolate; slightly sclerotised; nervation and reticulation dense. HW about as long as FW; not exceeding FW.

Male

Penultimate abdominal tergite (tergite 10, Fig. 1F, K ) hind margin interrupted medially, leaving a median gap; with more or less distinct short lobiform furculae. Epiproct (tergite 11, supra-anal plate, Fig. 1F, K ) with a posterior median projection; with two anterior submedian carinae separated by a median furrow; with paired bulges on posterior shoulders. SGP short with obtuse apex. Cercus ( Fig. 1F, K ) slender, outer margin straight, inner margin sinuate, narrowing the cercus on the distal third.

Phallic complex ( Fig. 3 A-D, G-J). Epiphallus ( Fig. 3A, B, G, H ) bridge-shaped; anchorae short and wide (dorsal view), of sublateral position; lateral plates anterior ends projecting; lophi wide, lobiform; without inner lophus. Oval sclerites well distinct, oval. Cingulum with horseshoe-shaped apodemal structure; zygoma narrow, weakly sclerotised; latero apical sclerification of ectophallic membrane distinct. Dorsal and ventral valves rounded apically. Flexure distinct.

Female

Penultimate abdominal tergite hind margin excised medially; supra-anal plate with a distinct anterior median furrow. Hind margin tongue-shaped. Valves of ovipositor ( Fig. 3E, F, K, L ) short, robust, with curved apices; without distinct serrulation. SGP longer than wide.

Figures

FIG. 1. — Hebridea Willemse, 1926: A-F, H. rufotibialis Willemse, 1926 male (not a type); G-K, H. amedegnatoae n. sp. male holotype (MNHN-CAELIF595); A, right antenna, dorsal view; B, G, head and pronotum, dorsal view; C, H, head and pronotum left side view; D, I, hind femur right side view;E, J, right forewind;F, K, male supra-anal plate, dorsal view,note the bulge (arrows).Scale bars:1 mm.

FIG. 2. — Hebridea rufotibialis Willemse, 1926 male (not a type): A, sternum in ventral view; B, detail of the prosternal process in frontal view (upside down). Scale bar: 1 mm.

FIG. 3. — Hebridea Willemse, 1926: A-D, G-J, male genitalia: A-F, H. rufotibialis Willemse, 1926 (non type specimens); G-L, H. amedegnatoae n. sp.; A, G, epiphallus,dorsal view;B, H, epiphallus,side view; C, I, phallic complex,right side view;D, J, endophallus,right side view; E, K, female terminalia, left side view; F, L, female terminalia, ventral view. Scale bar: A-D, G-J, 0.2 mm; E, F, K, L, 1 mm.