Chlorocoelus hypericifolius ( Stoll, 1813 )

Heller, Klaus-Gerhard & Helb, Matthias, 2024, The tananá [Chlorocoelus hypericifolius (Stoll 1813): Orthoptera, Tettigonioidea, Pseudophyllinae] - re-discovered more than 150 years after the description of the male by Bates and the figuring by Darwin, Zootaxa 5424 (3), pp. 367-376 : 368-372

Species Chlorocoelus hypericifolius ( Stoll, 1813)

syn. Chlorocoelus tanana Bates, 1862 ; Pterophylla brasiliensis Caudell, 1911

Type localities: hypericifolius : Surinam [depository Museum Amsterdam (according to Beier 1960), now Naturalis, Leiden, but not found there (Luc Willemse, email 04.09.2023)]; tanana : Brazil, Brazil North, Pará, Óbidos ( NHM); brasiliensis : Brazil ( MNHN; Serville 1838)

Taxonomic remarks. The genus has a complicated taxonomic history resulting partly from three serious errors (numbered with #). Bates (1862) established the genus Chlorocoelus for his new species C. tanana . He recognized similarities to Locusta camellifolia Fabricius, 1775 and wrote that the same species (of Fabricius) was described again by Serville (1838) under a new genus name, Thliboscelus camellifolius (error in the archive version of OSF 2023, here listed as Thliboscelus hypericifolius ). Serville (1838) explicitly lists Fabricius as reference for his species name. Bates was puzzled by Serville's proposal that Fabricius’ Locusta camellifolia —which he knew from the British Museum in London—occurring in North America and the female specimen Serville was refering to from Brazil should belong to the same species, but he decided that the differences to his specimen were large enough to place them into two different genera. From present knowledge we can assume that Serville was correct in establishing a new genus but misidentified his female as belonging to this new genus (#1). Brunner von Wattenwyl (1895) accepted Thliboscelus with the sole species camellifolius , but incorrectly with Serville as author of the species (#2) instead of Fabricius and transferred Chlorocoelus tanana to Cyrtophyllus , having seen a male and females of the species in the collection of Berlin. However, already in 1825 W. Kirby had introduced the genus name Pterophylla for all species with “tegmina, so beautifully imitate the leaves of plants, distinguished by a recurved ovipositor”. For this vaguely defined group W. J. Kirby (1906) selected unfortunately also Locusta camellifolia Fabricius, 1775 as type species, making Thliboscelus a junior synonym of Pterophylla . Kirby did not see this problem because he followed Brunner von Wattenwyl’s (1895) error for Thliboscelus and listed Chlorocoelus tanana separately. However, the correct consequence was relatively fast recognized by Caudell (1911). In his paper dealing with the errors in Kirby’s (1906) catalogue he accepted the synonymy—as did Rehn (1947) —and proposed a new name for Serville’s misidentified and now nameless specimen ( brasiliensis nom. nov.; again error in the archive version of OSF 2023, not a replacement name for Gryllus (Tettigonia) hypericifolia ) and placed it in Pterophylla . Beier (1960) finally did not accept Caudell’s conclusions (#3), but followed Kirby (1906) in retaining Thliboscelus . In our opinion, however, Caudell (1911) is right in considering Thliboscelus as synonym of Pterophylla , and we have to accept Chlorocoelus as the correct genus name for Bates’s species.

In his book Beier (1960) followed the idea of Burmeister (1838) that the drawing of Gryllus (Tettigonia) hypericifolia by Stoll (1813) (by Brunner von Wattenwyl treated as a synonym of Locusta perspicillata = camellifolia Fabricius, 1775 ) might represent Chlorocoelus tanana and that this name ( hypericifolia ) would have priority. From the proximity of the collecting sites (see below) the assumption seems plausible. Before Beier (1960), the name Chlorocoelus tanana was still used by Kirby (1906) and Rehn (1948).

Examined material. 1 male, Brazil, Amazonas, Nova Olinda do Norte , -3.887778 N, -59.093889 E, native collector; bought in 2022 at Insektenbörse Frankfurt, last from a series of about 10 specimens. Depository; private collection of M. Helb. Measurements; length of pronotum 7.0 mm, of tegmen 43 mm .

Video and sound files: 1 (2?) male(s), French Guiana, Cayenne, Roura, Amazone Nature Lodge (4.5436873 N, -52.1695669 E); Nov. 2015 ( Amazone Nature Lodge 2015a, b)

Published findings. Type localities (see there), 1 male (without data) in Zoological Museum University Heidelberg ( Klee 1961; specimen and complete collections now lost—but see below) ; 3 specimens in MfN Berlin ; 1 male, Brazil, Amazonas, Novo Aripuana (-8.4942 N, -60.961539 E), 2021 10 27, observation Rich Hoyer (iNaturalist https://www.inaturalist.org/observations/101353950)

Existing specimens in collections: 1 male, 2 females ( MfN); type tanana (male)( NHM), type brasiliensis (female) Paris (no information obtainable if still existing), specimen studied here (male) .

The specimens in MfN were first mentioned by Brunner von Wattenwyl (1895). According to the Collection Manager of MfN they are placed under the name Thliboscelus hypericifolius ( Stoll, 1813) and bear the labels: male: 1264 // camellifolius Fabr. , Brasil., Sello. // Thlioscelus Serv; 1 female: viridifolius Serv.; 1 female: no label. The number 1264 refers to entrance book of the museum, giving the data of the male and a ‚3‘ for the number of specimens. Thus probably all three specimens were obtained at the same time. The word ‚Sello‘ may indicate the collector Friedrich Sello, later called Sellow by himself, a famous botanist and naturalist working in Brazil (https://de.wikipedia.org/wiki/Friedrich_Sello), who sent plenty of material to Berlin. He died through an accident in 1831 .

Identification. Chlorocoelus hypericifolius is characterized by its large, inflated tegmina ( Fig. 1 ). However, within Pteropyllini there are a few relatively similar genera all with a large number of parallel veins in the costal area ( Beier 1960). Chlorocoelus and Phyllopectis Rehn differ from the others ( Lea Caudell, 1906 , Paracyrtophyllus Caudell, 1906 and Pterophylla , all from North America) by the short male subgenital plate, simple cerci and (as far as data are available in OSF) glossy mirrors in both tegmina as exemplified in Fig. 2D, E ). C. tanana and P. crepitans ( Redtenbacher, 1892) have been combined under Chlorocoelus until Rehn (1948) erected Phyllopectis . One important discriminative character is based on the structure of the stridulatory area in the left male tegmen, which is bi-partite in Phyllopectis and carries a distinct mirror ( Fig. 2C ) whereas it is strongly sclerotized in Chlorocoelus with a only weakly recognizable mirror (see Fig. 2A, B ).

B Bioacoustics

Stridulatory organs. The stridulatory file (length 5.5 mm) in the underside of the left tegmen consists of ca. 51 teeth whose intervals continuously decrease from tegmen edge towards articulation (tooth intervals ca. 150 to 100 µm; extreme 227 µm to 50 µm; Fig. 3 ). A few very small teeth near the articulation were not included. The mirror cell of this left tegmen is neither glossy nor thin nor transparent but looks quite robust ( Fig. 1 , Fig. 2 ). In contrast, the mirror of the right tegmen is semi-transparent, but does not look to be very thin or glossy (width 5.2 mm x length 4.0 mm; Fig. 2 ).

Sounds. In the video recordings single syllables and several series of disturbance sounds can be heard, produced as reaction to touching the animal. A series contains of several (5–18; mean 12.4; n=5) short syllables with a mean duration (closing hemisyllable) of 35.4±5.3 ms (n=20). Each hemisyllable consists of one narrow-banded sound pulse with a carrier frequency of about 2.1 kHz ( Fig. 4 ). Accordingly the syllables have high quality values (in the second part of a series Q 3dB> 50, Q 10dB> 33). On average, about 74 maxima of the sound wave can be calculated per syllable. The first syllable of a series sometimes has an irregular structure possibly as an effect of the touching.

Figures

FIGURE 1. Habitus of a male Chlorocoelus hypericifolius. A lateral, B dorsal. Scale 50 mm.

FIGURE 2. Male mirror area in some Pterophyllini. A Chlorocoelus hypericifolius, left tegmen, B C. hypericifolius, right tegmen, C Phyllopectis crepitans, left tegmen (OSF), D Pterophylla furcata laletica, left tegmen (OSF), E P. furcata laletica, right tegmen (OSF). Scale A, B 1 mm.

FIGURE 3. Stridulatory file in Chlorocoelus hypericifolius.

FIGURE 4. Sonogram and spectrum of disturbance sounds of Chlorocoelus hypericifolius