Tisamenus ranarius (Westwood, 1859)

Hennemann, Frank H., 2025, A taxonomic review of Philippine Obrimini stick insects: The genus Tisamenus Stål, 1875 (Insecta: Phasmatodea: Heteropterygidae: Obriminae), Faunitaxys 13 (24), pp. 1-85 : 68

Tisamenus ranarius (Westwood, 1859)

( Fig. 38)

Acanthoderus ranarius Westwood, 1859: 53 , pl. 4: 3 (♀).

HT, ♀: Phil. Isl.,54 76; Acanthoderus ranarius Westw. Philippine Isl. ; ranarius ; Holotype; BMNH(E) #845221 [NHMUK].

Tisamenus ranarius, Kirby, 1904: 399 .

- Zompro, 2004: 207.

- Otte & Brock, 2005: 335.

- Brock et al., 2016: 191. (Type data)

- Brock & Büscher, 2022: 521.

- Hennemann, 2023b: 128.

Heterocopus ranarius, Redtenbacher, 1906: 42 .

- Bruner, 1915: 229.

Ilocano ranarius, Rehn & Rehn, 1939: 463 .

Material examined

1 ♀: Manilla; Acanthoderus Ranarius W. pl. 4: 3 [ UMO, No. 495] ;

1 ♀: Filipinas, Mazarredo ; Heterocopus ranarius West.[ MNMS] ;

1 ♀: Philippinen, Luzon Island,Prov. Laguna, SantaRosa , localcollectorVII. 2004 [coll. FH, No. 1551-1] .

Differentiation. – Females ( Fig. 38) of this small but distinctive species (the only sex known) are morphologically very close to those of T. trapezoides n. sp. with which they share the dentiform apical protrusion on the exterior lateral carina of the scapus ( Fig. 38 I-J), remarkably reduced and almost indiscernible triangular mesonotal area ( Fig. 38J) and sub-spiniform postero-laterals of the abdominal terga. All three characters distinguish both species from all other congenerics and are likely to represent autapomorphies of two sister taxa. These ♀ are however easily distinguishable from those of trapezoides by the comparatively less widening meso- and metathorax, just weakly and obtusely granular lateral margins of the meso- and metapleurae (tubercular in trapezoides ), smaller and merely obtusely tubercular metapleural (sub-spinose in trapezoides ), much smaller and obtusely rounded sub-orbitals ( Fig. 38J), less definite triangular area of the pronotum,notably shallower and broader medio-longitudinal bulge of the dorsal body surface, notably more defined longitudinal carinae of the mesosternum ( Fig. 38I), considerably less developed armature of the limbs (metafemora in particular) and having the tibiae coloured like the corresponding femora (contrastive ochre to clay coloured in trapezoides ).

Variability. – Body length of ♀ 42.0- 42.2 mm.

Remarks. – Westwood (1859:53) originallydescribed Acanthoderus ranarius from a unique ♀ from an unspecified locality in the collection of NHMUK ( Fig.38E).Although there is a further ♀ inthe collection of UMO, which is most likely to have been examined by Westwood, this is not regarded as a paratype because Westwood did not mention any specimens other than the ♀ inNHMUK.Luckily,the UMO specimenbears a labelthat states “ Manilla ” and thereby proves ranarius to be fromthe islandof Luzon.The specimen in the author’s collection serves another definite record of ranarius from Luzon, but the ♂ as yet remains unknown. The holotype in NHMUK bears an egg in its ovipositor, which however could not be extracted for the present study ( Fig.38F).The generic position of this species has been interpreted differently in the past, which was perhaps due to the tiny triangular mesonotal area, that is almost undiscernible and distinguished this species from all other congenerics. Redtenbacher (1906: 42) allocated it to the genus Heterocopus Redtenbacher, 1906 and Rehn & Rehn (1939: 463) affiliated it to Ilocano Rehn & Rehn, 1939 , which however was shown to be a synonym of Tisamenus ( Bank et al., 2021) . The apparent close affinity to T. deplanatus ( Westwood, 1848) and T.cervicornis Bolívar, 1890 leaves no doubt that ranarius is a member of Tisamenus .

Distribution. – Philippines [NHMUK – type locality; MNMS]). Luzon: Province Quezon (Manila [OUM]); Province Laguna (Santa Rosa [FH]).