Tisamenus cervicornis Bolívar, 1890

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 : 15-20

Tisamenus cervicornis Bolívar, 1890

( Fig. 6-8, 46 C-D)

Tisamenus cervicornis Bolívar, 1890: 307 , pl. 19: 5, 5a (♀).

LT, ♀ (by present designation): Camarines, Mazarr; Tisamenuscervicornis Bolivar; Sintipo; MNCN, Cat.Tipos N ° 1596; [ MNMS] ;

PLT, ♂: Camarines, Mazarr.; Tisamenus cervicornis Bolivar ; Sintipo; MNCN, Cat. Tipos N° 1597; Tisamenus cervicornis ♂ Bolivar 1890 , LECTOTOYUS, O. Zompro VII.2001 [MNMS].

- Kirby, 1904: 399.

- Redtenbacher, 1906: 44.

- Bruner, 1915: 229.

- Paris, 1994: 169.

- Zompro, 2004: 206.

- Otte & Brock, 2005: 334.

- Brock & Büscher, 2022: 521.

- Hennemann, 2023b: 128.

Hoploclonia cervicornis, Rehn & Rehn, 1939: 478 . (Deplanata Group)

Hoploclonia deplanata, Rehn & Rehn, 1939: 477 , pl. 35: 34 (♀). (Deplanata Group) (Misidentification)

Tisamenusdeplanata, Dräger, 2012: 14, fig. 23-25. (Misidentification)

= Hoploclonia fratercula Rehn & Rehn, 1939: 481 , pl. 31: 5 (♂).

HT, ♂: Butucan , Tayabas , Luzon, Philippines (W. Boettcher); X. 4.1916; Hoploclonia fratercula Rehn + Rehn, Type, H.1253; Data Base Serial No. Assigned as Type No. September 2008. Type # 9126 [ ANSP]. n. syn .

- Otte, 1978: 79. (Type data)

Tisamenus fratercula, Zompro, 2004: 206

- Otte & Brock, 2005: 335.

- Brock & Büscher, 2022: 521.

- Hennemann, 2023b: 128.

Material examined

2 ♀, 1 ♂, 2 eggs: Coll. R.I.Sc.N.B., Philippines, Pocdol Mts , Ex breeding 2015 Rob Krijns [ RBINS] ;

2 ♂: Coll. R.I.Sc.N.B., Philippines, Luzon, Bicol, Pocdol Mts , ex breeding 2014 F4, B. Kneubühler [ RBINS] ;

1 ♀, 1 egg: Philippinen, S Luzon Island, Provinz Quezon, Tayabas, Mount Banahao , local collector II.2010 [ FH, No. 0905-8 & E2] ;

1 ♀: Philippinen, S Luzon Id., Bicol Region, Provinz Sorsogon, Pocdol Mountains , local collector XI.2011 [ FH, No. 0905-9] ;

3 ♀, 1 ♂: Ex Zucht F. Hennemann 2017, Herkunft: Philippinen, Luzon, Bicol Reg., Pocdol Mts. , Mount Pulog X.2009 [ FH, No.’s 0905-1 to 4] ;

2 ♀, 2 ♂, 2 eggs: Philippinen, S-Luzon, BicolRegion, Provinz Albay, Mount Mayon , Tabaco , local collector II.2011 [ FH, No’s 0905-5 to 7, 18, E1] ;

3 ♀, 5 ♂, 1 ♀ (penultimate instar): Philippinen, SO Luzon Id., Caramoan Peninsula, Prov. Camarines Sur, Lagonoy, local collector II.2012 [ FH, No’s 0905-13 to 16, 19 to 22] ;

1 ♀, 2 ♂: Philippinen, S Luzon Id., Bicol Region, Provinz Sorsogon, Mount Bulusan , local collector II.2013 [ FH, No’s 0905-10 to 12] ;

1 ♀, 1 ♂: Philippinen, S-Luzon, Bicol Region, Provinz Albay, Tiwi , local collector I.2011 [ FH, No’s 0905-23 & 24] ;

A. ♀ LT dorsal view [ MNMS]. B . ♀ LT lateralview [ MNMS]. C . ♂ PLT dorsal view [ MNMS]. D . ♂ PLT lateralview[ MNMS]. E . ♂ dorsal view [ FH 1544-1 ]. F . ♂ dorsolateralview [ FH 1544-1 ]. G . ♂ lateral view [ FH 1544-1 ]. H . ♂ ventral view [ FH 1544-1 ]. I. Terminalia of ♂ in lateral view [ FH 1544-1 ]. J. Terminalia of ♂ indorsalview [ FH 1544-1 ]. K. Terminalia of ♂ inventralview [ FH1544-1 ]. L. Closeup of head and thorax of ♂ in dorsolateral view [ FH 1544-1 ]. M. Closeup of pro-, meso- and metasternum of ♂ [ FH, No. 1544-1] .

A. Dorsal view [FH 0905-9]. B. Dorsolateral view [FH 0905-9]. C. Lateral view [FH 0905-9]. D. Dorsal view [FH 0905-1]. E. Dorsolateral view [FH 0905-1]. F. Ventral view [FH 0905-1]. G. Terminalia in lateral view. H.Terminalia in dorsal view. I. Terminalia in ventral view. J. Closeup of head and thorax in dorsolateral view [FH 0905-1]. K. Closeup of pro-, meso- and metasternum [FH 0905-1].

A. Dorsal view [ FH 0905-4 ]. B. Dorsal view [ FH 0905-7 ]. C. Dorsolateral view [ FH 0905-7 ]. D. Lateral view [ FH 0905-7 ]. E. Ventral view [ FH 0905-7 ]. F. Anteroventralviewof lefthindleg. G. Terminalia of ♀ in dorsalview. H. Terminalia in ventralview. J. Closeup of head and thorax in dorsolateral view [ FH 0905-7 ] .

1 ♀, 1 ♀ (penultimate instar): Philippinen, Eastern Visayas, N-Samar Id., Prov. Northern Samar, Lope de Vega , local collector V.2012 [ FH, No’s 0905-25 & 26] ;

1 ♀, 1 egg: Coll. R.I.Sc.N.B., Philippines, EasternVisayas, Samar, Lope de Vega [ RBINS] .

Differentiation. – This species is morphologically closest to T. deplanatus ( Westwood, 1848) but slightly smaller on average and slightly stockier. Both sexes can easily be separated by the notably smaller mesonotal triangular area ( Fig. 6J, 7L), which covers less than half the length of the mesonotum and is not longer than it is wide across the anterolateral angles, particularly in ♀ however where it is an isosceles triangle and covers scarcely more than one-third of the mesonotal length. Males may also be distinguished from those of deplanatus by having the posteromedian portion of the meso- and metanotum flattened ( Fig. 7D; gibbous in deplanatus ) and the vomer with the hook arched towards the left ( Fig. 7H; backward-directed in deplanatus ) and ♀ can be distinguished by the rather flattened, just weakly longitudinally convex epiproct ( Fig. 6G; distinctly gibbous in deplanatus ). Moreover, the eggs ( Fig. 46C - D) are less bulgy than those of deplanatus and readily differ by having the capsule surface much more prominently sculptured and covered with a prominent raised network of fringy ridges, and the micropylar plate being noticeably shorter than the capsule with the anterior extension about equal in length to the two posterolateral extensions (much longer in deplanatus ). From the very similar T.armadillo Redtenbacher, 1906 both sexes of this species differ by the on average larger size, generally more pronounced head and body armature including spinose supra-orbitals on the head ( Fig. 6J; obtusely conical in armadillo ) and prominent and spinose and bifid anterior pronotals (compound and obtusely conical in armadillo ). The eggs clearly differ from those of armadillo by the slightly more elongate shape, distinct net-like sculpturing of the capsule, noticeably smaller micropylar plate and characteristic rim of fringes on the operculum. As stated for T. alviolanus Lit & Eusebio, 2010 above, distinction between these two species is very difficult and alviolanus is here not synonymised with cervicornis only because of its distribution and possible endemicity on the island of Negros and slight differences in the egg morphology as well as the more narrowed apex of the epiproct in ♀ if compared to cervicornis .

Egg ( Fig. 46 C-D). – Average size for the genus; capsule oval with the posterior one-third somewhat narrowed, slightly oval in cross-section and notably higher than wide with centraldorsal surface bulgy; capsule 1.4x longer than wide. Surface minutely granular and all over covered by a fairly dense but uneven raised network of fringy ridges; the lots between the ridges largest below anterior margin of capsule. The anterior margin somewhat inflated and covered by a broad rim of fringy structures. Micropylar plate fairly short and only about 0.7x the length capsule; basically Y-shaped with the median portion small, slightly narrowing towards the anterior end staying far below anterior margin of capsule, the two posterolateral extensions however large, extending on lateral surfaces of capsule almost at an angle of 90° and clearly surpassing longitudinal axis of egg.Outer margin marked by a distinctly raised fringy bulge and the inner portion raised and densely but unevenly covered with fringy structures. Posterior portion widely V-shaped with a distinct bowl-shaped micropylar cup in centre. Median line indistinct and very short. Operculum slightly oval; the outer margin with a rim of fairly long-fringe-like appendages and in centre with a circular, distinctly raised rim that is covered by similar but even longer fringes than those seen on the outer margin. General colour plain ochraceous mid brown to sepia brown, the fringes of the raised network of the capsule more yellowish tone and the outer margin of the micropylar plate as well as the micropylar cup darker brown. Measurements [mm]: Length incl. operculum 3.9, length 3.5, width 2.5, height 2.8, length of micropylar plate 2.5.

Variability. – There is not too much morphological variability seen in cervicornis . The examples from the island of Samar are all on the smaller side of the size range of the species. Essentially all elements of cephalic, thoracic and abdominal armature are subject to slight variability, which however mostly restrict to the size of the individual spines, which also concerns to the spines of the hind legs in ♂. In ♀ the second paired posteriors are always present on abdominal terga II-IV but in some samples, there is an additional, smaller pair on tergum V (e. g. the specimens from Tiwi, Lagonoy, Mount Banahao and Mount Mayon ). This is also the case in two of the ♂ from Lagonoy and one of the captive reared ♂ from the Pocdol Mountains has all second paired posteriors notably reduced and only represented as rather obtuse tubercles. While the pronotal anteriors are frequently bifid, there is an additional but smaller third posterior spike in a ♀ sample from Pocdol Mountains . Body lengths ♀ 47.5-53.0 mm, ♂ 34.0 – 37.0 mm .

Remarks. – Bolívar (1890) described this species from two syntypes in the collection of MNMS, of which the ♂ bears a lectotype label attached to the specimen by Zompro. The type-status has however never been published. Since the ♀ is the more complete specimens and was illustrated by Bolívar (1890: pl. 5, 5a) it is here designated as the lectotype to ensure stability of Bolívar’s taxon and the new synonymy introduced.Examination of the holotype of Rehn & Rehn’s fratercula , a species described based on a unique ♂ from Tayabas or Butucan in the Quezon Province, as well as a good series of specimens from various localities including the type-locality of fratercula in the collections of RBINS and the author and taking the intraspecific variability into account leave no doubt fratercula is the same species as cervicornis and thus a synonym (n. syn.). Three examples from Lope de Vega in the collections of RBINS and the author represent the first record of cervicornis from the island of Samar. The egg is here formally described for the first time and illustrated ( Fig. 46C - D).

Rehn & Rehn (1939: 477, footnote 84) recorded T. deplanatus from “Surigao” at the extreme north-eastern tip of Mindanao based on a ♀ in the USNM collection but stated that it was not possible to say whether the specimen came from Surigao, Surigao Province or was picked up at some other locality in that province. All records of deplanatus however are from Northern Luzon and this ♀ at first glance differs from true deplanatus by the much smaller triangular mesonotal area. Unfortunately, the USNM specimen was only examined from the illustration provided by Rehn & Rehn (1939, pl. 35: 34), which actually shows it to be misidentified and to come morphologically closest to cervicornis , which is distributed in South Luzon and is also known from the island of Samar, that is situated between Luzon and Mindanao. However, since there are no other known records of Tismaenus from the island of Mindanao, this locality must for now be regarded as questionable.

Culture stock of this species has originally been misidentified and was erroneously distributed as “ Tisamenus deplanata ‘Pocdol’. The first specimens were collected by Thierry Heitzmann ( Philippines) in 2010 on Mount Pulog, Pocdol Mountains, Sorsogon province, Bicol, South Luzon. Further specimens were found in November of the same year on Mount Osiao, a peak in the same mountain range ( Dräger, 2012: 14). Eggs have been sent to Europe on several occasions and Bruno Kneubühler ( Switzerland) appears to been among the first enthusiasts to successfully breed T.cervicornis on bramble ( Rubus pp., Rosaceae ) in Europe.It has since proven very easy to maintain in culture and has been attributed culture No. 399 by the Phasmid Study Group.

Distribution. – S-Luzon: Bicol Region: Province Camarines Sur [MNMS – type locality]; Caramoan Peninsula, Lagonoy [FH]). Bicol Region: Province Sorsogon (Pocdol Mountains, Mount Pulog [FH, RBINS]; Mount Osiao ( Dräger 2012: 14)). Bicol Region: Province Albay (Mount Mayon, Tabaco [FH]; Tiwi [FH]; Guinobatan [photographic record by Albert Kang: https://inaturalist.ca/observations/ 61550236]). Province Quezon (Tayabas, Butucan [ANSP – type locality];Tayabas, Mount Banahao [FH]; Ligao [photographic record by Albert Kang: https://www.jungledragon.com/image/53972/ stick_insect_phasmid_-_tisamenus _deplanata .html]). N-Samar: Province Northern Samar (Lope de Vega [FH, RBINS]). Bohol: Bilar [photographic records: https://inaturalist.ca/observations/127496027, https:// inaturalist.ca/observations/127496017].

The record from Surigao, Mindanao by Rehn & Rehn (1939: 477) based on a specimen in the collection in USNM is doubtful (see above and remark on distribution of the genus Tisamenus ).