Phyllium crapulatum Cumming, Foley, Hennemann, Le Tirant & Büscher, 2025

Cumming, Royce T., Foley, Evelyn Marie, Hennemann, Frank H., Le Tirant, Stephane, Daawia,, Warikar, Evie Lilly, Yando, Heron, Suhartawan, Bambang, Henze, Katharina, Büscher, Thies H. & Bank, Sarah, 2025, A deeper look into the diversity of Phyllium leaf insects from Indonesia: seven new species and two unique egg morphologies (Phasmatodea, Phylliidae), ZooKeys 1256, pp. 317-370 : 317-370

Phyllium crapulatum Cumming, Foley, Hennemann, Le Tirant & Büscher sp. nov.

Fig. 11

Type material.

Holotype ( ♂): Indonesia • West Kalimantan, Mount Bawang , 00 53.5'N, 109 22.2'E, Elv. 245 Meters, May, 2023. Tissue sample: SLT 069 [ IMQC].

Differentiation.

Female, egg, and freshly hatched nymph unknown. Male Phyllium crapulatum sp. nov. are most similar to Phyllium rubrum and Phyllium bradleri due to their similar sizes, abdominal shapes, tegmina lengths, and thorax shape and spination. Phyllium crapulatum sp. nov. appears most similar to Phyllium rubrum due to the same length tegmina, similar profemoral exterior lobe width, and similar thorax shape and spination. These species were recovered as closely related in our genetic phylogeny (Fig. 1 ) so their morphological similarity is not surprising. Only subtle morphological differences could be found between these species. In Phyllium rubrum , the males have prominently colored ventral surfaces of their coxae (red; a unique occurrence as typically bright coxae colors are only found in females), vs Phyllium crapulatum sp. nov. which does not appear to have colored coxae. Hopefully, once females and eggs can be observed of this species, more morphological differences can be illustrated. Phyllium crapulatum sp. nov. can be differentiated from Phyllium bradleri by the protibial interior lobe shape, as Phyllium bradleri has the distal end of the rounded triangle lobe notably thinner than the proximal end of the lobe, vs Phyllium crapulatum sp. nov. which has a interior lobe that is more evenly distributed across the length, with a distal end similar in width to the proximal end width (Fig. 11 D ).

Description.

Male. Coloration. Coloration based upon the dead, dried holotype (Fig. 11 ). Overall coloration pale green and yellow throughout with highlights of tan / orange. The antennae and compound eyes are the darkest areas on the specimen with burnt orange color. Abdominal segment V has a pair of slightly lighter eye spots that are not prominent. Ventral coxae coloration matches the surrounding tissue.

Morphology. Head capsule slightly longer than wide, with a vertex that is rather smooth. The posteromedial tubercle is singularly pointed and distinctly raised above the head capsule (Fig. 11 E ). Frontal convexities stout and bluntly pointed with sparse setae. Compound eyes large and bulbous, occupying ~ 2 / 5 of the head capsule lateral margins (Fig. 11 D ). There are three well-developed ocelli distinctly raised above the capsule and located between the compound eyes.

Antennae (including the scapus and pedicellus) consist of 25 segments, all segments except the scapus and pedicellus and terminal five segments are covered in dense setae where most are as long as the antenna segment is wide (Fig. 11 D ). The terminal five segments are covered in dense short setae and the scapus and pedicellus are nearly completely bare with only a few sparse setae.

Thorax. Pronotum with slightly concave anterior margin and straight lateral margins that converge to a slightly convex posterior margin that is ~ ½ the width of the anterior margin (Fig. 11 A ). Anterior and lateral margins of the pronotum have distinct rims and the posterior margin has a weakly formed rim (Fig. 11 A ). Face of the pronotum is marked by a distinct pit in the center, a sagittal furrow on the anterior ½, and slight perpendicular furrows originating from the central pit. The pronotum surface is slightly lumpy and lacking distinct granulation (Fig. 11 A ). Prosternum surface is slightly granular. Mesosternum surface anterior 1 / 3 slightly granular, the remainder of the mesosternum surface is relatively smooth (Fig. 11 B ). Metasternum surface finely wrinkled throughout. Mesoprescutum longer than wide, with lateral margins that slightly converge to the posterior margin which is ~ ¾ as wide as the anterior margin (Fig. 11 A ). Lateral margins of the mesoprescutum with six or seven stout tubercles with the anterior three the most prominent (Fig. 11 A ). Mesoprescutum surface slightly raised along the sagittal plane and is marked with three or four distinct but small spines and the remainder of the surface is relatively smooth (Fig. 11 A ). Mesoprescutum anterior rim moderately formed with a distinct sagittal spine, and the remainder of the rim surface is relatively smooth (Fig. 11 E ). Mesopleurae begin on the anterior mesoprescutum margin and diverge at a gradually increasing angle from the anterior to the posterior but are relatively narrow throughout their length (Fig. 11 A ). Mesopleuron lateral margin with seven or eight moderately formed tubercles and a few small nodes interspersed throughout the length (Fig. 11 A ). Mesopleuron face moderately wrinkled and marked by a distinct pit on the anterior 1 / 3 and a smaller pit on the posterior 1 / 3.

Wings. Tegmina moderate length, extending ¼ of the way onto abdominal segment IV. Tegmina wing venation: the subcosta ( Sc) is the first vein, is simple, and terminates ~ 1 / 3 of the way through the overall wing length. The radius (R) spans the entire length of the tegmina with the first radius ( R 1) branching ~ 1 / 3 of the way through the wing length and terminating at the wing margin ~ ½ of the way through the wing length. There is an additional radius ( R 2) branching near the midlength of the tegmina and the radial sector runs straight to the wing apex. The media (M) also spans the entire length of the tegmina and runs side by side along the radius / radial sector with the first media posterior ( MP 1) branching off near the tegmina midlength, followed by a second media posterior ( MP 2) near the distal 2 / 5, and the media anterior ( MA) runs straight to the tegmina apex. The cubitus ( Cu) cuts across the tegmina to the margin ~ 1 / 3 of the way through the length and runs along the edge of the wing where the first and second media posterior veins fuse with it and as the cubitus reaches the apex it fades. The first anal ( 1 A) vein terminates upon reaching the cubitus 1 / 3 of the way through the tegmina length. Alae well-developed in an oval fan configuration, long, reaching to the posterior of abdominal segments IX. Ala wing venation not visible in the holotype specimen.

Abdomen. Lateral margins of abdominal segment II slightly converging, III diverging slightly, IV diverging to the widest point 2 / 3 of the way through the segment length and the remaining 1 / 3 of the segment is parallel, V parallel sided or slightly subparallel (converging slightly), VI through X converging gradually with smooth margins, giving the abdomen a spade-shaped appearance.

Genitalia. Poculum broad and ends in an apex that slightly passes the anterior margin of the abdominal segment X with a margin that is broad and straight (Fig. 11 F ). Cerci long and slender, with slightly> ½ of their length extending from under abdominal segment X, nearly flat, covered in a granulose surface and several short setae with those along the margins slightly longer (Fig. 11 F ). Vomer broad and stout with straight sides evenly converging until near the apex where the margins converge more sharply to the apical hook which is thick and has a singular point (Fig. 11 F ).

Legs. The profemoral exterior lobe is narrow, approx. the same width as the profemoral shaft at its widest. The profemoral exterior lobe margin is relatively smooth (Fig. 11 D ). The profemoral interior lobe is obtusely triangular and at its greatest width it is ~ 2 × the greatest width of the profemoral shaft. The profemoral interior lobe is ornamented with four serrate teeth arranged in a three-one pattern with looping gaps between them, where the third and fourth tooth has a notable wider gap between them (Fig. 11 D ). The central two teeth are notably larger than the first and fourth teeth (Fig. 11 D ). Mesofemoral exterior lobe arcs end to end but is slightly wider on the distal 1 / 3 which is marked with two teeth, while the proximal 2 / 3 of the lobe is thinner and lacks teeth. Mesofemoral interior lobe and mesofemoral shaft are approximately the same width, and the exterior lobe is slightly thicker. The mesofemoral interior lobe is slightly broader on the distal end and the distal ½ is ornamented with six small serrate teeth while the proximal portion of the lobe is thin and lacks teeth. Metafemoral exterior lobe has a straight margin along the metafemoral shaft and is mostly unornamented but does have two small teeth on the distal 1 / 3. Metafemoral interior lobe arcs end to end with nine or ten sharply serrate teeth on the distal ½, which is slightly wider than the smooth proximal portion of the lobe. Protibia lacking exterior lobe; interior lobe reaching end to end as a rounded triangle with the widest portion slightly distal to the midlength with a maximum width of ~ 1.5 × as wide as the protibial shaft width (Fig. 11 D ). Meso- and metatibiae simple, lacking lobes completely.

Measurements of holotype male [mm]. Length of body (including cerci and head, excluding antennae) 63.8, length / width of head 4.4 / 3.8, antennae 28.4, pronotum 3.4, mesonotum 4.9, length of tegmina 25.0, greatest width of abdomen 16.3, profemora 10.9, mesofemora 10.3, metafemora 12.8, protibiae 6.5, mesotibiae 6.6, metatibiae 9.8.

Etymology.

Latin in origin, adjective. Meaning drunk or intoxicated. For anyone who has seen living phylliids, when in the wild on a bush or in a tree, they blend completely with the leaves swaying in the breeze. However, most people rarely see them in the wild, more often they are seen handled as pets indoors or in terrariums which lack a gusty breeze. This results in the leaf insect swaying wildly, as is their natural predisposition ( Leigh 1912; Steiniger 1933), but looking very much like a drunken leaf stumbling home after a wild evening of too much merriment. Hence, the binomial meaning “ drunken leaf ”.

Distribution.

At present known from the type locality; Mount Bawang in West Kalimantan, Indonesia (Fig. 2 ).

Remarks.

This species is part of a small clade comprised of Phyllium rubrum (which is found on Peninsular Malaysia; Fig. 1 ) and an unidentified nymph sample ( Phyllium sp. 5 “ Mt. Bawang ”) which was included within Bank et al. (2021 b) from the same locality as Phyllium crapulatum sp. nov., Mount Bawang, West Kalimantan. Phylogenetically, this unidentified nymph “ Phyllium sp. 5 ” was recovered as more closely related to Phyllium rubrum vs Phyllium crapulatum sp. nov., suggesting that there are likely two different Phyllium species found on Mount Bawang. Unfortunately, as the specimen from Bank et al. (2021 b) is a small nymph, a morphological comparison between Phyllium crapulatum sp. nov. and this nymph cannot be made, and the nymph must remain unidentified.

Figures

Figure 1. Maximum Likelihood tree with focus on the phylogenetic relationships of 54 Phyllium specimens. Tree is rooted with Cryptophyllium as the outgroup. Support values are shown at each node (SH-aLRT / UFBoot). The asterisk (*) indicates maximum support (100). Newly added specimens are shown in green text and new species are highlighted in green. The blue stripes on internal branches mark dispersal to Indonesia, with blue boxes specifying the exact island or region. Abbreviations: HT, holotype; PT, paratype.

Figure 2. Distribution map for all Phyllium species used in the molecular analysis as well as the newly described species from Obi Island not represented in the phylogenetic tree. Species names of Phyllium from Malaysia, the Philippine Islands, and New Britain (Papua New Guinea) are shown in gray. The Indonesian archipelagic state is highlighted in blue and symbols of sampling sites of Indonesian Phyllium species are in dark blue. White symbols show the location of the remaining Phyllium from Malaysia, the Philippine Islands and New Britain (Papua New Guinea). The inset presents an enlarged section of Sabah (Malaysia: Borneo) and the six species found there. Abbreviations: Hal, Halmahera; Jav, Java; Kal, Kalimantan; NG, New Guinea (Papua); Ser, Seram; Sul, Sulawesi; Sum, Sumatra.

Figure 11. Phyllium crapulatum sp. nov. holotype (IMQC). A. Details of thorax, dorsal; B. Habitus, ventral; C. Habitus, dorsal; D. Details of antenna and front leg, dorsal; E. Posterior of head through thorax, lateral (head to the right); F. Terminalia ventral; G. Terminalia dorsal. Scale bar: 20.0 mm (B, C).