Ambarcader eugenei, Perrichot, Vincent, Nel, André, Guilbert, Éric & Didier, 2006

Perrichot, Vincent, Nel, André, Guilbert, Éric & Didier, 2006, Fossil Tingoidea (Heteroptera: Cimicomorpha) from French Cretaceous amber, including Tingidae and a new family, Ebboidae, Zootaxa 1203, pp. 57-68 : 59-62

Ambarcader eugenei , sp. nov.

( Fig 1 )

Type. Holotype male specimen MNHN Cdl 2.28, housed in the Laboratoire de Paléontologie, Muséum National d’Histoire Naturelle, Paris, France.

Locality. Cadeuil, Charente­Maritime, France.

Stratigraphic horizon. Lower Cretaceous, Lowermost Cenomanian (Néraudeau et al. submitted).

Etymology. Dedicated to Mr Eugène Arnaud who provided the type specimen.

Diagnosis. As for the genus.

Description. Head extending far in front of compound eyes; eyes fully developed; antennae four­segmented, with third segment the longest and last segment clubbed; no visible ocelli; rostrum reaching the third abdominal segment; bucculae not visible, hidden under prothoracic femur; six long, porrect spines, one dorso­medial between eyes, two frontal, one clypeal, and two jugal.

Thorax. Collar well­defined, separated from pronotal disc by a transverse furrow, anterior margin somewhat tectiform and produced in front by a double process; pronotal disc transverse and swollen, with broad areolae and three longitudinal carinae, one long median, unseriate ending anteriorly at calli, and two very short lateral, with median one the highest, just behind calli; scutellum triangular and nearly completely hidden under pronotum, covered with small punctuations; paranota very broad, three­lobed, extending anteriorly to level of hind margin of eyes, with 5–7 rows of wide areolae; metapleural ostiolar canal nearly straight, non­branching and nearly vertical.

Hemelytra. Completely developed, covered by large­rounded areolae, the largest being rather regular; clavus large, separated from mesocorium by a clear commissure; presence of a faint vein ACu on corium along clavus; costal area very broad, showing 4–5 rows of areolae not separated into smaller groups by a web of strong veins; subcostal area narrower, separated by six distinct transverse veinlets; vein RM sharply raised; discoidal area slightly broader than subcostal area, with 5–6 rows of areolae, subdivided into three smaller groups by two strong transverse veins; sutural area with six rows of areolae of same structure than costal area; stenocostal area absent; hypocostal vein very high, subcostal and discoidal areas higher than costal area. Hind wings not visible.

Legs. Long and slender, fore, mid, and hind legs of equal length; trochanters not fused with femora; tarsi two­segmented.

Abdomen. Only second and third sternites fused (‘visible abdominal segments I and II fused’, sensu Froeschner 1996), ‘separation’ between them being distinctly less indicated than between other sternites; tergites and paratergites not visible (sensu Péricart 1983); genitalia poorly visible.

Measurements (in mm): length of body 3.15 (from head to wing apex); length of head 0.63; length of antennal segment I and II 0.13, III 1.13, IV 0.28; length of rostrum 1.75; length of head spines 0.25; length/width of pronotal collar 0.16/0.48; length/width of pronotal disc 0.48/0.88; width of paranota 0.38; length/width of hemelytra 2.13/0.75; length/width of clavus 0.88/0.25; width of costal/subcostal/discoidal/sutural areas 0.25/ 0.19/0.25/0.2; length of femur/tibia/tarsi 0.75/0.9/ 0.14 in fore, mid and hind legs; length/ width of abdomen 1.13/0.9.

Discussion. The new genus Ambarcader is clearly a Cantacaderinae (sensu Drake & Ruhoff 1965; Froeschner 1996) because of its well­developed and visible clavus, and abdominal segments I and II visible and fused. It is also clearly a Phatnomatini (sensu Froeschner 1996) by the lack of a stenocostal area, as well as the characteristic dorsomedial and clypeal spines. Note that Golub (2001) indicated that ‘a well developed clavus is characteristic not only of the Cantacaderini and Phatnomatini, but also of many Tinginae’.

In two partial phylogenetic analyses, Lis (1999) characterized the ‘Cantacaderidae’ by the following synapomorphies: (1) ‘stenocostal area present’ (see Froeschner 1968 for definition). This character is always absent in the ‘Tingidae’ (sensu Lis 1999). Guilbert (2001) indicated that the ‘presence of a stenocostal area’ is an autapomorphy of the Cantacaderini. Golub and Popov (1998, 1999) noted that the Cantacaderini have ‘a complex ostiolar­stenocostal system’, i.e., ‘separation of stenocostal area […] by veins C and Sc’, unlike the Phatnomatini; (2) ‘trochanter fused with femora’; (3) ‘peritreme of scent gland crevice­like’; (4) ‘lateral carinae of collar present’; (5) ‘gonoplacs membranaceous’; (6) ‘pseudospermatheca absent’. In the new genus Ambarcader , character states (1) and (2) are absent, (3) cannot be accurately observed and (5) and (6) are not visible. Thus, Ambarcader has none of the potential synapomorphies of the ‘Cantacaderidae’ sensu Lis (1999).

Golub (2001) proposed, in a non­phylogenetic analysis, one ‘synapomorphy’ for the Cantacaderinae (= Cantacaderini + Phatnomatini), i.e., ‘presence of several or many additional elevating cross veins on the hemelytra’. This character seems to be present in Ambarcader , although its cross­veins look differently organized compared to Cantacader ; but the polarity and value of this character have not been tested by a phylogenetic analysis. Golub (2001) also contradicted the polarity of the character state ‘a visible clavus’ proposed by Guilbert (2001), indicating that this character is plesiomorphic, but without supporting this assumption by a phylogenetic analysis. According to Drake and Ruhoff (1965) and Froeschner (1996), Ambarcader would fall into the Phatnomatini owing to the absence of the stenocostal area. According to Lis (1999) and Golub (2001), the unique synapomorphy of the Phatnomatini would be the presence of the clypeal spine, as shown by Ambarcader . Thus it is most probably related to this group.

Froeschner (1996) proposed a key of the modern genera of Cantacaderini and Phatnomatini. No Cantacaderini have a pattern of head spines similar to that of Ambarcader . The modern genera Exulmus, Indocader , and Phatnomella have very broad and lobed paranota and a pattern of head spines similar to that of Ambarcader . But none of these genera has an anterior margin of pronotum similar to that of Ambarcader , with its double curve and a median indentation. The recent genus Afghanoderus Lis has large paranota but with a strong anterior angle only and a different pattern of head spines ( Lis 2001). The two species of Paraphatnomella Lis have broad rounded paranota that extend to the level of the eyes, but with a small anterior lobe, unlike in Ambarcader . Furthermore, they have a costal area with 2–3 rows of areolae, narrower than the discoidal area ( Lis 2000), unlike Ambarcader . The Argentinian genus Pampacader Carpintero & Montemayor differs from Ambarcader in having seven head spines, a concave anterior pronotal margin, and sinuate paranota margins ( Carpintero & Montemayor 2005).

The fossil genus Intercader Golub & Popov (Upper Eocene Baltic amber) has rounded paranota. Tingicader Golub & Popov (Upper Eocene Baltic amber) differs from Ambarcader in its numerous spines on the lateral margins of the pronotum and hemelytra ( Golub & Popov 1998). The genus Eocader Golub & Popov (Oligo­Miocene Dominican amber) has paranota distinctly less expanded than those of Ambarcader , with only one row of areolae in its posterior half ( Golub & Popov 2000b). Exmeselensis Wappler (Middle Eocene, Germany) has very narrow paranota ( Wappler 2003).

Figures

FIGURE 1. Ambarcader eugenei new genus and species, in Cenomanian French amber. Holotype MNHN Cdl 2.28. A. General habitus in dorsal view; B. General habitus in ventral view; C. Detail of head and pronotum; D. Detail of hemelytra.