Phobaeticus hypharpax ( Westwood, 1859 )

Hennemann, Frank H. & Conle, Oskar V., 2008, Revision of Oriental Phasmatodea: The tribe Pharnaciini Günther, 1953, including the description of the world's longest insect, and a survey of the family Phasmatidae Gray, 1835 with keys to the subfamilies and tribes (Phasmatodea: " Anareolatae ": Phasmatidae), Zootaxa 1906, pp. 1-316 : 144-149

Phobaeticus hypharpax ( Westwood, 1859)

(Figs. 77, 124, 177–178, 246–248, 275, 334–335, 339, 381)

Phibalosoma hypharpax Westwood, 1859: 75 , pl. 13: 6, 6a–b. HT, ♂: Holotype; Phibalosoma Hypharpax , Westw Ceylon (BMNH).

Kaup, 1871a: 19, pl. 1: 11. [Description and illustration of egg]

Kaup, 1871b: 37. [Description of ♀]

Pharnacia hypharpax, Redtenbacher, 1908: 453 .

Phobaeticus hypharpax, Brock, 1996: 28 .

Otte & Brock, 2005: 268.

Tirachoidea hypharpax, Brunner v. Wattenwyl, 1893: 83.

Kirby, 1904a: 360.

Cladoxerus acanthopus var. (?), de Haan, 1842: 132.

Pharnacia spectabilis Redtenbacher, 1908: 453 . HT, ♀: Coll. Br. v. W., Ceylon, Dr. Haly; det. Br. v. W. Pharnacia spec- tabilis; 17.226; Ph. spectabilis Redt. (NHMW, No. 863). syn. nov.

Phobaeticus spectabilis, Brock, 1996: 30 .

Otte & Brock, 2005: 270.

Further material: [14 ♀♀, 7 ♂♂, 1 ♀ (nymph), 1 egg]:

SRI LANKA:

1 ♂: Coll. Br. v. W., Ceylon, Dr. Haly; det. Br. v. W. Pharnacia hypharpax ; 16.664 ( NHMW, No. 864) ; 1 ♀: Coll. Br. v. W., Ceylon, Dr. Haly; det. Br. v. W. Pharnacia hypharpax ; 17.228 ( NHMW, No. 864) ; 1 ♂: Coll. Br. v. W. Ceylon, Makwood ; 16.101 ( NHMW, No. 864) ; 1 ♂, 1 ♀ + 1 egg (ex ovipositor): Ceylon , Racuapura, III.1912, Pres. by Imp. Pur. Ent. Brit. Mus. 1922-468, leg. E.E. Green ( BMNH) ; 1 ♀: Ceylon, pres. by Mr. Salvaga c/o Cox & co., Charing Cross, 1915- 24. ( BMNH) ; 1 ♀ (nymph): Kandy , Sept.1914, leg., Whittle Coll., 1922-79 ( BMNH) ; 1 ♀: Archabald Coll. B. M. 1926- 391, Karen Hill , THDG, Tracts, June 1923 ( BMNH) ; 1 ♂: Ceylon ( MHNG) ; 1 ♀: Ceylon ( HLDH) ; 2 ♀♀, 1 ♂: Ceylon , Worms ( SMFM) ; 1 ♀ (nymph): Ceylon, Worms ; 8 ( SMFM) ; 1 ♀: Ceylon 1912, A. Hansen ( SMFM) ; 1 ♀: Ceylon, H.V. Hilprecht; Pharnacia spectabilis Redt. (ANSP) ; 1 ♂: Ceylon ( ANSP) , 1 ♀: Ceylon ( SNMB) .

SOUTH INDIA:

1 ♀: S. India: Coorg, Mercara. 9-XI.1934, Maj. F.C. Fraser; Walking stick insect Ballquatrie, Mercara, Coorg, 9.XI.24 ( BMNH) .

NO DATA:

1 ♀: ( BMNH) ; 1 ♀, 1 ♂: ( SMFM) .

Diagnosis: ♀♀ are characteristic for the sparse but very broad and prominent serrations of the anterodorsal carina of the profemora and unarmed medioventral carina of the meso- and metafemora. Closely related the second Sri Lankan species Ph. lobulatus ( Carl, 1913) comb. nov. and Ph. sinetyi Brunner v. Wattenwyl, 1907 from the Madras Province of southeastern India. ♀♀ differ from those of Ph. lobulatus by: the larger size; more rounded and less broadened lateral lobes of tergite VII; tergite VIII being shorter than IX and X combined (Fig. 246); unarmed mesopleurae; much longer and filiform antennae and different armature of the legs. From Ph. sinetyi it is distinguished by: the comparatively more slender body; longer median segment and smooth medioventral carina of the meso- and metafemora of both sexes, as well as the more prominent dorsal serrations and distinctly smaller teeth of the posteroventral carina of the profemora (Fig. 339), different armature of the mid and hind legs (Figs. 334–335) and broader lateral lobes of abdominal tergite VII of ♀♀. ♂♂ clearly differ by: the dentate posteroventral carina of the profemora; presence of tegmina and well developed alae and more elongate, slender semi-tergites of the anal segment (Fig. 248). Eggs differ from those of Ph. sinetyi by the strongly sculptured, rugulose and wrinkled capsule surface and relatively larger micropylar plate (Figs. 177–178).

Etymology: The derivation of the specific name hypharpax is doubtful. It may be a combination of the Latin “ harpax ” (= rapacious) and the Greek prefix “ hypo- ” (= under) meaning as much as “not rapacious”. Another possibility may be it was derived from Hypharpax MacLeay, 1825 a genus of Australasian Coleoptera ( Carabidae : Harpalinae ).

Description: ♀♀ ( Fig. 124): Long to very long (body length 185.0–236.0 mm) and slender species (maximum body width ± 6.0 mm) with a short subgenital plate and prominent dorsal serrations on the profemora. Degree of leg armature variable (→ below). General colour of body and legs mid to dark ochracheous or greyish brown, either plain or to a variable degree furnished with numerous irregular paler markings and speckles; slightly shiny dorsally. Head of paler colour than rest of body. Meso- and metafemora with more or less distinct pale transverse bands and with a broad whitish or greyish band at the apex. Armature of legs dark brown to black. Eyes dark reddish brown. Antennae dark greyish brown, scapus often blackish dorsally.

Head: Elongate, oval, almost 2x longer than wide, slightly narrowing towards the posterior and with a faint impressed coronal-line; vertex smooth and very gently convex. Posterior portion with two longitudinal lateral impressions and each side of the coronal-line. Between the eyes with a slightly raised, smooth, Cshaped area. Eyes small, moderately convex and with anterior margin slightly angled; length contained about 3.5x in that of cheek. Antennae rather short and reaching about 2/5 the length along mesonotum. Scapus slightly curved, dorsoventrally flattened and about 2.5x longer than wide. Pedicellus ¼ the length of scapus, cylindrical.

Thorax: Pronotum shorter and distinctly narrower than head, 1.3x longer than wide, posterior margin broader than anterior margin. Median transverse depression distinct, widely V-shaped but not reaching lateral margins of segment. Mesothorax constricted anteriorly and 2.3–2.5x longer than head and pronotum combined. Mesonotum with a very faint slightly darker longitudinal median line (in most cases only visible in posterior portion of segment). Metanotum slightly more than 1/3 the length of mesonotum, about 2x longer than wide, rectangular. Meso- and metasternum with a very faint longitudinal median carina.

Abdomen: Median segment slightly shorter than metanotum, anterior margin gently rounded. Segment II shorter than median segment and III–VII. III–VI very slightly increasing in length, and 2.6–2.8x longer than wide. Tergites V and VI with scale-like posteromedian tubercle (more prominent on V). VII about 5/6 the length of VI, lateral margins with a rounded posterior lobe of variable size. This lobe with the posterior margin ± acutely angulate to triangular and sometimes slightly projecting over posterior margin of the segment (Fig. 275). Praeopercular organ indistinct and represented by a pair of short, roundly raised carinae at posterior margin of sternum VII. Tergite VIII distinctly narrower than previous, almost 3x longer than wide, strongly convex and constricted medially. IX about half the length of VIII, indistinctly longer than wide, strongly convex. Anal segment 1.5x longer than IX with fine median carina and a widely triangular indention at posterior margin, outer angles acutely triangular (Fig. 247). Supraanal plate very small strongly keeled and rounded. Cerci small, oval in cross section, finely sethose and slightly projecting over anal segment. Gonapophyses yellowish brown, filiform, up-curving but not reaching apex of anal segment. Subgenital plate longitudinally keeled, boat-like and slightly projecting over posterior margin of anal segment (Fig. 246).

Legs: All long and slender, profemora a little longer than combined length of pro- and mesonotum, mesofemora slightly shorter than mesothorax, metafemora projecting over posterior margin of abdominal segment IV and metatarsi just not reaching apex of abdomen. Anterodorsal carina of profemora with 8–10 prominent, broad and ± wave-like serrations which decrease in size towards the apex of femur (Fig. 339). Posterodorsal carina occasionally with 1–2 small, triangular teeth. Posteroventral carina with 5–7 small, pointed teeth. Anterodorsal carina of protibiae moderately raised and protruded into two ± well developed broad, triangular lobes in basal half and a smaller lobe-like tooth in apical half of tibia. Posterodorsal carina with a small apical spine, otherwise unarmed. Dorsal carinae of meso- and metafemora unarmed except for 2– 3 rather small teeth on anterior carina (Fig. 335); occasionally with a single more prominent, triangular tooth one third the way along posterior carina (Fig. 334). Medioventral carina smooth except for a single, minute subapical spine. Ventral carinae very sparsely and minutely dentate, the two basal teeth occasionally more prominent than the remaining (Fig. 334). Ventral carinae of meso- and metatibiae minutely dentate, the posteroventral carina sometimes with an enlarged, triangular tooth about 1/3 off the base of tibia. Usually with a very large, roundly triangular prae-medial lobe on posterodorsal carina and a distinct triangular tooth on anterodorsal carina (Fig. 334), but sometimes only represented by slightly enlarged teeth (Fig. 335). Posterodorsal carina forming a rounded, dentate lobe at the apex of tibia. Probasitarsus with a uniformly raised dorsal carina, as long as remaining segments combined. Second tarsomere ¼ the length of basitarsus with the dorsal carina raised and rounded. Meso- and metabasitarsus as long as remaining tarsomeres combined except claw and with an apically dentate dorsal carina, which gradually increases in height towards the apex.

♂♂ (Fig. 77): Medium-sized (body length 113.5–124.5 mm) and rather slender for the genus with long alae (46.0–59.0 mm). General colouration of body and legs ochracheous to greyish mid brown often with a slight green or yellow wash on mesonotum. Head with a ± distinct pale yellowish spot between the eyes, three distinct pale orange longitudinal lines on the vertex and a broad blackish postocular stripe along the cheeks. Tegmina greyish mid brown with the central portion darker brown and the anterior margin pale yellowish or white. Costal region of alae greyish bown with sepia veins, the anterior margin pale yellow or white in the basal portion. Anal region transparent grey with brown veins. Mid and hind legs with indistinct pale trans- verse bands. Bases of profemora pale orange. Leg armature dark brown. Eyes pale reddish brown. Dorsal surface of scapus dark brown to black, remaining antennomeres yellowish or greyish brown.

Head: Generally as in ♀♀ but eyes more prominent and projecting hemispherically; their length contained only a little more than 2x in that of cheeks. Antennae filiform and projecting over posterior margin of metanotum. Scapus almost 3x longer than wide and dorsoventrally compressed. Length of antennomeres increasing in length towards apex of antennae, all densely sethose.

Thorax: Pronotum generally as in ♀♀, distinctly shorter and narrower than head. Mesothorax 2.5x to almost 3x longer than head and pronotum combined. Meso- and metasternum with a very fine longitudinal median carina. Tegmina projecting over posterior margin of metanotum, elongate, narrowed towards the base and with a rounded central hump. Alae ± distinctly projecting over posterior margin of abdominal tergite IV.

Abdomen: Median segment 2x longer than metanotum. Segments II–V roughly of equal length and width, about 5.5x longer than wide and shorter than median segment; all gently constricted medially. VI slightly shorter than previous and about 5x longer than wide. VII slightly shorter than IV, about 4x longer than wide and slightly broadened posteriorly. Tergite V with minute posteromedian tubercle. VIII 2/3 the length VII strongly broadening towards posterior margin and convex. IX a little longer than VIII, but distinctly narrower and constricted medially. Anal segment about as long as IX, laterally compressed and tectiform. Semi-tergites very elongate, strongly tapered, slender with a narrow apex and gently down-curving (Fig. 248); lateral surface with a conspicuous longitudinal impression in apical portion. Interior surface with a longitudinal median bulge apically which is densely covered with minute black teeth. Cerci elongate, in-curving and tapered towards the apex. Poculum reaching about 2/3 the way along tergite VIII, strongly convex, cup-like and with a very prominent and acute central hump.

Legs: All very long and slender, profemora longer and mesofemora almost as long as head, pro- and mesothorax combined, metafemora reaching about half way along abdominal segment V and metatibiae slightly exceeding apex of abdomen. Armature generally as in ♀♀ but slightly less prominent and lacking any considerably enlarged teeth or lobes. Dorsal carinae of meso- and metafemora smooth except for a very few minute teeth, two outer ventral carinae minutely serrate. Meso- and metatibiae occasionally with a single enlarged, triangular pre-medial tooth on posterodorsal carina. Basitarsi as in ♀♀, but dorsal carina not considerably raised.

Variation: While ♂♂ are quite constant, ♀♀ show a great range of intraspecific variability concerning to the size (→ Table 16) and armature of the legs. A ♀ contained in Brunner v. Wattenwyl’s collection in NHMW (collection No. 17.228) is remarkable for its very large size (body length 236.0 mm) and poorly developed leg armature (Fig. 335). An even less developed leg armature is seen in the HT of Pharnacia spectabilis Redtenbacher , which is considerably shorter (208.5 mm) but was possibly collected from the same locality (see comments below). The ♀♀ in SMFM measure body lengths of only 185.0– 197.5 mm and are a little more robust, which might be due to they were collected from a different locality possibly at higher altitude in the central highland of Sri Lanka. These ♀♀ furthermore have the leg armature much more strongly developed, bearing prominent teeth on the meso- and metafemora and a large, roundly triangular pre-medial dorsal lobe on the meso- and metatibiae (Fig. 334). These are just represented by small triangular teeth in the two ♀♀ in NHMW .

Eggs (Figs. 177–178): The following description is based on a single fully developed egg extracted from the ovipositor of the ♀ from Racuapura in BMNH (accession No. BM 1922-468) .

Capsule basically lens-shaped, laterally compressed, longer than high. General colouration of capsule and operculum dark yellowish brown, keel, capitulum and micropylar plate darker. Whole capsule surface minutely punctured and wrinkled, being covered with irregular raised carinae and tubercles. A dorsoventral keel begins and ends at the operculum and is only interrupted at the micropylar plate and notched at polararea. Lateral surfaces of keel with fine impressed radial ridges. Micropylar plate bilobed, forming an oval lobe on each side of the dorsal median line and surrounded by a bold black band. Central region of plate roughly granulose. Micropylar cup small, at polar end of plate and near centre of dorsal surface. Operculum slightly convex, oval and with an irregularly shaped capitulum on a short stalk in the centre.

Measurements [mm]: length (including capitulum) 5.5, length 4.9, width 2.9, height 3.8, length of micropylar plate 1.3.

Comments: Westwood (1859: 75) originally described Phibalosoma hypharpax based on a single ♂ from “ Ceylon ” in the BMNH and provided a very accurate illustration of the HT including details of the genitalia ( Westwood, 1859: pl. 13: 6, 6a–b). Kaup (1871b: 37) provided a description of the so far unknown ♀ and a description and illustration of the egg (1871a: 19, pl. 1: 11). The ♀ recorded by Kaup (1871b) is present in Kaup’s collection in HLDH, but the appertaining egg is not traced.

Examination of the ♀ HT of Pharnacia spectabilis Redtenbacher, 1908 in NHMW and comparison with various ♀♀ of Ph. hypharpax (Westwood) have proven Redtenbacher’s species to be a synonym (syn. nov.). The specimen is however remarkable for its poorly developed leg armature and lack of any conspicuously enlarged teeth or lobes on the mid and hind legs, thus representing an extreme and showing the wide range of intraspecific variability in this species. Redtenbacher (1908: 453) recorded a body length of 200 mm for the HT but the exact length is 208.5 mm. Furthermore, the specimen was obviously collected along with one ♂ and the giant 236.0 mm ♀ of Ph. hypharpax in NHMW, as it bears exactly the same data and labels stating “ Ceylon, Dr. Haly”.

Ph. hypharpax (Westwood) appears to be quite widely distributed in the tropical lowland and mountainous regions of southern Sri Lanka but absent in the northern portion of the island. Although this species is represented in several European museum collections almost all specimens lack a more precise locality than “Ceylon”. Only one specimen has so far been recorded from SE-India. ♀♀ in particular show a considerable range of intraspecific variation, concerning to the size, colouration and armature of the legs (see above) .

Distribution (Fig. 381): Sri Lanka (Racuapura; Kandy & Karen Hill) and Southeast India (Mercara).

Number of specimens examined: 24

115. Phobaeticus kirbyi Brunner v. Wattenwyl, 1907, ♂ NE-Sarawak, Batu Niah (coll. FH, No. 0160-8) 116. Phobaeticus chani Bragg spec. nov., ♀ HT, Sabah, Penampang District, Ulu Moyog (BMNH)

117. Phobaeticus chani Bragg spec. nov., ♂ PT, Sabah, Sipitang (BMNH)

118. Phobaeticus rex ( Günther, 1928) , ♀ HT, Sumatra, Redjang-Lebong ( MNHU)

119. Phobaeticus philippinicus (Hennemann & Conle, 1997) , ♀ Philippines, Mindoro Island (coll. OC)