Lamaxa, Bartlett & Kennedy, 2018

Bartlett, Charles R. & Kennedy, Ashley C., 2018, A review of New World Malaxa (Hemiptera: Fulgoroidea: Delphacidae), Zootaxa 4441 (3), pp. 511-528 : 516-517

Lamaxa , new genus

( Figures 7–18 , 25–26 , 36 , 38, 40–42 )

Type species. Malaxa occidentalis Muir, 1926 .

Description. Color. Brownish-orange with brown and paler markings; wings clear with characteristic dark (and sometimes pale) markings. Structure. Body slender and elongate; length (from apex of vertex to tip of tegmina) males x ‾ = 4.97 mm (4.71–5.33 mm, n=5); females x ‾ = 5.31 mm (5.10–5.62 mm, n=6). Head much narrower than pronotum ( Figs. 7, 10 ), carinae concolorous. Lateral carinae of clypeus, frons (~metope) and vertex (~coryphe) distinct, other carinae obscure, especially near fastigium. Frons elongate and parallel-sided, widest near frontoclypeal suture, narrowed to fastigium ( Figs. 9, 12 ; l:w x ‾ = 2.6:1). Vertex longer than broad at base (l:w x ‾ = 1.4:1), distally narrowing and projected slightly in front of eyes; submedian carinae uniting before fastigium, basal compartments longer than wide. Rostrum reaching or exceeding metathoracic trochanters. Antennae cylindrical, both segments very long ( Figs. 10, 12 ), surpassing apex of clypeus (and apex of mesonotum), segment I close to half length of II (ratio I:II 0.4–0.5:1), length antennal segment I x ‾ = 0.47 mm, II  = 1.05 mm. Pronotum shorter than vertex in middle line, lateral carinae usually not attaining hind margin. Mesonotum longer in middle line than vertex and pronotum together. Wings elongate, much longer than abdomen, nodus at about 2/3 length, apex acutely rounded ( Fig. 36 ). Spinal formula of hind leg 5-7-5 (or 5-6-5). Calcar thick, concave on inner surface, without teeth along the hind margin, with an apical tooth. Pygofer irregularly quadrilateral in lateral view ( Fig. 26 ). In caudal view, opening carinate, with midventral forked process ( Figs. 13 , 25 ), broad lamellate medioventral processes absent. Dorsocaudal margins of pygofer expanded and inflected to partially enclose anal tube ( Fig. 42 ), diaphragm evident, armature absent. Gonostyli broad basally, basal angles prominent, diverging and narrowed distally to apically to blunt or acute apex ( Figs. 25 , 40 ). Aedeagus elongate and tubular with large, flattened, poorly sclerotized subapical process ( Figs. 14 , 38 ; representing a flagellum?). Anal tube (anal segment) small, without processes.

Remarks. Lamaxa differs from Malaxa acutipennis in having a parallel-sided wing with a rounded apex (vs. pointed with an arched leading wing edge in Malaxa acutipennis ); antennae are similar in proportion but nearly twice as long in Lamaxa than Malaxa acutipennis (and lacking the ventral carina on I); the genitalia of Lamaxa bear a forked projection on the pygofer opening, whereas Malaxa acutipennis is simple; and the dorsocaudal margin of the pygofer is expanded in Lamaxa but not in Malaxa . The aedeagus of Lamaxa is slightly curved and caudally directed, bearing weakly sclerotized apical projections (vs. downcurved in Malaxa acutipennis ).

Lamaxa differs from the Chinese Malaxa in structural proportions along with distinctive features of the male genitalia. Lamaxa is larger than the Chinese Malaxa , the vertex is more elongate, the lateral carinae of the pronotum are laterally curved, usually not reaching the hind margin, and the spinulation of the hind leg is 5-7-5 (or 5-6-5) (instead of 5-6-4). More distinctly, in Lamaxa , the anal tube is without processes, whereas in Chinese Malaxa , the anal tube bears a single (sometimes 2), large usually strongly asymmetrical process(es). In Lamaxa , the dorsocaudal angle of the pygofer is projected (simple in Chinese Malaxa ), and the midventral portion of the pygofer opening bears a forked process, whereas in Chinese Malaxa , there are “two broad lamellate medioventral processes, between of them with a V-like emargination” ( Hou et al. 2013: 867), although these are reduced in some species. In Chinese Malaxa , the aedeagus is downcurved and C-shaped, whereas in Lamaxa the aedeagus is slightly curved and caudally directed, bearing weakly sclerotized apical projections, missing from Chinese Malaxa .

Species included are Lamaxa gracilis ( Fennah, 1945) and Lamaxa occidentalis ( Muir, 1926) . Two female specimens, probably representing additional species of Lamaxa were examined (listed below under ‘females tentatively assigned to Lamaxa ’). One was a specimen from Honduras that was similar to the coloration of Lamaxa occidentalis , except that the face (frons, genae, clypeus) were broadly black except for a strongly contrasting pale stripe above the frontoclypeal suture, also bearing more substantially embrowned wings. The second, from southern Brazil, was very pale yellowish with weakly marked wings, a dark longitudinal line along both segments of the antennae, and partially embrowned legs.

Etymology. The new genus name “ Lamaxa ” is an anagram of “ Malaxa ”, and is to be understood as feminine in gender.

Figures

FIGURES 7–14. Lamaxa occidentalis (7–9, 13–14 paratype male, Napo River, Ecuador; 10–12 La Selva Biological Station Costa Rica); 7, habitus dorsal view; 8, habitus lateral view; 9, frontal view; 10 habitus dorsal view; 11, habitus lateral view; 12, frontal view; 13, pygofer, caudal view (embedded in balsam); 14, aedeagus, connectives, gonostyli and anal tube, left lateral view (embedded in balsam).

FIGURES 15–18. Lamaxa gracilis (holotype); 15, habitus, dorsal view; 16, habitus, lateral view; 17 frontal view; 18, labels.

FIGURES 25–29. Male genitalia of Lamaxa occidentalis (25–26) and Xalama microstyla (27–29); 25, pygofer, semiventral view (note shape of process on ventral margin of pygofer opening); 26, pygofer, left lateral view; 27, pygofer, left lateral view; 28 pygofer, near caudal view; 29, pygofer, ventral view (note shape of process on ventral margin of pygofer opening).

FIGURES 35–37. Forewing, line art, leading margin ventrad; 35, Malaxa acutipennis; 36, Lamaxa occidentalis; 37, Xalama microstyla.

FIGURES 38–42. Redrawn line art; 38, Lamaxa occidentalis, aedeagal complex (aedeagus, connective, gonostyli) and anal tube from Muir 1926 (figure 6); 39 Malaxa microstyla, lateral view of terminalia, from Muir 1930 (figure 7); 40, Lamaxa gracilis, caudal view of pygofer (Fennah 1945, figure 94); 41, Lamaxa gracilis, median process of pygofer, ventral view (Fennah 1945, figure 91); 42, Lamaxa gracilis, anal segment and expanded dorsocaudal portion of male pygofer, posterodorsal view (Fennah 1945, figure 93).