First record of the genus Acridurus Perez, Dominici, Hierro and Otte, 1995 from Cuba, with description of a new species (Orthoptera: Acrididae: Ommatolampidinae)

The genus Acridurus Perez, Dominici, Hierro & Otte, 1995 is herein recorded for the first time from Cuba, based on a new species. Acridurus baracoae n. sp. is described on the basis of four specimens from three separate localities enclaved in the northeastern mountains of the main island (Holguín and Guantánamo Provinces). The description herein presented is supported by a thorough illustrative complement, which includes a precise map and color photographs of habitus, main morphological diagnostic characters and habitat.


Introduction
The genus Acridurus Perez, Dominici, Hierro & Otte, 1995 (Acrididae: Ommatolampidinae) was so far known to occur only in the Greater Antillean island of Hispaniola, more specifically in southern Dominican Republic Perez-Gelabert, 2008), containing only three poorly diagnosed species: Acridurus robustus Perez, Dominici, Hierro & Otte, 1995, Acridurus yayitas Perez, Dominici, Hierro & Otte, 1995 and Acridurus neibanus Perez, Dominici, Hierro & Otte, 1995. The apparent absence of Acridurus from Cuba has been always intriguing, but otherwise not problematic in view of the very poor and fragmented knowledge of the orthopterofauna of this Greater Antillean island. Recently, Yong & Perez-Gelabert (2014) recorded 15 nominal species of Acrididae from Cuba (six of them national endemics) and recorded for the first time the subfamily Ommatolampidinae Brunner von Wattenwyl, 1893, based on three "unknown genera".
One of these genera was based upon a single female and declared by Yong & Perez-Gelabert (2014) as "Genus unknown 2" [sic]. It was also stated in that paper: "The robustness and morphological features of this specimen [...] suggest some similarity to the Hispaniolan genus Acridurus" (Yong & Perez-Gelabert, 2014: 412).
Very recently, the present author was fortunate to obtain three additional adult females of this grasshopper, all of them in perfect state of preservation and with reliable collecting data. The detailed study of this sample demonstrated that it indeed represents the first Cuban member of Acridurus. The new species is herein described and thoroughly illustrated; subsequently also the generic diagnosis is emended to accommodate its new member and to correct a few original inconsistencies of Perez et al. (1995).

Material and Methods
The specimens were studied, measured and photographed under a Zeiss Stemi 2000-C stereomicroscope, equipped with line scale and grid ocular micrometers, and a Canon PowerShot A620 digital camera. The digital images were processed with Adobe Photoshop CS3 only slightly, i.e., optimization of bright and contrast parameters, background removal and plate composition.
Specimen labels are laser-printed in Spanish, but all were transcribed here into English for text coherence purposes. Precise coordinates and altitude of each locality were extracted from updated 1:25 000 military topographic maps in Mapinfo 9.0.
The general terminology follows Fontana et al., 2008 andAguirre-Segura &Barranco Vega (2015); such diversity of sources is currently unavoidable because none of them covers by itself alone the whole range of structures and terms. Taxonomic arrangements were also verified using the Orthoptera Species File Online (OSF), version 5.0/5.0 (Cigliano et al., 2016). All  Etymology. The specific epithet is an eponym derived from Baracoa, the main section of the orographic system, which encloses all known localities of the species (the Sagua-Baracoa Mountains).
Description (adult female holotype). Size large for the genus (total length 30.65 mm). General coloration reddish brown, without any sharply contrasting patterns, eyes black. See figure 1 and table I.   Head (figs. 2a-c). Large, exactly as long as wide. Tegument shiny but sparsely and coarsely punctate, essentially glabrous. Vertex moderately convex in lateral view, subtriangular in dorsal view; fastigium prominent, paraboloid in dorsal view, semicircular in lateral view and strongly compressed in frontal view. Eyes large, suboval and prominent; ocelli minute. Genae moderately convex in frontal view. Antennae standard for Acrididae in size and shape, with 21/21 flagellomeres; scapus subcylindrical, depressed, longer than wide (ratio = 1.5), oval in cross-section, essentially glabrous; pedicel about half the length of scapus.
Abdomen. Large and slender (conspicuously narrower than pronotum), subcylindrical and evenly tapering posteriorly. Tegument smooth and shiny, with small scattered setae. Tympanic organ oval-elongate, located laterally on segment I. Supra-anal plate ( fig. 3c) longer than wide (ratio = 1.2), paraboloid, sparsely setose. Cerci very short, conical and densely covered by thin setae. Subgenital plate ( fig. 3e), longer than wide (ratio = 1.6), paraboloid; anterior margin shallowly concave, lateral margins shallowly convex, posterior margin convex and with a strong spade-shaped median projection, basally flanked on each side by deep notches. Ovipositor in lateral view: each valve of the dorsal pair with dorsal surface convex, with five small dorsal crenulations, and apically curved upwards; each valve of the ventral pair with ventral surface convex, with one small ventral crenulation and apically curved downwards. See figures 1, 3c-e and table I. Variation. Size varies from 24.00-30.65 mm in the types, with slight variations in proportions and relative measurements of several structures (tab. I).

Male: Unknown.
Coloration is essentially identical in the four types. The few minor differences are all artifacts of differential preservation.
The number of antennal flagellomeres is 21/21 except in the paratopotype, with 22 in its single preserved antenna (left).
The subgenital plate in the paratypes from Ojito de Agua and Piedra La Vela differs from holotype: the median projection of the posterior margin is lanceolate to triangular and lacks both laterobasal notches.

Comparisons.
A. baracoae n. sp. is easily distinguished from the three Hispaniolan members of the genus by the following characters: 1) Size larger. 2) Coloration unstriped reddish brown. 3) Tegmina present.
Distribution ( fig. 4). This species is known from three localities, scattered across the Sagua-Baracoa Mountains of northeastern Cuba.
Ecological notes. According to its original label, the holotype of A. baracoae n. sp. was captured on the vegetation.
The paratype from Piedra La Vela is the only specimen with complete ecological data. According to the field notes provided by its collector (R. Teruel, pers. comm.), it was found at early afternoon in a sunny but cold winter day, on the bare ground of a trail crossing the core of a sclerophyll scrub (locally known as "charrascal"), which is a very peculiar vegetation type endemic to the Sagua-Baracoa Mountains ( fig. 5). Despite receiving more than 2,000 mm of annual rainfall, it is hot, dry and xerophytic due to the edaphic drought (the water does not penetrate the hardened laterite and serpentinite soil and evaporates quickly).
The three known collecting sites are located deep inside intramontane valleys ( fig. 4b), at medium altitudes ranging from 300-700 m a.s.l. According to Reyes & Acosta Cantillo (2005), three main adjacent vegetation types are dominant in these mountains: pine forest, rainforest and sclerophyll scrub ( fig. 5). Figure 6. Hispaniolan specimens of the genus examined for comparison, male (left) and female (right), full-body dorsal views: a) Acridurus neibanus, paratypes; b) Acridurus robustus, paratypes; c) Acridurus yayitas, not types (see wrong paratype labels and origin distinct from type-locality). Plate composed from original photos courtesy Solanlly Carrero.

General remarks
This new species fits the current diagnosis of Acridurus in all characters given by Perez et al. (1995), with the single exception of possessing tegminae (absent in the three Hispaniolan species). This character alone does not support the separation of the single Cuban species into a distinct genus as previously suggested by Yong & Perez-Gelabert (2014: 412), because it is obviously useless at this taxonomic level. It is well-known that the complete range of variation from entirely apterous to full-winged occurs in many American genera of Acrididae, e.g., Boopedon Thomas, 1870, Melanoplus Stål, 1873, Orphulella Giglio-Tos, 1894, Phaedrotettix Scudder, 1897, Philocleon Scudder, 1897and Proctolabus Saussure, 1859(Fontana et al., 2008S. Yong pers. obs.). During this study were also examined paratypes of both sexes of all Hispaniolan species of Acridurus (see below), and females were found to differ from A. baracoae n. sp. only in standard species-level characters such as size, coloration and minor body proportions.
It is worth mentioning here that the current generic diagnosis of Acridurus is not at all satisfactory and needs a thorough revision, which is already in progress (S. Yong, in preparation). Perez et al. (1995: 162-163) based the genus on nine characters, but three of them (33%) involve coloration, which is of little validity at this taxonomic level. As discussed above for tegminae, coloration is so highly variable within most genera of Acrididae that it lacks diagnostic value, in some cases even at species level.
Similarly, the distinction of the Hispaniolan species of the genus is not satisfactory either. The 22year old original descriptions by Perez et al. (1995) still remain the only available, and are very short, incomplete and based on few characters, part of them too weak and difficult to interpret, especially because no thorough study of variability was attempted therein. These problems are especially evident on table 2 of that paper (Perez et al., 1995: 163): it is titled "Comparison of Acridurus species (males)" [sic], but columns pertaining to A. yayitas and A. neibanus are identical for all five characters, thus, their distinction is impossible. Another example is that the original "description and diagnosis" [sic] of A. yayitas explicitly mentions female characters, but the types-series includes only two males and five juveniles (Perez et al., 1995: 164).