Rakaphyllium, Cumming & Le Tirant, 2022
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publication ID |
https://dx.doi.org/10.3897/zookeys.1110.80808 |
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publication LSID |
lsid:zoobank.org:pub:7311F29E-9878-40FE-935B-6B1E061262B2 |
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persistent identifier |
https://treatment.plazi.org/id/2C2C6B6B-83F4-4341-954C-351E92119BEA |
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taxon LSID |
lsid:zoobank.org:act:2C2C6B6B-83F4-4341-954C-351E92119BEA |
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treatment provided by |
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scientific name |
Rakaphyllium |
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gen. nov. |
Rakaphyllium gen. nov.
Type species.
Pulchriphyllium schultzei Giglio-Tos, 1912: 56, herein designated.
Taxonomic hierarchy.
This genus has a combination of features which link it to several genera, thus making a higher-level taxonomic placement difficult and requiring molecular confirmation in the future. The thorax and tegmina venation in the females are reminiscent of some Pulchriphyllium sensu stricto species and the profemoral and protibial lobes are reminiscent of some Phyllium Illiger, 1798 and Comptaphyllium Cumming et al., 2019 species, whereas the male thorax is similar to Trolicaphyllium Cumming et al., 2021. At present within Phylliidae there are two recognized tribes, the Nanophylliini Zompro and Größer 2003 (which contains only the Nanophyllium Redtenbacher, 1906) and the Phylliini Brunner von Wattenwyl, 1893 (which contains all other genera). Therefore, at this time this genus is placed within the tribe Phylliini as notable features such as a two lobed posteromedial tubercle and a prescutum which is wider than long (features which help to define the Nanophyllium ) are absent, suggesting a closer relationship to other genera instead.
Discussion.
The selected type species for this new genus is Pulchriphyllium schultzei Giglio-Tos, 1912 (= Rakaphyllium schultzei (Giglio-Tos, 1912), comb. nov.) as this was the first species described within this new genus, the holotype is from an exact collection locality, and this species appears to be the more commonly encountered of the two species within this new genus.
This new genus has been recognized as unique in the past, as this clade was designated as the Rakaphyllium schultzei species group within Hennemann et al. (2009) based upon the shorter tegmina and the two lobes on the exterior protibiae. While these features are helpful to differentiate this genus from others, the below noted autapomorphic features allow differentiation from all phylliid genera.
Autapomorphic features.
Within each sex there is an easily observed morphological feature which supports their monophyly and readily separates them from other phylliid genera. For females, the gonapophyses VIII are exceptionally long, with approximately half of their length projecting from under the terminal abdominal segment (Figs 7G View Figure 7 , 9D View Figure 9 ), a feature not seen in any other phylliid as typically gonapophyses VIII only reach to the apex of the terminal abdominal segment or at most only exceed the tip slightly (Fig. 10E View Figure 10 ). For males the alae venation is unique as the radius vein is simple (Fig. 3A View Figure 3 ), not bifurcate as is seen in all other phylliid genera (Fig. 3B View Figure 3 ). These autapomorphic features help to define the new genus Rakaphyllium gen. nov. within the phylliids as well as differentiate them from the Pulchriphyllium sensu stricto.
Generic characteristics.
The Rakaphyllium gen. nov. are average sized phylliids, with females ranging from ca. 80 mm to 90 mm long and males ca. 60 mm long. Typical coloration appears to be green, but with so few specimens known and color variation a common occurrence in phylliids it is possible that this genus may also exhibit color forms (such as possibly Rakaphyllium exsectum comb. nov. but this brown coloration may simply be due to the age and preservation technique (Fig. 9 View Figure 9 )).
Antennae. Females have antennae with nine segments with the terminal antennomere not notably long (only as long as the previous one to two segments combined) and segments IV through VIII all of a similar length (Figs 6D View Figure 6 , 7F View Figure 7 , 9E View Figure 9 ). Males have antennae which range from 20 to 23 segments with most segments covered densely in setae, and overall antennomere shape somewhat flattened.
Head capsule. Males have well-developed ocelli (Fig. 8B View Figure 8 ), females do not have ocelli (Figs 6D View Figure 6 , 7H View Figure 7 ). Males have compound eyes which are strongly protruding and occupy ca. 2/5 of the head capsule lateral margins (Fig. 8B View Figure 8 ) versus females which have compound eyes which are notably smaller, only occupying less than 1/3 of the head capsule lateral margins and which do not strongly protrude from the capsule (Fig. 7H View Figure 7 ). Both sexes have head capsules which are marked by irregularly sized and space granulation.
Thorax. The thorax is similar in both sexes with mesopleurae that are narrowly diverging from the anterior to the posterior (evenly so in females, almost parallel in males for the anterior half and then more prominently on the posterior half) are marked on the anterior half with three to four small tubercles with granulation interspersed with the posterior half relatively smooth or with only minimal granulation (Figs 6D View Figure 6 , 7H View Figure 7 ). In both sexes the prescutum is about the same length as the width of the anterior margin, with a posterior margin that is slightly narrower giving the prescutum a slight isosceles trapezoid appearance. The margins of the prescutum are marked with granulation and the prescutum surface is covered with granulation with those along the sagittal plane slightly larger and in males a weak sagittal crest is present (Figs 6D View Figure 6 , 8B View Figure 8 , 9C View Figure 9 ). When viewed laterally, both sexes have a weakly formed prescutum anterior rim with a granular surface (Figs 7B View Figure 7 , 8B View Figure 8 ).
Legs. Both sexes have interior protibial lobes which do not span the full length of the shaft, instead they are only situated on the proximal half (Figs 6B View Figure 6 , 7C View Figure 7 ) and exterior protibiae which are marked by two lobes, one on the proximal and one on the distal end (Figs 6B View Figure 6 , 7C View Figure 7 ). The exterior meso- and metatibiae are notably reduced, but if lobes are present its just as small spurs (sometimes just a distal spur or sometimes one on each end of the shaft) never as prominent lobes. Profemoral exterior lobes are rather variable as within Rakaphyllium schultzei comb. nov. females they are simply arcing smoothly from end to end without a strong angle (Fig. 6B View Figure 6 ), but in Rakaphyllium exsectum comb. nov. females the exterior lobe is distinctly boxy with a right angle (Fig. 9B View Figure 9 ). Males are only known for Rakaphyllium schultzei comb. nov. in which the femoral morphology is similar to the female, simply arcing tightly along the profemoral shaft (Fig. 8B View Figure 8 ).
Wings. Female tegmina are average in length, only reaching onto abdominal segments V or VI and male tegmina are moderate in length, only reaching onto abdominal segment II or III. Females have rudimentary alae. Male alae are fully developed in an oval-fan configuration and reach onto abdominal segments VIII to X. Female tegmina have a subcoastal vein; radial vein which runs parallel with the media and splits into the first radial about halfway through its length and terminates in a radial sector which bends distinctly away from the media and arcs to the wing margin; a bifurcate medial vein; a bifurcate cubitus vein; and a first anal vein which fuses with the cubitus early on (Fig. 4A View Figure 4 ). Male tegmina (Fig. 3A View Figure 3 ) have a simple subcoastal vein; radial vein which runs parallel/subparallel with the media almost throughout the full length of the wing and branches into the first radial about one third of the way through the wing length and terminates as the radial sector; the media runs parallel/subparallel with the radius and has the media posterior split near the middle of the wing and terminates as the media anterior; the cubitus is unbranched; and there is a first anal which fuses with the cubitus early on. Male alae (Fig. 3A View Figure 3 ) have a costal vein running along the anterior margin; a subcostal vein which runs parallel with the costal vein for the full length; the radial vein is the most unique feature of the alae as it is simple, running parallel to the subcostal vein; the media splits early into the media anterior and posterior which run parallel until the media posterior fuses with the media anterior near the wing margin and they run fused to the apex of the wing; the cubitus is fused with the first anterior anal for ca. half of the length until the first anterior anal splits and runs to the wing margin; the anal veins are split into two groups, the anterior anals and the posterior anals (with seven anterior anals and four or five posterior anals).
Abdomen. Both sexes have variable abdominal shapes, but all forms are broad in the middle with the widest segments V or VI; in both sexes the anterior halves are uniformly broadening to the middle segments, and then the posterior half of the abdomen is variable either with smooth margins giving the abdomen an ovoid appearance, or with the posterior segments gently or strongly undulating giving the abdomen a lobed appearance. Female subgenital plate is short and relatively narrow with the apex slightly reaching onto the anterior margin of the terminal abdominal segment and ending in a fine point; gonapophyses VIII are exceptionally long (with ca. half of their length projecting out from underneath the abdomen) with a uniform width through most of their length; the cerci are relatively flat, marked sparsely with a granular surface, and end in blunt points (Figs 7G View Figure 7 , 9D View Figure 9 ). Males have a long, relatively narrow, triangular vomer which is singularly pronged, hooking up into the paraproct (Fig. 8C View Figure 8 ).
Egg. Egg morphology is not yet known for this rare genus, but with such unusually long gonapophyses to hold the eggs before they are flung away, the eggs must have a unique shape to require such ungainly gonapophyses.
Etymology.
Rakaphyllium meaning "walking leaf". 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 raka from the Hiri Motu language of New Guinea which means "to walk" ( Chatterton 1975; Dutton and Voorhoeve 1975). We wish to honor the original inhabitants of this area by using the traditional language of Hiri Motu which is one of the official languages of Papua New Guinea and as Papua New Guinea pushed towards sovereignty in 1975, Hiri Motu was seen as a unifying force which was instrumental in the awakening of national pride ( Dutton and Voorhoeve 1975). We chose this name because of the amazing camouflage these insects possess, allowing them to appear miraculously as a leaf that simply stands up and walks away when disturbed. This new genus is neuter in gender, following Phyllium .
Distribution.
At present our knowledge of the Rakaphyllium gen. nov. is rather limited due to its rarity, however, interestingly despite it being rarely collected, this genus appears to be somewhat widespread, with records from throughout New Guinea, and even a record from the Aru Islands (Fig. 1A View Figure 1 ) off the western coast of Papua Province, Indonesia (Fig. 5 View Figure 5 ).
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