Trolicaphyllium sarrameaense ( Groesser , 2008) Cumming & Tirant & Bu ̈ scher, 2021

Cumming, Royce T., Tirant, Ste ́ phane Le & Bu ̈ scher, Thies H., 2021, Resolving a century-old case of generic mistaken identity: polyphyly of Chitoniscus sensu lato resolved with the description of the endemic New Caledonia Trolicaphyllium gen. nov. (Phasmatodea, Phylliidae), ZooKeys 1055, pp. 1-41 : 1

Trolicaphyllium sarrameaense ( Groesser, 2008) comb. nov.

Figures 1 , 3 , 4A , 4C , 5A, C , 6A, C , 7A , 8A , 9A , 10A , 11A , 12B , 13A, B , 15A-C , 16A-C , 17A-D , 18A , 19 , 20 , 29

Material examined.

(8 ♀♀, 9 ♂♂, 3 eggs): Holotype and paratypes examined: 1 ♀, 1 ♂, 3 eggs: " Chitoniscus , sarrameaensis, Neu Kaledonien, Sarramea, Sep. 2006, det. Größer” (SDEI: HT ♀, DEI Hemimetabola #100215; PT ♂, DEI Hemimetabola #100214; PT eggs, DEI Hemimetabola #100216); (SDEI; Figs 7A , 8A , 13A, B , 29 ).

See Suppl. material 1 for additional specimens reviewed, their collection data, and depositories.

Remarks.

As it was only described in 2008, this was the most recently described species from New Caledonia with type material originally collected by Sigetake Suzuki in 2004 from Sarramea ( Größer 2008a). Within the original description this species was not explicitly compared with the sympatric and morphologically very similar Trolicaphyllium erosus comb. nov. but was instead only differentiated from Chitoniscus lobipes Redtenbacher, 1906, where most features given for differentiation were simply the features we discuss above as significant for differentiating the two genera.

Other lobed specimens have been recovered from throughout New Caledonia, but unfortunately most have been nymphs (such as several from within the QM collection) and therefore they could not be confidently identified as Trolicaphyllium sarrameaense comb. nov. or as Trolicaphyllium erosus comb. nov. nymphs. Unfortunately, in Größer (2008b) the key to species of Chitoniscus sensu lato tried to use the female tegmina radial and media venation pattern to differentiate species, but mixed up the species. Within the key Trolicaphyllium erosus comb. nov. and Trolicaphyllium brachysoma comb. nov. (from New Caledonia) instead key out as the Fijian population and Chitoniscus lobiventris (Blanchard, 1853) and Chitoniscus lobipes Redtenbacher, 1906 (from Fiji) key out as the New Caledonian population. We have reviewed the type specimen photos available on the Phasmid Species Files ( Brock et al. 2021; http://phasmida.speciesfile.org) as well as numerous museum specimens, and always the female tegmina venation allowed accurate distinction of these two genera. Even if you look past this inaccuracy within the key, unfortunately no additional features can be gleaned from the further couplets to allow differentiation of Trolicaphyllium sarrameaense comb. nov. from Trolicaphyllium erosus comb. nov. (as the further couplets discuss abdominal shape, which in these two species is identical/variable). At this moment in time, we still lack significant details about the population of Trolicaphyllium gen. nov. on Grande Terre as material is limited and molecular data has yet to be compared across a wide sampling on the island. With phylliid abdominal shapes sometimes rather variable within a single species, this makes us wonder if Trolicaphyllium sarrameaense comb. nov. is in fact a valid species, or simply a synonym of Trolicaphyllium erosus comb. nov. which was described more than 100 years previously from the same island. Our examination of all type specimens which could be traced has not yet revealed additional features for morphological differentiation besides the overall size of these two species. Hopefully, future molecular analyses from across New Caledonia will reveal if there are several species present on Grande Terre or if it is simply a single species which can range in size from smaller (ca. 40 mm; Trolicaphyllium erosus comb. nov.) to larger (ca. 60 mm; Trolicaphyllium sarrameaense comb. nov.). It is due to this lack of sound molecularly based evidence and the propensity for phylliids to be morphologically variable that we refrain from synonymizing Trolicaphyllium sarrameaense comb. nov. with Trolicaphyllium erosus comb. nov. as we feel a significant decision such as this should be based upon a solid foundation. If future molecular analyses reveal that there is only a single morphologically variable species of Trolicaphyllium gen. nov. on Grande Terre based upon a sampling throughout the island, then we feel a synonymization will be necessary, but not until that time.

The etymology given in the original description is that this name is a toponym, named after the type locality, Sarramea, New Caledonia ( Größer 2008a). The original combination was with the masculine genus ( Chitoniscus ) and therefore in order for the species name to agree in gender with our newly erected genus, the spelling of " sarrameaensis " is changed to the neuter gender " Trolicaphyllium sarrameaense ".

Differentiation.

Females can be differentiated from Trolicaphyllium brachysoma comb. nov. based upon abdominal shape, as Trolicaphyllium brachysoma comb. nov. are considered to have a spade-shaped abdomen, with smooth margins, versus Trolicaphyllium sarrameaense comb. nov. which has a broad abdominal shape with parallel sides, ending in lobed segments VII and VIII. From Trolicaphyllium erosus comb. nov. the only feature we have been able to identify as useful is the overall length, with Trolicaphyllium erosus comb. nov. ca. 40 mm long versus Trolicaphyllium sarrameaense comb. nov. ca. 60 mm long.

Unfortunately, males of Trolicaphyllium brachysoma comb. nov. and Trolicaphyllium erosus comb. nov. have never been confidently confirmed through breeding or molecular comparison. Based upon the confidently confirmed male/female Trolicaphyllium sarrameaense comb. nov. however, we expect that the male morphology should mirror the female morphology. Most likely the male Trolicaphyllium brachysoma comb. nov. will lack prominent abdominal lobes and the male Trolicaphyllium erosus comb. nov. will have distinct lobes to match with their female counterparts. Based upon the female Trolicaphyllium erosus comb. nov. smaller size, we expect that the male must also be rather small, which could likely be used as a feature for differentiation.

Distribution.

To date we have only confirmed adult specimens and observations which are the correct morphology and size of Trolicaphyllium sarrameaense comb. nov. from central Grande Terre (Fig. 21 ). We have however seen nymph specimens which had characteristically lobed abdomens which may represent this species from other locations on Grande Terre, so we expect this species may be widespread throughout the island.

Within the MZPW collection there is a pair of Trolicaphyllium sarrameaense comb. nov. specimens with the data of simply “Lifu”, which if true could lend credibility to the hypothesis that perhaps these species are all variable in their abdominal shape (if there is only one species present on Lifou island), but as these are antique and give no other data, we do not take these as highly credible, and therefore exclude this record from further discussion and they are not included within the distribution map (Fig. 21 ). Or it is possible Lifou island holds several morphologically different species.

Figures

Figure 1. Dorsal habitus of a live adult female Trolicaphyllium sarrameaense comb. nov. photographed by Thierry Salesne (New Caledonia) in March 2011, in Vallee Pierrat, La Foa, Grand Terre.

Figure 3. Adult female Trolicaphyllium cf. sarrameaense comb. nov. found feeding on Syzygium cumini Sarramea county, near La Foa, January 2021 (recorded and photographed by Sylvie Cazeres (IAC )) A dorsoanterior, habitus B dorsal, habitus.

Figure 4. Scanning electron micrographs of female antennae A, C Trolicaphyllium sarrameaense comb. nov. B, D Chitoniscus sensu stricto A, B overview of the antenna, medial view A right antenna B left antenna C, D third antennomere. Abbreviations: a 1 - a 9, antennomeres 1 - 9 st stridulatory file, sr stridulatory ridge. Scale bars: 300 µm (A, B), 200 µm (C, D).

Figure 5. Scanning electron micrographs of female stridulatory organs A, C Trolicaphyllium sarrameaense comb. nov. B, D Chitoniscus sensu stricto A, B overview of stridulatory ridge C, D teeth of stridulatory file. Scale bars: 100 µm (A, B), 20 µm (C, D).

Figure 6. Scanning electron micrographs of female scapus (1 st antennomere) A, C Trolicaphyllium sarrameaense comb. nov. B, D Chitoniscus sensu stricto A, B overview of scapus, lateral view C, D medial view. Scale bars: 200 µm.

Figure 7. Details of the head through thorax, dorsal A Trolicaphyllium sarrameaense comb. nov. (holotype) (DEI Hemimetabola, 100215) B Chitoniscus sp. " Suva " (RC Coll 18 - 176).

Figure 8. Lateral details of the head and thorax A Trolicaphyllium sarrameaense comb. nov. (holotype) (DEI Hemimetabola, 100215) B Chitoniscus sp. " Suva " (RC Coll 18 - 176).

Figure 9. Ventro-posterior view of live females showing their exposed coxae coloration A Trolicaphyllium sarrameaense comb. nov. taken by Thierry Salesne (New Caledonia) March 2011, in Vallee Pierrat, La Foa, Grand Terre B Chitoniscus sp. " Suva " (RC Coll 18 - 176) live photograph taken by Thierry Heitzmann (Philippines).

Figure 10. Female tegmina venation A Trolicaphyllium sarrameaense comb. nov. (Coll SLT) B Chitoniscus feejeeanus from SDEI ( 100213). Abbreviations: Sc (subcosta); R (radius); R 1 (radius 1); Rs (radial sector); R-M (radius to media crossvein); M (media); MA (media anterior); MP (media posterior); Cu (cubitus); CuA (cubitus anterior); CuP (cubitus posterior); 1 A (first anal).

Figure 11. Female genitalia details, ventral view A Trolicaphyllium sarrameaense comb. nov. (Coll SLT) B Chitoniscus sp. " Suva " (RC Coll 18 - 176).

Figure 12. Scanning electron micrographs of tarsi A, C Chitoniscus sensu stricto B Trolicaphyllium sarrameaense comb. nov. A male, overview B, C females, tarsomeres 1 - 5. Abbreviations: ar, arolium, cl, claw, eu 1 - 5, euplantula 1 - 5. Ta 1 - 5, tarsomere 1 - 5, ri, median ridgelike expansion. Scale bars: 500 µm.

Figure 13. Details of male head through thorax A, B Trolicaphyllium sarrameaense comb. nov., paratype male ( 100214); photographs by Arne Koehler (SDEI) C, D Chitoniscus sensu stricto A, C, D head through thorax, dorsal B head through thorax, lateral C Chitoniscus sp. from the NHMUK, photograph by RC D live Chitoniscus sp. " Suva ", photograph by Thierry Heitzemann (Philippines).

Figure 15. Comparison of Chitoniscus sensu stricto and Trolicaphyllium gen. nov. eggs A-C Trolicaphyllium sarrameaense comb. nov., imaged by TB of eggs from Coll DG A dorsal B lateral C opercular (anterior) D-F Chitoniscus sp. " Suva " (RC Coll 18 - 272) D dorsal E lateral F opercular (anterior).

Figure 16. Scanning electron micrographs of specialized chorionic structures of the eggs A-C Trolicaphyllium sarrameaense comb. nov. D-F Chitoniscus sensu stricto A, D overview of micropylar plate B, E detail of micropylar plate C, F micropylar cap. Scale bars: 300 µm (A, D), 100 µm (B, E, F), 50 µm (C).

Figure 17. Scanning electron micrographs of chorionic microstructures on the eggs A-D Trolicaphyllium sarrameaense comb. nov. E-H Chitoniscus sensu stricto A, B mushroom-like granula C, D, G, H surface microsculpture C surface of the granula D exochorionic surface microstructures E, F pinnae. Scale bars: 100 µm (A, E), 20 µm (B, F), 10 µm (G), 5 µm (D), 3 µm (H), 1 µm (C).

Figure 18. Illustrations of freshly hatched nymphs for comparison, dorsal habitus. Illustrations by Liz Sisk (USA). Nymph size is approximated to be relative to each other based upon the few photographs available but is only an estimate A Trolicaphyllium sarrameaense comb. nov.; overall nymph length from head to tip of abdomen approximately 7 mm (Groesser 2008 b); illustration based upon photographs from Detlef Groesser (Germany) B Chitoniscus sp. " Suva' ' based upon images supplied by Mayk de Haan (Belgium).

Figure 19. Captive bred Trolicaphyllium sarrameaense comb. nov. dorsal, habitus, female reared and photographed by Detlef Groesser (Germany).

Figure 20. Trolicaphyllium sarrameaense comb. nov. eggs showing the variation in coloration, photographs by Sylvie Cazeres (IAC), eggs laid by females from Vallee Pierrat, Commune de La Foa A lighter colored eggs B first five eggs laid by the female from Figure 3.

Figure 21. Distribution map noting all presently known Trolicaphyllium gen. nov. records which could be traced and accurately noted. See Suppl. material 1 for full details for all records presented. Stars indicate a record based upon a specimen, circles represent a record based upon a photographic observation. Produced with SimpleMappr (Shorthouse, 2010).

Figure 29. Dorsal habitus Trolicaphyllium sarrameaense comb. nov. A holotype female ( 100215) B paratype male ( 100214). Photographs by Arne Koehler (SDEI). Scale bar: 10 mm.