Caribbean pygmy jumping leaves (Tetrigidae, Cladonotinae, Choriphyllini)

The tribe Choriphyllini Cadena-Castañeda & Silva, 2019 consists of only two genera, Choriphyllum Serville, 1838 and Phyllo-tettix Hancock, 1902b, combining leaf-like Caribbean wide-nosed pygmy grasshoppers (Tetrigidae, Cladonotinae). The genus Choriphyllum has four species, C. bahamense Perez-Gelabert & Otte, 1999 from the Bahamas (Hummingbird Cay Island), and C. sagrai Serville, 1838, C. saussurei Bolívar, 1887 and C. wallaceum Skejo, Kasalo & Yong, sp. nov. from Cuba. The gender of C. ba-hamensis is changed to C. bahamense in order to match the grammatical gender of the genus, which is neuter. Silva’s designation of C. sagrai , the type species of Choriphyllum , as nomen dubium in 2019 was incorrect as Serville’s drawing clearly points to this spe - cies, endemic to Cuba, so nothing about its identity is doubtful. The genus Phyllotettix is endemic to Jamaica, where four species live: P. rhombeus (Felton, 1765), P. foliatus (Hancock, 1902a), P. compressus (Thunberg, 1815) and P. plagiatus (Walker, 1871), comb. nov. of Choriphyllum plagiatum . Choriphyllum westwoodi Hancock, 1902a, syn. nov. is synonymous with Phyllotettix rhombeus and not with P. compressus . A new subgenus is established, Phyllotettix ( Rhombotettix ) subgen. nov. for P. ( R. ) plagiatus comb. nov. and P. ( R. ) rhombeus . A new species complex, Phyllotettix ( compressus ) sp. complex nov. is established for two morphologically close species, P. compressus , and P. foliatus ; while another new species complex, Choriphyllum ( sagrai ) sp. complex nov. includes C. sagrai and C. wallaceum sp. nov. An annotated key to genera, subgenera, species groups and species is provided.


Introduction
Wide-nosed pygmy grasshoppers (Tetrigidae, Cladonotinae) include species of rather unique morphology, but their taxonomy was pretty chaotic till recently (Tumbrinck 2014).With the photographs of the name-bearing specimens becoming publicly available online on websites such as Orthoptera Species File (Cigliano et al. 2022), it is becoming easier to assess the taxonomy of old species and to identify new records.
The tribe Choriphyllini was established recently (Silva et al. 2019) to gather all leaf-like Cladonotinae from the Caribbean region.The tribe includes only two genera, Choriphyllum Serville, 1838 andPhyllotettix Hancock, 1902b, currently with three and four species, respectively.Starting with the description of P. rhombeus

Materials and methods
Original descriptions (Serville 1838;Bolívar 1887;Hancock 1902a, b;Perez-Gelabert and Otte 1999) of all the species were consulted and type specimens (or photographs of type specimens) of all the described species were examined.Previous synonymisation (Kirby 1910) and nomen dubium designation (Silva et al. 2019) were re-checked and are discussed.A new record of Phyllotettix compressus (Thunberg, 1815) from iNaturalist and new records of Choriphyllum sagrai Serville, 1838 from the field and from museum collections are included.One new species is proposed, C. wallaceum Skejo, Kasalo & Yong, sp.nov.from Cuba, based on a male holotype from MNCN.Taxonomy follows the recent classification of Cladonotinae used in the Orthoptera Species File (Silva et al. 2019;Cigliano et al. 2022;Deranja et al. 2022).Terminology and measurements follow Devriese (1999) and Tumbrinck (2014), except that we introduce the term capital sinus for the sinus between the anterior projection of the pronotal crest and the lateral vertical edge of prozona/paranota (see Fig. 3).The most important taxonomic character in Choriphyllum and Phyllotettix is the shape and undulation of the pronotal crest, i.e.(a) the shape of the anterior projection, (b) the position of the highest point and (c) the shape of the pronotal tip.
The measurements were made using the ImageJ (v.1.53t) software (Schneider et al. 2012).The information on the size of the specimens represented by drawings in Westwood (1839) was deduced using the information in the text (8 lines = 18 mm).
For each genus, we propose a vernacular name, list synonyms and type species and present composition, distribution and a brief generic diagnosis.For the new subgenus, we designate the type species, propose vernacular names and present composition, distribution and brief diagnoses.We define a species group as a category containing species with many similarities, but also with enough differences that make synonymisation impractical without more evidence; the specific status of each species is preserved and their close relationships are reflected by the groupings.For each species group, we propose a vernacular name and provide annotated distribution data and a brief diagnosis.For each species, we propose a vernacular name, present detailed taxonomic and nomenclatural history, information on type specimens and new records, annotated distribution data and a brief diagnosis.Distribution (Fig. 2).Known only from the type locality, small Hummingbird Cay Island (Perez-Gelabert and Otte 1999; Silva et al. 2019).Due to the very small area of occupancy and extent of occurrence, as well as the affinity towards the rainforest habitat, the species might be endangered, but this has to be assessed through fieldwork.There are no new records since the description.
Diagnosis (Figs 1,3).Choriphyllum bahamense can be differentiated from its congeners by: (1) the caudal tip of the pronotum which reaches the tips of the hind knees,  but not beyond (reaches behind the hind knees in C. (sagrai)), (2) the shape of the caudal tip of the pronotum which is excised vertically (in C. (sagrai) and C. saussurei excised at an angle) and (3) the moderate concave slope of the caudal margin of the crest (in C. (sagrai) the crest is higher, convex and sharply sloped and, in C. saussurei, it is lower and concave, but more sharply sloped, with a strong undulation).
Choriphyllum (sagrai) complex nov.3).Members of the Choriphyllum (sagrai) complex can be differentiated from their congeners by: (1) the caudal tip of the pronotum which reaches beyond the hind knees (reaches the tips of the knees in C. bahamense and C. saussurei), (2) the shape of the caudal tip of the pronotum which is excised at an angle (excised vertically in C. bahamense) and (3) the high, convex and sharply sloped crest (in C. saussurei, it is low, concave, sharply sloped and bears an undulation and in C. bahamense, it is of medium height, concave and moderately sloped, without an undulation).Type locality.Cuba, without specified location (Serville 1838).
Diagnosis (Figs 1, 3, 7).The highest region of the pronotal crest is rounded (shaped as a slanted plateau, more angular in C. wallaceum sp.nov.).Anterior to the highest point, with a long, but shallow depression (with very low undulations in C. wallaceum sp.nov.).Posterior to the highest point, the crest with a well-expressed convexity, semicircular (sloping down in an almost straight fashion in C. wallaceum sp.nov., with weak undulations).Legs are generally smoother than in C. wallaceum sp.nov.
Comments.The identity of the species is not questionable (See Figs 1-3, 7).
Etymology.Named after Alfred Russel Wallace, the father of biogeography, modern evolutionary thought and a contributor to many fields of biology.The species name is a neuter gender adjective, second Latin declension, derived from Wallace, i.e. wallaceus, wallacea, wallaceum.
The specific epithet celebrates the 200 th anniversary of Alfred Russel Wallace birth (8 January 1823).Type locality.Cuba, no specific location/s known.
Distribution (Fig. 2).Wallace's Cuban Dancing Leaf lives in Cuba, but the specific location is still not known.

Diagnostic description (Figs 1, 3, 4).
Head.Same as in other members of the tribe.Convex bulging vertex, frontal costa forks into a wide scutellum below half the height of the eye, upper margins of antennal grooves at the level of the bottom margin of the eyes.
Pronotum.General shape close to that observed in C. sagrai, but visibly more angular.The highest region of the pronotal crest is above the humeral angles and is shaped as a slanted plateau (rounded in C. sagrai).Anterior to the highest point, the crest slopes down with barely perceptible undulations (a long, but shallow depression present in C. sagrai).Posterior to the highest point, the crest slopes down with slight undulations (one well-expressed convexity in C. sagrai).
Legs.Anterior femora a little expanded proximally, bearing a tubercle at the middle of the ventral margin.Middle femora with slightly undulated margins, ventral margin with a slight tubercle at the distal third of its length.Hind femora robust, dorsal margin elevated in the anterior half and sloping down towards the knee; one moderate protrusion before the antegenicular tooth.Antegenicular tooth moderately expressed, genicular tooth strongly expressed.Legs are generally rougher than in C. sagrai.
Note.The diagnostic description presented here implies that the diagnostic criteria of higher taxa that encompass this species apply as well and are, thus, considered sufficient to differentiate C. wallaceum sp.nov.from other species.

Choriphyllum saussurei Bolívar, 1887
Vernacular Distribution (Fig. 2).The Cuban Wavy Dancing Leaf inhabits Cuba (Trinidad, Sierra del Grillo and Escaleras de Jaruco) and Isla de Pinos (Gundlach 1891, this study) where it can be found mostly in the mountains, where it dwells in the leaf litter (Gundlach 1891).This species is endemic from west-central Cuba.
Diagnosis (Figs 1, 3).Choriphyllum saussurei can be differentiated from its congeners by: (1) the caudal tip of the pronotum which reaches the tips of the hind knees, but not beyond (reaches behind the hind knees in C. (sagrai)), (2) the shape of the caudal tip of the pronotum which is excised at an angle (excised vertically in C. bahamense) and (3) the low, concave, sharply sloped caudal margin of the crest with a strong undulation (in C. (sagrai) the crest is higher, convex and sharply sloped and, in C. bahamense, it is higher, concave and moderately sloped).
Measurements.See Table 1.3).The anterior margin of the pronotum is undulated (smooth in Choriphyllum).The capital sinus is short, shallow and wide.The highest point of the pronotum is behind the middle (before the middle or in the middle in Choriphyllum).Apex of the pronotum oblique or sharp (strongly truncated in Choriphyllum).
Diagnosis (Figs 1, 3).In lateral view, the posterior margin of the pronotal crest is excised and/or convex (in Rhombotettix subgen.nov., it is obliquely projected and undulated); the pronotum caudally barely reaches the hind knees (reaching behind the hind knees in Rhombotettix subgen.nov.).

Phyllotettix (compressus) complex nov.
Vernacular name: Jamaican Complex Jumping Leaves.Figs 1, 2).The complex includes two very similar species, P. compressus and P. foliatus, which are endemic to Jamaica.The complex may include more undescribed species, but may also represent a single variable species whose variation has not been correctly assessed yet.

Composition and distribution (
Diagnosis (Figs 1, 3).The tip of the pronotum does not reach behind the hind knees.Pronotum rectangular/ rhomboid in shape.In lateral view, the anterior margin of the pronotum may be more or less undulated, while the posterior margin of the pronotal crest is excised or convex.The posterior tip of the pronotum is sharp.Type locality.Jamaica, without specified location (Thunberg 1815).
Diagnosis (Figs 1, 3).Very similar to Phyllotettix foliatus, which is a member of the same species group.Separated by the narrow and sharp highest point of the pronotum (wide and oblique in P. foliatus) and after it, the posterior margin of the pronotum is strongly convex (almost straight in P. foliatus).
In the other two females, the highest point of the pronotal crest is more elevated in lateral view, with a width of 2 mm and 3.5 mm, respectively, slightly undulated at the top; and due to this elevation, the posterior margin of the pronotal crest is strongly undulated in the lateral view.(…) In the case of the male specimen, the pronotum is bluntly rounded and without convexity when viewed in profile.The antennae length of these animals is striking, 8 mm in the examined material"; Silva et al. 2019: 4, 9 (types not found in ANSP, included in the key).Taxonomic and nomenclatural history.
Zaphyllonotum foliatum Caudell, 1909:113 (mentioned  Distribution (Fig. 2).The Jamaican Straightedge Jumping leaf inhabits Jamaica.No specified localities are known hitherto (Hancock 1902a;Silva et al. 2019).However, Josef Tumbrinck has uploaded photographs to the OSF (Cigliano et al. 2022) of two specimens from Hardwar Gap, Blue Mountains, collected by C. W. O'Brien, who noted that the species was found feeding on lichens on tree trunks at night.Phyllotettix compressus has been reported from the same mountain range (see above).
Diagnosis (Figs 1, 3).Very similar to Phyllotettix compressus, which is a member of the same species group.Separated from P. compressus by the wide and oblique highest point of the pronotum (narrow and angular in P. compressus) and after it, the posterior margin of the pronotum is almost straight or weakly convex (strongly convex in P. compressus).
Etymology.Rhombotettix is a noun of masculine gender made up of combining Latinised Ancient Greek words for rhombus (ῥόμβος, rhombos) and grasshopper (τέττιξ, tettix).This name was selected because of its prosody in the combination with the specific epitheton of the type species, "rhombeus".
Distribution (Fig. 2).The Jamaican Triangular Jumping Leaf is endemic to Jamaica, no precise localities are known.
Diagnosis (Figs 1, 3).Similar to Phyllotettix (Rhombotettix) rhombeus, but easily separated by the shape of the anterior and posterior margins of the pronotum, as seen in the lateral view.The most produced anterior part of the pronotum is just above the head, not the one on the dorsal margin as in R. rhombeus.The pronotal crest is tri-Table 1. Comparative measurements of the Choriphyllini members.Measurements shown in the brackets were taken from the type specimen drawings.Note the huge size of Phyllotettix rhombeus pronotum.Abbreviations HT -holotype, PT -paratype, ST -syntype.

Species and specimen
Body length
Holotype ♀ of Choriphyllum westwoodi (plate 1, fig. 2  Distribution (Fig. 2).The Jamaican Colossal Jumping Leaf is endemic to Jamaica, but no precise localities are known.We can suppose that it still lives in the leaf litter of the Jamaican rainforests.
Diagnosis (Figs 1, 3, 5, 6).Similar to Phyllotettix (Rhombotettix) plagiatus, but easily separated by the shape of the anterior and posterior margins of the pronotum, as seen in the lateral view.The most anteriorly projected anterior part of the pronotum is not the one that hangs over the head, as in R. plagiatus, but the projection on the anterior portion of the pronotal crest.The pronotal crest is rectangular and abruptly falls towards the tip after its highest point.

Discussion
World's largest tetrigid "comes home" Phyllotettix (Rhombotettix) rhombeus (Felton, 1765), a species first assigned to Cicada (Felton 1765; Linnaeus 1767), then to Membracris (Fabricius, 1775), Hymenotes (Westwood, 1839), Acridium (de Haan 1843), Choriphyllum (Thomas 1873; Bolívar 1887), has just recently found its home amongst the members of the genus Phyllotettix (Bruner 1910;Silva et al. 2019).This is the first leaf-like tetrigid, described just 7 years after Linnaeus' 10 th edition of Systema Naturae (Linnaeus 1758).There was a huge problem with the generic assignment and the authorship of Phyllotettix rhombeus.Even Silva et al. (2019: p4) incorrectly cited Linnaeus as the species' author in one place of their manuscript.Our study is the first one ever to consistently use the correct generic combination and the correct authorship, that being Felton 1765, not Linnaeus, Backer, Baker, Fabricius, Westwood or Walker (see taxonomic and nomenclatural history under the species).
The Jamaican Colossal Jumping Leaf indeed is a "colossus".Its pronotal length reaches almost 3 cm and its height reaches almost 2 cm, making it the unrivalled world's largest Tetrigidae species known to date.The second largest is the Malagasy Holocerus devriesei, with a pronotum length of a little bit more than 2.5 cm (Skejo et al. 2020).This could be an example of island gigantism (e.g.Raia and Meiri (2006); Lokatis and Jeschke (2018)).Despite being the largest and the longest-known leaf-mimic pygmy grasshopper, nothing is known about the ecology or distribution of this extraordinary taxon from Jamaica.Except for its description, only one more specimen was reported (Westwood 1839;Hancock 1902a Plate I, fig. 2

, as Choriphyllum westwoodi).
We assembled measurements by comparing those obtained from museum specimens with Westwood's (1839) drawings.We deduced information about the size of Phyllotettix rhombeus indirectly, as it was not cited directly in Westwood's (1839) text.Hymenotes triangularis and Choriphyllum sagrai were drawn in visibly different sizes, but next to each of them was the same scale of 8 lines (= 18 mm).We concluded that the lines represent the relevant measure and compared the scale of the aforementioned species with the scale drawn next to P. rhombeus, which we determined to represent about 13 lines (= about 29 mm).
Choriphyllini taxonomically sorted a little better than before All the members of the tribe Choriphyllini are reviewed and a new subgenus (Rhombotettix subgen.nov.), new species groups/complexes (Phyllotettix (P.) (compressus) sp.complex nov.; Choriphyllum (sagrai) sp.complex nov.) and a new combination (Phyllotettix (Rhombotettix) plagiatus comb.nov.) are proposed in order to try to reflect the evolutionary history of this interesting taxon, as observed from morphological similarity.The species complex was established in order to clearly point out that the species included in it share many morphological characteristics and have extremely small differences, so it is not clear whether they have separate evolutionary histories.
Choriphyllum sagrai is not a nomen dubium (Silva et al. 2019), as Serville's (1838) description and drawings clearly match the species found in many localities in Cuba, some of them reported herewith.Choriphyllum sagrai was, however, hiding one secret, as the specimen identified some time ago by the first author as this species, deposited at the MNCN, was found to represent a separate species closely related to C. sagrai, C. wallaceum sp.nov., described in this study.
The newly-described species and the existence of Choriphyllum bahamense on the tiny and low island of Hummingbird Cay in the Bahamas imply that more Choriphyllum species are to be found in the future.The huge diversity of Phyllotettix in Jamaica, based on a few specimens only, provides even stronger evidence that we are still in the very beginning of understanding the Caribbean Pygmy Jumping Leaves.
Is the Phyllotettix (Phyllotettix) (compressus) complex only a single species or two or three closely related species?We can only speculate from four museum specimens, a drawing and a photograph of a living individual.Hence, at this moment, synonymisation or new species establishment would not bring any solution, but instead, introduce more chaos into an already loosely founded system.For Phyllotettix (Rhombotettix) plagiatus comb.nov.and P. (R.) rhombeus little can be said, as the holotypes, unfortunately, remain the only specimens from which information can be extracted.
The long history of this small tribe illustrates how mistakes accumulate when there is a lack of material which is badly handled as well.Previous authors did not all have the means to carefully examine the material or were unaware of its existence, leading to confusing synonymies (e.g.Hancock (1902a)).Silva et al. (2019) provided a good starting point for examining these tetrigids, but overlooked some important data, leading to muddying of the taxonomy in some places, most notably in the case of C. sagrai.Well-discussed taxonomic acts, especially when dealing with making a taxon a synonym or a nomen dubium, are an absolute must in order to avoid future errors.

Next steps in the Caribbean Pygmy Jumping Leaves research
A lot of the crucial information on the Caribbean pygmy jumping leaves is still lacking, despite the two-anda-half-century-long research tradition (from Felton 1765 to Silva et al. 2019).This research tradition did not age well, so that data on the true species' distribution remains almost entirely absent.Scientists can still deal only with imprecise locality data for some species, such as "Jamaica" for Phyllotettix (Rhombotettix) rhombeus and P. (R.) plagiatus (Felton 1765;Westwood 1839).
Citizen scientists in the Caribbean should be encouraged to collect observations of these grasshoppers and consequently, the citizen science platforms, such as iNaturalist, should be regularly monitored by scientists in order to establish and maintain a continuous research practice.Such practice is already proven to work (e.g.Mesaglio et al. (2021); Connors et al. (2022)).
The aim of future research should be collecting more specimens, so our hypotheses on the species and their positions may be tested.Museum collections should be investigated as well to see whether there are more undocumented species/specimens.Fieldwork in the Caribbean region is necessary.Only fresh samples may provide a predisposition for the next step, an evolutionary study by means of molecular phylogeny.By bringing these charismatic critters to public attention and making their identification easier, we hope to foster a wider interest in them.

Figure 1 .
Figure 1.Diversity of the Caribbean Pygmy Jumping Leaves, tribe Choriphyllini, genera Choriphyllum and Phyllotettix.All the specimens with available photographs are shown, representing the first variability assessment for the species of these genera.The scale bar represents 5 millimetres.Serville, 1838, C. wallaceum sp.nov.and C. saussurei Bolívar, 1887 are found only in Cuba.Diagnosis (Figs 1, 3).The anterior margin of the pronotum is smooth (undulated in Phyllotettix).The capital sinus is long, deep and narrow.The highest point of the pronotum is before the middle or in the middle of the pronotum length (behind the middle in Phyllotettix).Apex of the pronotum strongly truncated (oblique in Phyllotettix (Rhombotettix) subgen.nov.or sharp in Phyllotettix (Phyllotettix) members).

Figure 3 .
Figure 3. Annotated schematic pictorial key to genera and species of Choriphyllini.Specimens are not to scale; for size comparison see Fig. 1.The red line shows the position of the highest point of the pronotal crest.The blue arrow points to the anterior margin of the pronotum; the green arrow points to the posterior pronotal tip; and the purple arrow points to the caudal margin of the pronotal crest.Shown are silhouettes of the type specimens of each species.For C. sagrai, shown is the silhouette of Serville's (1838) drawing of the holotype.The capital sinus is marked in red and pointed out in grey.

Figure 2 .
Figure 2. Biogeography of the Caribbean Jumping Leaves (Cladonotinae, Choriphyllini).Biogeographic data of the tribe Choriphyllini is scarce.The distribution map of the six species belonging to this leaf-like tribe has the distribution of three species missing, as no localities are known.

Figure 4 .
Figure 4. Wallace's Cuban Pygmy Dancing Leaf, holotype male from MNCN photo M. París (A), its labels (B) and a photograph of Alfred Russel Wallace (C) after whom the new species was named.
in Hancock 1902a = Hymenotes rhombea depicted in fig.67: 2, 2a, b in Westwood 1839) (probably in BMNH, but the locations of the specimens were not mentioned by Hancock (1902a) who established a new based on its appearance).

Rambur, 1838 Subfamily Cladonotinae Bolívar, 1887 Tribe Choriphyllini Cadena-Castañeda & Silva, 2019
Museum abbreviations are listed as follows: Phyllotettix with four species endemic to Jamaica and Choriphyllum with three species endemic to Cuba and one species endemic to the Bahamas.The genus Phyllotettix is herewith divided into two subgenera (nominotypical Phyllotettix and new Rhombotettix subgen.nov.).