Phaenacantha nigrispina, Hartung, 2019

Hartung, Viktor, 2019, New Oriental and Australasian taxa of Colobathristidae (Hemiptera: Heteroptera) in the collection of the State Natural History Museum Stuttgart, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 59 (2), pp. 403-422 : 408-411

Phaenacantha nigrispina sp. nov.

( Figs 12–22 , 37–38 , 43–44 , 48 )

Type material. HOLOTYPE: J ( SMNS), collection number SMNS _ HET_ T 00002: “BORNEO: SABAH / Kinabalu N. P.: Poring / 500m, 29.XI.-2.XII.1996 / leg. W. SCHAWALLER [printed in black ink on yellow label]”. Specimen glued to a card, pygophore with genitalia (left paramere separated) dissected and stored in a plastic vial with glycerol attached to the same pin.Terminal flagellomere on right antenna broken, the detached part glued to the same card with the specimen . PARATYPES: 1 ♀ ( SMNS) ( Figs 20–22 , 48 ), collection number SMNS _HET_ T 00003: same collection data as the holotype. Intact specimen, glued to a triangle. 1 J ( SMNS), collection number SMNS _HET_ T 00004: same collection data as the holotype. Glued to a card; terminal flagellomere absent, left front terminal tarsomere detached and glued to the same card as the specimen; VII abdominal segment slightly damaged (genitalia intact).

Differential diagnosis. Characters demonstrating the affiliation to the nominotypical subgenus of the genus Phaenacantha are the same as in the case of P. grimmae . The completely black scutellar spine is a unique character within the genus and discerns this species from all others. Also as in P. grimmae , all three parts of pronotum are black, a rare character which immediately separates the two species from many others in the genus, including all described after HORVÁTH (1904) published his key to the genus. According to this key, the only species that seems to be close to P. nigrispina is P. biroi (they share the dark colouring of all parts of the pronotum and of the femora that, according to HORVÁTH (1904), are black in P. biroi but are dark brown in P. nigrispina ). Phaenacantha biroi is easy to discern from P. nigrispina by the structure of the genitalia ( GHAURI 1968), for example, the paramere with a posteriordorsal process in P. nigrispina and without such in P. biroi , the much more slender overall design of the paramere in P. biroi ; parandria much more slender in P. nigrispina and directed dorsoanteromediad whereas in P. biroi each parandrium is directed laterad. Additional characters include the pronotum less elevated above the head in P. nigrispina than in P. biroi (compare the Fig. 15 in the present paper with the Fig. 1 from GHAURI 1968); distance between an ocellus and an eye is at least 4 times the distance between ocelli in P. biroi and 5–6 in P. nigrispina (although, as ŠTYS 1974 indicated in his note on P. pallida (Stål, 1870) , this character is not very reliable in species with ocelli set very close to each other); third antennal segment twice as long as the first in P. biroi and longer than the first, but not so long in P. nigrispina ; fourth segment is longer than the third in P. nigrispina and shorter than the third in P. biroi (characters assessed after GHAURI 1968).

The species differs from P. grimmae in many genitalic features: male terminalia little more protruding in P. grimmae (segment VIII clearly visible in lateral view, Fig. 8 ) than in P. nigrispina (segment VIII hardly visible in lateral view, Fig. 18 ); pilosity of pygophore long in P. nigrispina ( Fig. 43 ) and short in P. grimmae ( Fig. 41 ); hypandrium with well-developed parandria directed dorsoanteriad in P. nigrispina ( Figs 37–38 , 43 ) and without pronounced parandria in P. grimmae ( Figs 35–36 , 41 ); paramere much more slender in P. grimmae ( Fig. 42 ) than in P. nigrispina ( Fig. 44 ); posterior process of paramere directed posteriad in P. grimmae ( Figs 36 , 41 ) and dorsomedioanteriad in P. nigrispina ( Figs 38 , 43 ); female sternite VII with broad median incision in P. grimmae ( Fig. 47 ) and without such an incision in P. nigrispina ( Fig. 48 ); valvula I longer and with lighter coloured median margin in P. grimmae ( Fig. 11 ), shorter and of uniform dark brown colour in P. nigrispina ( Fig. 22 ); valvula II inconspicuous in unprepared specimens in P. grimmae ( Fig. 11 ) and clearly visible in P. nigrispina ( Fig. 22 ); valvifer II thinner, longer and uniformly brown in P. grimmae ( Fig. 11 ) and shorter, broader and with lighter brown-coloured region bordering tergite IX in P. nigrispina ( Fig. 22 ). Somatic characters separating the two species include the femora (dark brown in P. nigrispina and testaceous in P. grimmae , Figs 1 and 12 ), the posterior lobe of the pronotum (more highly elevated in P. nigrispina than in P. grimmae , Figs 4 and 15 ), the hind pronotal margin (completely black or dark brown in P. grimmae , and much paler in P. nigrispina , Figs 3 and 14 ); the hind margin of scutellum and the base of the scutellar spine (yellowish in P. grimmae , black in P. nigrispina , Figs 3 and 14 ).

Description. Male. Coloration. Head ( Fig. 14 ) largely dark brown to black, except for two broad yellowish-brown stripes starting thin on each side at ocellus and becoming broader anteriorly, reaching anteromedial margin of eye and antennal socket and fusing with the yellowish-brown region at the base and sides of clypeus anteromedially; also parts of genae immediately ventrad and anteriad from eyes yellowish-brown. Ocelli red, eyes brown; labium brown ( Fig. 15 ), with tips of segments I to III paler and tip of terminal segment black; antennae and legs brown ( Figs 12–13 ), first antennomeres and femora darker than more distal parts; terminal tarsomeres concolorous with more proximal ones; thorax almost completely black to purplish black (including scutellar spine), except hind margin of pronotum (brown to transparently whitish) ( Fig. 14 ), posterior halves of fore and middle supracoxal lobes as well as hind supracoxal lobes and metepimera yellowish brown, peritreme of metathoracic gland dark brown ( Fig. 15 ); fore wings brown at the very base ( Fig. 14 ) with yellowish-brown veins on corium and clavus (somewhat darker on clavus and posterior margin of corium), regions between the veins transparent on corium and clavus and with brownish hue in membrane, and the veins (developed as folds) brown and with the immediate borders whitish; hind wings almost completely transparent except the divergence point of R and M brown and the membrane brownish as in the fore wing; abdominal sternites ( Fig. 13 ) dark brown, tergites dark brown in the middle and reddish-brown on lateral margins (tergites I and II almost black); segments III and IV slightly paler (sternite IV in the female paratype with large yellow spot in the middle) and abdominal gland orifices (between segments III/IV, IV/V and V/VI) paler brown ( Fig. 17 ); connexivum yellow except segments II (concolorous with the rest of the segment) and VII yellowish only anteriorly, but for the most part concolorous with rest of the segment ( Figs 17–18, 20–21 ); pygophore and segment VIII dark brown ( Fig. 19 ).

Vestiture and texture. Head (except two symmetrical depressions posterolaterally of ocelli), pronotal collar and middle lobe as well as propleura and prosternum covered with short silvery setae ( Fig. 14 ), relatively sparse on head and dense on forementioned parts of pronotum. Pronotum punctate; punctures on posterior lobe of pronotum larger than on middle lobe and each with short seta on the bottom, with regions between punctures glabrous and shiny. Punctation and vestiture of scutellum similar to that. Meso- and metapleura and sterna ( Fig. 15 ) as densely punctate as posterior pronotal lobe, with as little vestiture, but not shiny due to mycoid microsculpture typical of evaporatoria. Other body regions except wings with short adhering light-coloured setae easily visible on dark background but merging with it, e.g., on yellowish connexivum ( Figs 17–22 ). Tibiae also with short slender spines, more numerous distally and almost absent proximally ( Fig. 16 ).

Structure. Head ( Figs 14–15 ) with a median sulcus starting anteriad of the ocelli and reaching middle of vertex. The sulcus with a slim row of setae anteromedially not reaching posterior end of sulcus. Two other symmetrical depressions on each side of head, with the hind margin sinuate and building a sharp edge and with anterolateral slope smooth. Two symmetrical ridges starting at each ocellus, running parallel anteriad on both sides of sulcus, diverging, and almost reaching respective antennal socket where meeting another ridge coming from anteromedial eye margin and ending at clypeus. Area of vertex bordered by the ridges flat or even slightly concave. Eyes substylate. Angle between gula and clypeus sharp, gula oblique ( Fig. 15 ). Labium reaching middle coxae. Antennae thin, longer than body, most segments (especially I and IV) slightly to moderately curved ( Figs 12–13 ). Collar the lowest and the thinnest part of pronotum ( Fig. 14 ). Middle lobe with convex lateral outline, broader than collar; posterior lobe with a weakly sinuate lateral outline, broader than middle lobe. Middle and posterior lobe not quite in the same plane (posterior lobe convex in dorsal outline, middle one straight), separated by a shallow transverse impression ( Fig. 15 ); posterior lobe elevated high above the head. Hind third of posterior pronotal lobe sloped posteriad, building an obtuse angle with the rest of the pronotum. Hind margin of pronotum weakly bisinuate. Scutellar spine subequal in length to posterior pronotal lobe, vertical (to the plane of meso- and metanotum), slightly curved posteriad. Legs as long or longer than body, hind legs the longest; femora slightly bent ( Figs. 12–13 ). Fore femora ( Fig. 16 ) with a curved subterminal spine. Fore tibia thickened on tip, semicircularly incised, with a terminal comb of setae. Fore and hind wings well developed (all specimens regardless of sex macropterous), somewhat shorter than abdomen, reaching the middle of tergite VI (last abdominal gland opening not visible with wings in repose) ( Figs 17, 20 ). Abdomen thinnest around segment II and broadest at segment V. No abdominal segments fused, segment borders smooth and not elevated. Lateral segment outlines straight or slightly and broadly convex at most. Hind border of segment VII in lateral outline slightly concave ( Figs 18, 21 ). Segments VIII and IX (pygophore) sunken into segment VII, segment VIII indistinct in lateral view ( Fig. 18 ). Ventral pilosity on pygophore long ( Figs 19 , 43 ). Hypandrium broadly elevated and expanded terminally, building short parandria directed dorsoanteriad ( Figs 37–38 , 43 ); posterior margin of hypandrium in lateral view broadly rounded, not angulate. Paramere with an expanded middle part, terminating in a process directed dorsoposteriomediad ( Figs 38 , 43–44 ).

Female. Very similar to male in coloration, vestiture, sculpture and structure. Differences in abdominal structure, with abdomen broadest at segment IV and not V as in male, maximal abdominal width also being slightly higher in female. Abdominal segment borders ( Fig. 20 ) smooth except for slight bulging between segments VI–VII. Outlines of abdominal segments similar to male except segment IV and V convex and segment VI concave (all straight in male). Sternite VII without medial incision, ventral side of the segment being ca. as long as the dorsal one ( Fig. 48 ). Valvula I short, dark brown, valvula II well visible, dark brown to black ( Fig. 22 ). Valvifer II short and broad, brown, but the median margins testaceous as neighbouring parts of tergite IX.

Measurements. Body length JJ 7.80–7.90 mm, ♀ 8.50 mm; head width (= max. body width) JJ 1.34–1.38 mm, ♀ 1.50 mm. Total antenna length JJ 9.06–10.20 mm, ♀ 10.54–10.62 mm (average segment ratios for both sexes together, I to IV: 1.00-1.46-1.72-1.98). Ratio antenna: body 1.16–1.29 in JJ, 1.24 in ♀. labium length JJ 1.75–1.86 mm, ♀ 2.13 mm. Distance between ocelli JJ 0.05–0.06 mm, ♀ 0.06 mm, between ocellus and eye JJ 0.30–0.31 mm, ♀ 0.35 mm, ratio in JJ 5.08–6.10, in ♀ 5.75. Length of collar+middle lobe of pronotum JJ 0.46–0.47 mm, ♀ 0.50 mm; length of posterior pronotal lobe JJ 0.94–1.00 mm, ♀ 1.10 mm, ratio of the two measurements in JJ 2.00–2.17 and in ♀ 2.20. Scutellar spine length JJ 0.96– 1.04 mm, ♀ 1.12 mm; ratio to length of posterior pronotal lobe in JJ 0.96–1.11 and in ♀ 1.02. Measurements of the hind tarsus (segments I / II / III, respectively): JJ 1.17–1.27 / 0.20 / 0.29–0.30 mm, ♀ 1.22 / 0.21 / 0.30 mm, total length of the hind tarsus JJ 1.66–1.77 mm, ♀ 1.73 mm. Maximum width of abdomen JJ 1.13–1.17 mm, ♀♀ 1.37 mm, minimum width JJ 0.52 mm, ♀♀ 0.60 mm, ratio in JJ 2.17–2.25 and in ♀♀ 2.28.

Etymology. The specific epithet is derived from the Latin niger (black) and spina (spine), referring to the coloration of the scutellar spine in this species, which is unique among the known Phaenacantha species ; noun in apposition.

Distribution. Malaysia (Sabah).

Figures

Figs 12–16. Phaenacantha nigrispina sp. nov., holotype. 12 – habitus, dorsal view. 13 – habitus, lateral view. 14 – head and thorax, dorsal view. 15 – head and thorax, lateral view. 16 – right fore femur with the spine. Insert – specimen label.Abbreviations: col = pronotal collar, mp = middle lobe of the pronotum, pp = posterior lobe of the pronotum.

Figs 17–22. Phaenacantha nigrispina sp. nov., holo- and paratype, abdomen with terminalia in situ. 17–19 – holotype male, 20–22 – paratype female. 17, 20 – dorsal view. 18, 21 – lateral view. 19, 22 – caudal view. Abbreviations: ag = dorsoabdominal gland, hyp = hypandrium, pyg = pygophore, t = tergite, val = valvula, vf = valvifer.Abdominal segments are indicated with Roman numbers.

Figs 35–40. Male genitalia of the new Phaenacantha species. 35, 37, 39 – pygophore in left lateral view, with the left paramere detached to make the hypandrium better visible. 36, 38, 40 – pygophore with intact parameres in dorsal view. 35–36 – P. grimmae sp. nov., holotype. 37–38 – P. nigrispina sp. nov., holotype. 39–40 – P. paveli sp. nov., holotype. Abbreviations: hyp = hypandrium, p = paramere, par = parandrium, pyg = pygophore.

Figs 41–46. Male genitalia of the new Phaenacantha species. 41, 43, 45 – pygophore in caudal view, parameres intact. 42, 44, 46 – outer surface of the left paramere. 41–42 – P. grimmae sp. nov.; 43–44 – P. nigrispina sp. nov.; 45–46 – P. paveli sp. nov. Abbreviations: hyp = hypandrium, p = paramere, par = parandrium, pyg = pygophore.

Figs 47–48. Female abdomen tip in new Phaenacantha species, ventrolateral (oblique) view; note the deep broad semicircular median incision of the 7th sternite in 47. 47 – P. grimmae sp. nov. 48 – P. nigrispina sp. nov. Abdominal segments are indicated with Roman numbers.

Figs 1–5. Phaenacantha grimmae sp. nov., paratype. 1 – habitus, dorsal view. 2 – habitus, lateral view. 3 – head and thorax, dorsal view. 4 – head and thorax, lateral view. 5 – right fore femur with the spine. Insert – specimen label. Abbreviations: col = pronotal collar, mp = middle lobe of the pronotum, pp = posterior lobe of the pronotum.

Figs 6–11. Phaenacantha grimmae sp. nov., paratypes, abdomen with terminalia in situ. 6–8 – paratype male, 9–11 – paratype female. 6, 9 – dorsal view. 7, 10 – lateral view. 8, 11 – caudal view. Abdominal segments are indicated with Roman numbers. Insert – labels of the female paratype. Male paratype illustrated is the same as in Figs 1–5.Abbreviations:ag = dorsoabdominal gland, hyp = hypandrium, pyg = pygophore, t = tergite, val = valvula, vf = valvifer.