Phyllium zomproi Größer, 2001: 96.

This new subgenus is restricted to Papua New Guinea (two species; Fig. 3A, B, E) and Queensland, Australia (one species; Fig. 3C, D) (Distribution map: Fig. 4).

Figure 3. 

Dorsal view of the known species within the Phyllium (Walaphyllium), scaled to relative size to show the size differences between species A Phyllium zomproi female, Coll SLT B Phyllium zomproi male, Coll RC 17-336 C Phyllium monteithi female dorsal, Coll RC 16-067 D Phyllium monteithi male dorsal, Coll SLT E Phyllium lelantos holotype male, NHMUK. Scale bars: 10 mm.

This new subgenus is easily separated from the other Phyllium subgenera by the following combination of features: [Male] tegmina media vein with an anterior media vein (MA) and two posterior media veins (MP1 and MP2) (Fig. 5B) and a vomer with a single apical hook (Figs 6D, 8D, 14C); [Female] tegmina venation with the posterior cubitus split into an anterior cubitus (CuA), first posterior cubitus (CuP1), and second posterior cubitus (CuP2) (Fig. 5A), fourth antennal segment about as long as the following segment individually (Figs 7C, 10A), not short disk-like, and adult females lacking developed alae; [Egg] capsule lacking pinnae, instead with a brittle sponge-textured surface and the operculum conically raised (Fig. 11).

Figure 4. 

Distribution map for the known species of Phyllium (Walaphyllium) between Papua New Guinea and Australia.

Features which characterize this new subgenus, but do not necessarily differentiate it from others are: in males well-developed ocelli (Figs 7B, 9B, 14A); adult abdomen margins parallel (in males) or subparallel (in females) (Fig. 3); tibiae lacking exterior lobes (and only protibial interior lobe developed; Figs 6A, B, 8A, B, 14B); profemoral interior lobe with four to five small serrate teeth in both males and females (Figs 6A, B, 8A, B, 14B); and mesopleurae with five to seven well developed but not large tubercles which are nearly uniform in size throughout the length of the mesopleurae (Figs 7A, B, 8E, F, 9B, 14A). Comparisons to all the Phyllium subgenera can be found in Table 1 to summarize distinctive features.

Figure 5. 

Phyllium zomproi wing venation, showing the venation present in the Phyllium (Walaphyllium) A female tegmina, Coll RC 18-175 B male tegmina, Coll RC 17-336 C male alae, Coll RC 17-336.

Of these three species in this new subgenus, only P. monteithi has been in the phasmid breeding community to date and therefore this is the only species with the newly hatched nymph coloration known. Please see the below P. monteithi section for a description of the nymph coloration.

Figure 6. 

Phyllium zomproi. A female, profemora and protibia, dorsal, Coll RC 18-277 B male, profemora and protibia, dorsal, Coll RC 17-336 C female, genitalia, ventral, Coll RC 18-277 D male, genitalia, ventral, Coll RC 17-336.

Walaphyllium meaning “Dancing Leaf”. This subgeneric 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 Wala- which is derived from the indigenous Australian terms “walawalay” used in the Dyirbal language to describe the shake-a-leg dance (Dixon 1972) and “walayi-y,” a verb meaning “to pass by” in the Djagubay language (Patz 1991). Overlapping terms from each of these indigenous languages were investigated as they encompass a large part of the distribution of Phyllium monteithi, which is found in the Wet Tropics of far north Queensland, Australia. Phyllium monteithi is the most common and well-known species of this new subgenus, thus providing an opportunity to pay respect to the original peoples of this region who may have first appreciated this mysterious insect. This new subgenus is neuter in gender, following Phyllium.

Figure 7. 

Phyllium zomproi. A female, head through thorax, dorsal, Coll RC 18-277 B male, head through thorax, dorsal, Coll RC 17-336 C female, antennae, dorsal, Coll SLT D female, lateral, head through thorax, Coll RC 18-277 E male, lateral, head through thorax, Coll RC 17-336.

Phyllium (Walaphyllium) zomproi Größer, 2001 (Fig. 3A, B)

Phyllium (Walaphyllium) monteithi Brock & Hasenpusch, 2003 (Fig. 3C, D)

Phyllium (Walaphyllium) lelantos sp. nov. (Fig. 3E)

Papua New Guinea: Morobe Province, Aseki (Winduwe) (NHMUK & Coll RC); Aseki (Wingia) (Holotype: SDEI & Coll RC); Gulf Province (Kaintiba) (Coll RC).

Despite being a rarer species in private and museum collections, this is a widespread species, with records from two Papua New Guinea provinces (Morobe and Gulf, Fig. 4). In the original description by Größer (2001) the female and egg were illustrated as well as a subadult male. Since this original description, the adult male has been identified within the NHMUK and within the authors collections. The previously unknown adult male morphology is here described for the first time to help better understand this rarely encountered species.

Body size; females: 80.0–86.0 mm; males: 79.0 mm.

Male. Coloration. Coloration description based on the limited male specimens from within the authors collections and the NHMUK collection, not on live material. All specimens examined however were with uniform coloration, with little variation between individuals. Overall coloration pale green throughout most of the body. Head through thorax in the preserved specimens is yellow, but this is in all likelihood due to the drying of the specimen and was probably green in life. Compound eyes rusty brown to dark brown color. Antennae pale green or tan, with the terminal segments darker brown. Protibial interior lobe, profemoral interior lobe, and mesofemoral exterior lobe with variable brown patches interrupting the green base color. Tegmina with variable patches of light brown on the green base color, the majority of the tegmina is green. Sclerotized section of the alae can have small patches of brown along the veins, but these are fainter than the brown patches on the tegmina. Abdominal segments V and VI with a small faintly formed clear eyespot of similar width on both the segments. Abdominal segment IX with moderate brown markings on the green, with approximately one third to one half of the segment with brown coloration.

Morphology. Head. Head capsule slightly longer than wide, vertex is lumpy with a smooth texture, not overly granular. Frontal convexity stout with a broad point, apex marked with five to seven thin setae. The posteromedial tubercle is not prominent, only slightly raised from the posterior of the head capsule. Antennae. Antennae consist of 22–23 segments (including the scapus and pedicellus), all segments except the scapus and pedicellus and terminal six are covered in moderately dense tan setae that are as long as the antennae segment is wide. The terminal six segments are covered in tan setae that are about as dense as the setae on the other segments but much shorter (some only slightly raised above the segment surface), and the scapus and pedicellus are without setae. Compound eyes large (taking up about half of the head capsule length) but not notably protruding away from the head (Fig. 7B). Three well-developed ocelli are between the compound eyes and slightly raised above the head capsule (Fig. 7B). Antennal fields slightly wider than the scapus width, not notably large (Fig. 7B). Thorax. Pronotum with an anterior margin that is clearly but not strongly concave; lateral margins that are straight for the anterior two-thirds and then clearly angled toward the posterior margin which is slightly more than half of the width of the anterior margin and slightly convex (Fig. 7B). Anterior and lateral margins of the pronotum with distinct rims, and the posterior margin lacks a well-developed rim. Face of the pronotum has a lumpy texture and is marked by a distinct sagittal furrow and crescent shaped pit in the center (Fig. 7B). Prosternum is moderately granulose with nodes throughout of relatively even size. Mesosternum surface mostly wrinkled, not as much granulation as the prosternum. Prescutum about as wide as long, with lateral margins slightly converging to the posterior. Lateral rims with six to seven tubercles of slightly varying size and uneven spacing, with most tubercles prominent. Prescutum crest along the sagittal plane with four or five small nodes. The surface of the prescutum is mostly wrinkled in texture and not prominently raised along the sagittal plane. Prescutum anterior margin marked with a prominent slightly recurved tubercle rising above the surface of the pronotum (Fig. 7E). Mesopleurae narrow, nearly parallel for most of their length, only starting to more strongly diverge after about two thirds of the way through with the posterior the broadest portion (Fig. 7B). Lateral margin with five major tubercles throughout the length, and generally two or three small minor tubercles interspersed (Fig. 7B). Face of the mesopleurae smooth except for two distinct pits, one on the anterior third and one on the posterior third. Wings. Tegmina moderate in length, extending about one quarter of the way into abdominal segment IV. Tegmina wing venation (Fig. 5B): the subcosta (Sc) is the first vein, running smoothly to the margin and is the first to terminate on the wing margin, about two fifths of the way through the overall tegmina length. The radius (R) spans the entire length of the tegmina with the first radius (R1) branching approximately one third through the length, then a second radius (R2) branches approximately two thirds of the way through the length, and the radial sector (Rs) terminates at the wing apex. The media (M) also spans the entire length of the tegmina (as the media anterior MA, terminating at the wing apex). There are two posterior media veins, the first posterior media (MP1) branches near the middle and meets the cubitus at the wing margin and terminates. The second posterior media (MP2) branches after the first posterior media at about the midline and meets with the cubitus near the wing margin. The cubitus (Cu) runs along most of the tegmina margin and terminates past the midline upon meeting the second media posterior. The first anal (1A) vein terminates upon reaching the cubitus proximal to the midline. Alae well developed in an oval fan configuration, long, almost reaching to the posterior margin of abdominal segment VIII. Alae wing venation (Fig. 5C): the costa (C) is present throughout the entire foremargin giving stability to the wing. The subcosta (Sc) spans approximately three quarters of the wing length running alongside the costa vein the entire length. The radius (R) spans nearly the entire wing length and branches approximately two fifths of the way through into the first radius (R1) and radial sector (Rs). These run gently diverging through about half of their length after which they become parallel and start to bend toward the media vein. Instead of terminating at the wing apex or meeting the media vein, they simply thin out and end individually just shy of the apex. The media (M) branches almost immediately into the media anterior (MA) and the media posterior (MP) which run parallel or subparallel with each other throughout their entire lengths. Neither the media anterior or posterior terminate at the wing apex and like the radial veins the media veins simply thin out and terminate just shy of the apex near where the radial veins terminated. The cubitus (Cu) runs unbranched and terminates at the wing apex bending towards the terminated radial and media veins but not fusing with any. Of the anterior anals, the first anterior anal (1AA) fuses with the cubitus at the wing base and does not diverge from the cubitus until three quarters of the way through the wing length where it diverges away from the curving cubitus until the first anterior anal terminates at the wing margin. The anterior anals two through seven (2AA–7AA) have a common origin and run unbranched in a folding fan pattern of relatively uniform spacing to the wing margin. The posterior anals (1PA–5PA) share a common origin separate from the anterior anals and run unbranched to the wing margin with slightly narrower spacing between them than the anterior anals. Abdomen. Abdominal segments II through III only slightly diverging, IV through VII about half as long as wide and with parallel margins giving the abdomen a long boxy appearance. Segments VIII and IX with smoothly rounded margins converging to segment X which is about half as wide as segment IX and with margins that converge more strongly to the apex. Genitalia. Poculum starting two thirds of the way through abdominal segment VIII, broad with rounded margins, and ending in an apex that slightly passes the anterior margin of segment X and has a distinct cleft in the center (Fig. 6D). Cerci long and slender with at least half of their length protruding from under the terminal abdominal segment, margins slightly cupped, surface covered throughout in thin setae and a granular surface. Vomer not particularly broad, with nearly straight sides evenly converging to the single apical point that hooks upwards into the paraproct (Fig. 6D). Legs. Profemoral exterior lobe smoothly arcing evenly end to end and at its widest is only slightly thinner than the interior lobe. Profemoral exterior lobe margin lacking teeth but does have a slightly granular surface with minimal short setae throughout (Fig. 6B). Profemoral interior lobe rounded without a strong angle and marked with three to four prominent serrate teeth with wide looping gaps between each tooth, the gap in the center is only slightly wider than the gaps on each side (Fig. 6B). Mesofemoral exterior lobe arcs end to end with a distinct bend on the distal third which marks the widest portion of the lobe, no teeth present on the exterior lobe. Mesofemoral interior lobe thinner than the exterior lobe, smoothly arcing from end to end without a distinct bend and with six serrate teeth on the distal half only. Metafemoral exterior lobe without serrate teeth and not broad, straight along the metafemoral shaft. Metafemoral interior lobe wider than the exterior, gently arcing with ten to eleven small serrate teeth throughout the distal three quarters of the length. Protibiae lacking exterior lobe, interior lobe reaching end to end in a rounded scalene triangle, broadest on the distal end (Fig. 6B). Meso- and metatibiae simple, lacking lobes completely.

Australia, Queensland: Mt. Lewis, near Julatten (Holotype: QMBA); Garrandunga, Polly Creek (Coll RC); Windsor Tableland, NE Mt. Carbine (Paratype: QMBA); Mt. Windsor, Tableland (Paratype: UQIC); Kuranda (Paratype: ANIC; Coll JHT); Innisfail (Paratype: QMBA); Atherton, Tableland (Paratype: QDPC); Cairns District (Paratype: UQIC); Gadgarra State Forest, nr Lake Tinaroo (Paratype: QDPC).

Records taken from specimens examined and from Brock and Hasenpusch (2003).

Phyllium monteithi is the most common phylliid species from Australia (the second and only other species being Nanophyllium australianum Cumming, Le Tirant, & Teemsma, 2018 which is exceedingly rare). For the Phyllium (Walaphyllium) new subgenus, this is the most commonly encountered species and has been in the phasmid breeding community for numerous years.

Figure 8. 

Phyllium monteithi. A female, profemora and protibia, dorsal B male, profemora and protibia, dorsal C female, genitalia, ventral D male, genitalia, ventral E female, thorax, dorsal F male, thorax, dorsal. All specimens, Coll SLT.

Female Phyllium monteithi can be differentiated from Phyllium zomproi by several morphological features. One is the number of teeth on the stridulatory file of the third antennal segment with 27 to 29 teeth on P. monteithi (Fig. 10C) and 48 to 50 teeth noted on P. zomproi (Hennemann et al. 2009). There is a notable difference in body size between the two species, with P. monteithi a medium sized species ranging from 75.0–76.0 mm and P. zomproi a large species ranging from 80.0–86.0 mm in length. Additionally, the tubercles on the thorax of P. zomproi are more prominent than those found on P. monteithi and the point of the subgenital plate in P. zomproi is more pronounced than in P. monteithi.

Figure 9. 

Live male Phyllium monteithi, Coll JHT. A full body, dorsal B detail of profemora, head, and thorax, dorsal view C detail of antennae and head, lateral view D genitalia detail, ventral view.

Body size: males: 61.0–64.0 mm, females: 75.0–76.0 mm.

General color throughout the antennae, head, and thorax is dark brown (Fig. 12). The abdomen is of a similar dark brown color but with pale green and brown muddled in. Margins of abdominal segments II through IV with pale mint green margins versus the other segments which have margins which are of a similar muddled brown color like the base color of the segment. Metanotum lateral margins with a distinct pale mint green patch of color. Base coloration of the legs goes from lightest on the anterior pair to darkest on the posterior pair, with the first pair having a burnt orange color, the middle pair a reddish brown color, and the final pair the darkest with a similar dark brown color found on the rest of the body. Meso- and metafemora with a small transverse white band on the proximal end and a broken white transverse line in the middle of the leg segment. Protibiae are the same burnt orange color as the profemora. Meso- and metatibiae are the same color as their adjoining femora, and both have a white patch of color on the proximal portion. Probasitarsi are a golden yellow and the other basitarsi are cream in color.

Figure 10. 

SEM image of female Phyllium monteithi antennae, Coll JHT. A full antenna B details of the stridulatory file of the third antennomere C antennomere III in full. Abbreviations: sf = stridulatory file; sr = stridulatory ridge.

Figure 11. 

Known eggs for the Phyllium (Walaphyllium). A–D P. zomproi, (Coll RC 19-161) A lateral B dorsal C ventral D opercular (anterior) E–H P. monteithi, (Coll RC 17-289) E lateral F dorsal G ventral H opercular (anterior).

Figure 12. 

Phyllium (Walaphyllium) monteithi recently emerged first instar nymph showing the unique coloration which may be present in the other members of this new subgenus. Photographs courtesy of Bruno Kneubühler. A dorsolateral view B dorsal view.

Holotype ♂: Papua New Guinea, Watut, Morobe Province, I.1992. NHMUK 012497024. Deposited in the Natural History Museum, United Kingdom (NHMUK), (Fig. 3E).

The female and eggs are currently unknown; therefore, differentiation is only given for male morphology. This new species is the smallest within the newly erected subgenus, with the holotype only 53.3 mm long, versus males of P. monteithi 61.0–64.0 mm or P. zomproi at 79.0 mm (Figs 3B, 3D, versus 3E). An easy morphological feature to differentiate males of the three species is the radial venation of the tegmina. In P. lelantos sp. nov. the radial vein is split only once into the first radial and the radial sector; P. zomproi has the radial split twice, into the radial sector, the first radial, and the second radial; P. monteithi has the radial split more than the others with at least four prominent radials as well as the radial sector (and occasionally a weak but present fifth radial near the wing apex is also present in some specimens). The profemoral exterior lobe is also notably thinner in P. lelantos sp. nov. only one or one and a half times wider than the profemoral shaft width (Fig. 14B) versus P. monteithi and P. zomproi which can have a profemoral exterior lobe width as many as two or two and a half times wider than the profemoral shaft (Figs 6B, 8B).

Morphologically, P. lelantos sp. nov. appears to be most similar to P. monteithi based on the thorax spination, with the less pronounced mesopleurae tubercles and the anterior prescutum rim with a weakly formed sagittal tubercle (Fig. 14D) versus the prominently raised anterior prescutum rim in P. zomproi (Fig. 7E). Another similarity of P. monteithi and P. lelantos sp. nov. are the terminal abdominal segments with the lateral margins of abdominal segments VIII and IX having straight converging margins, versus P. zomproi which has rounded terminal abdominal segments.

Female and egg. Unknown.

Male. Coloration. Coloration description is based on the single preserved holotype specimen. It is expected that live individuals are likely vibrant green in life. Overall coloration green throughout with yellow to tan discoloration in places due to the drying of the specimen. Compound eyes and the four terminal antennae segments are of a rusty brown color darker than the tan on the head or thorax. The rest of the antennae are of a tan to green color. The protibial interior lobe has brown marking throughout most of the surface, this is the only lobe that has brown colorations, the others are a normal green like the rest of the body. The head through to the thorax are more tan than green in the dried specimen but were likely a darker green in life. There are two faint circular eye spots on the fifth abdominal segment with all others lacking markings.

Figure 13. 

Phyllium lelantos sp. nov. holotype male, NHMUK. A dorsal B ventral. Insert Data labels, “Papua New Guinea, Watut, Morobe Province, I. 1992; NHMUK 012497024”.

Morphology. Head. Head capsule slightly longer than wide, with a vertex marked by sparse, small evenly sized nodes. Frontal convexity stout with sides that converge to the point which is slightly recurved, not straight; the surface is sparsely covered in thin transparent setae (Fig. 14A). Antennae. Antennae consist of 22 segments (including the scapus and pedicellus). The scapus and pedicellus lack setae, the terminal five antennae segments are covered in dense setae that are short, and the remaining antennae segments are covered in long, thin setae which are longer than each segment is wide. Compound eyes are large, notably protruding away from the head capsule and taking up about half of the length of the capsule lateral margins (Fig. 14A). Ocelli are present and well-developed (Fig. 14A). Thorax. Pronotum with anterior margin that is slightly concave and lateral margins that are straight and uniformly converging to a straight posterior margin that is about half the width of the anterior rim. Anterior and lateral margins of the pronotum have distinct rims, and the posterior margin lacks a rim (Fig. 14A). Face of the pronotum is marked by a distinct sagittal and transverse furrow meeting at a central pit with the remainder of the surface slightly lumpy in texture. Prosternum is moderately granulose throughout with nodes of even size and slightly uneven spacing as well as a slightly more prominent central node which is more prominent than the others (Fig. 14D). Mesosternum surface wrinkled and marked with nodes throughout. Prescutum anterior margin is wider than the prescutum is long, with lateral margins that converge to the posterior margin that is approximately three-quarters as wide as the anterior rim. Lateral rims with five nodes of slightly varying size but nearly even spacing. Prescutum crest along the sagittal plane nearly bare, with only a single small node present near the anterior rim and one more small one near the posterior, the rest of the sagittal crest lacks features and is just smooth (Fig. 14D). Prescutum anterior margin not particularly prominent, only marked with a single small tubercle (Fig. 14D). Mesopleurae narrow, with margins which are straight, only slightly diverging along their length. Lateral margin marked with six tubercles spread throughout the length almost evenly, with the smallest near the anterior rim and the rest slightly increasing in size as they span towards the posterior (Fig. 14A). Face of the mesopleurae smooth except for two faint divots, one on the anterior third and one on the posterior third. Wings. Tegmina short, only extending half way through abdominal segment III. Tegmina venation can only be noted to the best of our ability from the folded wings of the holotype specimen. For the tegmina, the subcosta (Sc) is the first vein and rather long, running smoothly along the wing and terminates just past the midline of the wing length. The radius (R) spans the entire length of the tegmina with the radial sector (Rs) terminating at the wing apex and a single first radius (R1) branching just before the midline and terminating at the margin three quarters of the way through the tegmina length. The media (M) also spans the entire length of the tegmina (as the media anterior MA, which terminates at the wing apex). There are two posterior media veins, the first posterior media (MP1) branches before the midline and meets the cubitus at the wing margin where the first posterior media terminates. The second posterior media (MP2) branches after the first posterior media near the midline and meets with the cubitus near the wing margin. The cubitus (Cu) vein runs along most of the tegmina margin and terminates about three quarters of the way through the tegmina length upon meeting the second media posterior. The first anal (1A) vein terminates upon reaching the cubitus about one-third of the way along the tegmina length. Alae long and well developed in an oval fan configuration, extending to the posterior margin of abdominal segment IX. Alae wing venation cannot be seen fully due to the folded wings, but what can be seen is that there is a fully developed costa (C), subcosta (Sc), and first radius (R1) present along the length of the alae running parallel with each other to the apex of the wing. Abdomen. Abdominal segments II through the anterior half of IV gradually and uniformly diverging, posterior half of IV through VII parallel, with each segment only about one and a half times wider than long giving the abdomen a thin boxy appearance. Segments VIII through X converging to the apex but with slightly rounded margins, not perfectly straight. Abdominal segment X has margins which are lined with stout setae, very similar to those which line the cerci margins. Genitalia. Poculum starting at the anterior margin of abdominal segment VIII, uniformly broad throughout its length, and ends in a broad slightly rounded apex that slightly passes the anterior margin of segment X (Fig. 14C). Cerci about as long as the vomer, with about half of the length extending from under abdominal segment X. Cerci are slightly cupped and have a surface which is weakly granular. Cerci margins are lined with stout tan setae with those on the exterior margins more prominent than those on the interior margins. Vomer moderately long, extending about three-quarters of the way under segment X with sides that are evenly converging, the single apical point is broad and hooks upwards into the paraproct (Fig. 14C). Legs. Profemora exterior lobe slightly wider than half the width of the interior lobe, no small teeth are present but the entire length has short tan setae relatively evenly spaced, and the lobe arcs smoothly along the profemoral shaft without a distinct bend. Profemoral interior lobe roundly triangular without a strong angle and marked with five teeth. The proximal most tooth is smaller than the rest but clearly present, the remaining four teeth are of a similar size and with wide looping spacing except between the distal two which have slightly wider spacing than the others. Exterior mesofemoral lobe arcs end to end with a slight rounded angle in the center, and only on the distal half of that gentle bend are three to five small serrate teeth. The exterior mesofemoral lobe ends in a prominent spur near the mesotibial joint, this spur is larger than any of the preceding small serrate teeth. Interior mesofemoral lobe is slightly narrower than the exterior lobe and lacks a distinct bend, instead hugging the mesotibial shaft. On the distal half only of the interior mesofemoral lobe there are five to six serrate teeth which are larger than the exterior lobes teeth. Metafemoral exterior lobe lacks teeth, is nearly straight, and runs uniformly along the metafemoral shaft. Metafemoral interior lobe slightly wider than the exterior lobe and with nine to ten small serrate teeth throughout slightly more than half of the length. Protibiae lacking an exterior lobe, interior lobe reaching end to end in a smooth scalene triangle, with the broadest portion on the distal end (Fig. 14B). Uniformly throughout the protibial lobe margins are similar stout setae as those found on the profemoral lobes margins. Meso- and metatibiae simple, lacking lobes completely.

Figure 14. 

Phyllium lelantos sp. nov. holotype male. A head and thorax, dorsal B front leg, protibiae and profemora, dorsal C genitalia, ventral D thorax, lateral view.

Noun. Because leaf insects are such cryptic insects so rarely observed, or in this case only known from a single specimen, we felt that the homage of Lelantos the Greek minor Titan of “moving unseen” was fitting. Lelantos’ name is derived from the Greek Ληλαντος (lêthô, lanthanô, and lelathon), meaning “to escape notice”, “move unseen”, or “go unobserved” (Rouse 1942).

Only known from the holotype specimen from Papua New Guinea, Morobe Province, Watut (Fig. 4).

Length of body (including cerci and head, excluding antennae) 53.3, length/width of head 3.8/2.8, antennae (but slightly bent so measurement is slightly off) 12.0, pronotum 2.5, mesonotum 1.5, length of tegmina 15.1 (left) and 11.8 (right, which appears to be slightly aberrant and dwarfed), length of alae 38.5, greatest width of abdomen 10.5, profemora 7.4, mesofemora 8.8, metafemora 11.0, protibiae 5.8, mesotibiae 5.7, metatibiae 7.5.