Vaabonbonphyllium, Cumming & Le Tirant, 2022

Cumming, Royce T. & Le Tirant, Ste ́ phane, 2022, Three new genera and one new species of leaf insect from Melanesia (Phasmatodea, Phylliidae), ZooKeys 1110, pp. 151-200 : 151

Vaabonbonphyllium gen. nov.

Type species.

Phyllium groesseri Zompro, 1998: 159, herein designated.

Taxonomic hierarchy.

Several features link this genus to the Phylliini genera and not the Nanophylliini , such as males with the alae radius split near the wing base (not splitting on the distal half of the wing as in Nanophyllium and Acentetaphyllium gen. nov.), females with tegmina venation similar to Chitoniscus due to the diverging radius and media veins and distinct cubitus anterior and cubitus posterior (cubitus only weakly bifurcate or not bifurcate in Nanophyllium ), and both sexes have a singular posteromedial head tubercle (not bilobed as in Nanophyllium or Acentetaphyllium gen. nov.). Due to these notable morphological features, we place this herein described genus within the tribe Phylliini Brunner von Wattenwyl, 1893.

Discussion.

The selected type species for this new genus is Phyllium groesseri Zompro, 1998 (= Vaabonbonphyllium groesseri (Zompro, 1998), comb. nov.) as this was the first species described from within this new genus and this species is well represented by multiple specimens from the geographically isolated Solomon Islands (Fig. 4 ). Unfortunately, fresh specimens of either species within this genus have not yet been sequenced so hopefully this species can be collected one day and sequenced to add clarity to the higher-level taxonomy.

Autapomorphic features.

Within females, the first radial vein (R1) of the tegmina splits from the radius early on, ca. one third of the way between the wing base and the radius to media crossvein (R-M)/the bend in the radial sector (Fig. 4B ) versus all other phylliids which have the first radius splitting from the radius midway or more than midway from the wing base to the radius to media cross vein (R-M)/the bend in the radial sector or even after this point.

For males, the media (M) vein of the tegmina runs parallel with the radial sector (Rs) several vein widths away and the media posterior (MP) splits on the distal half of the tegmina, bends immediately and runs parallel with the media anterior (MA) to the wing apex (Fig. 3B ) versus in other genera typically the media and radial veins run side by side touching or nearly so, and the posterior branch(es) of the media split on the proximal half or near the middle of the length and run diverging (not parallel) from the media posterior and run to the wing margin, not the apex (Fig. 3A ).

Generic characteristics.

The Vaabonbonphyllium gen. nov. are small to medium, with females ca. 70.0 mm in length (in Vaabonbonphyllium groesseri comb. nov.) and with males from ca. 43.0 mm ( Vaabonbonphyllium groesseri comb. nov.) to ca. 53.0 mm (in Vaabonbonphyllium rafidahae gen. et sp. nov.).

Antennae. Females have antennae with nine segments with segments I, III, and IV notably broader than the other segments and the terminal antennae segment is as long as the preceding three and a half segments (Fig. 10D ). Males have antennae with around 22 segments (in Vaabonbonphyllium groesseri comb. nov. both known male specimens have broken antennae that are missing segments, therefore they only have 19 or 20 segments, but in Vaabonbonphyllium rafidahae gen. et sp. nov. there are 22 segments that are not broken; Fig. 11F ) and most segments covered in setae which are longer than the segment is wide.

Head capsule. Males have well-developed ocelli (Figs 11C , 12G ) and female lack ocelli (Fig. 10C ). Males have compound eyes which are strongly protruding and occupy ca. 2/5 of the head capsule lateral margins (Fig. 11C ) versus females which have compound eyes which are notably smaller, only occupying ca. ¼ of the head capsule lateral margins and which to not strongly protrude from the capsule (Fig. 10C ). In both sexes the head capsules are marked throughout by weak (Fig. 10C ) to distinct granulation (Fig. 12G ) which is relatively evenly spaced. The posteromedial head tubercle is singular and distinctly raised from the head capsule (Figs 11E , 12H ).

Thorax. The thorax is similar in both sexes with the pronotum notably longer than wide (Figs 10C , 11B , 12G ). The mesopleurae are gradually diverging from the anterior to the posterior and are marked with four to six tubercles and some minor granulation throughout (Figs 10C , 11B , 12G ). In both sexes the prescutum is ca. 2X wider on the anterior than long with lateral margins marked by three to five nodes/tubercles, and a prescutum surface which can be relatively smooth or slightly granular. When viewed laterally, both sexes have the prescutum anterior rim marked with a raised sagittal spine (Fig. 12H ).

Legs. Both sexes have interior tibial lobes on the protibiae which do not span the full length of the shaft (only occupying the proximal ½ to 4/5, but not fully reaching), have two lobes on the protibial exterior (one on the distal end which is smaller and one near the middle which is larger; Figs 10F , 11B , 12C ), and the meso-, metatibiae are mostly bare except for the exterior distal ends which can be variable, by either being slightly raised or with small to medium sized lobes present (Fig. 12D , 12E ). In both sexes the profemoral interior lobe is broader than the exterior lobe and marked with three or four broad teeth which can be more sharply pointed (Fig. 11B ) or dulled (Fig. 12C ). Both sexes have the interior mesofemoral lobes slightly broader or about even in width to the exterior lobes, and both lobes can have serration on the distal ½ to 1/3 of the lobe, but the interior lobe serration is more prominent than the exterior lobe. Both sexes have the interior metafemoral lobes several times broader than the exterior lobes and the interior lobes are prominently marked by serration.

Wings. Female tegmina are always long, reaching onto abdominal segments VIII or IX and male tegmina are moderate in length, reaching onto abdominal segment III. Female alae are highly reduced to no more than just a nub and male alae are fully developed in an oval-fan configuration reaching slightly past the apex of the terminal abdominal segment. Female tegmina have a subcostal (Sc) vein which is simple and runs parallel with the wing margin for ca. ⅕ of the wing length before fading; radial vein which diverges steadily away from the media and splits into the first radial vein (R1) which diverges from the radius (R) early on, ca. ⅓ of the way between the wing base and the radius to media crossvein (R-M)/the bend in the radial sector, the primary vein terminates as the radial sector (Rs) on the wing margin just past the middle of the wing length, and as a small radial to medial crossvein (R-M) which does fully connect; the media vein (M) runs side by side the cubitus vein (Cu) and splits into the media anterior (MA) ca. halfway through the wing length and the media posterior (MP) diverges from the cubitus near the distal third of the wing length; the cubitus vein runs along the wing margin until it splits into the cubitus anterior (CuA) and cubitus posterior (CuP) near the distal quarter of the wing; and a first anal vein fuses with the cubitus early on (Fig. 4B ). Male tegmina have a simple subcoastal vein; a radial vein (R) which runs parallel with the media (M) throughout the full length of the wing and branches into the first radial (R1) ca. 2/5 of the way through the wing length and the primary vein terminates as the radial sector (Rs) at the wing apex; the media runs parallel with the radius and splits into the media posterior (MP) near the distal 2/5 of the wing, bends immediately and runs parallel with the media anterior (MA) until reaching the wing margin; the cubitus is unbranched and runs along the wing margin; and there is a first anal which fuses with the cubitus ca. ⅓ of the way through the wing length (Fig. 3B ). Male alae (Fig. 3B ) have a costal vein (C) running along the anterior margin and a subcostal vein (Sc) which runs for nearly the same length parallel with the costal vein; the radial vein (R) is bifurcate when it splits slightly less than 1/3 of the way through the wing length where they gradually diverge, run parallel/subparallel, then converge gradually to the apex where they terminating very near each other but not touching; the media (M) is also bifurcate, splitting about 1/8 of the way through the alae length and these veins run parallel for most of their length until the media posterior (MP) fades near the wing apex and the media anterior (MA) fuses with the radial sector near the wing apex; the cubitus (Cu) is fused with the first anterior anal (1AA) for ca. ¾ of the length until the first anterior anal splits and runs to the wing margin and the cubitus runs singularly to the wing apex; the anal veins are split into two groups, seven anterior anals (1AA-7AA) and five posterior anals (1PA-5PA).

Abdomen. Abdominal shapes are variable within this genus; females are only known for Vaabonbonphyllium groesseri (Zompro, 1998), comb. nov. and have a boxy abdomen (with segments IV through VI parallel sided) and segment VII strongly lobed and tapering strongly to a narrower segment VIII which is weakly lobed (Fig. 10B ). For the males, Vaabonbonphyllium groesseri comb. nov. have segment II converging to the narrowest point of the abdomen, III diverging (giving the abdomen a pinched waist appearance), IV weakly projecting and converging, V diverging, VI strongly diverging and converging giving it a notable lobe, VII appears variable as one male known has this segment converging (Fig. 11A ) and the other male has a notable lobe on this segment as well (Fig. 11D ), the remainder of the segments converge to the apex. In Vaabonbonphyllium rafidahae gen. et sp. nov. the abdominal shape is simple with all segments similar in width and margins all nearly parallel sided giving it a narrow, blade-like appearance (Fig. 12B ).

Female subgenital plate is moderate in length and width, projecting slightly less than halfway under the terminal abdominal segment; gonapophyses VIII are long, broad, and parallel sided for most of their length, with an apex which projects from under the terminal abdominal segment about as much as the cerci do; the cerci are flat and marked sparsely with a granular surface (Fig. 10E ). Males have an approximately equilateral triangular vomer which is singularly pronged, hooking up into the paraproct (Figs 11G , 12A ).

Egg. Egg morphology is not yet known for this rare genus.

Etymology.

Vaabonbonphyllium meaning "leaf that waits for the night to come". This generic epithet is a compound of the Latinized name Phyllium the type genus for the family (from Greek φυλλον, -ου (phyllon, - oy) + -um; Poitout 2007), coupled with the prefix vaabonbon from the Teop (Tiop) language phrase which means "wait for the night to come" ( Mosel 2019). We wished to honor the original inhabitants of this area by using a traditional language from Bougainville Island, the type locality of the genus. The Teop language is little known and considered a threatened language with as few as 6,000 speakers left in the autonomous region of Bougainville Island ( Mosel 2014). We chose this name as these insects are exceptionally camouflaged and nocturnal, holding still during the day, thus hiding from view and only venturing out at night, making them exceptionally rare in collections and little known. This new genus is neuter in gender, following Phyllium .

Distribution.

At present Vaabonbonphyllium gen. nov. is primarily known from the Solomon Islands ( Vaabonbonphyllium groesseri comb. nov.) and a single record from Western Highlands Province, Papua New Guinea ( Vaabonbonphyllium rafidahae gen. et sp. nov.; Fig. 5 ).

Figures

Figure 3. Male tegmina venation for two of the herein described genera A Rakaphyllium schultzei comb. nov. (MNHU) B Vaabonbonphyllium rafidahae (IMQC) (Coll RC 19 - 106). Abbreviations: Sc (subcosta); R (radius); R 1 (radius 1); Rs (radial sector); Rs + MA (fused radial sector and media anterior); M (media); MA (media anterior); MP (media posterior); Cu + 1 AA (fused cubitus and first anterior anal); 1 AA- 7 AA (first through seventh anterior anal); 1 PA- 5 PA (first through fifth posterior anal); 1 A (first anal).

Figure 4. Female tegmina venation for two of the herein described genera A Rakaphyllium schultzei comb. nov. (SDEI) B Vaabonbonphyllium groesseri comb. nov. (SMTD). Abbreviations: Sc (subcosta); R (radius); R 1 (radius 1); Rs (radial sector); R-M (radius to media crossvein); M (media); MA (media anterior); MP (media posterior); Cu (cubitus); CuA (cubitus anterior); CuP (cubitus posterior); 1 A (first anal).

Figure 5. Distribution map noting all presently known records of Vaabonbonphyllium gen. nov. (denoted as star symbols) and Rakaphyllium gen. nov. (denoted as circle symbols) which were located and had data that could accurately be mapped. See Supplementary File 1 for full details for all records presented.

Figure 10. Vaabonbonphyllium groesseri comb. nov. females A data labels associated with the holotype B holotype, habitus, dorsal C details of head through thorax, dorsal D details of antennae, dorsal E details of genitalia, ventral F front legs, head, and thorax, anterodorsal. Scale bar associated with A and B. A and B photographs by Christian Schmidt (SMTD), other images taken by the first author of specimens from the NHMUK.

Figure 11. Vaabonbonphyllium groesseri comb. nov. males A-C, E, F paratype male, (ANIC (CSIRO )), photographs by Bonnie Koopmans (CSIRO) D, G non-type male (NHMUK), photographs by first author A habitus, dorsal (left front leg is physically detached, photoshopped onto the specimen for this figure) B left front leg, dorsal C details of head through thorax, dorsal D habitus, dorsal E details of head through thorax, lateral F associated data labels G genitalia, ventral. Scale bar only associated with A.

Figure 12. Holotype male Vaabonbonphyllium rafidahae gen. et sp. nov., (IMQC) (Coll RC 19 - 106) photographs by the first author A genitalia, ventral B habitus, dorsal C details of the protibial and profemoral lobes D details of the mesotibial and mesofemoral lobes E details of the metatibial and metafemoral lobes F antenna, dorsal G details of the head and thorax, dorsal H head-thorax, lateral. Scale bar only associated with B.