Phyllium hennemanni Cumming, Foley, 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 hennemanni Cumming, Foley, Le Tirant & Büscher sp. nov.

Figs 12 , 13 , 14

Type material.

Holotype ( ♀): South Sulawesi, Sulawesi Selatan, Bungadidi, II. 2011, local collector, ex coll. Sigetake Suzuki; tissue sample SB 0642; [ ZSM] . Paratypes: (2 ♀♀, 18 eggs): ( 1 ♀) South-East Sulawesi, Sulawesi Tenggara, Tiulapolu (Tipulu), III. 2008, local collector coll. Sigetake Suzuki . ( 1 ♀) South-East Sulawesi, Sulawesi Tenggara, Tiulapolu (Tipulu), III. 2008, local collector ex coll. Sigetake Suzuki [coll. FH, No. 1091-1] . ( 5 eggs) South-East Sulawesi, Sulawesi Tenggara, Tiulapolu (Tipulu), III. 2008, local collector ex coll. Sigetake Suzuki [coll. FH, No. 1091 - E 1] . ( 1 egg) [ ex ovipositor HT]: South Sulawesi, Sulawesi Selatan, Bungadidi , II. 2011, local collector, ex coll. Sigetake Suzuki [ ZSM] . ( 9 eggs): South Sulawesi, Sulawesi Selatan, Bungadidi , II. 2011, local collector, ex coll. Sigetake Suzuki [coll. FH, No. 1091 - E 2] . ( 3 eggs): South Sulawesi, Sulawesi Selatan, Bungadidi , II. 2011, local collector, ex coll. Sigetake Suzuki [ Coll RC, 20-086, 20-087, and 20-088] .

Differentiation.

Male unknown. Female Phyllium hennemanni sp. nov. (Fig. 13 ) are most similar to Phyllium mamasaense and Phyllium letiranti due to similar femoral lobe shapes / serration and genitalia. Phyllium hennemanni sp. nov. can be differentiated from Phyllium letiranti by the ventral coxae coloration, as Phyllium letiranti has orange ventral coxae coloration while Phyllium hennemanni sp. nov. has a distinct black spot on both the meta- and mesocoxae. Additionally, these species can be differentiated by the mesopleurae of the thorax as Phyllium hennemanni sp. nov. has small nodes throughout the length (giving them a rough marginal texture; Fig. 13 F ) and the mesopleurae angle towards the anterior at a stronger angle, terminating before reaching the anterior end of the mesoprescutum (vs Phyllium letiranti which has distinct spiniform tubercles and the mesopleurae reaching to the anterior margin of the mesoprescutum). Phyllium hennemanni sp. nov. females are most morphologically similar to Phyllium mamasaense and even have the same ventral coxae coloration (black spots on both the meta- and mesocoxae), but these species can be differentiated by their thorax and antennae morphology. In Phyllium hennemanni sp. nov. the mesopleurae margins have small nodes (Fig. 13 F ) vs Phyllium mamasaense which has distinct spiniform tubercles. The number of antennomeres allow differentiation as Phyllium mamasaense has nine segments while Phyllium hennemanni sp. nov. has ten segments (due to the segment prior to the apical segment being split by a prominent suture and these two portions having different textures). The apical antennomere of Phyllium mamasaense is also stouter than the longer and thinner apical antennomere of Phyllium hennemanni sp. nov. (Fig. 13 B ).

Eggs of Phyllium hennemanni sp. nov. (Figs 12 , 14 ) are distinct from all known phylliid species eggs due to the autapomorphic trait of a pair of posteriorly attached, lateral flaps which create a hollow cavity between the flap and the actual egg capsule (Fig. 12 ). The main feature of Phyllium hennemanni sp. nov. eggs which is similar to other known phylliid species is the raised, fused frill running around the margin of the operculum (Fig. 12 A ). The only other species with such a distinct fused capitular frill are Phyllium mamasaense , Phyllium ericoriai , and Phyllium bonifacioi . While the opercular coverage of Phyllium ericoriai and Phyllium bonifacioi is formed by a frill of upright standing pinnae, the structure in Phyllium mamasaense and Phyllium hennemanni sp. nov., are more similar as these opercular pinnae are fused on their entire length (Fig. 14 C ). All three of these species besides Phyllium hennemanni sp. nov. lack lateral flaps on the egg capsule and instead have reinforced ribs (pinnae “ type 4 ” as designated in Büscher et al. 2023). These three species can be differentiated from Phyllium hennemanni sp. nov. by these lateral reinforced ribs (and these reinforced ribs allow differentiation from all other phylliids as well).

Description.

Female. Coloration. Coloration description is based upon the type material, which is dead and dried reasonably well (not too many dark rotten areas; Fig. 13 ). The general coloration is pale green throughout (although some areas have faded to yellow, likely due to the drying process). There are several areas, commonly occurring on other Phyllium species, which appear to be more variably marked with muddled brown / tan coloration; these areas are: the protibiae, profemoral interior lobe, mesofemoral lobes, and the margins of abdominal segments VII and VIII. Meso- and metacoxae ventrally marked with a dark spot.

Morphology. Head capsule approximately as long as wide, with a vertex that is smooth, lacking granulation (Fig. 13 B ). The posteromedial tubercle is present, singularly lobed, but not very prominent (Fig. 13 B ). Frontal convexity broad and ending in a blunted point; there are several short setae across the surface. Compound eyes slightly protruding from the head capsule, not bulbous, taking up ~ ¼ of the head capsule lateral margins (Fig. 13 B ). Ocelli absent. Antennal fields slightly wider than the first antennomere width.

Antennae consist of ten segments, with the terminal segment the narrowest and approx. the same length as the preceding four segments’ lengths combined (Fig. 13 B ). Antennomeres VIII and IX appear derived from a single segment as they are tightly situated, but have a prominent suture separating them into two, and each segment has a distinct texture, with segment IX a rough, fuzzy texture (like segment X) and segment VIII smoother with sparse setae (like on segment VII; Fig. 13 B ). Antennomeres I – VIII are smooth, and sparsely marked with short setae, the terminal two antennomeres are covered in short, dense setae, giving these segments a fuzzy appearance (Fig. 13 B ).

Thorax. Pronotum with slightly concave anterior margin and lateral margins that anteriorly start wide, angle inward strongly, then for the middle portion are angled more gently, followed by a strong incurve to the posterior margin (Fig. 13 F ). The posterior margin is ~ ½ the width of the anterior margin (Fig. 13 F ). The pronotum anterior margin has a prominent rim, while the lateral and posterior margins are less prominent. The pronotum surface is relatively smooth, with only a prominent pit in the center and a few furrows (Fig. 13 F ). Prosternum, mesosternum, and metanotum are covered throughout by moderately spaced granulation (Fig. 13 D ). Mesoprescutum slightly longer than wide, lateral rims with eight or nine nodes (none particularly prominent; Fig. 13 F ). Mesoprescutum anterior rim prominently raised into a raised, broad sagittal spine (Fig. 13 F ). Mesoprescutum surface smooth except for the slightly raised mesoprescutum sagittal crest marked with variably granulation throughout the length, but only along the sagittal crest; areas lateral to the sagittal crest smooth (Fig. 13 F ). Mesopleurae begin to diverge ~ 1 / 3 of the way along the mesoprescutum, angle prominently away with straight margins (Fig. 13 F ). Mesopleurae lateral margins with six or seven nodes with interspersed granulation throughout, giving the margin a rough textured appearance (Fig. 13 F ). Face of the mesopleura slightly wrinkled, with two notable divots, one on the anterior margin and one near the middle (Fig. 13 F ).

Wings. Tegmina long, reaching onto abdominal segment VIII. Tegmina venation; the subcosta ( Sc) is the first vein in the forewing, running parallel with the margin for the first ½, and then bending and running towards the margin. The subcosta runs for ~ 1 / 3 of the tegmina length. The radius (R) spans the central portion of the forewing with two subparallel branched veins; the first radius ( R 1) branches ~ ¼ of the way through the wing length and terminates slightly proximal to the midline; the radial sector ( Rs) branches ~ 1 / 3 of the way through the wing length and terminates near the distal 1 / 3 of the wing length. There is a weak continuation of the radius following the prominent Rs branching which continues on as a short but distinct R – M crossvein that weakly connects the two veins. The media (M) is bifurcate with both the media anterior ( MA) and media posterior (MP) terminating near to the posterior of the tegmina. There is a weak continuation of the media following the prominent media posterior (MP) branching which continues on as a somewhat long M – Cu crossvein that fades before fully connecting the two veins. The cubitus ( Cu) is also bifurcate, branching near the posterior ¼ of the wing into the cubitus anterior ( CuA) and cubitus posterior ( CuP) which both terminate near the wing apex. The first anal vein ( 1 A) is simple and fuses with the cubitus ~ 1 / 3 of the way through the tegmina length. Alae vestigial, with their apex only just reaching abdominal segment I (~ 6.0 mm long as measured in a paratype).

Abdomen. Abdominal segments II through the anterior 2 / 3 of IV gradually diverging. The posterior 1 / 3 of segment IV through the anterior 2 / 3 of segment VII are gradually and uniformly converging. The posterior 1 / 3 of segment VII is rounded inwards towards segment VIII which like VII starts converging gradually and then rounds inward to segment IX. Segments IX – X have straight, converging margins ending in a broad rounded apex (Fig. 13 H ).

Genitalia. Subgenital plate starts at the anterior margin of tergum VIII, is moderately broad, and extends most of the way onto tergum X. The shape is approximately teardrop-shaped, with the apex a fine point (Fig. 3 E ). Gonapophyses VIII are long and moderately broad, reaching the apex of abdominal tergum X; gonapophyses IX are obstructed from view (Fig. 13 H ). Cerci flat, slightly broadening to the apical ¼, with a slightly granular surface (Fig. 13 H ).

Legs. Profemoral exterior lobe broad, rounded, and obtusely angled, slightly narrower than the width of the interior lobe (Fig. 13 C ). Distal margin of the profemora with three small, finely pointed teeth (Fig. 13 C ). Profemoral interior lobe ~ 3 × as wide as the greatest width of the profemoral shaft, approximately right angled, and marked with three large teeth with looping gaps between them, each gap with a singular smaller tooth (Fig. 13 C ). Mesofemoral lobes significantly broadened on the distal 1 / 3, with the interior lobe greatest width ~ 2 × wider than the mesofemoral shaft width, and the exterior lobe greatest width ~ 1.5 × wider than the mesofemoral shaft width. Mesofemoral exterior lobe with three or four small, distally pointing teeth on the distal 1 / 3 of the lobe. Mesofemoral interior lobe with five small, distally pointing teeth on the distal 1 / 3 of the lobe. Metafemoral interior lobe arcs end to end, with the distal ½ slightly wider than the proximal ½ and marked with five or six serrate teeth on the distal ½ of the lobe. Metafemoral exterior lobe lacks dentation and has a width similar to the metafemoral shaft width. Protibiae exterior has a thin expansion near the middle, less than the width of the protibial shaft (Fig. 13 C ). Protibiae interior lobe spans the entire length of the protibiae and is ~ 2.5 × the width of the protibiae shaft itself. The lobe is roundly triangular with the widest portion on the distal ½. Mesotibiae and metatibiae simple, lacking exterior and interior lobes.

Measurements of holotype female [mm]. Length of body (including cerci and head, excluding antennae) 88.0, antennae 5.8, pronotum 5.9, mesonotum 10.5, length of tegmina 54.7, greatest width of abdomen 32.0, profemora 16.8, mesofemora 15.0, metafemora 18.5, protibiae 11.2, mesotibiae 10.3, metatibiae 15.0.

Measurements of paratype females [mm]. Length of body (including cerci and head, excluding antennae) 73.0–77.0, antennae 5.0–5.5, pronotum 5.2–5.5, mesonotum 9.0–9.5, metanotum 9.0, length of tegmina 46.0–50.0, length of alae 6.0, greatest width of abdomen 28.5–29.0, profemora 14.5–15.0, mesofemora 13.0–14.0, metafemora 15.0–16.0, protibiae 9.0–10.5, mesotibiae 9.0–9.5, metatibiae 13.0–14.5.

Eggs (Figs 12 , 14 ). The lateral flaps and the fused capitular frill are brown; the feather-like pinnae are tan; and the exposed, smooth sides of the egg capsule under the lateral flaps are yellowish / tan in color. The actual egg capsule is notably smaller than the habitus due to the lateral flaps covering the entire lateral surfaces. These lateral flaps are connected to the capsule by a small, stiff section on the posterior of the egg. These lateral flaps are slightly convex and have an irregular, somewhat lumpy surface that lacks pinnae, instead the raised lumpy areas are slightly lighter in color but are smooth in texture. On the microscopical level fine hair-like protrusions cover the surface of the flap (Fig. 14 D ). These lateral flaps are held slightly away from the actual egg capsule, with the anterior margin simple and open, while the lateral flaps lateral margins are curled under slightly, but this rim does not rest on the egg capsule. A thin membrane runs along the inner side of the flap sealing the space between flap and capsule (Fig. 14 H ). The actual egg capsule lateral surface is slightly convex, with a smooth, only slightly lumpy surface (Fig. 14 B ). The dorsal surface has a thin micropylar plate which is ~ ½ the capsule length, but it is situated on the posterior 1 / 2 of the capsule (Fig. 12 A ). Running along each side of the micropylar plate is a continuous line of short, feather-like pinnae. The micropylar plate is thin, really only a slit with the widest portion around the small micropylar cup which is on the posterior ¼ of the capsule (Fig. 12 A ). These feather-like pinnae run fully around the sagittal plane of the egg, so when it is viewed laterally, the pinnae fully surround the capsule, with only the fused capitular frill projecting above the anterior pinnae (Fig. 12 B ). The operculum is ovular, and the outer margin has a fused capitular frill fully surrounding the opercular margin (Fig. 14 C ). This frill is fully fused around the entire margin and is prominently projecting above the flat, smooth surface of the cap, leaving only a narrow, long opening along the top of the egg (Fig. 12 E ). The fused capitular frill is roughly textured, appearing slightly fuzzy. The ventral surface of the egg capsule has the continuous encircling feather-like pinnae coming down from each side from the anterior, these two lines of pinnae gradually draw together until they fuse into one line near the posterior 1 / 3 of the capsule, where they continue on to the posterior (Fig. 12 C ). On the posterior, the encircling feather-like pinnae split around a central pinnae stalk with a feather-like apex (Fig. 12 D ).

Measurements including the extended pinnae [mm].

Length (including operculum expansion): 7.6–7.7; maximum width of capsule when viewed from lateral aspect 4.8–4.9; length of micropylar plate 3.0–3.1.

Etymology.

Patronym; named to honor Frank Hennemann ( Germany). At the time of this writing, Frank has named more than 350 phasmid species, reflecting decades of his dedicated work. Specifically within the phylliids, Frank’s 2009 publication ( Hennemann et al. 2009) was instrumental in sparking the first author’s passion for leaf insects. At the time of its publication, Frank’s work was a major step towards revising the family and served as the foundation for many subsequent works on the group.

Distribution.

At present known from two provinces on Sulawesi, Indonesia (Fig. 2 ). The holotype locality of Bungadidi ( South Sulawesi Province), and the paratype locality of Tiulapolu [= Tipulu] ( Southeast Sulawesi Province).

Remarks.

The eggs of Phyllium hennemanni sp. nov. with their autapomorphic lateral flaps which do not react to humidity and are fixed at a small point on the bottom of the egg, maintain that the lateral flaps are held without touching the egg capsule itself (Fig. 12 ). Currently, the closest relative based on genetic sequences was recovered as Phyllium mamasaense (Fig. 1 ), a species which is sympatric and has adults with very similar morphology (such as femoral lobe shape and serration, genitalia, and coxae coloration). As with other phylliids, interestingly, despite adults being very morphologically similar, the eggs of these two closely related species differ drastically. At present, the adult male Phyllium hennemanni sp. nov. is still unknown, and once identified, may reveal further features for adult morphological differentiation.

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 3. Live Phyllium boislardi sp. nov. holotype female [Coll RC # 21-037] (images courtesy of Edy Bhaskara (Indonesia). A. Dorsal habitus; B. Ventral habitus; C. In situ, dorsolateral view.

Figure 12. Phyllium hennemanni sp. nov. paratype eggs. A, B, C [Coll RC 20-086], D, E [Coll RC 20-087], F, G, H [Coll RC 20-088]. A. Dorsal view; B. Lateral view (dorsum to the left); C. Ventral view; D. Posterior view; E. Opercular (anterior) view; F. Dorsal view with lateral flap opened to expose egg capsule; G. Dorso-lateral view with lateral flap opened to expose egg capsule; H. Dorsal view with lateral flap opened to expose egg capsule and expose inner surface of the lateral flap. Scale bar: 2.0 mm (A, B, C, F, G); 1.0 mm (D, E, H).

Figure 13. Phyllium hennemanni sp. nov. holotype female (ZSM). A. Habitus, dorsal; B. Detail of head and antennae, dorsal (5.0 mm scale bar to the right); C. Front right leg, dorsal; 10.0 mm scale bar; D. Thorax, ventral; E. Terminalia, ventral; F. Habitus, ventral; G. Details of the thorax, dorsal (5.0 mm scale bar below); H. Dorsolateral view of the front legs, head, and thorax; 10.0 mm scale bar. Scale bar 30.0 mm (A, E).

Figure 14. Phyllium hennemanni sp. nov., scanning electron micrographs of a paratype egg [Coll RC 20-088]. A Overview of the egg, dorsal view. B – H. Details of the egg morphology: B. Smooth interior surface: C. Operculum: D. Exterior surface of the lateral flap: E. Interior view of the lateral flap: F. Pinnae; G. Magnification of the inside of the lateral flap; H. Membranous rim of the lateral flap. Scale bars: 2 mm (A), 1 mm (C, E), 10 µm (B), 100 µm (D, G, H), 200 µm (F).