Otraleus Günther, 1935

Bresseel, Joachim & Constant, Jérôme, 2017, Philippine mossy forest stick insects: first record of the genus Otraleus Günther, 1935 in the country, with four new species, and the new genus Capuyanus gen. nov. (Phasmida, Diapheromeridae, Necrosciinae), European Journal of Taxonomy 265, pp. 1-31 : 2-5

Genus Otraleus Günther, 1935

Otraleus Günther, 1935: 28 (description), pl. 2, fig. 18 (illustration).

Otraleus – Bradley & Galil 1977: 182 (list). — Hennemann 1998: 122 (type data). — Bragg 2001: 639 (type data). — Zompro 2004: 316 (type data); 2005: 267 (type data). — Otte & Brock 2005: 242 (type data). — Seow-Choen 2016: 199 (description, notes on holotype).

Type species

Otraleus hypsimelathrus Günther, 1935 , by original designation.

Diagnosis

Small and cryptically shaped Necrosciinae , body surface brown to green, apterous to brachypterous. Head longer than wide, antennae long and filiform, strongly projecting over apex of abdomen. Most species have well developed posterolateral lobes on several abdominal segments. Subgenital plate in females laterally compressed, not reaching apex of abdomen. Legs smooth and unarmed, claws small. Cerci of males surpassing apex of abdomen.

The genus Otraleus Günther, 1935 can be distinguished from other genera in Necrosciinae by the combination of the following characters:

1. Legs long in relation to body length, all carinae developed and unarmed.

2. Abdominal segments with lobes or extensions postero-laterally on at least terga III–VII in females. 3. Body length not exceeding 50 mm in males and 55 mm in females.

4. Subgenital plate in females not surpassing anal segment and laterally flattened at the base.

5. Anal segment notched posteriorly and rounded postero-laterally.

6. Praeopercular organ absent in females.

7. Vomer well developed, elongated, flattened and strongly tapered.

The exact systematic position and the most closely related genera are still unknown. The Necrosciinae of the Philippines and Sulawesi are poorly studied and more material is needed to resolve its systematic position.

Species included and distribution

Otraleus applai sp. nov. ( Philippines: Luzon: Mountain Province and Benguet Province)

Otraleus bellemansae sp. nov. ( Philippines: Luzon: Mountain Province)

Otraleus christianae sp. nov. ( Philippines: Luzon: Mountain Province and Ifugao Province)

Otraleus elizabethae sp. nov. ( Philippines: Luzon: Benguet Province)

Otraleus hypsimelathrus Günther, 1935 ( Indonesia: Sulawesi: Mt Latimodjong)

Otraleus labanrataensis Seow-Choen, 2016 ( Malaysia: Sabah: Mt Kinabalu)

Note on Otraleus hypsimelathrus Günther, 1935

Otraleus hypsimelathrus Günther, 1935: 28 (description), pl. 2, fig. 18 (dorsal aspect of habitus).

Otraleus hypsimelathrus – Günther 1938: 59 (list). — Hennemann 1998: 122 (list). — Zompro 2005: 267 (type data). — Otte & Brock 2005: 242 (type data). — Seow-Choen 2016: 199 (notes on holotype).

To supplement Günther’s (1935) original description, we provide illustrations of the holotype along with a distribution map for the species which is so far known from a single location in Sulawesi ( Fig. 1 ). Currently only the male is known.

Males of O. hypsimelathrus Günther, 1935 can be separated from the four newly described Philippine species of Otraleus by the following combination of characters:

1. Abdominal terga II–VIII with definite lobes postero-laterally.

2. Ventral portion of thorax black.

3. Apterous.

4. Mesonotum, median segment and abdominal terga at best with an indefinite hump posteromedially.

Key to the Philippine species of Otraleus and Capuyanus gen. nov.

1. Abdominal terga without postero-lateral lobes; females with subgenital plate strongly tapered, projecting over apex of tergum X; males with swollen and conical thornpads on anal segment (genus Capuyanus ) ............................................................................. Capuyanus magwilangi sp. nov.

– Abdominal terga with postero-lateral lobes; females with subgenital plate not strongly tapered, not projecting over apex of tergum X; males without swollen and conical thornpads on lower posterior margin of anal segment (genus Otraleus )....................2

2. Elytra and alae present ...................................................................... Otraleus christianae sp. nov.

– Elytra and alae absent...........................................................................................................3

3. Abdominal terga armed with spines or tubercles posteromedially..................................4

– Abdominal terga smooth ......................................................................... Otraleus applai sp. nov.

4. Vertex elongated and slightly conical; meso- and metanotum with a definite, vertical, elongated blunt spine posteromedially ............................................ Otraleus bellemansae sp. nov.

– Vertex not conical; meso- and metanotum at best with a short conical spine posteromedially ... ...................................................................................................... Otraleus elizabethae sp. nov.

Distribution

Currently known from Sulawesi ( Indonesia), Borneo ( Malaysia: Sabah) and Luzon Island ( Philippines).

Figures

Fig. 1. Otraleus hypsimelathrus Günther, 1935, ♂, holotype (ZMHB). A. Habitus, lateral view. B. Apex of abdomen, lateral view. C. Distribution map in Sulawesi. (Photographs © O. Conle and F. Hennemann.)