Limnocoris amazonensis Rodrigues & Sites 2023, NEW SPECIES
Creators: name: Rodrigues, Higor D. D.
name: Sites, Robert W.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Naucoridae
Limnocoris
Limnocoris amazonensis

description: Limnocoris amazonensis Rodrigues & Sites NEW SPECIES
(Figs. 2, 6A–B, 13A)
Description. Female – hindwing brachypterous. HOLOTYPE, length 7.82; maximum width 5.70. General shape oval; widest across mid-length of embolia (Figs. 2A–B) Overall dorsal coloration brown, dark mottled on head, pronotum, and hemelytra. Dorsal surface with fine granulations throughout, except punctate hemelytral membrane (Fig. 2A). Ventral coloration brown (Fig. 2B).
Head. Length 1.15, maximum width 2.70. Mostly brown with dark-brown median markings becoming wider posteriorly, weakly punctate. Synthlipsis 1.35. Eyes not raised above level of vertex or pronotum; thin band of cuticle lateral to anterior third of eye. Anterior and posterior margins between eyes shallowly convex. Maxillary plate broad basally, anterior edge triangular. Labrum width 1.11× length, distal margin narrowly rounded. Labium with three visible brown segments, with last segment darker, extending 0.50 beyond labrum not including extruded stylets. Antenna length 0.65; not exceeding lateral margin of eye; pedicel quadrate; flagellomeres slender, not partially fused, with long setae; segments 1–4 lengths: 0.04, 0.25, 0.21, 0.13. Postgenal tubercle on posteroventral midline.
Thorax. Pronotum ground color brown, lighter laterally; mottled with dark-brown markings on rectangular area behind eyes; smaller markings near mid-lateral area; shallow sulcus marking anterior border of transverse band in posterior third; anterior margin shallowly convex between eyes; lateral margins convergent anteriorly, evenly convex; posterior margin shallowly concave medially; posterolateral corner rounded (Fig. 2A); greatest width 3.71× length at midline; length at midline 1.40; maximum with at posterolateral corners 5.20. Prothorax ventrally brown, with posterior half of prosternellum dark-brown. Propleuron with shagreened area not extended posteriorly along lateral margin (Fig. 2B); elongate golden setae concentrated near proacetabulum; posterior margin convex at mid-length; posteromesal corner near prosternellum deflexed ventrally as a papilla. Probasisternum with a weak carina indistinctly bifid in lateral view, not projecting anteriorly. Scutellum triangular; mostly dark-brown, yellowish-brown laterally; width 2.70, length 1.20. Hemelytra brown, with irregular dark-brown markings on corium and clavus; membrane mottled with dark-brown; length 5.80 (chord measurement). Embolium greatest width 0.70, lateral margin convex, serrated, yellowish-brown on anterior half, dark-brown posteriorly. Claval suture present, but suppressed; intraclaval suture absent. Hindwings reduced, reaching anterior margin of abdominal tergum IV. Region between mesobasisternum and mesoepisternum with longitudinal row of elongate golden setae. Mesosternal carina with median ridge straight, fossa deflexed ventrad, oval, poorly crenulated at lateral margins, and contains short golden hairs inside rim and on anterior projection (Fig. 2C); posterior margin excavated in lateral view after fossa (Fig. 2E). Metasternal carina oval, depressed medially (Fig. 2C); posterior margin excavated in lateral view (Fig. 2E). Metapleuron covered with elongate golden setae on posterior region.
Legs. All legs segments brown, except dark-brown apex of tarsomere III of middle and hind legs. Procoxa with cluster of stout, brown anteromedial spines. Profemur anterior margin with dense pad of light-brown setae without associated spines, posterior margin with row of short brown spines along basal half. Protibia and tarsus with occlusal inner surface flattened; tarsus one-segmented, immovable; pretarsal claw single, minute, triangular. Meso- and metacoxae partially recessed into thorax. Meso- and metafemora with row of short, brown spines on anterior margin. Meso- and metatibiae with ventrolateral, ventromedial, dorsolateral, and dorsomedial rows of stout brownish spines; meso- and metatibiae with two transverse rows of spines distally, one each on lateral and mesal margins. Meso- and metatibiae and metatarsus with long, pale swimming hairs, hairs profuse on metatibia and - tarsus. Meso- and metapretarsi with paired claws slender, gently curved, with minute basal tooth. Leg measurements as follows: fore leg, femur 2.05, tibia 1.20, tarsus 0.53; middle leg, femur 1.90, tibia 1.35, tarsomeres 1–3, 0.10, 0.30, 0.35; hind leg, femur 2.65, tibia 2.70, tarsomeres 1–3, 0.15, 0.65, 0.65.
Abdomen. Dorsally with lateral margins of terga III–VII exposed; terga III–VI dark-brown anteriorly, light-brown posteriorly (Fig. 2A); marginal row of short yellow setae, and group of trichobothria near posterolateral corners (collapsed in holotype). Lateral margin of abdomen serrated, tergum V with 18 teeth. Posterolateral corners of II–V right angled, not spinose, VI acute. Sterna mostly brown; elongate golden setae generally dispersed, concentrated near midline (Fig. 2D); sternum II with sinuous row of elongate golden setae. Tergum VI symmetrical. Subgenital plate broad, almost as wide as long, width 0.98 × length; length at midline 1.38; maximum width 1.35; lateral margin with tuft of elongate golden setae at mid-length (collapsed in holotype), ending in a narrowly rounded apex; laterosternite VII tapered at apex (Fig. 2D).
Male – hindwing brachypterous. Paratypes (n = 2), length 8.05–8.13; maximum width 5.60–5.65. Similar to female in general structure and coloration, except as follows: Mediotergite VI with accessory genitalic process narrowly rounded; posterior margin without notch on left side. Mediotergite VII posterior margin forming two pairs of small rounded lobes, one medial and one lateral; mesal margin of laterotergite VII convex (Fig. 6A). Lateral lobe of tergum VIII with lateral margin straight in anterior half; left medial lobe angled laterally and truncate at apex, with posteromesal corner narrowly rounded; right medial lobe twisted in distal third (Fig. 6B).
Diagnosis. Body length 7.82–8.13, body width 5.60–5.70. The shagreened area of the propleuron is not extended posteriorly along the lateral margin (Fig. 2B). The mesosternal carina has the median ridge straight, and the fossa is deflexed ventrad, oval, poorly crenulated at the lateral margins, and contains short golden hairs inside the rim and on the anterior projection; the posterior margin is excavated in lateral view after the fossa (Figs. 2C, E). Male mediotergite VII has the posterior margin with two pairs of small rounded lobes, one medial and one lateral (Fig. 6A). The female subgenital plate is broad, ending in a narrowly rounded apex (Fig. 2D).
Comparative notes. This species has a propleuron shagreened pattern similar to that of L. flavescens n. sp., where in both species the shagreened area is not extended posteriorly along the lateral margin. However, these two species are easily separated by the shapes of the meso- and metasternal carinae. In L. amazonensis, the fossa of the meso- and metasternal carinae are oval and developed (Fig. 2C, 2E), whereas in L. flavescens these two carinae are narrow and, specifically for the metasternal carina, the fossa is indistinct (Figs. 5C, E); in addition, they differ in coloration of the body and the shapes of male abdominal terga VI–VIII.
Some species associated with the slopes of the Andes Mountains also share with L. amazonensis a similar pattern of the shagreened area of the propleuron (not or slightly extending posteriorly along the lateral margin) and the shape of male abdominal tergum VII (where the posterior margin forms four small, rounded lobes); these are L. distanti Montandon, L. elongatus Rodrigues & Sites, L. malkini La Rivers, L. ochraceus Montandon, and L. pallescens (Stål). Important features to distinguish L. amazonensis from the Andean species are the shapes of the mesosternal carina and female subgenital plate.
Distribution. This species is known only from the type locality, in the Serra da Mocidade, state of Roraima, northern Brazil (Fig. 13A).
Etymology. The specific epithet refers to the region in which the specimens were collected.
Type material examined. All specimens brachypterous. HOLOTYPE ♀: BRAZIL, Roraima: Caracaraí, Serra da Mocidade, base II, igarapé na trilha do pico, 01º42’23”N, 61º47’08”W, 01.II.2016, #10, J.M.C. Nascimento col. (INPA). PARATYPES: same data as holotype (1♁ INPA; 1♁ MZUSP).
description: Published as part of Rodrigues, Higor D. D. & Sites, Robert W., 2023, Revision of Limnocoris Stål (Heteroptera: Nepomorpha: Naucoridae) of the Guiana Shield and Amazon regions, pp. 44-76 in Zootaxa 5284 (1) on pages 47-51, DOI: 10.11646/zootaxa.5284.1.2, http://zenodo.org/record/7918947