Two new species of Megacrania Kaup in Indonesia are described and compared with other related species. There are now three confirmed species in Indonesia.
Introduction
The current status of the species in the genus Megacrania Kaup, 1871 is somewhat problematical. Hsiung (1991) recognized six species distributed along the western Pacific Ocean from the northeast of Australia to New Guinea, the Solomon Islands, Indonesia, the Philippines, extending to Micronesia and the southern coast of Taiwan. Subsequently, Hsiung & Yang (2000) concluded that the single Megacrania species of Australia was in fact Megacrania batesii, though its average size was slightly smaller than the type specimen of M. batesii.
The distribution of species in Indonesia is not clear. Willemse (1955) first described a species of Megacrania from Indonesia as wegneri. He gave a detailed morphological description with measurements based on both male and female specimens collected in Obi Is., Moluccas. He also concluded that his new species was related to Megacrania alpheus Westwood, 1859.
I have examined Willemse's paratypes and found that they match his description. Willemse further remarked that M. alpheus also occurs on Obi, but only along the coast (Kasowari, Wajaloar), whereas M. wegneri occurs in the interior of the island. He also listed a number of localities for M. alpheus including Key Is. (Dulan).
This study seeks to resolve the following questions: how close is M. wegneri to M. alpheus? Does M. alpheus actually occur on Obi Is., considering that Willemse did not provide any comparative data? How many species of Megacrania are there in the Indonesian fauna?
Comparison of Megacrania wegneri (paratype) with related species.—
I have compared Willemse's female paratype (Obi Is.) with the female lectotype of M. alpheus (Ceylon; mislabelled, see Hsiung, 1991 and Table 1) and found that M. alpheus was no closer to M. wegneri than to other species in this genus.
Hsiung & Yang (2000) compared M. wegneri with the Australian species M. batesii Kirby, 1896. They found that although the two species had some similarities, the major difference was in the length of the wing, which reached to the posterior margin of the 4th abdominal tergum in M. wegneri and the posterior margin of the 2nd abdominal tergum in M. batesii. The other difference was in the lateral margins of the mesonotum of M. batesii which are less spiny, the first two teeth being larger and sharper, whereas in M. wegneri, the lateral margins are strongly spiny with the first two teeth not particularly strong.
I also compared M. wegneri with Megacrania tsudai Shiraki, 1933 from Taiwan. The major differences are in the length of the wing and the granules of the mesonotum (Table 2).
Megacrania brocki Hsiung, new species
Megacrania alpheus [nec (Westwood, 1859)]: Willemse, 1955. Treubia, 23: 45 [taxonomy, remarks on M. alpheus (Westwood)].
Holotype.— Female (Fig.1)
Head: oval, slightly porrect, a little longer than broad.
Thorax: pronotal disc slightly shorter than broad, slightly narrowed at anterolateral angles; dorsal surface uneven with strongly defined margins; mesonotum about 2.2 × length of pronotum, surface with numerous elongate and sharp granules quite evenly distributed over anterior three quarters of its length; with two nearly parallel rows of strong triangular spines near the lateral margins, which gradually turn inward posteriorly but without meeting; a median sulcus or keel distinctly present.
Wing: tegmina elongate-ovate, equal in length to mesonotum. Hind wings slightly shorter than other species, 1.8 × as long as the tegmina; reaching 2/3 of the 3rd tergum.
Legs: anterior femora about 1.5 × as long as the mesonotum, with ridge bearing a few spines visible in ventral view, 10 spines on right, 12 on left; tibiae of all legs without spines; first tarsal article of front leg as long as the following three articles together; the first three articles of middle and hind legs of equal length, fourth smaller, fifth elongate, its apex expanded.
Abdomen: elongate; about 3.6 × as long as mesonotum; segments I–VI wider than the remaining ones; posterior margin of anal segment nearly round, a distinct split at its center; cerci broad, lamellate, apices rounded; subgenital plate 19.5 mm, slightly longer than mesonotum, its margins gradually narrowing apically, not attaining extremities of the cerci, center of ventral surface with longitudinal ridge.
Coloration.— General color pale green.
Measurements.— (Holotype) lengths (mm). Body 111.5; pronotum 8; mesonotum 18; tegmen 18; hindwing 33; front femur 27; median femur 16; hind femur 18.5; front tibia 24; median tibia 14.5; hind tibia 15.5.
Type material.— Holotype ♀, Key-Inseln, 1912, P. Kibler leg. 81 ♀♀ paratypes, bearing the same labels as the holotype. 2 ♀♀ (1 nymph), Isl. Obi, Kasowari - Lodii (nymph without Lodii), one collected 19-8, 1953, the nymph collected 20-8, 1958 (both with C. Willemse's identification label as Megacrania alpheus). The holotype and paratypes are deposited in the Staatliches Museum für Naturkunde Stuttgart, Germany.
The paratypes agree with the description of the holotype. Four specimens have very similar morphological characters to the holotype, but their localities are not clear. Therefore they were not listed as paratypes (three specimens collected in Bongu, one in Pelew Ins.). The one collected in Pelew Ins. might be from Palau Ins. However, it needs further proof and study.
Measurements.— (Paratypes). Lengths (mm). Body 104.5 – 128.5; pronotum 8–9; mesonotum 17–20; tegmen 16.5–21; hindwing, 30–36.5; front femur 25–29; median femur 15–17; hind femur 15.5–19; front tibia 22–27.5; median tibia 12.5–15; hind tibia 15–17.5.
Distribution.— Known only from S. Moluccas.
Etymology.— This new species is named after Paul Brock for his help in this project and his contributions to phasmatid study.
This new species has been compared with M. wegneri, M. alpheus, M. batesii, and M. tsudai. Their differences are listed in tables 3–7.
Megacrania rentzi Hsiung, new species
Holotype.— Female (Fig. 2)
Head: oval, slightly porrect, longer than broad.
Thorax: pronotal disc as long as wide; mesonotal lobes much longer than broad, about 2.5 × the length of pronotum, its surface with about 60 elongate granules evenly distributed on the anterior 80% of surface, some granules connected to each other in the central region; the lateral margin of mesonotum not spiny with very dull teeth.
Wing: tegmina elongate ovate, slightly longer than mesonotum; hind wings of moderate size, about 2 × as long as the tegmina, surpassing the posterior margin of the 2nd abdominal tergum.
Legs: anterior femora 1.7 × the length of mesonotum; the femora with a few spines visible in ventral view. 11 spines on left femora and 9 on the right; the middle femora each with 3 spines; the hind femora with 4 spines on left and 7 on the right. Tibiae of all legs without spines; first tarsal article of front leg as long as the following three articles together; the first three tarsal articles of middle and hind legs of equal length, the fourth smaller and the fifth elongate with apex expanded.
Abdomen: elongate, about 3.5 × as long as mesonotum; segment II–IV slightly wider than remainder which are gradually narrowed towards abdomen extremity. Posterior margin of anal segment nearly square. Cerci long, surpassing apex of operculum; subgenital plate not attaining extremities of cerci.
Coloration.— General color light brown, head and thorax darker.
Measurement (mm).— Length of body 132; median length of pronotum 11.5; median length of mesonotum 21; length of tegmen, 24; length of hind wing 40; length of femora: front 34.5, middle 21 and hind 26; length of tibiae: front 31, middle 20 and hind 23.
Allotype.— Male (Fig. 3). Agrees generally with holotype, but smaller and differing as follows: about 70 granules on surface of mesonotum, lateral margin of mesonotum more spiny; hind wings reach to middle of the 4th abdominal segment; coloration testaceous; all femora with a few spines visible in ventral view; fore with 3 spines on left and 2 on right; the middle with 3 on right and none on left (leg regenerated); the hind with 4 on either side.
Measurement (mm).— Length of body 80.5; median length of pronotum 6; median length of mesonotum; 12.5 length of tegmen 15; length of hind wing 40; length of femur: front 24, middle 13, hind 16; length of tibiae: front 20.5, middle 11.5, hind 14.5.
Type material.— Holotype ♀, bearing three labels:
1. Tandjjong. S.D. Borneo, Fr. Suck leg. Ded 31. XII. 1895; 2. Z.M.H. Hamburg; 3. M. alpheus. Allotype ♂, bearing three labels: 1. Borneo; 2. Staat Museum für Tierkunde Dresden; 3. alpheus. The holotype is deposited in the Universität Hamburg, Zoologisches Institut und Zoologisches Museum and the allotype is in the Staatliches Museum für Tierkunde.
Distribution.— Known only from Borneo.
Etymology.— This species is named after David Rentz in recognition of his support and encouragement in the present research.
This new species is compared with other related species (Table 7 – 12).
Acknowledgments
I thank Andreas Stelzer for preparing the photographs. I am also very grateful to V.R. Vickery, Emeritus Curator, Lyman Entomological Museum and Research Laboratory, McGill University and R. Manuel for a critical review of the manuscript. Thanks are also due to Mrs. J. Marshall (Natural History Museum, Entomology, London, U.K) for the loan of type material, to D. Rentz (CSIRO, Entomology, Canberra, Australia) and P. Brock (“Papillon” Slough, U.K.) for providing references and specimens.
Literature Cited
Table 1.
Morphological differences between M. wegneri (paratype female) and M. alpheus (lectotype female).
Table 2.
Morphological differences between M. wegneri (paratype female) and M. tsudai (paratype female).
Table 3.
Morphological differences between M. wegneri (paratype female) and M. brocki (holotype female).
Table 4.
Major morphological differences between M. brocki (holotype female) and M. alpheus (lectotype female).
Table 5.
Major morphological differences between M. brocki (Key-Inseln) and lectotype of M. batesi.
Table 6.
Morphological differences between M. brocki and M. batesii (specimen from Bismarck Is., New Pammer)
Table 7.
Morphological differences between M. brocki and M. tsudai (Taiwan).
Table 8.
Morphological differences between M. rentzi (holotype female) and M. wegneri (paratype female).
Table 9.
Morphological differences between M. rentzi (holotype female) and M. tsudai (paratype female).
Table 10.
Morphological differences between M. rentzi (holotype female) and M. brocki (holotype female).
Table 11.
Morphological differences between M. rentzi (holotype female) and M. batesi (lectotype female).
Table 12.
Morphological differences between M. rentzi (holotype female) and M. alpheus (lectotype female).
