Ambrysus henryi 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 : 290-294

Ambrysus henryi Reynoso & Sites NEW SPECIES

( Figs. 3–5 )

Description. Macropterous female. HOLOTYPE, length 12.12; maximum width 8.12. Paratypes (n = 10), length 10.64–12.48 (mean = 11.73); maximum width 6.88–8.16 (mean = 7.60). General shape ovate; widest across embolia (Fig. 4A). Overall dorsal coloration of hemelytra dark brown to black with yellowish brown marks; head and pronotum yellowish brown with brown marks; legs yellowish brown. Dorsal surface coarsely punctate. Ventral coloration of head and thorax yellowish, abdomen with yellowish pubescence.

Head. Head length 1.76; maximum width 3.48. Mostly yellowish brown with brown marks along midline and posteriorly; coarsely punctate. Eyes convergent anteriorly, synthlipsis 1.72; thin band of cuticle along posterolateral margin of eye; eyes not raised above level of vertex or pronotum. Anterior margin between eyes slightly convex, extending anteriorly in front of eyes 8.5% of head length; posterior margin between eyes strongly convex, extending posteriorly 30.6% of head length. Labrum width 1.9× length, evenly rounded. Labium with three visible yellowish brown segments, darkening distally, extending 0.37 beyond labrum not including extruded stylets. Antennal proportions 3:19:21:11, length 0.81, extending to lateral margin of eye, elongate hairs on segment 4 and distal half of 3.

Thorax. Pronotum coarsely punctate, ground color yellowish brown, brown marking posteromedially, black longitudinal line behind eye; transverse sulcus marking anterior border of transverse band in posterior 1/3; 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 2.8× length; length at midline 2.52; maximum width at posterolateral corners 7.06. 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, brown, two reniform to ovate dark brown marks medially, width 2.3× length, width 4.76, length 2.04. Hemelytra densely punctate, dark brown to black, length 8.96 (chord measurement); corium dark brown, brown suboval and yellowish brown checkmark-shaped markings at lateral and posterior margins, respectively. Clavus dark brown to black, yellow at each end, faint yellowish spot near middle, length 3.8× width, length 4.80, width 1.24; claval commissure black, length 1.20. Embolium length 3.84, greatest width 1.17; lateral margin convex, yellowish brown in anterior 2/3, dark brown posteriorly. Membrane black (Fig. 4A). Hindwings extending to posterior margin of tergum VII. 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; 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 six spines. Metatibia with ventrolateral and dorsolateral rows of stout reddish-brown spines. Meso- and metatibiae with semi-circlet of spines at apices on dorsal and mesal margins; two comb rows of stout spines near apices on 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 2.65, tibia 1.90, tarsus 0.52; middle leg, femur 2.75, tibia 2.37, tarsomeres 1–3, 0.18, 0.37, 0.52; hind leg, femur 3.72, tibia 4.04, tarsomeres 1–3, 0.25, 0.84, 0.73.

Abdomen. Dorsally with lateral margins of III–VI exposed, each brown in anterior 1/3 and light brown posteriorly; lateral margins of II smooth and 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–VII. Mediosternite VII (subgenital plate) symmetrical, subtriangular, width 1.05× length; length at midline 1.18; maximum width 1.24; inconspicuous posterolateral corners; apex truncate (Fig. 4B).

Macropterous male. Paratypes (n = 10), length 10.32–11.68 (mean = 10.87); maximum width 6.56–7.52 (mean = 7.06). 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 VI. Accessory genitalic process of tergum VI robust, abruptly curved to right close to the base at approximately 90 degree angle, apex narrowly rounded (Fig. 4C). Medial lobes of tergum VIII (pseudoparameres) symmetrical, posterolaterally produced, posterolateral corner broadly rounded, extending posteriorly further than posteromesal corner (Fig. 4D). Phallosoma elongate, linear, slender, slightly constricted basally; left endosomal sclerite subtriangular (lateral view), with group of small denticles apically; right endosomal sclerite knob-like, with conspicuous denticles (Fig.

Discussion. This species superficially resembles A. hydor La Rivers , although A. henryi is narrower and the posterolateral corners of abdominal segments III–V are less produced. The morphology of the endosomal sclerites of the males suggests that A. henryi is related to A. dyticus La Rivers , A. hydor , A. magniceps La Rivers , A. occidentalis La Rivers , A. scalenus La Rivers , and A. sonorensis in the A. signoreti species complex.

Diagnostic features and comparative notes. Females of this species exhibit a unique subtriangular and truncate SGP. Another species from this complex that presents the SGP with similar inconspicuous posterolateral corners is A. sonorensis ; however, this species has clear lateral lobes and the SGP is almost as wide as long (quadrate). The AGP exhibited by males of A. henryi is the widest among species of this complex. Males of A. inflatus present a similar AGP, although it is narrower and less strongly curved.

Habitat description. The type locality at Río San Juan (L-1904) is in the southern area of the Mexican state of Oaxaca, on the Sierra Madre del Sur Mountain Range, at an elevation of 400 meters. At this locality the river is shallow, 3–6 meters wide, and the substratum is mainly composed of gravel and cobble ( Fig. 5 ). The microhabitat where we collected this species was among rocks, close to the river margins.

Distribution. This species occurs in the southern Mexican states of Chiapas, Guerrero, and Oaxaca ( Fig. 3 ). Ambrysus henryi is distributed in the Chiapas (Chiapas), Mexican Pacific Coast (Chiapas, Oaxaca), and Sierra Madre del Sur (Guerrero, Oaxaca) biogeographic provinces. In the state of Oaxaca, this species was collected syntopically with various congeners, including A. angularis La Rivers , A. baeus Polhemus & Polhemus , A. pudicus Stål , and A. spicatus at Río San Juan (L-1904, the type locality of A. henryi ); with A. baeus and A. spicatus at Río San Juan (L-1375, L-1376, L-1905); with A. baeus , A. pulchellus , and A. schuhi n. sp. at Río Rana (L-1380); with A. baeus , A. schuhi n. sp., A. sitesi n. sp., and A. spicatus at Río Rana (L-1906); and with A. angularis , A. parviceps Montandon , A. pudicus , and A. pulchellus at Pte. Yutaniñe (L-1385) and Mártires de Tacubaya (L-1390). In the state of Chiapas, at the Velo de Novia Waterfall (L-1359, L-1903), this species was found syntopically with A. pudicus , A. pulchellus , and the three known species in genus Cataractocoris Usinger. This waterfall is the type locality of Cataractocoris shepardi Sites, Reynoso & Novelo.

Etymology. The specific epithet henryi is in honor of our colleague Professor Thomas J. Henry, of the United States National Museum of Natural History, to commemorate a lifetime dedicated to the study of Heteroptera. Among his numerous accomplishments are the descriptions of approximately 300 insect taxa.

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: OAXACA: Mpio. Candelaria Loxicha, km 207 carr. Oaxaca-San Pedro Pochutla, Candelaria Loxicha, Río San Juan , 15º55’32.5’’N, 96º29’12.6’’W, 400 m, L-1904, 02-Apr-2015, DRV, Sites, Shepard, Barr & PRH colls . PARATYPES: same data as holotype (4♂, 1♀ IEXA) ; same but 25-May-2012, L-1375, DRV & PRH colls. (1♂, 1♀ UMC) ; Mpio. Candelaria Loxicha, Candelaria Loxicha, Río San Juan at Pte. San Juan , 15º55’32.9’’N, 96º29’25’’W, 403 m, 26-May-2012, L-1376, DRV & PRH colls. (2♀ UMC) ; same but 02-Apr-2015, L-1905, DRV, Sites, Shepard, Barr & PRH colls. (1♂ IEXA) ; Mpio. Mártires de Tacubaya, Mártires de Tacubaya , 16º34’41.1’’N, 98º13’08.7’’W, 206 m, L-1390, 29-May-2012, DRV & PRH colls. (1♂, 1♀ IEXA) ; Mpio. San Gabriel Mixtepec, km 194 carr. Puerto Escondido-Oaxaca, San Gabriel Mixtepec , Río Rana , 16º06’06.3’’N, 97º03’52.9’’W, 712 m, L-1380, DRV & PRH colls. (1♂, 1♀ UMC) ; same but 03-Apr-2015, L-1906, DRV, Sites, Shepard, Barr & PRH colls. (1♂, 1♀ IEXA, 3♂, 7♀ UMC) ; Mpio. San Miguel Tlacamama, San Miguel Tlacamama, Pte. Yutaniñe , 16º25’32.6’’N, 98º03’29.2’’W, 260 m, L-1385, 28-May-2012, DRV & PRH colls. (1♂ UMC) ; 29 mi W [Magdalena] Tequisistlán, CL 1064, 30 Apr 1964, JT & MS Polhemus / C.J. Drake Accession (1♂ USNM) . CHIAPAS: Mpio. La Concordia, Km 17 carr. Jaltenango-Rev. Mexicana , 15º58’12.6’’N 92º48’18.7’’W, 562 m, L-1316, 07-Jan-2012, submerged veg. DRV coll. (1♀ UMC) ; Mpio. Tonalá, Velo de Novia Waterfall, 15º55’11.3’’N, 93º29’45.9’’W, 144 m, nr. Pte. Las Hermanas , 21-May-2012, L-1359, DRV & PRH colls. (1♀ UMC) ; same but 01-Apr-2015, L-1903, DRV, Sites, Shepard, Barr & PRH colls. (3♂, 3♀ CNIN; 6♂, 4♀ IEXA; 5♂, 7♀ UMC) . GUERRERO: [Mpio. Chilpancingo de Los Bravo], Agua de Obispo, 8-37, P Roveglia / Colección del Instituto de Biología , UNAM. México D.F. (1♀ CNIN) .

Figures

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).

FIGURE 5. Type locality of Ambrysus henryi n. sp. at Río San Juan (Oaxaca, Mexico) with live specimen inset.