Xalama, 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 : 520

Xalama , new genus

( Figures 19–24 , 27–29 , 37 , 39 )

Type species. Malaxa microstyla Muir, 1930: 211

Description. Color. Brownish with distinctive paler markings, especially on head; wings clear with strong fuscous markings ( Figs. 19–21, 23–24 ). Structure. Body slender and elongate; length males  = 4.69 mm (n=5); females not available (only males examined). Head narrower than pronotum ( Figs. 19, 23 ), carinae concolorous. Carinae of head distinct although median carina of vertex weaker. Frons elongate and parallel-sided, narrowed between eyes, widest near frontoclypeal suture ( Figs. 20, 24 ; l:w  = 2.5:1, n=5). Vertex narrowing distally, slightly projecting in front of eyes, vertex broader along hind margin than along midline; submedian carinae distinct, uniting before fastigium, basal compartments longer than wide. Rostrum reaching hind coxae. Antennae cylindrical, segment II long; nearly surpassing apex of clypeus; segment I about 1/3 length of II ( Figs. 20, 24 ; ratio I:II 0.37:1), length antennal segment I  = 0.13 mm (n=5), II  = 0.34 (n=5). Pronotum subequal or just shorter than vertex along midline, lateral carinae usually not attaining hind margin. Mesonotum longer in middle line than vertex and pronotum together. Wings elongate ( = 3.8 mm, n=5), much longer than abdomen, predominately clear with distinctive dark markings, nodus at about 2/3 length, wing apex rounded. Spinal formula of hind leg usually 5- 6-4. Calcar thick, concave on inner surface, without teeth along the hind margin, bearing an apical tooth. Pygofer roughly triangular in lateral view ( Figs. 27 , 39 ), elongate ventrally and strongly narrowed dorsally; pygofer opening and lateral margins with projections (in microstyla , midventral projection is a broad, rounded scoop in caudal view, lateral projections just below midlength in form of rounded tooth in lateral view); diaphragm from lateral projections of pygofer broadly concave beneath gonostyli (weak or absent above gonostyli). Gonostyli ( Figs. 27, 28 ) flattened and curled (apically scoop-like), irregularly parallel-sided, curved medially; bearing low, rounded tooth medially near midlength; apically broader and more flattened, somewhat angular, bearing find, irregular serrulations on inner apical margin fine, irregularly placed setae. Aedeagus ( Figs. 27 , 39 ) elongate and robust, strongly downcurved into long, sclerotized structure, slightly twisted, bearing an irregular row of teeth on left and right sides and long, downward projecting process at curve. Anal tube (anal segment) small and simple.

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

Remarks. The new genus is similar to Malaxa acutipennis in having a simple anal tube and a strongly downcurved aedeagus; also, the gonostyli may be considered grossly similar in appearance. They differ in that Xalama has projections (lateral and midventral) on the opening of the pygofer (vs. simple), the proportions of the antennae, and the shape of the wings and details of the wing venation.

Xalama differs from the Chinese Malaxa in having a simple anal tube, and the projections on the opening of the pygofer is different; also, although it is not entirely clear from all the illustrations of Chinese Malaxa , it appears that the diaphragm is much more complete in Malaxa than in Xalama . Also, Xalama has much shorter antennae which are differently proportioned between the two segments.

Xalama differs most obviously from Lamaxa in the nature and proportions of the antennae (much shorter in Xalama ), and in the downcurved aedeagus (versus caudally-projecting with apical membranous flagella), and the nature of the processes on the opening of the pygofer.

Figures

FIGURES 19–24. Xalama microstyla (19–22 holotype; 23–24 Peru); 19, habitus, dorsal view; 20, frontal view; 21, habitus lateral view; 22, labels; 23, habitus, dorsal view; 24, frontal view.

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).