Ambrysus brailovskyi Reynoso & Sites, 2019

Reynoso-Velasco, Daniel & Sites, Robert W., 2019, Descriptions of four new species of the Ambrysus signoreti Stål species complex (Heteroptera: Nepomorpha: Naucoridae), Zootaxa 4615 (2), pp. 285-302 : 286-290

Ambrysus brailovskyi Reynoso & Sites NEW SPECIES

(Figs. 1–3)

Description. Macropterous female. HOLOTYPE, length 11.50; maximum width 7.55. Paratypes (n = 10), length 10.72–11.44 (mean = 11.17); maximum width 6.72–7.52 (mean = 7.14). General shape elongate, parallel-sided; widest across embolia (Fig. 1A). Overall dorsal coloration of hemelytra brown to dark brown with yellowish brown marks; head and pronotum yellowish with brown marks; legs yellowish brown. Dorsal surface coarsely punctate. Ventral coloration of head and thorax yellowish, abdomen with yellowish pubescence.

Head. Head length 1.68; maximum width 3.16. Mostly yellowish with brown marks along medial line and

Thorax. Pronotum coarsely punctate, ground color yellowish, brown marking posteromedially, brown longitudinal line behind eye; transverse sulcus marking anterior border of transverse band in posterior 1/4; transverse band yellowish anteriorly, brown posteriorly; lateral margins yellowish, convergent, evenly convex, explanate; posterior margin almost straight; anterior margin deeply concave between eyes to embrace convex posterior margin of head; posterolateral corners rounded; width 3.1× length; length at midline 2.08; maximum width at posterolateral corners 6.44. Prothorax ventrally pruinose throughout, except laterally; apices of propleura meeting at midline, not appressed to prosternellum; propleuron yellowish, light brown posteriorly, medial 2/3 of posterior margin with golden setae. Probasisternum with sharp median carina and row of setae lateral to carina. Prosternellum not covered by apices of propleura. Scutellum coarsely punctate, triangular, yellowish brown, two reniform to ovate brown marks medially, width 2.2× length, width 4.32, length 1.92. Hemelytra densely punctate, brown to dark brown, length 8.0 (chord measurement); corium dark brown, yellowish irregularly shaped and brown-spotted yellowish checkmarkshaped markings at lateral and posterior margins, respectively (Fig. 1A). Clavus dark brown in lateral half, brown in mesal half with dark brown close to base and apex, length 3.8× width, length 4.56, width 1.20; claval commissure dark brown, length 1.12. Embolium length 3.48, greatest width 1.11; lateral margin convex, yellowish in anterior 2/3, brown posteriorly. Membrane dark brown (Fig. 1A). Hindwings extending to posterior margin of tergum VI. Mesobasisternum tumescence negligible, with sulcus on midline continuing through triangular mesosternellum. Metasternellum (=metaxyphus) transverse, subtriangular, with median carina.

Legs. All leg segments yellowish brown. Profemur yellowish brown; posterior margin with row of tightly arranged setae in basal 2/3, row of short brown spines along middle third; anterior margin with dense pad of setae without associated spines. Protibia and -tarsus with occlusal inner surface flattened and with spatulate setae; tarsus immovable, one-segmented; pretarsal claw single, minute, triangular. Procoxa with cluster of stout, brown anteromedial spines. Meso- and metacoxae partially recessed into thorax. Meso- and metafemora with row of short, light brown spines on anterior margin; spines restricted to basal half on mesofemur, nearly full length of metafemur. Mesotibia with ventrolateral and dorsolateral rows of stout reddish-brown spines; mesolateral rows intermixed with combs of two to five spines. Metatibia with ventrolateral and dorsolateral rows of stout reddish-brown spines. Meso- and metatibiae with semi-circlet of spines at apex of dorsal and mesal margins; two comb rows of stout spines near apex of ventral margin. Meso- and metatibiae and metatarsus with long, yellow swimming hairs; hairs profuse on metatibia and -tarsus. Meso- and metapretarsi with paired claws slender, gently curved, with small basal tooth. Leg measurements as follows: foreleg, femur 2.52, tibia 2.00, tarsus 0.48; middle leg, femur 2.60, tibia 2.30, tarsomeres 1–3, 0.22, 0.45, 0.51; hind leg, femur 3.48, tibia 4.00, tarsomeres 1–3, 0.25, 0.82, 0.72.

Abdomen. Dorsally with lateral margins of III–VI exposed, each brown in anterior 1/3 and light brown posteriorly; lateral margins of II–basal half of III nearly smooth and distal half of III–VI finely serrate, marginal row of profuse and short yellow setae, group of trichobothria near posterolateral corners. Posterolateral corner of II (visible ventrally) narrowly rounded, right angled, III–VII acute. Ventrally yellowish, with dense pile of fine hairs. Lateral margin with thin, glabrous band. Glabrous rounded to oval patches near spiracles on laterosternites II–VI. Mediosternite VII (subgenital plate) asymmetrical, width 1.2× length; length at midline 1.17; maximum width 1.42; low lateral lobe at base of left margin; posterolateral corners pointed; wide central lobe notched giving the appearance of two pointed lobes, lobes produced posteriorly further than posterolateral corners (Fig. 1B).

Macropterous male. Paratypes (n = 10), length 9.92–10.48 (mean = 10.21); maximum width 6.32–6.88 (mean = 6.66). Coloration, setation, pronotum proportions, posterolateral corners of pronotum, scutellum proportions, embolium length generally same as for holotype. Otherwise hindwings extending to posterior margin of tergum V. Accessory genitalic process of tergum VI slender, extending nearly straight posteriorly in basal 2/3, abruptly curved to right at approximately 70 degree angle in apical 1/3, apex narrowly rounded (Fig. 1C). Medial lobes of tergum VIII (pseudoparameres) symmetrical, laterally produced, posterolateral and posteromesal corners broadly rounded (Fig. 1D). Phallosoma elongate, linear, slender, slightly constricted basally; left endosomal sclerite subtriangular (lateral view), with transverse row of small denticles apically; right endosomal sclerite small, rounded, with a few denticles anteriorly (Fig. 1E). Parameres symmetrical, almost as long as maximum width, mesal margin rounded, setae emanating from distal 1/3 of dorsal surface. Proctiger as long as width at base. Pygophore with elongate setae sparsely distributed over most of surface, with thick brush of elongate setae on posterior margin (Fig. 1F).

Discussion. Based on the generalized shape of the female SGP and the male phallosoma with the right endosomal sclerite small and rounded we consider this species to be closely related to A. cayo Sites & Shepard , A. colimanus Polhemus & Polhemus , A. inflatus La Rivers , and A. quadracies La Rivers.

Diagnostic features and comparative notes. Females of this species exhibit a characteristic SGP with a low and rounded lateral lobe at the base of the left margin. The central lobe on the posterior margin is deeply notched and appears as two pointed lobes that are produced further than the posterolateral corners. A similar morphology of the posterior margin of the SGP is present in the species A. cayo , A. colimanus , A. inflatus , and A. quadracies , although in A. cayo , A. colimanus , and A. quadracies the posterolateral corners and central notched lobe are almost at the same level. In A. inflatus , the posterolateral corners are more pointed, the notched central lobe is narrower, and the lateral lobe is at mid-length of the left margin. We have noticed some variation on the SGP of A. brailovskyi that includes a low and rounded lateral lobe at the base of the right margin (symmetrical SGP) and the central lobe on the posterior margin appearing as two rounded lobes.

Habitat description. The type locality at San José Veracruz (L-1808) is in the northwestern area of the Mexican state of Chiapas, at an elevation of 862 meters. At this locality the stream is shallow, 3–10 meters wide, and with limestone boulders and cobble in the channel ( Fig. 2 ). The microhabitat where most specimens of A. brailovskyi were found was the protected area behind rocks in the channel.

Distribution. This species is only known from the Mexican state of Chiapas ( Fig. 3 ). Ambrysus brailovskyi is distributed in the highlands (569–1010 meters) of the Chiapas biogeographic province. The species was collected syntopically with several species of Ambrysus , including with A. pulchellus Montandon and A. spicatus La Rivers at Río Matasano (L-1348), with A. circumcinctus Montandon at Río Prusia (L-1345), and with A. sitesi n. sp. at Finca Prusia (12-V-1985), Río Prusia (L-1345), Río Matasano (L-1348), and the Tenejapa municipality (14-VII-1964). Ambrysus brailovskyi also was collected syntopically with the rock-clinging saucer bug Cataractocoris macrocephalus (Montandon) at Río Prusia (L-1345).

Etymology. This species is named in honor of our colleague Professor Harry Brailovsky, of the Universidad Nacional Autónoma de México, to recognize his remarkable career on the study of Heteroptera, which heretofore includes the descriptions of 153 genera and 987 species.

Repositories. The holotype and some paratypes will be deposited in the Colección Entomológica del Instituto de Ecología A.C. (Xalapa); additional paratypes will be deposited in the Colección Nacional de Insectos (Mexico City), Enns Entomology Museum (Columbia), and the United States National Museum of Natural History (Washington D.C.).

Type material examined. HOLOTYPE ♀. MÉXICO: CHIAPAS: Mpio. Chilón, San José Veracruz, 17°04’23.9’’N, 91°58’05.7’’W, 862 m, 02-Jun-2014, L-1808, DRV & PRH colls . PARATYPES: same data as holotype (7♂, 13♀ UMC) ; [Mpio. Ángel Albino Corzo], Finca Prusia, 12-V-85, M Vértiz / Colección del Instituto de Biología , UNAM. México, D.F (1♂ CNIN) ; Mpio. Ángel Albino Corzo, 1 km S of Finca Prusia, Río Prusia , 15º43’23.3’’N, 92º47’46.5’’W, 1010 m, 18-May-2012, L-1345, DRV & PRH colls. (3♂, 2♀ UMC) ; Mpio. Chilón, Guadalupe Paxila, Río Paxila , 17°07’01.6’’N, 92°01’43.9’’W, 569 m, 02-Jun-2014, L-1809, DRV & PRH colls. (4♂, 4♀ IEXA) ; Mpio. Chilón, Jet-Mesil, Río Bolontina , 17°07’11.1’’N, 92°05’18.8’’W, 584 m, 02-Jun-2014, L- 1810, DRV & PRH colls. (1♂, 2♀ IEXA) ; [Mpio. Ixhuatán], 4 mi N of Tapiula [ Tapilula ], CL 1097, 5 May 1964, JT & MS Polhemus / C.J. Drake Accession (1♂ USNM) ; [Mpio. Ixtacomitán], Ixtacomitán, Río Blanco, 10-XII- 85, cols. F Arias, L Cervantes y R Barba / Colección del Instituto de Biología , UNAM. México, D.F. (3♂, 2♀ CNIN) ; Mpio. Ocosingo, Las Lajas, Río Las Lajas , 16°57’13.6’’N, 92°06’51.1’’W, 922 m, 02-Jun-2014, L-1811, DRV & PRH colls. (1♂, 1♀ IEXA) ; Mpio. Siltepec, Matasano, Río Matasano , 15º36’13.7’’N, 92º33’37.1’’W, 950 m, 19-May-2012, L-1348, DRV & PRH colls. (3♂, 3♀ UMC) ; Mpio. Tenejapa, ponds in stream above Habenal / 14.VII.1964, coll. D Breedlove / C.J. Drake Accession / CAS (1♀ USNM) ; km 88 carr. Palenque-Ocosingo, 8-V-85, F Arias / Colección del Instituto de Biología , UNAM. México, D.F (1♀ CNIN) .

Figures

FIGURE 2. Type locality of Ambrysus brailovskyi n. sp. at San José Veracruz (Chiapas, Mexico). Inset: DRV (right) and PRH (left) collecting in the protected area behind rocks, where specimens of this species were commonly found.

FIGURE 3. Distribution of Ambrysus brailovskyi n. sp., A. henryi n. sp., A. schuhi n. sp., and A. sitesi n. sp. in Mexico and Guatemala (color coded stars indicate the type localities).