Sadyattes incertus (Redtenbacher, 1906) Hennemann, 2025

Hennemann, Frank H., 2025, A review of Sadyattes Stål, 1875, with the descriptions of six new species from the Philippines (Phasmatodea: Platycraninae: Stephanacridini), Zootaxa 5610 (1), pp. 1-72 : 33-38

Sadyattes incertus (Brunner v. Wattenwyl, 1907) comb. nov.

( Figs. 8–9 , 21M–N )

Phobaeticus incertus Brunner v. Wattenwyl, 1907: 185. HT, ♀ (+ 4 eggs ex abdomen): 3476; Banka v. Mart; Phobaeticus incertus Br., Brunner det.; Holotypus [MNHU]. Brock, 1996: 28. Otte & Brock, 2005: 267. Seow-Choen, 2018: 421, Fig. 328.

Phobaeticus (?) incertus, Hennemann & Conle, 2008: 195 , Figs. 167-168, 252, 395.

= Nearchus grubaueri Brunner v. Wattenwyl, 1907: 186. HT, ♀: Grubauer 1902, Kwala-Kangsar, Perak; Mus. Caes. Vindobon; det. Br. v. W. Pharnacia grubaueri ; Holotypus [NHMW, No. 857]. rev. stat. Brock, 1995: 94. Brock, 1998: 32. [Type data] Seow-Choen, 2000: 35, pl. 92. Bragg, 2001: 393. Brock, 2002: 43. Otte & Brock, 2005: 209. Hennemann & Conle, 2008: 195. [As synonym of Ph. incertus Brunner v. Wattenwyl, 1907]

Phobaeticus grubaueri, Seow-Choen, 2018: 421 , Fig. 329. [Re-established as valid species] Seow-Choen, 2021: 735, Figs. 695-6096. Brock & Büscher, 2022: 554.

Further material:

Peninsular Malaysia: 2 ♀♀: Perak ( Malacca), A. Grubauer leg., B. Jachan vend. 15.XII.1901 [ ZMUH] ; 1 ♂: Perak II.-III.1900 ( Kwala-Kangsar ) B. Jachan vend. 15.VII.1900 [ ZMUH] ; 1 ♂: Malay Penin., Pinding, Tanjong, Hauti, light-House, 26.VIII.1929, F.N. Chasen [ NHMUK] ; 1 ♀: Malacca, Selangor, Ulu Gombak, N.C.E. Miller 1928 [ NHMUK]. Nicobar Islands : 2 ♀♀, 2 eggs: Nicobar Islands, Kamorta Id., I.2001 [coll. PDB, to bedeposited in NHMUK] .

Differentiation. Females ( Figs. 8A–B ) of this large species most closely resemble those of the Bornean S. decoris ( Seow-Choen, 2016) but may be separated by the larger size (body length including subgenital plate> 189.0 mm) and somewhat slender overall shape and limbs, more elongated and notably more flattened head ( Figs. 8C–D ), larger, black and rather spinose than serrate dentations of the extremities, longer subgenital plate, which extends beyond the tip of the abdomen by more than the combined length of the terminal three abdominal terga ( Figs. 8 F-H), and the more distinct praeopercular organ ( Fig. 8H ). The ♂♂ ( Fig. 9A ) most closely resemble those of S. enganensis ( Redtenbacher, 1908) from Peninsular Malaysia, Sumatra and the islands of Enggano and Nias east of Sumatra, S. borrii Stål, 1875 from Java and Sumatra and the Bornean S. annulatus ( Redtenbacher, 1908) . From the two first species they are however easily separable by the much more elongated and flattened head ( Figs. 9B–C ), which is notably longer than the prothorax, and the longer alae, which almost reach to the posterior margin of abdominal segment IV. From enganensis they moreover differ by the slenderer shape, less inflated abdominal segments VIII– IX, as well as the more numerous and acutely pointed black teeth of the mid and hind legs (obtuse and dark green in enganensis ). From borrii these ♂♂ also differ by the dark medio-longitudinal streak of the tegmina and costal region of the alae, not distinctly contrastive pale cream-coloured protarsi, not orange outer ventral carinae of the meso- and metafemora and smaller poculum, which lacks the obtuse basal protrusion seen in borrii ( Fig. 9D ) and much slenderer and elongated, irregularly parallel-sided vomer ( Fig. 9F ; triangular in borrii ). The long alae are shared with annulate, but in this species the alae reach as far back as to abdominal segment V, the head has the vertex weakly convex, the medio-longitudinal carina of the mesosternum is much less pronounced, the meso- and metafemora are plain green except for a blackish apex, and the vomer is more distinctly and gradually tapering towards the terminal point and lacks the median widening seen in incertus . From the known eggs of the genus, those of incertus ( Figs. 21M–N ) most closely resemble eggs of enganensis but differ by the minutely verrucose chorion surface, presence of antero-ventral and dorsal and posteroventral impressions of the chorion, impressed polar-area, lack of the sub-parallel longitudinal dorsal ridges and the much shorter round micropylar plate.

Description. The following description of the previously unknown ♂ is based on the unique example in the collection of ZMUH ( Fig. 9A ). The specimen is fairly complete except for the left mid leg, tips of the metatibiae and both metatarsi as well the right antenna and cerci. The colouration does not seem to be notably diverted by preservation or a preliminary storage in ethanol. Measurements in table 4 below.

♂ ( Fig. 9 ). Large (body length 142.0 mm), form slender for the genus, with an elongated head and fairly long alae that reach about halfway along abdominal segment IV (length 58.0 mm). Meso- and metathorax greyish olive, rest of body essentially drab to ochre, the abdomen becoming brown towards the apex. Meso- and metapleurae with a washed black line along lower margin. Head buff, the genae cream-coloured ventrally and with a faint and rather narrow cream-coloured stripe anteriorly, that roughly runs at upper margin of compound eye ( Figs. 9 B-C). Antennae dark reddish brown. Pronotum slightly russet. Tegmina and alae cream-coloured with a broad blackish medio-longitudinal streak and the anterior margin broadly light cream (possibly whitish when alive); anal fan hyaline with veins pale brown. Abdominal terga V-VII with an elongate washed cream anterolateral marking and the posterior margin broadly black. Terga VIII and IX with a whitish medio-lateral marking. Sterna II-VII with a washed dark medio-longitudinal streak, black posterolateral angles and a bold white posteromedian spot. Poculum brown basally with the remainder straw-coloured ( Fig. 9F ). Profemora green at the base ( Figs. 9B–C ), otherwise irregularly annulated and flecked with dark brown and pale cream, the apex black; protibiae mostly black with four whitish annulae. Meso- and metafemora green throughout the basal half, then gradually becoming buff, then with a washed greyish ochre transverse band and the apex black; meso- and metatibiae black with three broad, dark yellow annulae. All dentations of the limbs black. Basitarsi whitish to pale cream with the apex black.

Head ( Figs. 9B–C ): Elongate-oval, somewhat depressed dorsoventrally, only 1.5x longer than wide, broadest at eyes and notably narrowing towards posterior with the posterior portion of capsule narrowed and somewhat angular in lateral aspect; vertex weakly convex with coronal line weakly and lateral furrow distinctly impressed. Frons with a closely spaced pair of shallow impression between the bases of the antennae. Eyes very large, projecting more than hemispherical and their diameter corresponding to almost 0.7x length of gena. Antennae long and reaching to anterior of abdominal segment IV; scapus slender and slightly narrowed towards base; pedicellus round in cross-section; following joints slightly and irregularly unequal in length and essentially first increasing, then decreasing in length.

Thorax: Pronotum shorter and noticeably narrower than head, basically rectangular in outline and about 1.8x longer than wide, the lateral margins gently convex; the anterior margin somewhat inflated and with a pit near each outer angle of segment; transverse median sulcus distinct, notably impressed, very weakly arched and almost reaching to lateral margins of segment; the medio-longitudinal line slightly indented ( Figs. 9B–C ). Mesothorax very slender, elongate and uniform in diameter with only a slight widening in posterior portion and at anterior margin; almost 7.2x longer than prothorax. Mesonotum with a distinct transverse bulge at anterior margin ( Fig. 9C ) and a weakly indicated medio-longitudinal line. Meso- and metasternum with a fine and low medio-longitudinal carina, which however is quite prominent in the anterior portion of the mesosternum. Tegmina spatulate with basal half gradually narrowing and the central hump shallow and weakly convex. Alae reaching about halfway along abdominal segment IV.

Abdomen: Abdominal segment II and III equal in length, IV–VII slightly gradually decreasing in length but all uniform in diameter; III about 6x and VII only 5x longer than wide. Terga V and VI with an obtusely rounded posteromedian swelling, which is comparatively more pronounced on VI. Sterna II–VII all with a shallow medio-longitudinal carina. Tergum VIII slightly trapezoidal in outline, gradually widening towards the posterior and about half as long as VII; IX just scarcely shorter than VIII and somewhat constricted medially. Anal segment strongly tectate with posterior half distinctly narrowing ( Fig. 9E ); the lateral surfaces slightly gibbose pre-basally; posterior margin somewhat inflated with the ventral surfaces minutely denticulate and distinctly facing each other ( Fig. 9G ). Vomer very elongate, somewhat irregularly digitiform with an up-curved terminal point; the ventral surface with a deep medio-longitudinal furrow and the lateral margins roundly inflated ( Figs. 9F–G ). Phallus enlarged and projecting over posterior margin of poculum ( Figs. 9D–G ). Cerci missing in the unique specimen at hand. Poculum rather small, bowl-shaped with the base moderately bulgy and angular ( Fig. 9D ) and the remainder portion with a distinct medio-longitudinal keel; posterior margin narrowly rounded and hardly reaching posterior of tergum IX ( Fig. 9F ).

Legs: Long, slender and with all carinae rather minutely but acutely dentate; the ventral dentations basically more pronounced that those of the dorsal carinae and the latter somewhat erratic in their distribution. Medioventral carina of meso- and metafemora only supplied with a few very minute spines. Profemora notably longer and mesofemora about as long as head, pro- and mesothorax taken together, metafemora almost reaching posterior margin of abdominal segment V and metatibiae projecting beyond tip of abdomen. Probasitarsi strongly elongated, unarmed and notably longer than all remaining joints taken together. Mesobasitarsi minutely denticulate ventrally and roughly equal in length to combined length of remaining tarsomeres.

Remarks. This species was originally described based on a ♀ from the island of Banka in the Strait of Malacca some kilometres off the north-eastern coast of Sumatra. The unique holotype has provisionally been preserved in spirits, why it has lost its natural colours and has most of the body but the abdomen in particular considerably shrivelled. The notably larger holotype ♀ of grubaueri from Kuala Kangsar, Perak, Peninsular Malaysia in the collection of NHMW is very well preserved. While an egg could be removed from the ovipositor of the holotype of grubaueri , some eggs were extracted from the abdomen of the holotype of incertus in order to provide certainty about its taxonomic position. Since, nor the ♀♀ neither the eggs provided any significant differences from each other Hennemann & Conle (2008: 195) synonymised grubaueri under incertus . This was doubted by Seow-Choen (2018: 421), who re-established grubaueri as a valid species, and postulated that the holotype of incertus was smaller, slenderer and has the posterior margin of abdominal sterna V–VII rounded and slightly raised posteromedially, whereas it is medially incised and bi-lobed in the holotype of grubaueri as well as further specimens the author had examined from Pahang and Johor, Peninsular Malaysia. Re-examination of the holotype of incertus and comparison with the Malayan ♀♀ listed above and taking the shrivelled condition of the type of incertus into account leaves no doubt incertus and grubaueri are the same species. The difference in size is not unusual between specimens of an individual species from the mainland and circumjacent islands, and within an expectable range. As already stated by Hennemann & Conle (2008: 197) also the eggs of both taxa do not show any significant differences that would separate them as distinct species. Therefore, Redtenbacher’s grubaueri is here re-synonymised with incertus (rev. stat.).

Seow-Choen (2021: 735) assumed it was highly likely that grubaueri was the opposite sex of Phobaeticus pinnipes ( Redtenbacher, 1908) , however these two species are not closely related, since the latter belongs in Clitumninae : Pharnaciini and is not a member of Platycraninae : Stephanacridini . Moreover, the collection of ZMUH houses a ♂ from Kuala-Kangsar, Perak, Peninsular Malaysia, the type-locality of grubaueri , which undoubtedly represents the previously unknown ♂ of the present species. In addition to this ♂ there is another Malayan example in the collection of NHMUK. A description of the ♂ of incertus is here presented based on these two specimens and detailed illustrations of both sexes are presented. Hennemann & Conle (2008: 197, Figs. 167–168) have provided a description and illustrations of the egg but a photographic documentation of the eggs is here presented to accomplish the treatment of this species.

Distribution. Banka Island (northeast off Sumatra) [MNHU – type-locality]. Peninsular Malaysia: Perak (Kuala Kangsar [NHMW, ZMHU]); Selangor: (Ulu Gombak [NHMUK]); Penang (Tanjong [NHMUK]); Pahang [ Seow-Choen, 2018: 421]; Johor [ Seow-Choen, 2018: 421]. Nicobar Islands: Kamorta Island [PDB (NHMUK)].

Figures

FIGURE 8. Sadyattes incertus (Redtenbacher, 1906) comb. nov. ♀ from Peninsular Malaysia, Perak [ZMUH]: A. Habitus, dorsal view; B. Habitus, dorsolateral view; C. Head and prothorax, lateral view; D. Head and prothorax, dorsal view; E. Mesofemur in ventral view; F. Terminalia in ventral view; G. Terminalia in dorsal view; H. Terminalia in lateral view.

FIGURE 9. Sadyattes incertus (Redtenbacher, 1906) comb. nov. ♂ from Peninsular Malaysia, Kuala Kangsar [ZMUH]: A. Habitus, dorsolateral view; B. Head and prothorax, dorsal view; C. Head and prothorax, lateral view; D. Terminalia in lateral view; E. Terminalia in ventral view; F. Terminalia in dorsal view; G. Two terminal abdominal segments in ventro-caudal view. (Cerci missing). Pha = phallus, TP =thorn pads

FIGURE 21. Eggs of Sadyattes spp., dorsal view (left) and lateral view with micropylar plate at left hand side (right): A–B. S. mindanaense sp. nov. (paratype); C–D. S. fallax (Brunner v. Wattenwyl, 1907) comb. nov.; E–F. S. feruloides (Westwood, 1859) comb. nov.; G–H. S. leytensis (Zompro, 1997) comb. nov.; I–J. Sadyattes matipuno sp. nov. (paratype); K–L. S. decoris (Seow-Choen, 2016) comb. nov. [© Francis Seow-Choen]; M–N. S. incertus (Redtenbacher, 1906) comb. nov. from ovipositor of holotype of synonym Nearchus grubaueri Redtenbacher, 1908 [© NHMW, Harald Bruckner]; O–P. S. enganensis (Redtenbacher, 1908) [© Francis Seow-Choen].