Macrophasma, Hennemann, Frank H. & Conle, Oskar V., 2006

Hennemann, Frank H. & Conle, Oskar V., 2006, Stephanacridini Günther, 1953, with the descriptions of a new genus and three new species of Stephanacris Redtenbacher, 1908 (Phasmatodea: “ Anareolatae ”), Zootaxa 1283, pp. 1-24 : 3-5

Macrophasma n. gen.

Figs. 12–15 , 22

Type species: Hermarchus biroi Redtenbacher, 1908: 445 , by present designation.

Hermarchus, Redtenbacher, 1908: 444 . (in part) Günther, 1929: 625 –626 & 686–690. Herwaarden, 1998: 88. (in part) Zompro, 1997: 1 & 2, fig. 1.

Zompro, 2002: 182.

Otte & Brock, 2005: 154. (in part)

Etymology

The generic name refers to the remarkably large size of these insects (gr. = large), with certain species representing some of the world’s largest and heaviest insects.

Diagnosis

Male, Female. Large to very large Stephanacridini (body lengths: ΨΨ incl. subgenital plate> 17 cm, ɗɗ> 12 cm), body surface unarmed and glabrous. ΨΨ rather massive insects, body dorsoventrally flattened, oval in cross­section and ± expanded laterally. ɗɗ elongate, slender and cylindrical. ΨΨ apterous, ɗɗ with scale­like tegmina and well developed alae, projecting over abdominal tergite IV. Ocelli absent. Head strongly globose to almost spherical, indistinctly longer than wide. Vertex strongly convex, unarmed. Eyes circular and projecting hemispherically. Antennae long and filiform, projecting over posterior margin of metanotum in ΨΨ and over median segment in ɗɗ. Scapus oval in cross­section, longer than wide. Pedicellus cylindrical, distinctly shorter than scapus. Following antennomeres first increasing, then decreasing in length towards apex of antennae. Pronotum distinctly narrower than head. Mesothorax elongate and parallel­sided in ɗɗ, distinctly narrowed at the anterior and posteriorly broadened in ΨΨ. Mesopleurae of ΨΨ prominently laterally expanded, forming a longitudinal, dorsoventrally flattened ± rounded lobe; in one case this is armed with a longitudinal row of dorsoventrally compressed, triangular teeth. Meso­ and metasternum smooth. Median segment about as long as (ΨΨ) or distinctly longer than metanotum (ɗɗ). Abdomen of ɗɗ very slender and cylindrical, tergites II–VII distinctly longer than wide, VIII–X broader than previous ones. Tergites II–VII of ΨΨ slightly transverse to 1.5x longer than wide. Lateral margins expanded, either of uniform width, or each distinctly rounded. Tergites VIII–X considerably narrower than previous ones, not expanded laterally. Sternites smooth. ΨΨ without a praeopercular organ. Anal segment of ΨΨ with posterior margin rounded or truncate, of ɗɗ with a posteromedian notch. Supraanal plate of ΨΨ prominent, roughly semi­circular and distinctly projecting over posterior margin of anal segment. Vomer developed as a well sclerotized, roughly triangular plate. Cerci of both sexes very small, oval in cross­section and tapered towards a pointed tip. Gonapophyses of ΨΨ elongate and filiform, projecting considerably over anal segment and almost reaching apex of subgenital plate. Subgenital plate of ɗɗ indistinct, slightly convex and scoop­like. Subgenital plate of ΨΨ elongate and distinctly projecting over apex of abdomen, tapered towards the tip. Legs all long and slender, profemora about as long as pro­ and mesonotum combined, hind legs not projecting over apex of abdomen. Profemora compressed and curved basally. Femora and tibiae trapezoidal in cross­section, the dorsal carinae close to each other. Carinae more or less prominently dentate. Medioventral carina of femora faint, unarmed or at best with a few minute spines. Basitarsi simple with all carinae minutely dentate, longer than the two following tarsomeres combined.

Eggs

Large and globose with capsule slightly longer than wide and circular in cross­section. Capsule surface minutely punctuated and velvet­like, densely covered with very short setae. Micropylar plate about half the length of capsule, strongly dilated medially. Internal micropylar plate closed. Operculum circular, slightly convex. Capitulum cone­shaped with deep, rounded lateral impressions. Capitular stalk very short.

Differentiation

Closely related to Hermarchus Stål, 1875 but easily distinguished by: the glabrous body surface, distinctly globose or almost spherical head, circular eyes (in Hermarchus slightly truncate and with a black outer margin anteriorly) and unarmed mesonotum of both sexes, as well as the prominently dilated, ledge­like and occasionally dentate mesopleurae of ΨΨ. The eggs differ from those of Hermarchus by being comparatively larger and more globose, almost smooth and velvet­like capsule­surface, shorter micropylar plate and prominent lateral impressions of the capitulum. Furthermore, Hermarchus is restricted to Melanesia ( Fiji, Tonga, Samoa, Vanuatu, New Caledonia, New Hebrides & western French Polynesia) and hence geographically isolated from Macrophasma n. gen. (Hennemann & Conle, in progress).

Comments

Examination of the species included in Hermarchus Stål, 1875 (type­species: Phibalosoma pythonius Westwood, 1859: 73 , by subsequent designation of Kirby, 1904: 360) by Redtenbacher (1908: 444) and subsequent authors has shown the genus to be polyphyletic. All New Guinean species so far described in Hermarchus Stål differ considerably from the Melanesian taxa included in the genus, which are congeneric to the type­species H. pythonius (Westwood) from Fiji. Therefore, Macrophasma n. gen. is established to include the five New Guinean taxa described in Hermarchus Stål.

A revision of Macrophasma n. gen. at the species level will provide detailed descriptions of all known species (Hennemann & Conle, in progress).

Distribution

New Guinea (believed to be endemic).

Species included

1. Hermarchus biroi Redtenbacher, 1908: 445 .

= Hermarchus annulatus Günther, 1929: 689 . syn. nov. = Hermarchus mülleri Redtenbacher, 1908: 446 . syn. nov.

2. Hermarchus lyratus Redtenbacher, 1908: 447 . 3. Hermarchus oreïtrephes Günther, 1929: 687 , pl. 6 (Ψ).

Figures

FIGURES 12 – 16. 12. Macrophasma n. gen. biroi (Redtenbacher, 1908), Ψ (coll. FH). 13. Macrophasma n. gen. biroi (Redtenbacher, 1908), PLT ♂ (ZMUH). 14. Macrophasma n. gen. oreithrephes (Günther, 1929), Ψ (coll. FH). 15. Macrophasma n. gen. lyrata (Redtenbacher, 1908), Ψ (RMNH). 16. Stephanacris laeviceps n. sp., HT Ψ (RMNH).

FIGURES 17 – 22. 17. Stephanacris draconius n. sp., HT Ψ (ZSMC). 18. Stephanacris multilobatus n. sp., PT Ψ (Coll. FH). 19 – 22. Eggs [scale = 1 mm]. 19. Stephanacris draconius n. sp. PT, dorsolateral view (ZSMC). 20. Stephanacris multilobatus n. sp. PT, dorsolateral view (coll. FH). 21. Stephanacris laeviceps n. sp. PT, dorsolateral view (RMNH). 22. Macrophasma n. gen. biroi (Redtenbacher, 1908), dorsolateral view (coll. FH).