Rhagovelia suloga, 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 : 151-155

Rhagovelia suloga new species

( Figs. 6 , 12, 13 , 209 , 240 , 253‒258 )

Type material examined. Holotype, wingless male: PAPUA NEW GUINEA, Milne Bay Prov., Woodlark Island, Suloga Peninsula, stream entering W. side of Suloga Harbor , 0–180 m., 9°12'22"S, 152°42'29"E, water temp. 27–28 °C., 23–24 January 2003, CL 7217b, rocky midreach, D. A. and J. T. Polhemus ( BPBM) . Paratypes: PAPUA NEW GUINEA, Milne Bay Prov., Woodlark Island : 10 winged males, 10 winged females, 206 wingless males, 144 wingless females, 40 immatures, same data as holotype ( USNM, BPBM) ; 5 wingless males, 3 wingless females, same data as preceding except 180 m., 9°12'13"S, 152°43'10"E, pools below seeps over bedrock, CL 7217c, D. A. and J. T. Polhemus ( USNM) ; 1 wingless male, same data as preceding except 5– 90 m., 9°12'12"S, 152°43'10"E, lower midreach, CL 7217a, D. A. and J. T. Polhemus ( USNM) ; 7 wingless males, 5 wingless females, 2 immatures, same data as preceding except 0– 5 m., 9°12'33"S, 152°43'32"E, swamp forest in terminal reach above estuary, CL 7218, D. A. and J. T. Polhemus ( USNM) ; 11 wingless males, 7 wingless females, 3 immatures, Suloga Peninsula, rocky stream entering NE side of Suloga Harbor, 0– 15 m., 9°11'19"S, 152°44'51"E, water temp. 26° C., 24 January 2003, 12:00–14:00 hrs., CL 7220, J. T. Polhemus ( USNM) .

Description

Wingless male: Size: Length = 3.20–3.50 mm (x = 3.34, n = 5); width = 1.10–1.20 mm (x = 1.12, n = 5). Wingless female, length = 3.20– 3.50 mm (x = 3.34, n = 5); width = 1.20–1.30 mm, (x = 1.23, n = 5). Winged male, length = 3.70–3.80 mm (x = 3.75, n = 2); width = 1.40 mm (x = 1.40, n = 2). Winged female, length = 3.55‒3.70 mm (x = 3.63, n = 3); width = 1.40–1.50 mm, (x = 1.43, n = 3).

Color: Dorsal ground color dark brown to black, marked with dark yellow on anterior pronotum and connexiva, basal antennae and legs ( Fig. 253 ). Head dark brown; rostrum, tylus and gula pale brown, rostrum piceous distally; eyes dark reddish black. Pronotum dark yellow on anterior one-third, dark brown on posterior two-thirds, the pale anterior coloration extending laterally and ventrally onto propleurae. Mesonotum chestnut brown, metanotum and abdominal tergites I–VI black, tergites VII–IX brown, tergites I–VI uniformly dull and lacking shining areas, tergites VII and VIII broadly shining centrally, connexiva black on inner halves, dark yellow on outer halves. Antennal segment I with basal one-third pale yellow, distal two-thirds plus all of segments II–IV brown. Legs generally brown, with coxae, trochanters, basal four-fifths of fore femur dorsally and ventrally, basal third of hind femur dorsally, and entirity of hind femur ventrally except extreme apex pale yellow. Venter dark brown, with mesosternum and abdominal ventrite VI orange-brown, acetabula pale whitish yellow, abdominal ventrites VII–IX yellowish brown.

Structural characters: head moderately short, declivant anteriorly, with weakly impressed median line; length 0.35, width 0.75; length of eye along inner margin 0.35, anterior/posterior interocular space, 0.25/0.40. Pronotum long, width 1.00, length along midline 0.70, greater than dorsal length of head, leaving mesonotum exposed only as a small crescent posterior to pronotum, lacking foveae. Mesonotum length at midline 0.08. Metanotum moderately exposed, length at midline 0.10. Lengths of abdominal tergites I–VIII, respectively: 0.15: 0.20: 0.17: 0.20: 0.20: 0.30: 0.40: 0.37. Connexiva of even width throughout, with margins nearly straight except very slightly bowed inward adjacent to abdominal tergites I–III, distal segments with margins evenly convergent posteriorly, posterolateral angles not modified, separated by entire width of tergite VIII.

Entire dorsum and laterotergites covered with fine, appressed pale pubescence; 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, anterior margins of all femora, anterior margin of hind tibia; scattered long, straight, slender, evenly spaced brown setae present along posterior margins of all femora and posterior margin of hind tibia; anterior margin of fore tibia with slender erect black setae plus a thick fringe of short, appressed gold setae; fore and middle trochanters lacking pegs or teeth; fore and middle femora and tibiae with margins straight, not flattened or otherwise modified; fore tibia very slightly expanded and ventrally flattened on distal one-fourth; hind trochanter bearing 3 small dark pegs ventrally; hind femur highly incrassate, bearing teeth ventrally in area covered by infolded hind tibia, these teeth arranged in a single longitudinal row on basal half of femur, splitting into two parallel rows on distal half, the single basal row consisting of approximately 10 tiny black pegs, the dorsal row distally consisting of 9 subequal, moderate-sized yellowish teeth with black apices, the third and sixth teeth in this series (counting basally to distally) slightly larger, the most distal teeth in this row gradually declining in size toward femoral apex, the ventral tooth row distally consisting of 6 small, subequally sized black teeth; hind tibia straight, inner surface bearing an irregular longitudinal row of 18–20 small dark teeth plus a single larger black spur near apex ( Figs. 255, 256 .

Venter of head and thorax lacking small black denticles; mesosternum slightly depressed centrally, margins of this depression bearing long, fine gold setae; metasternum ventrally convex, bearing erect, long gold setae; abdominal venter set with short appressed gold setae intermixed along longitudinal midline with longer, fine, erect gold setae; basal abdominal ventrites highly sculptured, ventrite I lying in vertical orientation, remaining ventrites horizontal and all in similar plane, ventrites II and III with an acute longitudinal carina of V-shaped cross section medially, this carina continuing in less pronounced form onto ventrites IV–V, ventrite VI unmodified, ventrite VII broadly and shallowly depressed centrally, ventrite IX with a low but sharp longitudinal median carina.

Male paramere small, bean-shaped, distal section angled slightly upward, bearing scattered short, stout setae, apex bluntly rounded ( Fig. 257 ). Male proctiger with basolateral lobes prominent and angular; distolateral lobes broadly rounded; distal cone with apex blunt, broadly rounded ( Fig. 258 ).

Lengths of antennal segments I–IV: 0.62: 0.42: 0.75: 0.50.

Lengths of leg segments as follows: femur, tibia, tarsal 1, tarsal 2 of fore leg, 0.95: 0.90: 0.02: 0.01: 0.25; of middle leg, 1.50: 1.10: 0.05: 0.45: 0.65; of hind leg, 1.45: 1.35: 0.05: 0.20: 0.30.

Wingless female: Similar to wingless male in general structure and coloration, with following exceptions: mesonotum black; abdominal tergites V–VIII brown and shining centrally; connexival margins strongly convergent posteriorly adjacent to abdominal tergites I–III, then nearly parallel with only slight posterior convergence adjacent to tergites IV–VIII, margins widely separated, not infolded, not covering lateral sections of any tergites, connexival margins of even width throughout, uniformly set with short setae, lacking thinned or glabrous sections ( Fig. 254 ); posterolateral connexival angles forming right angles, bearing bushy, moderately dense tufts of moderately long, posteriorly-directed black setae; abdominal tergite VIII flat, lying in horizontal orientation, proctiger deflected downward approximately 30° from vertical, lacking lateral setal tufts; hind femur only weakly incrassate, posterior margin bearing a small, acute black tooth at approximately two-thirds distance from base, followed by a large, spine-like brown tooth with a black tip, this followed by 3 smaller black teeth of steadily declining size toward femoral apex; hind tibia straight, inner surface lacking teeth or pegs; ventral coloration predominantly yellowish brown, with meso- and metasternum dark brown to varying degrees; all abdominal ventrites lying in similar horizontal plane, lacking raised setal tufts along longitudinal midlines except for a few golden setae centrally on ventrites I and II ( Fig. 209 ).

Winged male: Similar to wingless male in general structure and coloration, with following exceptions: pronotum greatly enlarged, width 1.40, length 1.25, completely covering meso- and metanotum, anterior margin dark yellow, this pale coloration divided by a narrow brown longitudinal midline stripe; humeri enlarged, slightly protrusive laterally; posterior pronotal lobe dark brown, broadly domed, lacking obvious foveae, posterior margin broadly angular, bearing scattered long, gently curving, semi-erect black setae; forewings uniformly dark blackish-brown, extending past apex of abdomen when intact, bearing 4 closed cells consisting of two elongate cells in basal half of wing followed by two smaller cells distally near center of wing, with the outer distal cell slightly smaller than the inner disal cell ( Fig. 12 ). Hind femur less incrassate than in wingelss male.

Winged female: Similar to winged male in general body form and coloration, pronotum width 1.45, length 1.20 ( Fig. 6 ).

Etymology. The name "suloga " is a noun in apposition and refers to the type locality, the Suloga Peninsula of Woodlark Island.

Distribution. Endemic to Woodlark Island ( Fig. 240 ). The species range as presently known occupies the Woodlark Island area of freshwater endemism (Area 40) as delineated by D. Polhemus & Allen (2007).

Discussion. Rhagovelia suloga is a member of the R. papuensis group endemic to Woodlark Island. Within the regional assemblage it may possibly be confused with R. bwagabwaga from Misima or R. guiagoila from Basilaki and Sideia islands, but may be separated from these species by the absence of raised gold setal tufts medially on the basal abdominal ventrites of the female, and by the structure of the male proctiger and parameres (compare Fig. 209 to Figs. 204, 207 ). Females of R. suloga also have the connexival margins parallel, versus posteriorly convergent in R. bwagabwaga (compare Figs. 235 , 254 ), and lack the fringe of thick black setae on the margins of the basal connexival segments seen in that latter species. Although the connexival margins are also parallel in R. guiagoila , that species has the abdomen narrower and more elongate, and lacks the curving tufts of setae at the posterolateral connexival angles (compare Figs. 254 , 275 ).

Ecological notes. Rhagovelia suloga was common on shaded pools and on the marginal eddies of rocky forest streams on Woodlark Island. The type series was taken from a clear, rocky, moderate-sized stream (CL 7217), which local people referred to as the Laiavakakain River, a name not shown on topographic maps. The stream drained from the hills on the west side of Suloga Harbor, a deep embayment running into the south coast of Woodlark Island, and had its headwaters near the highest elevations on the island. The substrate here consisted predominantly of metamorphic rocks and associated cobbles and gravels, with the latter in many areas overlying a basal substrate of orange clay. The stream profile was gradual in the midreach ( Fig. 259 ), with higher gradient boulder jams as one progressed upstream. Bedrock exposures were comparatively few, forming only a single small fall about 3 m tall in the midreach.

Additional specimens were also taken from a rocky stream entering the northeast side of Suloga Harbor (CL 7220). This latter stream flowed through a series of chutes and cascades in dark metamorphic rock, with a small tributary entering via a waterfall.

Figures

FIGS. 6–9. Rhagovelia species females from the EPCT region, dorsal views of fully winged morphs showing shapes of wings and expansion of pronotum. 6. R. suloga n. sp., specimen from Woodlark Island, CL 7217. 7. R. aviavi n. sp., specimen from Lakekamu River basin, New Guinea, CL 7156. 8. R. kolukolu n. sp., specimen from Tagula Island, CL 7194. 9. R. mimani n.sp., specimen from Dorobisoro, New Guinea, CL 7263.

FIGS. 12, 13. Rhagovelia suloga n. sp., wings; specimen from Woodlark Island, CL 7217. 12. Forewing, showing the presence of two distal closed cells of unequal size, with the outer cell much shorter than the inner, and in this case the incipient development of a third cell. 13. Hind wing.

FIGS. 209–211. Rhagovelia papuensis group, female ventral abdomen showing locations of depressions and patterns of setiferation. 209. Rhagovelia suloga n. sp.; specimen from Woodlark Is., Suloga Peninsula, CL 7217. 210. Rhagovelia ivimkana n. sp.; specimen from New Guinea, Tekadu, CL 7157. 211. Rhagovelia dinga n. sp.; specimen from New Guinea, Kamiali, CL 7243.

FIG. 240. Distributions of species in the R. yela subgroup in the Louisiade Islands, and R. suloga on Woodlark Island.

FIGS. 253–258. Rhagovelia suloga n. sp., structural details; specimens from Woodlark Is., stream on Suloga Peninsula, CL 7217. 253. Wingless male, dorsal habitus. 254. Wingless female, dorsal habitus. 255. Male right hind leg, posterior view. 256. Male right hind leg, dorsal view. 257. Male left paramere, outer lateral view. 258. Male proctiger, dorsal view.

FIGS. 203–208. Rhagovelia papuensis group, female ventral abdomen showing locations of depressions and patterns of setiferation. 203. Rhagovelia loriae n. sp.; specimen from New Guinea, Dorobisoro, CL 7260. 204. Rhagovelia guiagoila n. sp.; specimen from Basilaki Is., Kalawai River, CL 7294. 205. Rhagovelia basima n. sp.; specimen from Fergusson Is., Yaya River, CL 7178. 206. Rhagovelia elongata n. sp.; specimen from Goodenough Is., Matalamoia River, CL 7187. 207. Rhagovelia bwagabwaga n. sp.; specimen from Misima Is., Keyana Creek, CL 7206. 208. Rhagovelia priori n. sp.; specimen from New Guinea, Kofure River, CL 7304.

FIGS. 234–238. Rhagovelia bwagabwaga n. sp., structural details; specimens from Misima Is., Keyana Creek, CL 7206. 234. Wingless male, dorsal habitus. 235. Wingless female, dorsal habitus. 236. Male right hind leg, dorsal view. 237. Male left paramere, outer lateral view. 238. Male proctiger, dorsal view.

FIGS. 274–279. Rhagovelia guiagoila n. sp., structural details; specimens from the China Strait islands. 274. Wingless male, dorsal habitus. 275. Wingless female, dorsal habitus; 274 and 275 from Sideia Is., Kwabunamoa River, CL 7287. 276. Male right hind leg, posterior view. 277. Male right hind leg, dorsal view; 278. Male left paramere, outer lateral view. 279. Male proctiger, dorsal view; 276–279 from Basilaki Is., Kalawai River, CL 7294.

FIG. 259. Stream entering Suloga Harbor, Woodlark Is., Milne Bay Province, Papua New Guinea, CL 7217, type-locality for R. suloga n. sp.