Rhagovelia antap, Polhemus, 2024

Polhemus, Dan A., 2024, Thirty-four new species of Rhagovelia (Heteroptera: Veliidae) from the East Papua Composite Terrane, far eastern New Guinea, Zootaxa 5400 (1), pp. 1-214 : 41-45

Rhagovelia antap new species

( Figs. 63–69 , 84 )

Type material examined. Holotype, wingless male, PAPUA NEW GUINEA, Milne Bay Prov., New Guinea, Cloudy Mountains, headwater tributary to upper Watuti River , S. of Gelemalaia , 715 m., 10°29'50"S, 150°13'58"E, water temp. 22° C., 10 April 2002, 16:00–17:30 hrs., CL 7175, D. A. Polhemus ( USNM) . Paratypes: PAPUA NEW GUINEA, Milne Bay Prov., New Guinea: 1 winged male, 4 wingless males, 3 wingless females, same data as holotype, D. A. Polhemus ( USNM, BPBM). Central Prov., New Guinea: 1 winged female, 1 wingless male, 2 wingless females, Owen Stanley Range , trib. to upper Mimani River , 2.7 km. NE of Dorobisoro, 580–685 m., water temp. 21.5 °C., 8 October 2003, 09:30–12:30 hrs., 9°27'23"S, 147°57'03"E, CL 7262, D. A. Polhemus ( USNM BPBM) .

Description.

Wingless male. Size: Length = 4.00– 4.50 mm (x = 4.30, n = 3); width = 1.30–1.60 mm (x = 1.48, n = 3). Wingless female, length = 4.30–4.50 mm (x = 4.36, n = 4); width = 1.50–1.60 mm, (x = 1.57, n = 4). Winged male, length = 5.00 mm (n = 1); width = 1.80 mm (n = 1). Winged female, length = 5.40 mm (n = 1); width = 2.10 mm (n = 1).

Coloration: Dorsal ground color orange-brown, marked with black on dorsal head, thorax and abdomen ( Fig. 63 ). Head orange-brown except vertex dark brown; tylus, genae and rostrum all orange-brown, rostrum fuscous ventromedially, piceous distally; eyes dark reddish black. Pronotum orange-brown, posterior half and narrowly along margins of propleurae dark brown to black. Mesonotum entirely orange-brown. Metanotum entirely black. Abdominal tergites I–III dark brownish-black with small, vaguely suggested orange-brown patches centrally, tergites IV and V dark brownish-black laterally with large orange-brown patches centrally, tergites VI and VII predominantly orange-brown with narrow brownish black markings along lateral and posterior margins, tergite VIII black, tergites I–VI uniformly dull and lacking shining areas, tergite VII dull anteriorly, semi-shining posteriorly, tergite VIII entirely semi-shining; connexiva dark brown on inner halves, orange-brown on outer halves, ventral faces dark yellow. Antennal segment I yellowish brown on basal one-third, orange-brown on middle one-third, medium brown on distal one-third, segments II–IV entirely black. Legs generally orange-brown, with all tibiae medium brown, all coxae dark brown. Venter orange-brown except areas surrounding spiracles on paratergites and all of abdominal ventrite VIII dark brown.

Structural characters: Head moderately short, declivant anteriorly, with weakly impressed median line; length 0.55, width 0.95; length of eye along inner margin 0.45, anterior/posterior interocular space, 0.25/0.50. Pronotum short, length along midline 0.50, less than dorsal length of head, leaving mesonotum broadly exposed, width 1.50; mesonotum smooth, lacking deep foveae, humeri depressed, length 0.70. Metanotum barely exposed, length 0.20. Lengths of abdominal tergites I–VIII, respectively: 0.25: 0.25: 0.30: 0.25: 0.25: 0.30: 0.50: 0.30. Connexiva with margins of even width throughout, weakly sinuate, being gently inwardly concave adjacent to abdominal tergites I–III, then gently outwardly convex adjacent to tergites IV and V, then gradually convergent posteriorly adjacent to tergites VI and VII; posterolateral angles not modified, separated by entire width of tergite VIII.

Entire dorsum and laterotergites covered with fine appressed golden pubescence, intermixed with a few scattered longer, semi-erect black setae centrally on posterior margins of metanotum and abdominal tergites I and II; legs and antennae thickly clothed with short appressed gold setae, with scattered long, erect, spine-like black setae on anterodorsal faces of antennal segments I and II, and anterior margins of all femora, long, slender, dark setae along posterior margins of fore and hind femora, numerous long, pilose brown setae along posterior margin of hind femur; fore and middle trochanters lacking pegs or teeth; fore and middle femora and middle tibia with margins straight, not flattened or otherwise modified; fore tibia slightly expanded and ventrally flattened on distal one-fourth, hind trochanter bearing 12 small dark peg-like teeth ventrally; hind femur highly incrassate, bearing numerous pegs and teeth of varying sizes scattered across ventral face, the most dorsal row consisting of a moderately large orange-brown tooth with a black tip lying about two-thirds distance distally from the femoral base, followed by 5 similarly formed and colored teeth of progressively decreasing size distally, next row ventrally consisting of approximately 15 tiny, closely appressed black pegs basally, followed by a relatively large orange-brown tooth with a black apex about one-third the distal distance from the femoral base, next row ventral to this consisting of 10 orange-brown teeth with dark tips beginning at one-quarter the distance from the femoral base and running distally to the apex, these teeth small basally, becoming progressively larger distally, last tooth row ventrally consisting of 8 small dark teeth forming an irregular line when viewed ventrally, followed by a single larger tooth at two-thirds distance from femoral base; hind tibia broadly and gently sinuate, inner surface bearing 2 parallel rows of 14 small, blunt, dark teeth, followed distally by a large, acute, orange-brown tooth with a dark apex slightly over one-half the distance from the base, followed by 6 similar but smaller stout, sharp dark teeth running to distal tibial apex ( Figs. 65, 66 ).

Venter of head and thorax lacking small black denticles; mesosternum slightly depressed centrally, margins of this depression bearing very long, fine gold setae; metasternum gently tumid centrally, bearing curling gold setae posteromedially, lateral sections weakly depressed; abdominal venter set with short appressed gold setae intermixed with scattered long, fine, erect gold setae along longitudinal midline of ventrite I; basal abdominal ventrites highly sculptured, ventrite I lying in vertical orientation, remaining ventrites horizontal and all in similar plane, ventrite II with a strongly raised carina along longitudinal midline, this carina continuing in less pronounced form onto ventrites III and IV, ventrites V and VI unmodified, ventrite VII broadly and shallowly flattened centrally, ventrite VIII weakly depressed laterally to either side of raised midline.

Male paramere thick, elongate, slightly sinuate, bearing stout setae along basal two-thirds of ventral margin, dorsal margin with a sharp notch between the basal and distal lobes, posterior apex truncate ( Fig. 67 ). Male proctiger with basolateral lobes well developed, broadly angular; distolateral lobes weakly developed, gently rounded; distal cone triangular, apex acute ( Fig. 68 )

Lengths of antennal segments I–IV: 1.25: 0.75: 1.05: 0.75.

Lengths of leg segments as follows: femur, tibia, tarsal 1, tarsal 2 of fore leg, 1.60: 1:55: 0.06: 0.03: 0.45; of middle leg, 2.50: 1.90: 0.10: 0.70: 1.00; of hind leg, 2.65: 2.70: 0.07: 0.20: 0.45.

Wingless female: Similar to wingless male in general structure and coloration, with following exceptions: all abdominal tergites orange-brown centrally, dark brown laterally, tergites I–IV dull, tergites V–VIII semi-shining centrally; connexival margins straight, of even width throughout, converging evenly to posterior apex of abdomen ( Fig. 64 ), posterolateral angles broadly rounded when viewed laterally, bearing small, tapering tufts of posteriorly-directed black setae, apices not infolded, separated by entire width of abdominal tergite VII; abdominal tergite VIII and proctiger angling downward at approximately 40° when viewed laterally; hind femora only weakly incrassate, bearing a moderately large, sharp, distally-angled orange-brown tooth with a black apex at about two-thirds distal distance from base, followed distally by 5 much smaller sharp, black teeth; hind tibiae straight, inner surface lacking teeth; ventral coloration almost entirely orange-brown except for limited dark markings along acetabular sutures; abdominal sternite II with longitudinal medial carina on basal two-thirds only, remaining abdominal ventrites unmodified.

Winged male: Similar to wingless male in general structure and coloration, with following exceptions: pronotum greatly enlarged, completely covering meso- and metanotum, width 1.80, length 1.60; humeri enlarged, posterior apex angular, anterior margin broadly dark yellow across entire width, central section broadly medium brown, posterior margin narrowly paler brown, posterior lobe set with scattered shallow foveae immediately adjacent to posterior margin, entire pronotum covered with short recumbent gold setae, intermixed on posterior lobe with moderate length, straight, stiff, dark setae along posterior margin; forewings uniformly dark brown, bearing 4 closed cells extending into distal section of wing, consisting of two long cells in the basal half of the wing plus two smaller cells of subequal size distally. Male hind femur only moderately incrassate, bearing 2 rows of teeth ventrally, the dorsal row consisting of a large, sharp, orange-brown tooth with a black apex at about two-thirds distal distance from femoral base, followed by 4 similar but much smaller teeth of progressively decreasing size to distal apex, the ventral row of teeth more irregular, consisting of ~16 very small black teeth running the length of the femur, intermixed with 3 slightly larger orange-brown teeth with black apices on central section of femoral margin.

Winged female: Similar to winged male in general form and coloration, but body size larger; pronotum width 2.00, length 1.90.

Etymology. The name “antap ” is derived from the Papuan pidgin English word for “on top,” and refers to the occurrence of this species only at high elevation spring sources.

Distribution. Southeastern New Guinea; endemic to the Papuan Peninsula ( Fig. 84 ). The species range as presently known occupies the South Papuan Peninsula Foreland and Cloudy Mountains areas of freshwater endemism (Areas 30 and 34) as delineated by D. Polhemus & Allen (2007).

Discussion. Rhagovelia antap is a large, uniformly orange-brown species found as localized populations at upland springs forming the outflow sources for first order streams. The species is easily recognized by its large size, predominantly orange-brown coloration, heavily armed male hind leg ( Figs. 65, 66 ), and distinctively massive and truncate male paramere ( Fig. 67 ). Antennal segment III is also unusually long in this species, with the ratio of its length to that of either antennal segment II or segment IV being 1.05/0.75.

The other Rhagovelia species known from the EPCT with which R. antap might possibly be confused include R. aureospicata , which is also large and orange-colored but possesses a set of thorn-like spines basally on the male middle femur ( Fig. 333 ), a broader and more posteriorly rounded female abdomen (compare Figs. 64 and 332 ), and different male genitalic structures ( Figs. 67, 68 to Figs. 335, 336 ); or R. udabe and R. goilala , which are also large upland species but have much darker dorsal coloration ( Figs. 70, 71 , 77, 78 ) and differently shaped male parameres ( Figs. 74 , 81 ).

Ecological notes. The type-series of R. antap was taken from a spring at the source of a first order tributary streamlet near the crest of the northern ridge of the main Cloudy Mountain massif, lying south of the Sagarai River, which in turn drains eastward into Orangerie Bay. The insects were only found in the immediate vicinty of the source spring, which lay at the base of a set of wet bedrock faces. The stream profile descended steeply from here through a set of small waterfalls, rapids and flowing pools, with the entire area heavily shaded by relatively intact upland rain forest, in which just a few trees had been removed for local construction of shelters from the frequent rain showers at this elevation.

A second series of R. antap was taken along a tributary to the upper Mimani River (CL 7262) in the Kemp Welch River basin, from springs at the source of a clear, rocky, heavily shaded creek descending steeply through primary rain forest, in a bed of mixed rock types including pyroclastics, quartz, and greenschist. This stream was followed upward along a steadily steeper profile, until a bedrock sill was encountered at 670 m elevation, followed soon thereafter by a series of waterfalls. Individuals of R. antap were found only in the extreme headwater reach above these falls at a headwater spring ( Fig. 69 ), whereas the reaches below the falls supported R. mimani and R. obscura .

Figures

FIG 69. A spring emerging from bedrock at the head of a tributary to the Mimani River, east of Dorobisoro, Central Prov., Papua New Guinea, CL 7262, habitat for R. antap n. sp.

FIGS. 63–68. Rhagovelia antap n. sp., structural details; specimens from New Guinea, Cloudy Mountains, CL 7175. 63. Wingless male, dorsal habitus. 64. Wingless female, dorsal habitus. 65. Male right hind leg, posterior view. 66. Male right hind leg, dorsal view. 67. Male left paramere, outer lateral view. 68. Male proctiger, dorsal view.

FIG. 84. Distributions of species in the R. goilala subgroup in eastern New Guinea.

FIGS. 331–336. Rhagovelia aureospicata n. sp., structural details; specimens from New Guinea, Wau, upper Namie Creek, CL 1829. 331. Wingless male, dorsal habitus. 332. Wingless female, dorsal habitus. 333. Male middle femur, ventral view, showing set of stout spines basally. 334. Male left hind femur, dorsal view. 335. Male left paramere, outer lateral view. 336. Male proctiger, dorsal view.

FIGS. 70–75. Rhagovelia udabe n. sp., structural details; specimens from New Guinea, Woitape, CL 7252. 70. Wingless male, dorsal habitus. 71. Wingless female, dorsal habitus. 72. Male right hind leg, posterior view. 73. Male right hind leg, dorsal view. 74. Male left paramere, outer lateral view. 75. Male proctiger, dorsal view.

FIGS. 77–82. Rhagovelia goilala n. sp., structural details; specimens from New Guinea, Fane, CL 7256. 77. Wingless male, dorsal habitus. 78. Wingless female, dorsal habitus. 79. Male right hind leg, posterior view. 80. Male right hind leg, dorsal view. 81. Male left paramere, outer lateral view. 82. Male proctiger, dorsal view.