Armasius iberianus Perez-Gelabert & Yong, 2014

Yong, Sheyla, 2017, The adult male of the little-known pygmy grasshopper Armasius iberianus Perez-Gelabert & Yong, 2014 (Orthoptera: Tetrigidae: Cladonotinae), Ecologica Montenegrina 15, pp. 1-9 : 2-7

Armasius iberianus Perez-Gelabert & Yong, 2014

Figures 1–5 ; Table I

"New Genus, New species": Yong & Perez-Gelabert, 2014: 406.

Armasius iberianus Perez-Gelabert & Yong, 2014: 44–50 , figs. 1–5.

Type data. "Monte Iberia. Nibujón. Bcoa. Ote. III-1972 L. Armas" [actually: CUBA: Guantánamo Province: Baracoa Municipality: Monte Iberia High Plateau (20°28'40"N - 74°43'50"W, 610 m a.s.l.); on tree trunk 0.50 m above ground, montane rainforest; 5/March/1972; L. F. de Armas]; adult female holotype ( IES, dry pinned). Note: this specimen was officially loaned to Daniel E. Perez-Gelabert in September 2013, but it has not been returned yet to IES collection.

Additional specimen examined. CUBA: Holguín Province [first record]: Moa Municipality: El Toldo High Plateau : source of Piloto River (20°28'39"N - 74°53'58"W, 850 m a.s.l.); in leaf litter, montane rainforest; 14/July/1997; R. Teruel; one adult male ( SY, in ethanol 80%).

Diagnosis (emended). This species can be recognized from all other Caribbean Cladonotinae genera by the unique shape of the pronotum (fig. 3): it covers almost the whole body, has its anterior half only slightly elevated and its lateral lobes are modified into an erect, large and sharp projection which is shaped triangularly (male) to spiniformly (female) and dorsolaterally flattened (male). Sexual secondary dimorphism is evident in size, but also in pronotum shape (fig. 3a–b) i.e., in male it is narrower, less elevated posteriorly and the lateral lobes are slightly less developed.

Adult male.

Size medium for the subfamily (total length 8.75 mm). General coloration highly cryptic: dark brown, extensively variegated with black and pale yellowish-brown all over the body and appendages, tibiae and tarsi conspicuously annulated with dark and pale pattern. See figure 1 and table I.

Head (figs. 1–2a). Relatively small, wider than long (ratio = 1.6). Tegument rugose, scabrose, dull and essentially glabrous. Vertex convex in lateral view, slightly covered by the anterior margin of pronotum in dorsal view. Fastigium strongly modified into the medial carina, which is conspicuously raised between the eyes, strongly compressed in frontal view, semicircular in lateral view and partially covered by the anterior margin of pronotum in dorsal view. Eyes large, round, prominent and reaching the anterior margin of pronotum. Lateral ocelli minute, situated on the upper margin of frontal costa. Frontal costa widely forked and inverted U-shaped in frontal view. Genae convex in frontal view. Antennal sockets situated below lower margin of the eyes. Antennae standard for Tetrigidae in size and shape, with 8/8 flagellomeres; scapus subcylindrical, slightly depressed, wider than long (ratio = 0.7), oval in cross-section, essentially glabrous; pedicel globular, same length as scapus.

Thorax (figs. 1a–b). Tegument rugose, scabrose, dull and essentially glabrous. Pronotum longer than wide (ratio = 1.8), covering almost the entire body, strongly tapering posteriorly in dorsal view, in lateral view slightly elevated anteriorly and with posterior tip slightly raised; apex of the anterior margin not projecting beyond the head; median carina smooth, evenly sinuose and strongly compressed. Lateral lobes erect, large and sharp, each projecting as a triangular and dorsolaterally flattened structure. External lateral carina prominent, sinuose and distally convergent with median carina. Tegmina and hind wings absent.

Legs (fig. 1). Profemur (fig. 3d) subcylindrical and compressed laterally, with upper and lower margins serrate, the latter with a single lappet which is poorly developed and located in submedial position; protibiae rectangular and slightly longer than profemur (ratio = 1.0), very slender and straight, covered by short and stout setae and with all carinae very well marked. Mid femur subcylindrical and compressed laterally, with upper and lower margins serrate, the latter with a single lappet which is poorly developed and located in medial position; mesotibiae similar in structure to protibiae. Metafemur robust, longer than metatibiae (ratio = 1.2), oval in cross-section, rugose, with dorsoexternal and ventroexternal carina very well marked, lower margin with two lappets which are moderately well developed and located in medial and subdistal position, knees with one genicular tooth and one antegenicular tooth, both large and flattened; metatibiae (left/right) with 5/6 pairs of subapical spines and 5/5 apical spurs curved inwards. Tarsus of the hind legs four segmented, all same length; tarsal claws long.

Abdomen (fig. 1). Long and slender, subcylindrical, evenly tapering posteriorly and covered by the pronotum almost to posterior margin of supranal plate. Tegument rugose, dull. Supranal plate (fig. 2b) longer than wide (ratio = 1.6), teardrop-shaped in dorsal view (i.e., anterior margin narrowly semicircular, lateral margins straight and distally convergent into a triangular tip), sparsely setose. Cerci densely covered by minute setae, short, narrowly conical, with base bulbous. Subgenital plate (fig. 2b), very slightly wider than long (ratio = 1.1), shield-shaped, bulky and coarsely granulose; anterior margin shallowly convex, lateral margins shallowly convex, distally convergent and with distal half coarsely serrate, posterior margin widely V-notched and irregularly serrate; median keel well marked.

Distribution (figs. 4–5). This species is known only from the top of two adjacent high plateaus, El Toldo and Monte Iberia, in the core of the Sagua-Baracoa Mountains of northeastern Cuba. These populations are most likely not isolated, because the vegetation and soil of the facing slopes connecting both high plateaus is continuous and still well-preserved (Rolando Teruel, pers. comm.).

Ecological notes. According to the data supplied by his collector (R. Teruel, personal communication) the adult male of A. iberianus was captured on the leaf litter that covers the ground of the montane rainforest (fig. 5b–c). According to Reyes & Acosta Cantillo (2005), this very humid area receives up to 3,600 mm of annual rainfall and represents one of the best-preserved landscapes in Cuba. Nevertheless, these localities in the future could be drastically impacted by the razing activities of opencast mining, which is extensive and increasing already all over the northern slopes of El Toldo (fig. 5a).

Figures

Figure 1. Armasius iberianus, adult male from El Toldo, full-body views: a) dorsal; b) lateral; c) ventral. Scale bar in millimeters.

Figure 2. Armasius iberianus, adult male from El Toldo, close-up views: a) head, frontal; b) head, lateral; c) apex of abdomen, lateral; d) apex of abdomen, ventral. Scale bars: 1.5 mm (a–b), 1 mm (c–d).

Figure 3. Armasius iberianus, adult male from El Toldo (left) and adult female holotype from Monte Iberia (right), selected views showing sexual secondary dimorphism: a) full-body, dorsal; b) full-body, lateral; c) head, frontal; d) profemur, outer. Scale bars: 5 mm (a–b), 1 mm (c–d). Images of holotype modified from Perez-Gelabert & Yong (2014).

Figure 4. a) The Antilles, showing location of Cuba; b) easternmost Cuba, showing updated geographical distribution of Armasius iberianus in El Toldo (1: new record) and Monte Iberia (2: type locality).

Figure 5. Three views of the habitat of Armasius iberianus: a) south-facing overview of the two high plateaus where this species occurs, showing its close proximity and severe threat due to razing activities of opencast mining; b–c) montane rainforest at El Toldo. Photos courtesy Rolando Teruel (a) and Nicasio Viña Dávila (b–c).