Rhagovelia abbreviata, Zettel & Laciny & Freitag, 2020

Zettel, Herbert, Laciny, Alice & Freitag, Hendrik, 2020, Review of the genus Rhagovelia Mayr, 1865 (Insecta: Heteroptera: Veliidae) in the Palawan biogeographic region, the Philippines, Raffles Bulletin of Zoology 68, pp. 810-837 : 820-821

Rhagovelia abbreviata , new species

( Figs. 3C–F , 7E , 8B , 9C–E , 10D–F , 11C , 14A–C )

Etymology. The species epithet means “shortened” and refers to the peculiar shape of the female’s abdomen.

Type material. Holotype (apterous male; NMNH) labelled “PHIL: Palawan, Roxas, Bagong Bayan, creek downstream of Ilian Falls , 10°25′40″N 119°33′25″E, ca. 50 m, 17.XI.1995, leg. J. Mendoza (# 129)” . Paratypes (in ADMU, NHMW, UPLB, PNM, PCSD): 22 apterous males, 8 macropterous males, 9 apterous females, 5 macropterous females collected from the same locality (partly labelled “ Bagong Bayan Falls ”); 1 apterous male, 1 apterous female from northern Palawan, El Nido, New Ibahay, mountain creek in disturbed primary forest, ca. 150 m a.s.l. , 11°13′06″N, 119°29′32″E; 5 apterous males, 3 apterous females from northern Palawan, 20 km N Taytay, Pularaquin, Canequi Falls , 10°56′59″N, 119°28′09″E, 25 m a.s.l.

Type locality. Northern Palawan, Roxas municipality, barangay Bagong Bayan, Ilian Falls , 10°25′40″N, 119°33′25″E, 40 m a.s.l.

Diagnosis. Small, body stout, length of male 2.00– 2.13 mm (apterous), 2.14–2.27 mm (macropterous), female 1.92–2.19 mm (apterous), 2.31–2.41 mm (macropterous). Mesocoxa, base of mesotrochanter, and base of metafemur yellow. Body without spike-like setae. Male: Sternites 3–6 with sharp median carinae. Sternite 7 with indistinct paired impressions, a median carina only indicated. Segment 8 ventrally convex. Paramere short, U-shaped, but apex protruded ( Fig. 7E ). Apterous and macropterous females: Mesofemur with a short depression at ¾ 5 of length, at this position ventrally with a tuft of long setae. Apterous female: Abdomen ( Fig. 10D, E ) strongly shortened, shorter than wide. Connexiva bearing brushes of black setae at segments 5 and 7. Tergite 6 very short; laterotergite 6 absent; sternite 6 laterally reduced. Apex of abdomen starting from segment 7 directed dorsally, in two females from Pularaquin more posterodorsally. Tergite 8 with long black pilosity posteromedially.

Description of apterous male. Measurements of holotype: Body length 2.00; maximum body width (at metapleura) 0.88. Head length 0.30, width 0.63; minimum eye distance 0.17. Pronotum length 0.22, width 0.72. Lengths of antennomeres: I 0.51, II 0.28, III 0.40, IV 0.32. Lengths of leg segments: profemur 0.66, protibia 0.70, protarsus 0.02 + 0.02 + 0.16, mesofemur 1.09, mesotibia 0.94, mesotarsus 0.07 + 0.38 + 0.38, metafemur 0.78, metatibia 0.84, metatarsus 0.04 + 0.04 + 0.21.

Measurements of paratypes (n = 10): Body length 2.02–2.13; maximum body width (at metapleura) 0.81–0.88. Head width 0.61–0.64. Pronotum length 0.19–0.23, width 0.67–0.70.

Colour: Black. Pronotum with transverse orange mark in centre, laterally reaching level of medial eye margin. Basal half of antennomere 1, distal corner of proepisternum, all acetabula, coxae, and trochanters (mesotrochanter with distal black ring), basal half of profemur, and basal fifth to third of metafemur yellow. Rostrum and juga yellowish to dark brown. Middle of sternite 7 and segment 8 ventrally yellowish brown.

Pilosity: Sides of pronotum, propleuron, and mesopleuron with comparatively short setae. Thorax dorsally with short greyish pilosity. Abdominal tergites in addition to short appressed pilosity with slightly longer, subdecumbent black setae. Entire body without short spike-like setae.

Structures: Head slightly broader than anterior margin of pronotum. Juga flat, inclined, and relatively narrow, without spinulae. Pronotum very short, along midline about 0.7 times as long as head. Mesonotum along midline about 2.5 times as long as pronotum. Proepisterna bearing numerous small black spinulae anteriorly and mesally.

Profemur on extensor side with shallow concavity. Meso- and metacoxa and metatrochanter with numerous small black spinulae. Hindleg polymorphic: strong legs with moderately enlarged femora and strongly curved tibia; slender legs with rather slender femora and almost straight tibia. Stout femora suddenly narrowed at distal third, basal row with 2–7 small spines, large basal tooth of posterodistal row at first third of femur length followed by 3–5 shorter teeth. Slender femora more evenly narrowed distally, basal row with 3–6 small spines, posterodistal row consisting of 3–6 teeth. Anterodistal row with fewer and much shorter teeth than posterodistal row. Metatibia with variable dentition at flexor side.

Laterotergites horizontal. Tergite 7 about 2.0 times as long as tergite 6, and 0.7 times as long as broad. Abdominal venter with sharp median carina at sternites 3–6. Sternite 7 with indistinct paired impressions, a median carina only indicated. Segment 8 ventrally convex. Proctiger slender, lateral wings weakly developed ( Fig. 8B ). Paramere short, U-shaped, but apex slightly protruded ( Fig. 7E ).

Description of apterous female. Measurements of paratypes (n = 10): Body length 1.92–2.19; maximum body width (at metapleura) 0.97–1.02. Head width 0.66–0.69. Pronotum length 0.22–0.25, width 0.69–0.75.

Colour: As in male, except propleuron with yellow patch.

Pilosity: Pronotum laterally with long black setae. Mesofemur with normal pilosity, except for a ventral (anterior) patch of long setae in the depression. Mesonotum and tergites 1–7 without pilosity; tergite 8 with stiff, posteriorly-directed black setae. Laterotergites with fine pilosity laterally; connexiva bearing brushes of short black setae at segments 5 and 7. Gonocoxae and proctiger with fine short pilosity only.

Structures: Body slightly broader than in male; abdomen strongly abbreviated. Head distinctly broader than anterior margin of pronotum. Pronotum short, along midline about 0.8 times as long as head. Mesonotum along midline about 3 times as long as pronotum. Mesonotum posteriorly depressed; hind margin straight.

Mesofemur distally flattened, at ¾ 5 of length with unusual short depression (as if squeezed by forceps). Metafemur slender, without basal row of teeth, posterodistal row consisting of 1–3 teeth. Anterodistal row long consisting of minute, between pilosity hardly discernible spinules. Metatibia toothless, straight.

Abdomen ovoid in dorsal aspect. Connexival margins convex, strongly convergent until segment 5, segment 6 not visible in dorsal aspect. Segments 7 and 8 directed straight dorsad. Tergites 1–6 short, visible as narrow stripes; tergite 7 about 3 times as wide as long; tergite 8 largest. Sternite 6 normal at ventral part, laterally strongly narrowed towards connexival margins, and there hidden between sternites 5 and 7. Sternite 7 large, slightly flattened at middle. Gonocoxa large, evenly convex. Proctiger small, narrower than long.

Description of macropterous male. Measurements of paratypes (n = 8): Body length 2.14–2.27; maximum body width (at pronotum) 1.00–1.03. Head width 0.61–0.64. Pronotum length 1.00–1.09.

Colour: As in apterous male. Forewings black, without pale streak.

Pilosity: Apex of pronotal lobe with some long, posteriorly directed black setae. Basal veins of forewing with long black pilosity.

Structures: Pronotum large, with protruding humeri. Forewing with 3 or 4 closed cells, in dealate specimens broken at level of segment 6. Metafemur slender when compared to apterous male. Metatibia straight or weakly curved. In dealate specimens, tergite 7 visible, which is shiny in middle.

Description of macropterous female. Measurements of paratypes (n = 5): Body length 2.31–2.41; maximum body width (at pronotum) 1.09–1.13. Head width 0.66–0.67. Pronotum length 1.13–1.16.

Colour: As in apterous female. Forewings black, without pale streak.

Pilosity: Setae on pronotum and forewings as in macropterous male. Sternites 5–7 at connexival margins with long, posteriorly directed setae, most prominently developed on sternite 7.

Structures: Strongly deviating from apterous female by a moderately shortened abdomen. Pronotum large, with protruding humeri. Forewing as in male. Hindleg slightly slenderer than in apterous female. Abdomen “normal”, directed straight caudad. Sternite 7 about twice as long as sternite 6.

Comparative notes. The apterous female of R. abbreviata , new species, characterised by the shortened and posteriorly upright abdomen, is unique among all species in Southeast Asia, but a similar abdominal morphology is observed in some distantly related species from Madagascar ( Polhemus & Andersen, 2010). The structure of the female’s mesofemur, which bears a distinct depression and tuft of setae, is also exceptional and a valuable character for recognition of winged females. Characters of the male (carinate sternites, paramere with slightly protruded apex) suggest a close relationship with R. estrella . These two species differ from other Philippine species of the R. sarawakensis group by the absence of black spike-like setae on the abdomen.

Figures

Fig. 3. Habitus of Rhagovelia species. R. estrella: A, apterous male; B, apterous female. R. abbreviata, new species: C, apterous male; D, macropterous dealate, male; E, apterous female; F, macropterous female.

Fig. 7. Left parameres of Rhagovelia species, lateral view. A, R. minutissima; B, R. palawanensis; C, R. matillanoi, new species; D, R. estrella; E, R. abbreviata, new species; F, R. lansburyi; G, R. kawakamii hoberlandti; H, R. gapudi, new species.

Fig. 8. Proctiger of Rhagovelia species, dorsal view pilosity omitted. A, R. matillanoi, new species; B, R. abbreviata, new species; C, R. lansburyi; D, R. kawakamii hoberlandti; E, R. gapudi, new species.

Fig. 9. Hindlegs of Rhagovelia species, showing characteristic armatures pilosity omitted. A, R. matillanoi, new species, apterous male; B, R. matillanoi, new species, apterous female; C, R. abbreviata, new species, apterous male; D, R. abbreviata, new species, macropterous male; E, R. abbreviata, new species, apterous female; F, G, R. gapudi, new species, apterous males, two morphs; H, R. gapudi, new species, apterous female.

Fig. 10. Abdominal terminalia of females of Rhagovelia species, pilosity partly omitted. A–C, R. matillanoi, new species, arrow in A pointing to characteristic setae; D–F, R. abbreviata, new species; G–I, R. gapudi, new species, arrows in H, I pointing to concave ventral outline of gonocoxa. A, D, G, apterous specimen, dorsal aspect; B, E, H, apterous specimen, lateral aspect; C, F, I, macropterous specimen in 48 dealate, lateral aspect.

Fig. 11. Area and distribution maps of Rhagovelia species. A, overview of the Palawan Region with major islands and towns, insert showing the location of the area within the Philippines as well as the northern part of Borneo belonging to Malaysia; B, allopatric distribution of the species of the R. sarawakensis group related with R. minutissima; C, allopatric distribution of the species of the R. sarawakensis group related with R. estrella; D, distribution of R. lansburyi; E, distribution of R. kawakamii hoberlandti; F, distribution of R. gapudi, new species.

Fig. 14. Habitats. A, the stream below the Ilian Falls northeast of Roxas, running through a forested watershed area, is the type locality of R. matillanoi, new species, and R. abbreviata, new species; R. kawakamii hoberlandti was also found in quiet bays. B, C, the same three species were collected in the stream below the Canequi Falls at Pularaquin, about 20 km north of Taytay.