Neomacrocoris usambaricus Montandon

Sites, Robert W. & Mbogho, Aaron Y., 2012, Revision of the African genus Neomacrocoris (Hemiptera: Heteroptera: Nepomorpha: Naucoridae), Zootaxa 3555, pp. 1-39 : 30-33

Neomacrocoris usambaricus Montandon

Figs. 54–56

Neomacrocoris usambaricus Montandon 1913 : Bul. Soc. Rom. Stiinte, 22: 332–334. NEOTYPE by present designation. Label data: Musée du Congo, Tuevo, 2-VIII-1911, R. Mayné / R. det., A, 202 / Neomacrocoris usambaricus 1913 Montandon, det Montandon 1914.

Supplemental redescription. NEOTYPE Ƥ: length 10.96, maximum width 6.78. General shape elongate oval, widest across embolia ( Fig. 54 ); overall coloration dorsally yellowish-brown anteriorly with dark scutellum and hemelytra; ventrally, lateral part of propleura yellow, legs and abdomen light brown, meso- and metasterna dark brown.

Head. Length 2.04, maximum width 2.64. Yellow with two convergent lines of dark brown spots on vertex, dark brown band at posterior margin; projecting beyond eyes 6% of head length. Eyes dark brown; approximately twice as long as wide, length/width 1.12/0.60; inner margins slightly convergent, lateral margins convex; synthlipsis 1.32; posterior margin with fringe of elongate golden hairs in area of postocciput where head normally subducts below pronotum. Labrum yellowish, transverse, subtriangular, apex rounded, width/length 0.82/0.44. Maxillary plate yellow, elongate, ventral margin convex, extending approximately to one-third length of labrum, bordering sides of rostral base. Labium with three visible segments darkening distally from yellowish-brown basal segment to dark orange-brown distal segment, short, extending 0.38 beyond labrum. Antenna short, yellow, hirsute, extending slightly beyond lateral margin of eye.

Thorax. Pronotum broad, highly convex, yellow; disc mostly immaculate; wide, transverse, yellow band along posterior margin with irregular series of large, light brown, longitudinally elongate spots, otherwise immaculate; with small punctures; maximum width 6.12, length at midline 2.72; posterior margin broadly convex; lateral margins strongly convex, convergent anteriorly, distinctly explanate; posterolateral corners rounded; entire surface vaguely rugose; with pale, erect, setae near lateral margins and occasional short, erect setae throughout. Scutellum dark brown; coarsely rugose; with several, erect pale setae; width 3.92, length at midline 2.24; lateral margins slightly convex; mesoscutum partially exposed behind pronotum because of head/pronotum deflexion. Hemelytra brown; punctate; sparse, elongate, thin setae; several thick setae on embolium and adjacent areas of corium; length 7.48 (chord measurement). Clavus distinct, yellow at commissure. Embolium well delineated, lateral margin arcuate, yellowish anteriorly, brown posteriorly, maximum width 1.00, length 3.00. Hemelytral membrane almost attaining tip of abdomen, venation not evident, membrane of underlapping wing (left) mostly pruinose. Hindwings well developed. Ventrally, prosternum with mid-ventral carina with shallow central channel, margins of channel with elongate golden hairs. Propleuron with extensive yellow glabrous area laterally extending 2/3 distance to mesal margin, brown pruinose mesad of yellow glabrous area, mesally with elongate recumbent hairs on occlusal surface with coxa; propleura widely separated at midline. Mesosternum with medial carina with dense brush of elongate golden-brown setae and series of 8 ventrally directed protuberances; meso- and metasterna mostly dark brown to black, pruinose.

Legs. All segments yellow brown except brown protarsus, meso- and metacoxae; profemur with scattered brown spots in posterior 1/2; anterior margin with dense pad of elongate, pale setae; protibia and tarsus with row of spatulate, pale setae at dorsal margin of flattened inner surface; single tarsal segment; claw minute; procoxa with patch of short, dark brown, peg-like setae on posterior surface; middle and hind coxae covered with short, pale, recumbent setae; metaxyphus with pronounced transverse and longitudinal carinae, thus resembling head of Phillips screwdriver directed posteroventrally; meso- and metafemora with posteroventral row of orange-brown, peg-like spines becoming obsolete proximally; spines strong on mesofemur, weak on metafemur; middle of posterior surface with row of short, pale setae; posterodorsal row of dark, peg-like spines. Meso- and metatibiae with rows of stout reddish-brown spines; 2 transverse rows of long stout spines at apex; long, golden brown swimming hairs. Mesotarsi missing, metatarsus with long, golden brown swimming hairs. Claws slender, curvature strongest apically, with basal tooth. Leg measurements as follows: foreleg, femur 2.48, tibia 1.86, tarsus 0.40; middle leg, femur 2.60, tibia 2.00; hind leg, femur 3.04, tibia 3.44, tarsomeres 1–3 0.24, 0.62, 0.64.

Abdomen. Connexiva III–VII exposed laterally beyond hemelytra, each yellow anteriorly, brown posteriorly; lateral margins smooth, with stout setae scattered on IV-VII; stout setae more dense on posterior segments and posteriorly within segments IV–VI; posterolateral angles of III–V square, VI slightly acuminate, VII moderately acuminate. Ventrally brown except narrow marginal glabrous band; glabrous band with segments II–VII each yellow anteriorly, brown posteriorly; sterna densely covered with short, pale, recumbent setae; mediosternites with elongate, erect, pale setae. Laterosternite glabrous areas ovate on II and VII, elongate and transverse on II–VI. Sterna III–IV with prominent midventral tubercle; tubercle digitate on III, rounded on IV. Mediosternites with midventral glabrous areas widening posteriorly from triangular on V, quadrate on VI, elongate covering middle 1/2 of subgenital plate (VII); glabrous area of subgenital plate yellow; long pale setae especially dense near margin of glabrous areas. Subgenital plate broad basally, gradually narrowing to elongate tongue-like lobe in distal 1/3; lobe with lateral margins reflexed dorsad; lateral margins of subgenital plate sinuate ( Fig. 56 ); strong lateral fringe of elongate golden brown setae at base of tongue-like lobe; subgenital plate length at midline 2.12, width at base 2.16.

Discussion. This is the type species of the genus as designated by Štys and Jansson (1988). We have been unable to locate the type specimen, which Montandon (1913) indicated was collected in “W. Usambara” ( Tanzania) and was the only example and deposited in “Deutsches Nat. Mus. Berlin.” This century-old name probably agrees best with the modern name of Museum für Naturkunde. In 1964, some insect specimens were transferred from the Museum für Naturkunde to the Senckenberg Deutsches Entomologisches Institut Müncheberg, formerly known as Deutsches Entomologisches Institut in Eberwalde in the 1960s and Deutsches Entomologisches National Museum in the early 1900s (S. Blank, J. Deckert, and H. Zettel, pers. com.). Unfortunately, the type is not in either of these German museums. Neither is it in the following museum collections: AMNH, BMNH, CMNH, DMSA, FMNH, HNHM, MCSN, MNB, MNHN, MNIN, NHMW, NMWC, RMCA, RMNH, SDEI, SEMC, SMNH, UMC, USNM.

Montandon (1913) did not indicate the sex of the holotype in the original description. In the Musée Royal de l'Afrique Centrale collection are two female specimens identified as N. usambaricus . Poisson (1948) examined both specimens and determined them to be conspecific. However, these clearly represent two distinct species based on subgenital plate and overall body shape. One specimen collected at Lac Albert, Ishwa, Congo agrees with our female N. vuga specimens, although a male would be needed for specific confirmation. The determination label for that specimen is of Poisson in 1945, but has been folded twice and pushed up the pin. The other specimen is from Tuevo ( French Congo) and was determined by Montandon in 1914. Although Montandon’s determination label ( Fig. 55 ) has old creases from being folded previously and was on the pin upside down and unfolded, we consider this specimen to be authentic N. usambaricus because it was determined by Montandon himself and agrees generally with the original description; but is slightly smaller (10.9 instead of 11.5 mm). Although Poisson (1948) referred to this specimen as a female cotype, it cannot be a cotype because there is no reference in Montandon’s (1913) original description to this specimen identified by Montandon in 1914. Thus, we here designate this female specimen as the neotype of N. usambaricus . A female identified as N. usambaricus from Congo in the Poisson acquisition in the Drake Collection at USNM generally agrees with the neotype, although it is substantially wider, measuring 11.2 by 7.6 mm. Because of the body proportion disparity, we are not assigning a specific identity to this USNM specimen, although we do not rule out the possibility that it is N. usambaricus .

Diagnosis. Although it is large, N. usambaricus is not in the group of distinctly large and ovate species. The pronotum is largely devoid of dark maculation. Currently, only the female is known and the subgenital plate is gently sinuate to the distal spatulate process ( Fig. 56 ).

Published records. [ TANZANIA]: W. Usambara, V. Benningsen ( Montandon 1913).

Material examined. NEOTYPE (here designated): [ DEMOCRATIC REPUBLIC OF CONGO]: Tuevo, 2- VIII-1911, R. Mayné / R. det., A, 202 / Neomacrocoris usambaricus 1913 Montandon, det Montandon 1914 ( RMCA, Ƥ).

Figures

FIGURES 54 – 56. Neomacrocoris usambaricus NEOTYPE (54) habitus, (55) specimen labels of neotype, (56) terminal abdominal sterna including subgenital plate. Sizes are not proportionate among figures.