Taxonomy of the Cixiidae (Hemiptera, Fulgoromorpha) from the Madeira archipelago

Ninety percent of the Cixiidae of the Macaronesian archipelagos are endemic. Each archipelago has its own endemics reaching a total of 31 taxa. The Madeira archipelago comprises fi ve species: Cixius madeirensis China, 1938, C. verticalis Noualhier, 1897, C. chaoensis China, 1938, Hyalesthes madeires Remane & Hoch, 1986 and H. portonoves Remane & Hoch, 1986. Good knowledge concerning taxonomy, habitat information and distribution are essential for the conservation of the biodiversity of this rich archipelago. However, due to intraspecifi c variation and incomplete descriptions, misidentifi cations of Madeira cixiids have been common. In this work, the taxonomy of this family is reviewed and ecological data based on material collected over more than forty years are presented. A new species, Cixius wollastoni sp. nov., is described. A new combination, Tachycixius chaoensis (China, 1938) comb. nov., is proposed, and a new record, Pentastiridius leporinus (Linnaeus, 1761), is reported. Lectotypes are designated for Tachycixius chaoensis and C. verticalis. The genital structures of the latter species are depicted for the fi rst time. All species are diagnosed, described, photographed and illustrated, and an identifi cation key for the family is provided. Thanks to this new information, Madeira together with Tenerife are the two Macaronesian islands with the highest number of endemic species of cixids.

from these is the island of Porto Santo (42 km 2 , the highest point 517 m). Madeira Island is also the highest (1862 m) and the steepest, with 90% of its surface being more than 500 m above sea level. The Desertas Islands include the islet Ilhéu Chão (~1 km 2 , ~80 m the highest point), Deserta Grande (~10 km 2 , the highest point of 479 m) and Bugio (3 km 2 , the highest point of ~411 m). The climate of Madeira is mild with dry and warm summers while Porto Santo is hot and dry (Cropper 2013).
The island of Madeira has the largest number of different habitat types. Around 20% of its surface is occupied by laurel forest -Laurissilva -which is the most signifi cant type of vegetation (Press & Short 1994). The main tree species of this evergreen humid forest are Ocotea foetens (Aiton) Baill., Laurus novocanariensis Rivas Mart., Lousã, Fern.Prieto, E.Días, J.C.Costa & C.Aguiar, Clethra arborea Aiton, Myrica faia Aiton, Persea indica Spreng., and Apollonias barbusana A.Braun (Neves et al. 1996). This pristine forest, recognized as a World Heritage (IUCN 1999), is very rich in endemic plants and animals, particularly insects . The eastern end of this island consists of a long and low peninsula known as Ponta de São Lourenço. This semi-arid area, also rich in endemic species, is the driest part of the island. Here, the vegetation is essentially xerophytic dominated by herbaceous plants, among others Hyparrhenia hirta (L.) Stapf, and halophyte shrubs of Suaeda vera Forssk. ex J.F.Gmel. (Sjögren 1972;Fontinha & Carvalho 1995). The Desertas Islands are a Biogenetic Reserve and are included in the Natura 2000 Network. They also have endemic plants and the vegetation is mainly made up of rupicolous plants, halophytes, grasses (i.e., Holcus lanatus L.) and ferns (i.e., Pteridium aquilinum (L.) Kuhn) (Hampshire 1984;Neves et al. 1992). The island of Porto Santo suffers from desertifi cation and severe erosion caused by intense anthropogenic use (Faust-Lichtenberger 1988). Vegetation is essentially composed of herbaceous xerophilous plants, some of which are endemic (Jardim et al. 1998).
Most of the native forest species of this island have become extinct (Jardim et al. 1998;Carvalho et al. 2013) and replaced by many woody exotic plants (Søndergaard 1995).

Fieldwork
The specimens of this study come mainly from samples targeting the collection of cixiids, but also from regular surveys devoted to the study of insects associated with native and/or introduced plants. The specimens were collected by sweeping with a net over the vegetation on the island of Madeira and the Desertas Islands (Ilhéu Chão and Deserta Grande). No cixids were found in Porto Santo. The swept plants are approximately 90 species, including ferns, grasses, shrubs, and trees, and comprise representatives of endemic, indigenous, and introduced plants. All specimens, except the one from Corredor Verde, were stored dry or in a mixture of 70% alcohol and 2% glycerol and air-dried before being studied. All specimens were pinned and fi xed on small cards and those conserved previously in alcohol were air-dried before being studied.

Diagnosis
Cixius species from Madeira differ from other species of the genus in the structure of the aedeagus: (1) the base of the aedeagus is long and rectangular, with a small midventral expansion and a solid ventral spine at its proximal end; (2) they have two different sized spines distally, one on each side of the theca, the largest one on the right is long and arched upwards or laterally and the other is very small, sometimes almost obsolete; (3) the velum is hump-shaped at the base and narrower and more arched apically.
Externally it is very similar to C. verticalis in colouration and shape, but the vertex is more acute on the anterior margin and strongly curved on the posterior part. It differs from C. madeirensis in the overall colouration, which is darker with larger and darker punctuations on the wings, and the vertex that is acute. Unlike C. verticalis, the lobes of the anal tube in C. wollastoni sp. nov. are not much wider medially than laterally, are less curved than in C. madeirensis and are not as wide. Cixius wollastoni sp. nov. differs from the other Madeira Cixius in the following characters of the aedeagus: (1) the basal half of the vellum is subtrapezoidal with a small dorsolateral denticle; the ventrocranial margin of the distal part is almost straight, not curved; (2) the largest movable spine is slender and curved upward; (3) the medioventral expansion of the basal part of the aedeagus is smaller, gently undulating.

Etymology
The name is derived from Thomas H. Wollaston, in recognition of his contribution to the study of the entomological fauna of Madeira and for collecting of Auchenorrhyncha.   5C). Some males and females have brown stripes on costal margin of tegmina which are more distinctive in females (Fig. 3D). In the holotype the band on the fi rst third is larger, wider and oblique towards the clavus. The other is faint and much shorter, reaching the subcostal vein. Legs yellowish but dark brown around tibiofemoral joints. Abdomen, pygofer and lamella of parameres dark brown. Females darker than males with the setiferous tubercles and markings more distinct; lightest specimens with posterior margins of sternita limited by a thin yellowish strip. Gonoplaca dark brown, lightening towards inner lateral margins.
HEAD. Vertex concave, margin anterior acute and posterior parabola-shaped; medially more than 1.5 times shorter than wide at anterior eye margin (Fig. 4B). Pits between vertex and frons shallow. Forehead convex. Frons more than 1.2 times as wide as long, slightly concave on each side of the medial carina; lateral and medial carina ridged; medial carina tapering along the clypeus (Fig. 4A). Epistomal suture wave-shaped. Medial ocellus vestigial, in some specimens obsolete.
THORAX. Pronotum with three carinae distinctly ridged; medial carina short with a deep pit on each side and two shallow depressions in the post lateral margins. Mesonotum with three sharp carinae of similar size; lateral carinae divergent and obsolete towards the apex (Fig. 4B); posterior margin sharply acute and distal area between the lateral carinae an apex slightly concave. Tegmina 2.75 times as long as wide, extends well beyond the apex of the abdomen; bristles along veins sporadic (Fig. 3D). Metatibia with two small lateromedial spines separated from each other about ⅓ of the length of the tibia; the distance from the fi rst spine to tibiofemoral joints is less than ⅓ of the length of the tibia. First metatarsus with 8 spines distally.
MALE GENITALIA. Pygofer lobes are slightly subtrapezoid, the distal margin almost straight ( Fig. 4F-G, J). Anal tube shallowly concave at the caudoventral margin; lateral lobes asymmetric and slightly bent distally, the widest sub-triangular part medially almost as large as the thinner part ( Fig. 4D-E, H-I).
Parameres dilatated distally, the dorsal margin of the lamella semicircular (Fig. 4C). Ventral margin of the aedeagus with a smooth, wave-shaped projection medially; the proximal margin in the form of a semi-arc, bordered by several small spines, the ventral spine larger and hooked, of variable size ( Fig. 4K-L). The distal end of the aedeagus with a movable spine on each side (Fig. 4L); the right spine, larger and thicker, dorsally directed and slightly curved; the small left spine of variable curvature, sometimes almost obsolete. Velum in repose curved laterally to the right ( Fig. 4M-N); the basal half subtrapezoid with a small dorsolateral denticle; apex of aedeagus narrow and long with ventral margin almost straight and apex hook-shaped ( Fig. 4K-L).
FEMALE GENITALIA. As in C. verticalis. The seventh sternite with caudal margin in the form of an inverted truncated trapeze. Gonoplac ensiform, long and pubescent with longer setae on its dorsal margin. Other characters are non-observable.

Distribution and ecology
Endemic to Madeira Island. It occurs between 300 and 1000 m of altitude in the areas of northern and southern laurel forests. The specimens were collected from May to June in the endemic tree species Clethra arborea and Laurus novocanariensis, as well as in Pteridium aquilinum ferns, and Digitalis purpurea L.

Remarks
Males and females of the Cixius species from Madeira often have three brown stripes on the tegmina, more distinctive on females than males. In some specimens like the holotype, the apical band is often not visible. The band patterns when marked resemble those of C. madeirensis shown in Fig. 3B. There is also a slight variation in the ventral silhouette of the aedeagus and the length and degree of bending of the two spinose processes.
The aedeagus represented by Lindberg (1961: 54, fi g. 4g-i) and erroneously assigned to C. insularis Lindberg, 1954, is very similar to that of C. wollastoni sp. nov. In Lindberg's specimens, the large movable spine is also comparatively small and thin and curves smoothly upwards, does not bend distally as in C. verticalis and C. madeirensis; the apex of the aedeagus is narrow and long with a hook-shaped tip similar also to C. wollastoni sp. nov.; the aedeagal base ends in a long triangular, spine-like process and on its ventral margin there is wave-shaped process similar to that in C. wollastoni sp. nov. The lateral lobes of the anal tube and the lamella of parameres are also like in C. wollastoni sp. nov. But the fl agellum differs; the shape is not subtrapezoidal and is less expanded and the small denticle is missing. However, this part is less chitinous and diffi cult to visualize; therefore it can easily be overlooked. Lindberg did not mention on which specimens his illustrations were based; therefore, it could be from his own collection or from coll. Wollaston, Lundbland or Frey, who provided samples to him.

Diagnosis
Cixius verticalis is the largest of the Madeira Cixius (Table 1). The vertex is sharper on the anterior margin than in C. madeirensis. The overall colouration is darker than in C. madeirensis, with larger and darker wing punctuations. The lobes of the anal tube in C. verticalis do not bend rostrally as in C. madeirensis. The aedeagus differs in the following characters: (1) the basal half of the velum shows a broad, hump-shaped dilatation; (2) the medioventral expansion of the base of the aedeagus is rounded or subtriangular and less pronounced than in C. madeirensis.

Material examined
Lectotype ( Table 1. COLOURATION. Males like C. wollastoni sp. nov. but eyes pale yellow (Figs 3C, 5B), mesonotum glossy; the bands on the tegmina also similar, but vestigial; legs yellowish but the dark brown colour around the tibiofemoral joints extends like a shadow along the tibia. The females are darker than males, as in C. wollastoni sp. nov., and the gonoplacs are light brown, being lighter towards the internal lateral margins ( Fig. 8C-D).
HEAD. Forehead, vertex, and ocellus as in C. wollastoni sp. nov. but differs from this in the vertex that is more excavated, the anterior margin is more angular, and the parabola, on the posterior margin, is less pronounced (Fig. 7B). Frons is approximately 1.1 times as wide as the height medially (Fig. 7A).
MALE GENITALIA. Lateral lobes of the pygofer concave distally ( Fig. 7C-D). The anal tube is as in C. wollastoni sp. nov. but the ventrocaudal margin is slightly concave and divergent, its lobes are subtriangular, and the widest part is distinctly larger medially than at the bas e ( Fig. 7F-H (China, 1938) from Ponta de São Lourenço, 11 May 2001, on Suaeda vera Forssk. ex J.F.Gmel. of paramere oval, the anterior margin is oblique, and the ventral and posterior margins are slightly concave (Fig. 7I). Basal part of the aedeagus long and rectangular with a small rounded or subtriangular ventromedial projection ( Fig. 7K-L); the ventral spine at the proximal end is triangular; there are two thorns subapically; the right-side is large, variable in size, and sharply bends distally at a 90º angle; the left spine is almost straight and sometimes slightly curved, but much smaller and thinner than in C. madeirensis ( Fig. 7M-N). FEMALE GENITALIA. The shape of the caudal margin of the seventh sternite is truncated ( Fig. 8C-D). The anal tube is long and the gonoplac is ensiform and long, reaching the caudal margin of the anal tube, almost touching it from behind ( Fig. 8D). Nineth tergite truncated caudally with caudal margins incurved. The wax secreting fi eld reduced, oval and deeply excavated in the middle but not separated by a distinctive crest; long hairs denser near the lateral margin.

Distribution and ecology
Endemic to the island of Madeira. Due to the successive errors in identifi cation, previous records of this species (Noualhier 1897;China 1938;Lindberg 1941Lindberg , 1961, should be taken with caution. In this study, adults of this species were collected from medium to high altitudes on the slopes of northern Madeira. Adults can be found from April to October in endemic plants that grow in shaded and humid areas of the evergreen laurel forest, such as Persea indica and Clethra arborea trees, Euphorbia mellifera Aiton shrubs and Diplazium caudatum (Cav.) Jermy ferns. It was also found in hedges and trees that grow in the native forest (Lindberg 1961).

Remarks
The type material comprises a male, designated as the lectotype, on which Noualhier (1897) based the original description, and two additional specimens, one female and the other of unknown sex. The last two were used to describe the colour and size of the body. The female is shorter (body length = 7 mm) than all the female specimens of C. verticalis studied (see Table 1); it is more within the range of C. wollastoni sp. nov. However, the vertex, deeply excavated, long, with the anterior margin angular, and the sharp carinae are more like the lectotype of C. verticalis than the holotype of C. wollastoni sp. nov. The body size is larger than in C. madeirensis. The original description of C. verticalis refers that the points along the tegmina veins are not setiferous, but the setae exist although they are diffi cult to recognize and easily breakable.
The identifi cation of C. verticalis has been diffi cult because no credible drawings of its genitalia were available. The original description did not provide any and those published later by Lindberg were wrongly attributed to this species. Lindberg (1941: 27), despite having some doubts, identifi ed specimens from the Azores as C. verticalis. Later (Lindberg 1954: 4-5), based on the same material and new specimens collected by Stora and Frey, he concluded that those of the Azores belonged to different species, which he described as C. (Sciocixius) insularis and C. (Ceratocixius) azoricus. In the same work, he provided the fi rst illustrations of what he thought was the male genitalia of C. verticalis. However, the shape of the aedeagus resembles the genitalia of C. maderensis (Lindberg 1954: 5, fi gs 7-10), particularly the humped projection of the fl agellum and the blunt tip of the apex of the aedeagus. The small spine is also comparatively long and curved. It seems that he wrongly illustrated the specimen(s) of C. madeirensis from the Lundblad collection, which China (1938) had previously studied and identifi ed as C. verticalis. In 1961, he studied these specimens again and new material that he had collected in Madeira. Here he provided new records that he assigned to C. insularis, and, again, what he believed to be the fi rst drawings of the male genitalia of C. verticalis (China 1938: 54, fi g. 4g-i) which are probably C. wollastoni sp. nov. (see above). Since none of Lindberg's drawings seem to correspond to C. verticalis, the genital structures of this species are illustrated here for the fi rst time. China, 1938 Figs 3A-B, 5A, 8A-B, 9A-N Cixius madeirensis China, 1938: 50-51, fi g. 21 (description, illustrations, records).

Diagnosis
This species is easily recognizable by its size, smaller to C. wollastoni sp. nov. and C. verticalis, and brown colouration. It differs from the other Madeira Cixius in the following characters: (1) the basal half of the vellum is hump-shaped but is much narrower on the outer margin than in C. verticalis; the apex is blunt, not scythe-shaped as in C. wollastoni sp. nov. and C. verticalis; (2) the medioventral expansion of the theca is digitiform and more conspicuous and longer. COLOURATION. General light golden brown coloration ( Fig. 3A-B). Vertex light brown, most specimens have two small paler spots that fade to the level of the anterior margin of the eyes (Fig. 9B). Areolar carinae dark brown. Lateral pits on the frons, clypeus, carinae, genae, lora and the 2 nd segment of the antenna, yellowish to light brown, often darker in females. Lateral ocelli glowing yellow. Reddish-brown eyes. Pronotum and tegula as in C. wollastoni sp. nov. Mesonotum brownish-black; lateral carinae, posterior margins and posterolateral margins close to tegula fulvous; in lighter individuals, the area between the lateral carinae is light brown and, in females, it is almost entirely brown. Tegmina yellowish and translucent; pale veins with brown setiferous tubercles; stigma yellowish to dark brown (Figs 3A-B, 5A). Some males and females have three narrow faint brown oblique stripes (Fig. 3B). The band on the fi rst third is larger, wider and bifurcates from the middle, giving rise a short oblique band towards ⅓ of clavus base, and another reaching the clavus lateromedially. The last band forms a dark brown spot below the claval vein fork. The other two strips are short, reaching the subcostal vein. The females are darker than the males and the setiferous tubercles and markings are also more distinctive (Fig. 3A-B); legs, abdomen, and tegmina as in C. wollastoni sp. nov. but, in darker specimens, the brown marks of the tegmina are more intense and extensive.
HEAD. Vertex apex from round to slightly angular (Fig. 9B); posterior margin roundish and about 1.8 times as wide as in the anterior margin of eyes as long. The medial carina of the frons ridged, tapering along clypeus. Epistomal suture wave-shaped, the crest is lower than in C. wollastoni sp. nov. and C. verticalis (Fig. 9A). Medial ocellus reduced or obsolete.
THORAX. Pronotum, mesonotum, tegula, setiferous tubercles along the veins and lateral spines of the metatibiae and the fi rst metatarsus as in C. wollastoni sp. nov., but the tegmina is almost 2 times as long as wide (Fig. 5A).
MALE GENITALIA. Lateral lobes of the pygofer roundish with distal end more or less truncated, similar to a trapezium (Fig. 9F, H). The caudoventral margin of the anal tube concave (Fig. 9G), lateral lobes arc-shaped, wider distally and bent rostrally (Fig. 9J). Lamella of the parameres subtriangular, gradually expanding ventrodistally; proximal margin almost straight and distal margin convex (Fig. 9I). The vellum of aedeagus and basal thorns as in C. verticalis but the smallest spine longer and more curved; expansion of vellum hump-shaped in its basal half; apex blunt. The proximal margin of theca ends in a solid ventral spine like a fi nger of variable size, while the ventromedial projection is large and digitiform ( Fig. 9K-N).
FEMALE GENITALIA. Seventh sternite with truncate inverted caudal margin (Fig. 8B). Gonoplac ensiform and curved upwards; long, about 5 times as long as wide, reaching almost the level of the dorsal margin of the anal tube and exceeding this in half of its length; the dorsal margin pubescent (Fig. 8A). Nineth tergite truncated caudally. Wax secreting fi eld ellipse-shaped and shallowly excavated, approximately 1.5 times as wide as long; not separated medially by a distinctive ridge; scattered long hairs denser near the mediodorsal margin.

Distribution and ecology
Endemic to Madeira Island. Widespread in north and south Madeira; occurs in wet areas of laurel forest between 500 and 1200 m. Adult specimens were collected from April to September preferentially on Clethra arborea trees and on the fern Diplazium caudatum, an endemic species of Macaronesia, and were also found on Pteridium aquilinum ferns and Hydrangea macrophylla (Thunb.) Ser. bushes. This species was reported by Lindberg exclusively from native vegetation (Lindberg 1961).

Remarks
The distal margin of the anal tube, style, and aedeagus are very well shown by China (1938), except that the fl agellum hump is more pronounced than in China's description, possibly because this thin and almost transparent membrane is diffi cult to observe. In contrast, Lindberg's drawings (1954), which he attributed to C. verticalis (see above), show the hump characteristic of the fl agellum and that the ventral process is smoother than in China's illustrations. The blunt apex of the aedeagus, the small curved right lateral spine and the ventral spine-like projection of the proximal margin of the base depicted by China and Lindberg are similar, but the parameres and the anal tube are different.
The values of BL, MW, ML and WL in males and females of C. madeirensis are smaller than in C. verticalis (Table 1) including PW, the only measurement with some degree of overlap (Welch t-test, t (23.98) = 68.24, p < 0.01).

Diagnosis
Tachycixius chaoensis differs from species of the same genus in the form of aedeagus: (1) the velum has a narrow, hump-shaped expansion at the base, and the apical part is arched and thinner than at base; the apex forks into a straight spine-like dorsal projection and a larger scythe-shaped ventral expansion sharply bent to the left; (2) on each side, the basal part of the aedeagus has two small and thin spines strongly curved inward. There are four endemic species of Tachycixius in the Canary Islands grouped in the T. canariensis group (Holzinger 2000). Tachycixius chaoensis differs from them in: (1) the vellum which has a hump-shaped expansion and the apex is bifurcated, not blunt; (2) the movable spines are of similar size and are on each side of the theca, and strongly curved inward; they are also smaller and thinner than in the Canarian species; (3) the medioventral expansion of the theca has a wave-crested shape, and the proximal end is concave and ends in a solid, thin and inwardly curved ventral spine.

Paralectotypes
MADEIRA ISLANDS -Desertas Islands, Ilhéu Chão • 5 ♂♂, 2 ♀♀; "Habitat: Northern Dezerta, (Ilheo Chão)", each labelled "paratype"; NHMUK.  Table 1. COLOURATION. Males overall colouration light brown, females darker (Fig. 3E). Vertex brown with two paler oval spots at the level of anterior margin of eyes; areolar carina dark brown. Frons and medial ocellus yellowish-brown in males and darker in females. Postclypeus yellowish medially with outer margins darker. Anteclypeus brown, slightly lighter medially; in females, the clypeus is darker. Genae, lora and 2 nd antennal segment dark brown. Lateral ocelli golden brown. Eyes blackish brown. Pronotum amber yellow, often light brown medially behind vertex and at posterior angles. Mesonotum brown or dark brown, in some specimens the carinae and posterior margin lighter. Tegula pale brown to light brown. Tegmina translucent, whitish; longitudinal veins pale (Figs 3E, 5F). Some specimens have a darker obliquus strip at ⅓ of the base. Stigma is whitish to dark brown. Wing markings in males reduced and the strips lighter or unnoticeable; legs light brown to brown with varying degrees of shade. Colouration of the abdomen in males and females as in C. madeirensis.

Other material
HEAD. Vertex anteriorly tongue-shaped and concave, and posteriorly trapeze-shaped (Fig. 10B); medially short, about ¾ times as long as wide at the level of anterior eyes margin. Medial carina of the frons smooth, reaching the posterior margin of postclypeus (Fig. 10A). Epistomal suture parabola-shaped, the height of the crest-wave about ⅓ of its width at the base. Lateral pits between the vertex and forehead shallow. Medial ocellus reduced or obsolete.
THORAX. Pronotum and carinae as in C. madeirensis (Fig. 10B). Lateral carinae of mesonotum 2 times more separated distally than basally; length of medial carina about ⅔ of the mesonotum length; the distal area between lateral carinae slightly concave. Tegmina short, narrowing to its distal end; 2.5 times as long as wide in its widest part (Fig. 5F); in females the tegmina are slightly shorter than the abdomen length; bristles along veins sporadic. Metatibia with 3 small lateral spines; 1 st spine located near tibiofemoral joints; the other two spines separated from each other by about ¼ of the tibia length. First metatarsus with 6 spines distally. MALE GENITALIA. Pygofer lobes form an elongated parabola (Fig. 10H). Anal tube asymmetric ventrocaudally, with the caudal margin slightly concave laterally (Fig. 10E); lateral distal lobes thumblike with apex roundish; they bend ventrally with the distal part wider than at the base. Anal style globular, pear-shaped as the cactus fruit (Fig. 10F). Paramere tongue-shaped distally; lamella higher than wide at the base with ventral margin convex and proximal margin slightly oblique (Fig. 10G). Right ventral margin of the aedeagus base with two cranially curved lateroventral spines (Fig. 10J-K); the largest, of variable length, is on the anterior margin, and the thinnest is in the center (Fig. 10J); the anterior margin of the aedeagus base is semi-arched and has a row of small spines, variable in number. The aedeagus base has distally two small hooked spines directed toward each other (Fig. 10J-K). Velum hump-shaped with ventrodistal margin curved inwards; apex bifurcated, the largest portion scythe- shaped, bent sharply to the right; dorsally the shortest spine is directed to the apex of the inferior process ( Fig. 10J-M). FEMALE GENITALIA. Caudal margin of the seventh sternite concave (Fig. 8F). Gonoplac wider distally, about 4.5 times as long as wide, with thin, small scattered setae, mainly on the ventral margin. Gonoplac ensiform, slightly curved upwards up to the dorsal margin of the anal style, touching it behind (Fig. 8E). Lateral margins of the IX tergite distinctly incurved caudally, leaving in the middle a thin channel deeply excavated.

Distribution and habitat
Restricted to the semi-arid coastal habitats, on the peninsula of the extreme eastern end of Madeira Island. It was only known on the rocky table-like islet of the Ilhéu Chão (China 1938;Lindberg 1961). It is probably monophagous on the halophyte Suaeda vera. As in our case, Wollaston collected specimens of this species in May (11 May 1959) (Lindberg 1961).

Remarks
In this study, Cixius chaoensis is transferred to Tachycixius, due mainly by the presence of tubercles on the apical margin between veins; hindwings without the protrusion at the end of Cu2; two lateroventral spines on the left margin of the aedeagus basal-directed and the absence of a medial keel.
The aedeagus is like that represented by China, except for the ventral process of the apex which is more curved to the right, and the distal margin of the parameter which is more rounded. Most of the specimens examined do not show the three wing bands reported by China (1938). China (1938) did not designate a holotype. However, he described both male and female and mentioned: "Habitat: Northern Dezerta, (Ilheo Chão); 6 ♂♂, 2 ♀♀ (WOLLASTON Coll.)". The collection of Wollaston is in the Natural History Museum of London. The curator of Hemiptera of this museum, M.D. Webb, found the 8 specimens of the type series which consist of a male labelled "type" and 7 (5 males and 2 females) each labelled "paratype". The specimen labelled "type" is designated here as lectotype. The specimen was studied by photo (NHMUK).

Diagnosis
The aedeagus of the H. angustulus species group to which H. madeires belongs (Hoch & Remane 1985) have a somewhat simpler confi guration than other species of the genus. The base of the aedeagus is long, rectangular, obliquely crossed by two long spines caudally directed on the left side. H. madeires differs from other species in this group in the following characters: (1) the two long oblique dorsocaudal thorns converge and sometimes cross distally; (2) on the left lateral side, the upper spine is longer than the ventral spine and extends distally over the ventral margin of the aedeagus, while the ventral thorn is more slender than the dorsal. Externally, H. madeires is very similar to H. portonoves but the vertex in males is shorter and the lateral margins are usually divergent, not parallel. The male genitalia of H. madeires differ also from those in H. portonoves in the thickness and curvature of the thorns; the dorsal thorn is wider than the ventral thorn and both converge, the opposite of H. portonoves. COLOURATION. Vertex glowing black; areolar carina pale yellow (Fig. 3F). Triangular shallow pits above frons, genae, lora and clypeus black glowing; marginal carinae of the frons pale yellow; in the widest area, two light yellow to golden brown oval spots at each side of the epistomal suture. Second antennal segment yellow ochre. Carinae of the pronotum pale yellow; posterolateral angles and medial-lateral pits behind vertex dark grey. Mesonotum is glowing black, narrowly brown yellow in the lateral angles behind the tegula and apex. Eyes fulvous; lateral ocelli light yellow to fulvous. Tegula pale yellow. Tegmina hyaline (Fig. 5D); veins yellow ochre with some longitudinal and transverse apical veins, pale brown; the expression of colouration varies. Stigma entirely pale brown and outer margins pale ochre; legs faded brown, lighter on the femorotibial joints, hind tibia yellow, in some specimens with fi ne brown stripes along the lateral grooves. Tarsi of forelegs, middle legs, and apical tarsus of the hindlegs brown. In males, abdominal segments black and genital segments brown ventrally. Pygofer pale to red orange ventrally. In females, abdominal segments black, red orange medially and narrowly pale on the margins.

MADEIRA ISLANDS -
HEAD. Vertex between eyes shorter than in H. portonoves; at the posterior margin approximately 1.7 times as long as than wide (Fig. 11B); lateral margins often divergent posteriorly and apex parabola-shaped; the ridge of the carinae tapering towards the apex. Subtriangular lateral pits between the vertex and forehead shallow. Forehead convex. Length of the frons 1.5 times longer than wide medially (Fig. 11A); lateral carinae ridged, tapering along the distal half of postclypeus; medial carina distinct, of variable length, tapering towards the widest part of the forehead. Frontoclypeus conspicuous. Epistomal suture parabola-shaped but not well delimited. Medial ocellus is vestigial or obsolete.
THORAX. Pronotum with three distinct carinae; medial carina short, delimiting anteriorly two small pits laterally; posterior carinae divergent, forming two shallow depressions in the posterolateral margins (Fig. 11B). Mesonotum with fi ve carinae; the intercostal carinae parenthesis-shaped, from faded to obsolete, do not touch the medial and costal carinae but sometimes reach the anterior margins of mesonotum; costal carinae slightly arched caudally, reaching the anterior margin of pronotum and the posterior margin of mesonotum; medial carina of variable length, almost as long as the costal carinae. Tegula developed. Tegmina extend well beyond abdomen apex, nearly 3 times as long as wide and with sporadic bristles along veins (Fig. 3F). Hind tibia with 1 or 2 small lateral spines, the largest medial and the other, often faded or obsolescent, near the femorotibial joints. The distal end of the fi rst metatarsus with 7 spines.
MALE GENITALIA (see also Hoch & Remane 1985). Pygofer lobes subtrapezoidal, about 3/2 wider ventrally than in the widest median hal f (Fig. 11C, H). The distal part of the anal tube, in lateral view, almost 3 times as wide as the proximal; ventrolateral margin divergent, slightly curved caudally towards the apex and rounded distally. Anal style digitiform, apically slightly globular (Fig. 11F-G). Parameres scythe-like distally, of variable curvature (Fig. 11D); the length of the scythe-like part is half of the paramere length. Aedeagus tubular expanded dorsocaudally in a slightly chitinized projection. Far basally, on the left lateroventral side of the aedeagus base, there is a short, curved thorn of variable size that is caudally directed (Fig. 11I-M). Dorsocaudally from the left side of the aedeagus rise two long oblique thorns directed caudally; these bend strongly to the left side and extend across ¼ of the aedeagus length; they converge and are sometimes crossed distally (Fig. 11K); the dorsal thorn is straight and tapers to the apex; this is longer, wider and thicker than the ventral horn and exceeds it distally as well as the ventral margin of the aedeagus. The ventral thorn is of variable size, being weakly arched medially and distally oblique; the basal half is parallel to the aedeagus base. But there are intraspecifi c differences, particularly in the length and curvature of the aedeagus thorns. These can overlap or not at the terminal end ( Fig.11I-K).

Distribution and ecology
Endemic to Madeira Island. Widespread on the northern and southern slopes, from low altitudes up to 700 m. Occurs in thermophilic coastal areas and ravines where Globularia salicina Lam. grows, but also in areas with continuous water supply. Adult specimens were collected from May to August on two endemic plants, G. salicina and Deschampsia argentea Lowe, and on the widespread Bituminaria bituminosa (L.) C.H.Stirt. It was also found on Echium L., Rubus L. and Euphorbia L. (Hoch & Remane 1985;Remane & Hoch 1986).

Remarks
The Hyalesthes angustulus species group comprises fi ve species (see Hoch & Remane 1985). Two of them are endemic to the Canary Islands, H. fl avipennis and H. teno Remane & Hoch, 1986, and two (Lindberg 1941). Later, in his work on the fauna of Cyprus (Lindberg 1948), he illustrated and compared both species morphologically. He also stated that these two species occurred in the Canary Islands and referred to his previous work (" see Lindberg, 1936"), but did not mention on what material his drawings were based or whether Horváth's material was available to him. In 1961, based on the same material of 1941 and new specimens collected by him, he mentioned that the specimens of H. angustulus from Madeira identifi ed by him in 1941 were H. fl avipennis (Lindberg 1961). Again, he drew what he believed to be the fi rst illustrations of the genitalia of both species (no indication of the origin of the illustrated specimens) (Lindberg 1961: 54, fi g. 4a-f). Although the drawings of 1948 and 1961 are both attributed to the same species, they show substantial differences. Only the one that Lindberg (1961) erroneously attributed to H. fl avipennis resembles H. madeires in the shape of the aedeagus. Hoch & Remane (1985) studied most of Lindberg's material from Madeira and identifi ed all specimens as H. madeires, a new species. Together with this species they described H. portonoves, absent in Lindberg's material.

Diagnosis
This species differs from species of the H. angustulus group of the Canary Islands (Hoch & Remane 1985) in the following characters (1) it has, far basally, on the left lateroventral side of the theca, a short spine, directed caudally, of variable size and thickness, absent in the Canarian species (Fig. 12I-M); (2) on the left ventral side, the long thorns are almost parallel and tips are not divergent. COLOURATION. As in H. madeires (Fig. 3F).

MADEIRA ISLANDS -
HEAD. Vertex, frons, clypeus and medial ocellus as in H. madeires, but the vertex is usually more elongated and the margins are usually parallel (Fig. 12A-B).
THORAX. Pronotum, mesonotum, tegula, tegmina, and legs as in H. madeires (Figs 3F, 5E, 12B). MALE GENITALIA (see also Remane & Hoch 1986). Pygofer, anal tube, anal styles and parameres as in H. madeires (Fig. 12C-H). Body length, position, and curvature of the ventral spine, and the dorsocaudal thorns of the aedeagus as in H. madeires, but the thorns are almost parallel or divergent distally and sometimes the dorsal thorn medially touches the ventral spine ( Fig. 12I-J). The thorns extend along 4/5 of the aedeagus but without overlapping distally. The dorsal thorn is oblique and straight, and is basally directed towards the ventral spine ( Fig. 12I-J). The ventral thorn is thicker and longer than the dorsal; it is approximately 3 times as wide and thick in the middle part than it is at the base, and sometimes the ventral margin is slightly arched in the middle part; in dorsal and ventral view they cross ( Fig. 12K-M).
FEMALE GENITALIA. As shown in Fig. 8G-H.

Distribution and ecology
Endemic to the island of Madeira. It is present from low to medium altitudes within the xerophytic shrub communities of the south of the island both in the coastal regions and in the gorges. Adults occur from April to August on Globularia salicina and Suaeda vera, but they have also been collected from Echium and Euphorbia species (Hoch & Remane 1985;Remane & Hoch 1986). It seems to prefer more exposed areas than H. madeires.

Remarks
There are intraspecifi c differences in the male genitalia. The ventral spine can vary in length, thickness, and curvature ( Fig. 12I-J).

Diagnosis
It differs from other European species of the genus in the following characters: (1) the apex of the velum ends in two processes, a ventral tongue-shaped expansion and, exceeding it, a thin, spine-like extension curved downward; (2) on the right, laterobasal to the base of the aedeagus, is a long, thin spine that extends around the theca and almost embraces it; this thorn is slender and the distal third is bent at a right angle.
COLOURATION. Vertex with a medial rectangular blackish spot; lateral sides of the vertex, pronotum and the areolar and frontal carinal areas, pale yellow; frons, clypeus, gena, and lora black in males, golden brown in females. Mesonotum and femora black in males and lighter in females. Female tegmina milky white, semitransparent; veins and stigmas of pale golden colour, in males they are darker.
HEAD. Vertex almost as long as wide in the posterior margin (Fig. 13A). Epistomal suture pronounced in a wave form.
THORAX. Mesonotum with fi ve distinctly ridged carinae; the costal carinae are slightly divergent and reach almost the posterior margin of the mesonotum, being shorter than the medial and intercostal carinae; these two end up subapically at the caudal margin of the mesonotum; the intercostal carinae are shaped as a pair of parentheses and at the base are shorter than the medial and costal carinae (Fig. 13A). MALE GENITALIA (see also Holzinger et al. 2003). Pygofer lobes concave distally (Fig. 13C). The anal tube is oblong dorsally and distally blunt; at the base it is 2 times shorter than caudallly (Fig. 13F); lateroventral margins widely concave (Fig. 13G). Parameres 2.5 times as long as wide in the widest part; caudally there is a large rounded subtriangular area that narrows basally towards the outer margin; inner lateral margin slightly concave and outer margin straight (Fig. 13B). The aedeagus base forms dorsolaterally an almost fl at pentagonal plate; from the middle to the distal end of the plate rises dorsolaterally a caudally directed process. Velum is arch-shaped and narrows towards the apex; distally and dorsoventrally, the apex ends in a tongue-shaped process, and dorsally, exceeding this, there is a thin spine that curves down. On the right, laterobasal at the base of the aedeagus, there is a long and thin spine that extends parallel almost embracing it distally; this thorn narrows towards the apex and the distal third bends upward in the form of a sickle (Fig. 13E). Dorsally, at the base of the velum, there is a small spine-like process and from here three movable spines are raised, one long and thick and two small and thin; the longest extends parallel to the dorsal margin of the fl agellum and reaches approximately half of its length; the shortest spine is almost parallel to the base of the fl agellum and bends slightly medially downwards; the last spine is oblique to the velum (Fig. 13D). FEMALE GENITALIA. Not described.

Distribution and habitat
The Palearctic region, except in the northern parts. In Madeira, this species is found in Phragmites australis Trin. ex Steud. in the only tide lagoon of the island, which is located on the southern coast.

Remarks
The curvature of the long lateroventral spine of the aedeagus is variable at its distal end as is shown in Wagner (1970: fi g. 3c).

Key of Madeiran Cixiidae based on males
4. Body length > 7.20 mm. Vertex slightly acute at the anterior margin and concave at posterior margin (Fig. 7B); ventral margin of the aedeagus with a fi nger-shaped expansion; the largest lateral thorn curves distally forming an angle of 90º; vellum gibbous, without dorsal denticle and the ventral margin distinctively curved distally (Fig. 7K-N)  Vertex distinctly acute at the anterior margin and tongue-shaped at the posterior margin (Fig. 4B); ventral margin of the aedeagus with a wave-shaped expansion; the larger lateral thorn is curved and does not form a 90º angle distally; vellum subtrapezoid, with a small dorsal denticle and the ventral margin almost straight distally (Fig. 4K-N) ....C. wollastoni sp. nov.
5. Body length > 5 mm; fi rst metatarsus with more than 10 spines. Aedeagus with a long, hook-shaped thorn along the right lateral side and 3 smaller thorns distally on the left side of the aedeagus, two of them much longer (Fig. 13D-E) Remane & Hoch, 1986

Discussion
The Cixius species of Madeira are morphologically very similar but, in terms of genital structures, they form a different group from those of the Azores and the Canary Islands. The Madeiran Cixius species are separated from the species of the Cixius insularis and the Cixius azoricus groups of the Azores in the position, number and size of the thorns and the shape of the velum. The species of the Azores, instead of two, have three large thorns, one on the left side and two on the right side of the aedeagus, of equal (C. insularis group) or unequal size (C. azoricus group) (Remane & Asche 1979;Hoch 1991). The most similar species to those of Madeira is C. palmensis Lindberg, 1960 of the Canary Islands, but the size and curvature of the spines of the aedeagus are different and the velum expands further at the base, while the apex is sharp, not rounded (Hoch & Asche 1993).
The assignment of the species of Madeira to one of the described subgenera of Cixius is problematic. Wagner (1939) recognized 10 subgenera of Cixius, based on the form of aedeagus. Another Mediterranean subgenus was described by Ribaut (1960), and some subgenera were synonymised by Holzinger et al. (2003). Lindberg (1954: 4) suggested that C. verticalis (probably actually C. madeirensis) should be placed close to the subgenus Ceratocixius Wagner, 1939. The Madeira species have two movable thorns, as in the species of the subgenus Ceratocixius. However, the thorns are distinctively unequal and the bending direction is different; the ventral process of the aedeagus is not a pronounced crest but a smaller fi nger-shaped process, and the fl agellum has a hump-shaped expansion which is absent in Ceratocixius spp. Lindberg (1960: 15) also suggested that C. palmensis is more closely related to the species of the subgenera Paracixius Wagner, 1939 and Ceratocixius. The phylogenetic signifi cance of the differences in these aedeagal structures remains to be clarifi ed; thus, a reliable assignment to the weakly defi ned subgenera of Cixius can only be made after a phylogenetic analysis of the genus.
The confi guration of the male genitalia in Tachycixius chaoensis is also different from that of the species of the Canary Islands. The phylogeny of the genus Tachycixius is unknown. Presently, the genus comprises 26 species, including T. chaoensis, grouped according with the shape of genital structures, in fi ve species-groups (Holzinger 2000;Holzinger et al. 2002). The T. canariensis group comprises all the species of the Canary Islands. Tachycixius chaoensis differs from the species of this group in the presence of a small movable spine on each side of the aedeagus instead of two large thorns on the right side. In addition, the apex of the fl agellum is bifi d and not blunt, and the theca has ventrally a rigid spine, absent in the canariensis group. Like T. chaoensis, Cixius (Ceratocixius) suaedicola Remane & Holzinger, 1998, from southwest Morocco, is associated with the halophyte Suaeda Forssk. ex J.F.Gmel. However, the aedeagus confi guration is different. In T. chaoensis, the ventral margin of the aedeagus does not have a large keel, the movable spines are much smaller, the apex of the vellum ends in two instead of one spine and has no arch form but a hump. The conformation of the thorns in T. chaoensis is more like species of the pilosus group (i.e., T. arzonei Holzinger, 2000 andT. remanei D'Urso, 1999). It shares with these a ventral rigid spine and a movable spine on each side of the aedeagus. But the movable spines in T. chaoensis are of similar size, much smaller and strongly curved upwards. The length of the forewings and the size of the body of males and females of T. chaoensis is also smaller than the species of the T. pilosus group (see Holzinger 2000Holzinger : 1271. Females differ also. In T. pilosus, tergite IX rises perpendicular to the body axis, and the ovipositor curves dorsally, a confi guration considered apomorphic in some cixiids (see Holzinger et al. 2002). In T. chaoensis tergite IX narrows towards the anal segment and the ovipositor curves dorsally, reaching the genital segment, a pattern considered plesiomorphic. The phylogenetic relationships between the species of the different groups are unknown and the monophyly of the genus questioned (Holzinger et al. 2002).
The phylogenetic analysis of the species of the genus Hyalesthes conducted by Hoch & Remane (1985) includes the species of Hyalesthes of Madeira in the monophyletic group of H. angustulus. In addition to H. angustulus, present on the Canary Islands and in North Africa, this group contains two endemic species of the Canary Islands: H. fl avipennis Horváth, 1909 and H. teno Remane & Hoch, 1986. The apomorphies of the H. angustulus group are three: the folded section of the aedeagus is shortened and moves to the left side, the distal basal thorn (at least partially) is integrated into the membranous area of the distal part of the aedeagus, and the anteclypeus and postclypeus are smooth, without medial decay (ibid.). Madeira species share with the angustulus group two large thorns directed caudally on the left side of the aedeagus, of which at least one bends obliquely to the aedeagus base. But it differs from them in the presence of a small medioventral spine near the base of the aedeagus and the size and curvature of the thorns also differ.
The Azores, Madeira, and the Canary Islands are the only Macaronesian archipelagoes with endemic species of Cixiidae. Some lineages of the genus Cixius, Tachycixius and Hyalesthes gave rise to endemic species in the Canary Islands and Madeira, while in the Azores all endemic species belong to the genus Cixius. Some Tachycixius and Cixius have evolutionarily adapted to life in caves (Remane & Hoch 1988;Hoch 1991;Hoch & Asche 1993). Of the 10 troglobitic species known, two (Cixius spp.) occur in the Azores and eight (Cixius, 6 spp; Tachycixus, 2 spp.) in the Canary Islands. In Madeira, the cave fauna of the Cavalum lavatubes (Madeira Island) was studied over a year by Élvio Nunes and Aguín-Pombo, but no troglobitic species were found. Despite this, the number of endemic species of the island of Madeira is remarkably large. It is the same as Tenerife (Oromí et al. 2004), an island which is almost three times larger, twice as high and ecologically more diverse in habitats (Fernández-Palacios et al. 2004). In oceanic archipelagoes such as Madeira, which have never been joined to the continent, the number of islands, the area, the age, the distance to the mainland and the habitat diversity play key roles in colonization and species differentiation. Oceanic islands are rich in biodiversity, particularly concerning endemic species, but also have much higher extinction rates (Frankham 1997(Frankham , 1998. Endemic species with restricted distribution, such as T. chaoensis, and possibly also C. wollastoni sp. nov., deserve special attention during the designation and management of protected areas.