Nesiophasma davisdamaledoi, Hennemann & Damastra & Tirant, 2025

Hennemann, Frank H., Damastra, Garda Bagus & Tirant, Stéphane Le, 2025, Nesiophasma davisdamaledoi sp. nov. - a new stick insect from the island of Sumba, Indonesia (Insecta: Phasmatodea), Zootaxa 5660 (2), pp. 194-210 : 198-206

publication ID	https://doi.org/10.11646/zootaxa.5660.2.2
publication LSID	lsid:zoobank.org:pub:03C35BB7-8822-43DF-AAE2-CFE895D39BBA
persistent identifier	https://treatment.plazi.org/id/263887FF-7B79-FF99-14A8-FAB3FA8DFB14
treatment provided by	Plazi
scientific name	Nesiophasma davisdamaledoi
status	sp. nov.

Treatment

Nesiophasma davisdamaledoi sp. nov.

urn:lsid:zoobank.org:act:15C2D5B4-23FD-4B92-A5AF-775C18E0FEDB

( Figs. 1–8 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 )

Holotype, ♀: Indonesia, Province East Nusa Tenggara, Sumba Island, East Sumba Regency (Kabupaten Sumba Timur), Kanatang District , Temu , 9°56'49"S, 120° 24'13"E, semi-arid deciduous forest, leg. Davis Marthin Damaledo 20.VIII.2023 [ MZB]. GoogleMaps

Paratype, 3 eggs: laid by holotype [ MZB] .

Paratype, 3 eggs: laid by holotype [coll. FH, No. 1485-E1].

Paratype, 1 ♂, 1 ♀, 5 eggs: ex Zucht F. Hennemann 2024 (F1-Gen.), Herkunft: Indonesien, Prov. East Nusa Tenggara, Sumba Isl., East Sumba Regency , Kanatang Dist. , Temu , 9°56'49"S, 120° 24'13"E, leg. D.M. Damaledo 20.VIII.2023 [ex coll. FH, MZB] GoogleMaps .

Paratypes, 9 ♂♂, 5 ♀♀, 50 eggs: ex Zucht F. Hennemann 2024 (F1-Gen.), Herkunft Indonesien, Prov. East Nusa Tenggara, Sumba Isl., East Sumba Regency , Kanatang Dist. , Temu , 9°56'49"S, 120° 24'13"E, leg. D.M. Damaledo 20.VIII.2023 [coll. FH, No’s 1485-1 to 14 & E2] GoogleMaps .

Paratypes, 10 ♀♀, 3 ♂♂: ex Zucht F. Hennemann 2024 (F2-Gen.), Herkunft Indonesien, Prov. East Nusa Tenggara, Sumba Isl., East Sumba Regency , Kapatang Dist. , Temu , 9°56'49"S, 120° 24'13"E, leg. D.M. Damaledo 20.VIII.2023 [coll. FH, No’s 1485-15 to 27] GoogleMaps .

Paratypes, 2 ♀♀, 2 ♂♂: ex Zucht T . Bollens 2024 (F2-Gen.), Herkunft Indonesien, Prov. East Nusa Tenggara, Sumba Isl. , East Sumba Regency , Kapatang Dist. , Temu , 9°56'49"S, 120° 24'13"E, leg. D.M. Damaledo 20.VIII.2023 [ RBINS] GoogleMaps .

Differentiation. This rather small species is morphologically closest to the second known Nusa Tenggara species, the Timorese N. sobesonbaii Hennemann et al., 2023 . Females share with this species the general shape and appearance as well as the short gonapophysis VIII, which just slightly projects beyond the anal segment ( Fig. 2K View FIGURE 2 ). They are however easily distinguishable by the notably smaller size (body length below 170.0 mm), lack of the red longitudinal stripe of the mesopleurae seen in sobesonbaii ( Fig. 8D View FIGURE 8 ), distinctively black lower portion of the genae ( Figs. 2D–E View FIGURE 2 ), generally smaller and more numerous teeth and spines of the extremities, spinose medioventral carina of the meso- and metafemora ( Fig. 2L View FIGURE 2 ; unarmed in sobesonbaii ), narrower posteromedian incision and less rounded lobes of the posterior margin of the anal segment ( Fig. 2H View FIGURE 2 ), and lack of the distinctive black marking in front of the comparatively smaller praeopercular organ ( Figs. 2I–J View FIGURE 2 ). The difference in size is less distinct in ♂♂ if compared to sobesonbaii , but these ♂♂ are readily separated by the distinctive and more vibrant colouration, being green with yellow along the lateral margins of the dorsal and ventral body segments and having a black longitudinal line along the meso- and metapleurae ( Fig. 8B View FIGURE 8 ; body ochre with meso- and metapleurae green in sobesonbaii ). Moreover, ♂♂ of davisdamaledoi sp. nov. differ by the black lower portion of the genae ( Fig. 3C View FIGURE 3 ), spinulose dorsal carinae and spinose medioventral carina of the meso- and metafemora, lacking the notably enlarged and prominent apical spine on the two exterior ventral carinae of the meso- and metafemora ( Fig. 3H View FIGURE 3 ), less indented posterior margin of the anal segment ( Fig. 3E View FIGURE 3 ), not in-curved and hook-like apex of the cerci ( Figs. 3E–F View FIGURE 3 ) and broader base of the vomer ( Fig. 3F View FIGURE 3 ; vomer elongated and gradually tapering in sobesonbaii ). The eggs ( Figs. 4A–B View FIGURE 4 ) clearly differ from those of sobesonbaii by the slightly smaller dimensions, much less sculptured capsule surface, which lacks the distinct impressions seen in sobesonbaii , as well as the more elongated polar end of the micropylar plate and conical rather than peg-shaped capitulum.

Etymology. This new species is named after Davis Marthin Damaledo (Kupang, Timor, East Nusa Tenggara), who discovered it on the island of Sumba in August 2023.

Description. The following descriptions are based on all examined type-specimens.

♀ ( Figs. View FIGURE 1 1–A -E, 2 View FIGURE 2 , 7 View FIGURE 7 ). Fairly small (body length including subgenital plate 131.0–167.0 mm) and slender for the genus with a long and lanceolate subgenital plate. General colour various shades of green (e. g. holotype, Figs. 1A– B View FIGURE 1 ), fawn, drab or brown ( Fig. 1E View FIGURE 1 ) and to a variable degree flecked with darker and lighter tones, more rarely with notable darker mottling or fawn to brown with some green mottling along the later body surfaces; green specimens usually more uniform in colour. Occasionally, there is a faint orangey or reddish medio-longitudinal stripe running along most of the dorsal body surface ( Fig. 2O View FIGURE 2 ). Head with a black marking antero-dorsally of compound eye and with a faintly indicated dark postocular marking. Pronotum with a pair of closely spaced converging black stripes in anterior half and a pair of more widely spaced posteriorly out-curved, longitudinal black stripes in posterior half. Praeopercular organ reddish brown ( Figs. 2I–J View FIGURE 2 ), cerci and gonapophyses ochre ( Fig. 2K View FIGURE 2 ). In green specimens the dorsal surface of the subgenital plate ochraceous brown. Meso- and metafemora and tibiae with two faintly indicated pale transverse bands ( Fig. 2L View FIGURE 2 ). All teeth of the limbs tipped with dark reddish brown in brown specimens or very dark green to black in green individuals. Antennae ochre to drab (the two basal joints green in green specimens) and the basal six joints with a black medio-longitudinal dorsal stripe and a similar blackish medio-longitudinal stripe almost along entire ventral surface of antennae.

Head ( Figs. 2A–E View FIGURE 2 ): Ovoid, with vertex gently rounded and smooth, broadest slightly behind the eyes and gradually narrowing towards the posterior; 1.3x longer than wide. Between the bases of antennae with a deep, transverse impression and the area posteriorly of the impression slightly swollen. Eyes small, subcircular, their diameter contained about 2.4x in the length of the gena.Antennae reaching to posterior margin of median segment (= abdominal tergum I) and the antennomeres gradually decreasing in length towards apex of antennae. Scapus roundly rectangular in dorsal aspect, compressed dorsoventrally and about 1.7x longer than wide, pedicellus cylindrical, III slightly narrowing towards apex and almost 2x longer than pedicellus.

Thorax: Pronotum noticeably shorter and somewhat narrower than head, slightly trapezoidal in outline with the posterior margin somewhat broader than anterior margin; lateral margins weakly and the anterior margin distinctly concave; a fine longitudinal median furrow present throughout the entire length; transverse median sulcus somewhat displaced towards the anterior, shallow, short and weakly arched ( Figs. 2 A–C View FIGURE 2 ). Mesothorax about 5.8x longer than prothorax and on average 5.8x longer than wide, slightly narrowed anteriorly and weakly widening towards the posterior, but without any indication of a median swelling like in other congenerics. Metanotum slightly more than half as long as mesonotum, rectangular and 3x longer than wide. Meso- and metasternum simple.

Abdomen: Abdomen considerably longer than head and thorax combined. Median segment slightly trapezoidal and somewhat more than one-third the length of metanotum ( Fig. 2O View FIGURE 2 ). Abdominal segments II – V slightly increasing in length, V and VI roughly equal in length and VII about as long as IV; II 1.5x and VI 2x longer than wide. III slightly wider than all following segments, which are very gently but gradually narrowing. Sterna II–VII smooth but with a shallow longitudinal carina close to lateral margins. Praeopercular organ formed by a small median protuberance with a posterior invagination near the posterior margin of sternum VII ( Figs. 2I–J View FIGURE 2 ). Tergum VIII about 1.5x longer than wide and half as long as VII, IX slightly transverse. Anal segment (= tergum X) with the lateral margins roundly excavated near the base of the cerci ( Figs. 2F–G View FIGURE 2 ), the posterior margin distinctly bi-lobed with a deep and slit-like median incision ( Figs. 2H View FIGURE 2 ). Cerci conical and strongly tapered towards a narrow tip and not reaching the apex of the anal segment. Gonapophysis VIII fairly short for the genus and just scarcely projecting beyond the anal segment ( Figs. 2F, K View FIGURE 2 ); gently up-curved and inner surface with a deep longitudinal furrow. Subgenital plate long, lanceolate, with basal portion strongly bulging and tub-like, more or less down-curved in the apical half ( Figs. 2F–K View FIGURE 2 ) and gradually narrowing towards a narrow but obtuse tip ( Figs. 2H–J View FIGURE 2 ); projecting over apex of abdomen by almost the combined length of abdominal terga VII–X.

Legs: All moderately long and moderately stocky, profemora almost as long as head, pro- and mesothorax combined, mesofemora notably longer than metathorax, metafemora projecting over posterior margin of abdominal segment IV and metatarsi roughly reaching the tip of the abdomen. All carinae rather minutely but densely dentate teeth of tibiae smaller than those of femora but more numerous and mid and hind legs with dorsal teeth smaller than ventral teeth. The two apical teeth of the two exterior ventral carinae of meso- and metafemora slightly enlarged. Posterodorsal carina of profemora coarsely serrate with the teeth slightly decreasing in size towards the apex. Medioventral carina of all femora indistinct and spinose ( Figs. 2L View FIGURE 2 ). Basitarsi with dorsal carina just slightly deflexed and rounded in apical half, the ventral carinae denticulated. Probasitarsus as long as proceeding tarsomeres taken together, meso- and metabasitarsus somewhat shorter than remaining tarsomeres combined.

♂ ( Figs. 1 View FIGURE 1 F–G, 3 View FIGURE 3 , 8 View FIGURE 8 ). Fairly small (body length 88.5–105.0 mm) but very colourful for the genus, shape moderately slender. Entire body smooth and shiny. General colour of body mid to dark green with a slight bluish hue, the thorax more intense in colour and the terminal abdominal segments with an increasingly greyish wash. Lateral margins of all dorsal and ventral body segments apple green and then with a dark yellow stripe which is broadest in the pre-posterior portions of the meso- and metanotum ( Fig. 8B View FIGURE 8 ). Meso- and metapleurae with a fine longitudinal black line, that widens to a triangular black marking just before coxae ( Fig. 8B View FIGURE 8 ). Head pinkish cream ( Figs. 3A–B View FIGURE 3 ) with the lower portions of genae black ( Fig. 3C View FIGURE 3 ); frons with the same black spot in front of compound eye as in ♀♀. Prothorax mostly orange with the same black pattern seen in the ♀♀ ( Fig. 3B View FIGURE 3 ). Coxae green with black markings. Legs plain green with all teeth dark green and tipped black ( Fig. 3H View FIGURE 3 ); the front legs as well as meso- and metatibiae however with a slight olive wash; knees orangey in colour. Antennae coloured basically as in ♀♀, but the black longitudinal dorsal and ventral streaks broader.

Head ( Figs. 3A–C View FIGURE 3 ): Elongate-ovoid, almost 1.4x longer than wide and broadest just behind the eyes, genae narrowing, the vertex gently rounded and wholly smooth. Frons between the bases of antennae with two small but distinct impressions that are connected by a transverse groove; the area posterior of the impression shallowly inflated. Eyes large, circular in outline and projecting more than hemispherical, their diameter contained a little more than 1.5x in length of gena. Antennae long and filiform, reaching to the middle of abdominal segment V. Basal three segments essentially as in ♀♀ but relatively more elongate and scapus 1.75x longer than wide.

Thorax: Pronotum basically as in ♀, but slenderer and roughly 1.9x longer than wide ( Figs. 3A–B View FIGURE 3 ); the anterior margin more distinctly indented and widely V-shaped, the transverse median sulcus almost straight. Mesothorax slender and elongate, slightly widened posteriorly, about 7.8x longer than pronotum and almost 13x longer than wide; just weakly widened posteriorly. Metanotum approximately half the length of mesothorax almost uniform in diameter and roughly 6.4x longer than wide. Mesosternum very weakly tectate medio-longitudinally. Tegmina vestigial (length <0.5 mm).

Abdomen: Abdomen excluding median segment considerably longer than head and thorax combined. Median segment (= abdominal tergum I) trapezoidal in outline and noticeably narrowed towards the anterior with posterior margin about twice the width of anterior margin, about 4x longer than width at anterior margin and scarcely 0.4x the length of metanotum ( Fig. 3G View FIGURE 3 ). Segments II – V roughly uniform in length and about 4.2x longer than wide, II about 1.7x longer than median segment and VI–VII slightly decreasing in length; all weakly narrowed medially. Sterna II – VII smooth. Tergum VIII a little more than half as long as VII, strongly inflated and trapezoidal in outline, being gradually widened towards the posterior with the posterior margin 2x wider than anterior margin. IX slightly shorter than VIII, narrowed towards the posterior and with anterior margin somewhat broader than posterior margin. Anal segment (= tergum X) scarcely longer than wide, notably shorter than IX and gently narrowing toward the posterior and with the lateral surfaces slightly convex sub-basally; the posterior margin broadly but shallowly concave and the outer corners obtusely rounded ( Fig. 3E View FIGURE 3 ). Ventrally the posterior margin is densely set with small blackish denticles (= thorn pads; Figs. 3E–F View FIGURE 3 ). Poculum small and moderately convex, cucullate ( Fig. 3D View FIGURE 3 ) with the posterior margin broadly rounded and somewhat labiate with a small median indention; almost reaching to posterior of tergum IX ( Figs. 3D–E View FIGURE 3 ). Vomer basically heart-shaped with base rather broad and somewhat rounded and the apical half distinctly tapering to form a fairly long, slender, acutely pointed and gently up-curved terminal hook; the ventral surface is smooth and with a shallow medio-longitudinal furrow on the median portion ( Fig. 3F View FIGURE 3 ). Cerci obtuse, almost round in cross-section, gently in-curved with the apex obtusely rounded; notably projecting beyond posterior margin of anal segment ( Figs. 3D–E View FIGURE 3 ).

Legs: All long and slender, with all carinae fairly minutely but constantly dentate; teeth less distinct but more numerous on the tibiae and on all dorsal carinae. Profemora considerably longer than head, pro- and mesothorax combined, mesofemora about as long as pro- and mesothorax combined, metafemora reaching halfway along abdominal segment V and metatibiae projecting strongly over apex of abdomen. Medioventral carina of all femora weakly developed but spinulose. Tarsi elongate and slender (probasitarsus in particular), probasitarsus longer than remaining tarsomeres taken together, meso- and metabasitarsi longer than following three tarsomeres combined and with a few small teeth on the two exterior ventral carinae.

Variability. Both sexes show only slight variability in size as well as the development and number of teeth on the extremities. While ♂♂ show no chromatic variation, ♀♀ occur in a green and a brown colour form. Captive breeding corroborated that drab or brown specimens occur notably rarer than the usual green form. In captivity in Europe three of the six ♀♀ of the F1-generation were green with the other two individuals fawn and greyish mid brown. A seventh ♀ was light apple green with a brown prothorax and brown speckles in the posterior portions of the meso- and metathorax. The specimen however died shortly after the final ecdysis and was not preserved. The ratio of green and brown among the eleven preserved F2-generation ♀♀ in coll. FH is somewhat different to that in the F1-generation, with brown or drab specimens comparatively more numerous. While five specimens are different tones of green, ranging from light green to almost olive, there are three mid brown specimens, one light brown specimen, and two that are ochre to drab and unevenly flecked with darker brown. Two of the green specimens, one from the F1 and one from the F2-generation has a faint and weakly defined pinkish medio-longitudinal streak running along most of the dorsal body surface.

Nymphs. Newly emerged nymphs ( Fig. 4C View FIGURE 4 ) are slender with very long legs and have a body length of 17 mm. Their body is yellowish apple green in colour with only the anal segment and lateral portions of the pronotum brown. The genae bear a postocular cluster of dark brown postocular speckles. All legs are dark brown and all over flecked or dotted with pale grey to white; these speckles composed to form two faint transverse bands on meso- and metafemora and tibiae. Most of basitarsi whitish with only the apex brown. Antennae annulated with the same colours seen in the legs. Eyes dark grey with brown speckles. Later instars of both sexes are moderate to dark green or more rarely ochre to brown throughout the entire nymphal development with the subgenital plate always brown. The sexes can be distinguished from the 3 rd instar on.

Egg ( Figs. 4A–B View FIGURE 4 ). Fairly small, general colour light greyish drab to buff; the raised portions of the capsule somewhat darker than the lower areas. Capsule elongate-ovoid, barrel-shaped about 2x longer than wide, the anterior portion somewhat narrowed and the ventral surface as well as the lower portion of the dorsal surface below the micropylar plate with a shallow and obtuse longitudinal bulge. Capsule surface minutely and sparsely granulose and unevenly rugulose with the rather shallow rugulae forming an irregular meshwork, which is most pronounced around the micropylar plate.An indicated rim of indentions is seen below the anterior margin and the opercular collar is slightly inflated. Polar area weakly indented and somewhat darker grey in colour. Micropylar plate spearheadshaped, notably less than half the length of capsule with lower portion strongly narrowed, the inner portion dark grey in colour and the bulging outer margin of a slightly lighter tone. Micropylar cup distinct, knob-shaped, and placed just above the constricted posterior portion of the capsule. Median line almost reaching about half way to polar area and on both sides bordered by an unevenly shaped longitudinal bulge. Operculum almost circular, flat and with the outer margin weakly swollen; greyish/mid brown. Capitulum an irregular conical projection with a prominent basal constriction that projects by about one-sixth the length of the capsule and is star-shaped in diameter with distinct lengthwise ridges and invaginations; colour reddish to orangey brown. Measurements [mm]: Overall length 4.0–4.1, length 3.3–3.4, width 1.7–1.8, height 1.9–2.0, length of micropylar plate 1.3.

Biology & breeding. The holotype of this new species was found on a feral guava tree ( Psidium guajava , Myrtaceae ) in semi-arid lowland deciduous forest along a river bed in the Kanatang District of East Sumba Island, East Nusa Tenggara Province ( Fig. 5 View FIGURE 5 ). Guava is not a native plant species in Southeast Asia, however until N. davisdamaledoi is found on any other native plant species, the true native host plant(s) remain unknown. In addition to guava several other plants have been accepted as food in captivity in Indonesia, including mango ( Mangifera indica , Anarcadiaceae), cashew ( Anarcadium occidentale , Anarcadiaceae), eucalyptus ( Eucalyptus alba & E. urophylla , Myrtaceae ) and Acacia spp. ( Fabaceae ). From these only the acacias are truly native to Sumba and likely to be a natural host plant of N. davisdamaledoi .

In addition to captive breeding in Timor by Davis M. Damaledo, eggs laid by the holotype were also sent to the first author for breeding purposes in order to obtain information on the life-cycle, behaviour, incubation time of eggs, developmental periods of nymphs and also intraspecific variability. Breeding of the F1 and F2 generations has proven pretty easy in Europe, where oak ( Quercus spp. , Fagaceae ), bramble ( Rubus fruticosus , Rosaceae ), hazel ( Corylus avellana , Betulaceae ), salal ( Gaultheria shallon , Ericaceae ) and eucalyptus ( Eucalyptus spp. Myrtaceae ) are readily accepted as alternative food plants by the newly hatched nymphs and throughout the entire life cycle. This species possesses a remarkably fast development for a phasmid of that size, with the entire life-cycle from egg to egg taking less than seven months at average temperatures of 22–25°C. The developmental periods are most certainly even shorter at the higher temperatures in its natural habitat, why the natural life-cycle can be estimated to be around six months on the island of Sumba. At 22–25°C in the laboratory eggs hatch after 14 weeks and the hatching rates haven proven to be fairly high at about 80% in the first two generations. Nymphs are very fast growing in the laboratory conditions and reach maturity after only 12–14 weeks, with ♂♂ usually developing slightly faster than ♀♀. The mortality rate of the hatchlings has proven to be very low in the F1 generation, with about 90% of the individuals reaching the second instar. There however were a few losses throughout the proceeding nymphal development and four of the ♀♀ either died at the penultimate instar or didn’t continue to feed after the final ecdysis. A moderately large and well-ventilated cage and medium humidity of 60–80% with a daily spray of water have proven to provide appropriate climatic conditions for a good nymphal development and successful ecdysis.

Like in other congenerics (Hennemann et al., 2023) eggs are simply flicked away singularly by the adult ♀♀ and an average of five eggs is produced per day and ♀. Adults and nymphs are very difficult to handle because they will frequently drop to the ground if disturbed and behave very hectical, which includes rolling on the ground and floundering wildly. Only after a while of maintaining this awkward behaviour they either remain motionless or quickly walk away to climb the next host plant. Nymphs especially shed limbs easily if a leg is grasped by a predator or the uncareful breeder.

Distribution ( Fig. 5 View FIGURE 5 ). Endemic to the Island of Sumba and so far, only known from two localities.