Research Article |
Corresponding author: Hannelore Hoch ( hannelore.hoch@mfn-berlin.de ) Academic editor: Oana Teodora Moldovan
© 2021 Hannelore Hoch, Alberto Sendra, Sergio Montagud, Santiago Teruel, Rodrigo Lopes Ferreira.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Hoch H, Sendra A, Montagud S, Teruel S, Ferreira RL (2021) First record of a cavernicolous Kinnaridae from the Old World (Hemiptera, Auchenorrhyncha, Fulgoromorpha, Kinnaridae, Adolendini) provides testimony of an ancient fauna. Subterranean Biology 37: 1-26. https://doi.org/10.3897/subtbiol.37.60483
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A new obligately cavernicolous species in the planthopper family Kinnaridae is described from Spain. This is the first record of a cavernicolous kinnarid from the Old World, and the first record of a troglobitic fulgoromorphan hemipteran from mainland Spain, and also the 7th cavernicolous kinnarid species worldwide. Epigean Kinnaridae are not known from the present-day fauna of the Iberian Peninsula nor from Western Europe at large. The new species is regarded as a relict from an ancient fauna which is now extinct. The new cavernicolous species could not be assigned to any of the existing genera, thus a new genus is established. Molecular data (COI barcode sequence) for the new species are presented. For the first time, a detailed description of the nymphal morphology of a kinnarid is provided. Information on its ecology, behaviour, distribution and conservation status is given, and biogeographic implications are discussed.
Caves, conservation, Iberian Peninsula, morphology, taxonomy, troglobite, troglomorphy
During several years of biospeleological research in the cave ecosystems of the Valencian Community (Spain), the former team of biologists from the Museu Valencià d’Historia Natural (Torres Sala Foundation), collected several specimens of a highly troglomorphic species of the planthopper (Fulgoromorpha) taxon Kinnaridae, previously unknown in the Iberian Peninsula. Its discovery received considerable attention in the local media, as the tiny creature is a) morphologically stunning with glassy wings characterized by a shining blue rim in males, evoking images of a ”fairy“, and b) its existence in the dark subterranean spaces of the last remains of Mediterranean forests in Valencia. Thus, this remarkable taxon was named the „fairy of the forests“ (see below, etymology). At the moment, the new species has been studied from two caves, and has been observed in seven other caves, all in the most eastern reliefs of the Iberian Mountain Range in the east of the Iberian Peninsula. The species is characterized by several troglomorphies, e.g., absence of compound eyes and ocelli, very pale body pigmentation and reduced tegmina and wings, and is accordingly assumed to be obligately cavernicolous (troglobitic). This species represents the first record of a troglobitic planthopper species in mainland Spain, the first record of the taxon Kinnaridae in mainland Spain, the 7th cavernicolous kinnarid species worldwide, and the 3rd record of an obligately cavernicolous planthopper in the Mediterranean.
With currently 115 species in 24 genera (
The majority of Kinnaridae species are epigean, with well-developed compound eyes, vivid body coloration, fully developed tegmina and wings, enabling flight. Several lineages, however, are known to have colonized caves in various regions of the New World: the Caribbean (Jamaica:
Knowledge of the biology and ecology of Kinnaridae in general is scarce. Most species are apparently associated with dicots (Asteridae and Dillenidae:
The current state of Kinnaridae classification has been summarized by
The specimens were discovered by visual search, collected by hand, and transferred into vials containing 70% and 96% ethanol. For permanent storage, after dissection and examination, genitalia were transferred to polyethylene vials, and individually associated with the specimen vial.
Measurements and examinations of external body features were made from the specimen in ethanol. To prepare male genitalia for dissection, the genital capsule was removed from the specimen, macerated for 24 h in 10% KOH at room temperature, washed in water, transferred to glycerine for storage or to glycerine-jelly for drawings. Examinations and drawings were made using a Leitz stereomicroscope with a camera lucida attachment.
Specimens preserved in 96% Ethanol were critical point dried with a Leica EM CPD 300, and gold coated for 2, and 4 minutes, respectively. Morphological investigations were conducted with a Zeiss EVO LS 10 electron microscope.
DNA was purified individually from two whole nymphs with a Qiagen Blood & Tissue kit using the manufacturer’s protocol. Polymerase chain reaction (PCR) was used to amplify a mitochondrial gene fragment, a 710 bp fragment of the Cytochrome Oxidase subunit I gene (COI) using primers LCO1490 and HCO2198 (
PCR was performed in 25 μl volumes containing 1× Taq buffer, 1.5 mM MgCl2, 200 μM each dNTP, 1 U Taq polymerase, ca. 50–100 ng DNA and ddH2O. After an initial denaturation step of 3 min at 94 °C, cycling conditions were 35 cycles at 94 °C for 35 s, 45 °C (COI) for 60 s, and 72 °C for 1 min, with a final elongation step of 5 min at 72 °C. The same primers were used in PCR and sequencing. PCR products were sent to Macrogen Europe for purification and cycle sequencing of both strands. The sequences were processed and corrected using CodonCode Aligner v. 5.1.5 (CodonCode Corporation), both nymphs had identical sequences (sharing a single haplotype). The haplotype sequence has been deposited in GenBank, access number MW323405.
Kinnaridae Muir, 1925: 158
Prosotropinae Fennah, 1945: 449
Valenciolenda fadaforesta sp. nov. (type locality: Spain, València, Murciélagos cave).
Small kinnarid (ca. 3–4 mm body length), strongly troglomorphic: compound eyes and ocelli absent, tegmina reduced in length but surpassing lateral body margins, wings vestigial, body whitish, pigmentation largely reduced (Fig.
Valenciolenda fadaforesta sp. nov., habitus, dorsal view a adult male, dorsal view b nymph (IV. instar) from ‘Murciélagos’ cave (Vilamarxant, València) (photos by: Sergio Montagud Alario) c morphological analogy in the troglobitic Solonaima baylissa Hoch & Howarth, 1989 (Cixiidae) from Australia: habitus, adult male, dorsal view. Body length 4.5 mm (photo by H. Reimer, Marburg, used with permission).
Head
(Fig.
Thorax. Pronotum tricarinate, ca. 2.3 × wider than head at level below antennae, short, ca. 5 × wider than medially long, posterior margin shallowly concave; carinae distinct, median carina reaching, but not surpassing anterior margin of pronotum; lateral carinae very shallowly S-shaped, joining hind margin laterally; mesonotum distinctly tricarinate, slightly wider than medially long; tegulae vestigial. Hind tibiae laterally unarmed, distally with 6–7 slender, terete spines, indistinctly grouped (3+4), and forming a shallow arc. First metatarsal joint with 4–5, 2nd metatarsal joint with 3–5 sturdy denticles (bilaterally and individually variable). Pretarsal claws and arolia small, inconspicuous. 2nd and 3rd metatarsal joints together slightly shorter than 1st metatarsal joint. Tegmina (Fig.
Valenciolenda fadaforesta sp. nov. Right tegmen, male. Scale bar: 0.5 mm. Abbreviations: ScP+R+M+Cu, subcosta posterior + radius + media + cubitus; scc, subcostal cell; ScP+RA, subcosta posterior + radius anterior; RP, radius posterior; PCu, cubitus posterior; A1, first anal vein; A2, second anal vein; CuA, cubitus anterior; PCu+A1, cubitus posterior + first anal vein; CuP, cubitus posterior; MP, media posterior; C1-C5, nodal cells.
Male genitalia
(Figs
Females (Fig.
The genus name is a combination of Valencia, the capital city of the Valencian Community, an autonomous region of Spain in the east of the Iberian Peninsula where the type locality is located, and the tribe of Kinnaridae, Adolendini, to which the type species is assigned. The gender is feminine.
Habitus (Fig.
Body length. Measurements refer to distance between anterior margin of head to tip of abdomen (= caudal margin of genital styles in males, and tip of anal segment in the female).
Males. 2.8 (in a specimen with contracted abdominal segments) – 3.8 mm (in the holotype which displays fully extended abdominal segments) (n = 4). Females. 4.1 mm (n = 1).
Colouration. Head, thorax and abdominal segments largely unpigmented, whitish except lateral carinae of frons and rostrum, legs and genitalia in both sexes (genital segment, genital styles, gonocoxae VIII) which are light yellowish. Distal spines on hind tibiae, 1st and 2nd metatarsal joints sordid brown. Tegmina translucent, unpigmented, veins whitish.
Configuration, shape and proportions of head and thorax as described for the genus.
Male genitalia. Genital segment bilaterally symmetrical, in lateral aspect short, narrow in dorsal half, gradually widening caudoventrally; ventrally ca. 3.2 × longer than dorsally. Anterior margin of genital segment smooth, devoid of median apodemes. Genital segment in caudal aspect highly ovate, lateral margins in ventral portion more or less parallel, slightly diverging in dorsal third, dorsally gently arched medially, without conspicuous transverse bridge; caudal margin of genital segment ventrally smooth. Anal segment bilaterally symmetrical, short, stout, caudally on each side with a short, apically rounded, arm-like process directed laterocaudally. Paraproct short, stout, mushroom-shaped; epiproct broadly disc-shaped, laterally wider than paraproct, caudally not exceeding paraproct. Genital styles bilaterally symmetrical, slender at base, apically considerably enlarged; enlarged portion medially deeply concave, bearing 3 apically rounded processes: one arising from ventral margin, directed mediodorsally, the others arising from dorsal margin and directed dorsally and laterodorsally, respectively. Genital styles densely covered with strong setae; setae predominantly on dorsal processes. Connective straight, and narrow. Aedeagus bilaterally symmetrical, short, stout, tubular, ventrally narrow and slightly compressed, distally widening and with ventral margin of strongly sclerotized part produced into a median tip which in repose is pointing ventrocaudally. Periandrium without any spinose or lobate processes; near base laterally on each side with a short, wing-like process, which is connected to the genital segment; apically with a wide membranous portion exposed caudally. Phallotreme not visible. Proximal apodeme of aedeagus („tectiform structure“ sensu
Females with abdominal tergites VI–VIII bearing wax fields. Genitalia with sternite VII in ventral view trapezoidal, with lateral margins diverging caudally, caudal margin smooth, straight; gonocoxae VIII wide at base, distally bilobate with dorsal lobe larger than ventral one, lobes medially converging, both lobes apically with setae; tergite IX in dorsal aspect short, expanding ventrally and forming a continuous sclerotized bridge surrounding the anal segment. Anal segment (segment X) tubular, in dorsal aspect with lateral margins more or less parallel; anal style (segment XI) with paraproct prominent.
Immatures (Figs
V. instar nymph. Body length 2.5 mm (specimen with contracted abdomen) – 3.1, resp. 3.2 mm. (specimens with extended abdomen) (n = 3).
Habitus. Body ca. 1.7 × longer than maximally wide; maximum width at lateroposterior margins of forewing pads. Vertex short, compound eyes absent; rostrum elongate, well surpassing hind coxae, with ca. half its total length; frons, thoracic nota and abdominal tergites IV–VIII with numerous sensory pits.
Colouration. Vertex, frons, thoracic and abdominal nota as well as distal parts of legs (tibiae, tarsi) light yellowish; head laterally, thorax ventrally as well as proximal parts of legs (coxae, femora) and abdomen ventrally white. Carinae of head and lateral carinae of pronotum yellowish brown; distal teeth of metatibia and metatarsomeres dark brown.
Head. Vertex short, ca. 4 × wider than medially long, medially divided by a narrow longitudinal membraneous furrow, separated from frons by a distinct ridged transverse carina which medially slightly arches anteriorly. Frons smooth, without median carina, but with submedian carinae present, arising from frontoclypeal suture, parallel to lateral carinae of frons, converging towards apex and uniting into a short common stem which connects to anterior margin of vertex. Lateral as well submedian carinae of frons and their common stem distinctly ridged; frontoclypeal suture nearly straight, only slightly arching towards frons. Frons ca. 1.2 × as long as maximally wide (widest at level of antennae), apically straight; frons ca. 2.4 × longer than post- and anteclypeus together. Frons between lateral and submedian carinae with two parallel rows of sensory pits, in upper portion with complementary sensory pits between the two rows. Setae of pits directed towards adjacent carinae and those of complementary pits directed towards lateral carina. Post- and anteclypeus smooth, without median carina. Tip of rostrum with dorsal and ventral sensory fields convex, as described by
Valenciolenda fadaforesta sp. nov., V. instar nymph (SEM) a head and pronotum, dorsal view b head, ventral view c left antenna, dorsal view d head (partim) with antenna, left lateral aspect; arrow indicates the former position of the compound eye e tip of left antenna, as in Fig.
Thorax. Pronotum short, in dorsal aspect medially ca. 2 × as long as vertex, and ca. 2 × as wide as maximum width of head; lateral carinae of pronotum nearly straight, strongly diverging posteriorly; „additional carina“ of pronotum (sensu
Valenciolenda fadaforesta sp. nov., V. instar nymph (SEM) a tip of rostrum with sensilla, ventral aspect b metatarsus, ventral view c abdominal segments VI–IX (arrow – see explanation in text). Abbreviations: mx, md, mandible, maxillae; SF-D, dorsal sensory field; SF-V, ventral sensory field.
Abdomen as in other Fulgoromorpha 9-segmented (except for Tettigometridae:
Hitherto, no information on nymphal morphology of Kinnaridae has been available – they are not covered in the seminal works on Fulgoromorphan nymphal morphology,
A blast search in GenBank and BOLD data bases for most similar COI sequence data revealed that Valenciolenda fadaforesta shows 15% divergence to all other Auchenorrhyncha. A molecular phylogeny of Kinnaridae, however, did not seem feasible due to insufficient taxon sampling: all other kinnarid taxa represented in Genbank and BOLD are from the New World (USA, Honduras, Mexico, Costa Rica).
The species name is a combination of the Valencian word for „fairy“ (fada) and forest, thus meaning „fairy of the forest“. The gender is feminine.
Type-locality: Spain, Valencia, Vilamarxant, ‚Murcielagos‘ cave, 39.537095, -0.624732, 5th April 2016, L. Beltran and A. Sendra leg.; in coll.
Type-specimen: Holotype male, preserved in 96% ETOH, polyethylene vial. Original label: “Spain, València, Vilamarxant, ‚Murcielagos‘ cave, (30SYJ0410579181 (UTM/MGRS Datum EUR50), 5th April 2016, L. Beltran and A. Sendra leg.”; printed label (red): “Valenciolenda fadaforesta Hoch & Sendra, holotype male”.
Paratypes. 1 male, same data as holotype. 1 male, 1 female, same locality as holotype, 30th April 2017, S. Teruel and A. Sendra leg; 1 male, same locality as holotype, 24.VI. 2017. 1 male, Spain, Castelló, ‚Coves de Sant Josep´cave, 4th June 2016, S. Teruel leg.
Paratypes in coll. NAT (Museu de Cièncias Naturals de Barcelona, Spain),
1 nymph, V. instar, same data as holotype. 4 nymphs, V. instar, same locality as holotype, 24.VI. 2017;
Specimens of Valenciolenda fadaforesta have been studied in two caves (‚Murciélagos‘ cave and ‚Coves de Sant Josep‘ caves) in two karstic areas of Triassic dolomite separated by 45 kilometers and located in the eastern reliefs of the Iberian Mountain Range, from eleven to twenty-seven kilometers inland from the Mediterranean coast (Fig.
Distribution map of Valenciolenda fadaforesta gen. nov., sp. nov. Localities: 1 ‚Raíces‘ cave, Millares, València 2 ‚Murciélagos´cave (type locality), ‚Pedrizas‘ cave, ‚ Llentiscle‘ cave and ‚Sima del Perot, cave in Vilamarxant, València 3 ‚Cavall‘ cave, Lliria, València 4 ‚Soterranya‘ cave, Serra, València 5 ‚Sima Plà dels Llomes‘, Serra, València 6 ‚Coves de Sant Josep‘ caves, la Vall d’Uixó, Castelló. Dark blue areas mark karst regions. (map modified after
V. fadaforesta displays a configuration of external characters which are certainly troglomorphic traits, such as the absence of compound eyes and ocelli, and reduced body pigmentation as well as tegmina and wings. The species is known exclusively from caves, and it can be assumed that it is restricted to subterranean environments. According to the ecological classification concepts proposed by
Root habitat in `Raices´cave (Millares, València) a overview main room b roots along cracks in the cave ceiling c roots dangling from the ceiling d Valenciolenda fadaforesta sp. nov., adult, on cave floor in `Murciélagos´cave (photos a–c by Teresa Molina Jiménez and Ricardo Giménez Mezquita, used with permission of UEE Fotogrup; photo d by Sergio Montagud Alario).
Although there is no information on the mating behaviour of any kinnarid species, Valenciolenda fadaforesta may utilize the same communication system to locate potential mating partners, as has been documented for other (epigean and cavernicolous) planthoppers, i.e., surface-borne vibrations (Hoch and Howarth 1993,
An amazing similarity in behaviour has been observed in Valenciolenda fadaforesta and an obligate cave species of the family Cixiidae from Australia: Solonaima baylissa Hoch & Howarth, 1989, from Bayliss Cave, a lava tube of Undara lava flow, Queensland (Fig.
Another striking behavior has been observed in the nymphs and adults of V. fadaforesta. When they wander around and also when they remain in the same spot, a quick lateral movement of the abdomen has been observed. Such movement is usually followed by a change in the walking direction which is consistent with that of the lateral abdominal deflection. It could be interpreted as a signal to change the direction of movements, perhaps in response to yet unidentified stimuli.
In order to settle the conservation status of this remarkable endemic genus, two interesting aspects might be considered. Firstly, conservation of the general habitat of Valenciolenda fadaforesta. All caves in the Valencian Community are protected by law (11/94 Law of Natural Protected Spaces and Legal decree 65/2006, of 12th May) devoted to caves with special protection for 150 notable caves, among them there are all the cavities of the ‘Pedrizas’ in the Rodanes karstic area, ‘Soterranya’ and ‘Sant Josep’ caves inhabited by V. fadaforesta. Also, the Rodanes caves are within a natural protected park including the Turia Natural Park. Secondly, V. fadaforesta, according to the IUCN Red Data Book categories ought to be regarded as vulnerable, or even endangered (
There are real threats to the sustained occurrence of V. fadaforesta. Most notably, the species shows a low population density: in almost all caves where it has been reported, only one or a few specimens have been observed. Only the ‘Murcielagos’ cave contains a stable population all year round, but even this population apparently diminished during the extended 2013–2016 drought which affected the flora, with a particular impact on the pine trees, Pinus halepensis. This drought period also impacted the roots that appear inside the cave. Fortunately, after the end of the drought period at the end of 2017 there was an apparent recuperation of V. fadaforesta of the ‘Murcielagos’ cave.
According to the classification of Kinnaridae suggested by
The placement of Valenciolenda into Adolendini follows the concept of tribal division of Kinnaridae by
1) Metope (= frons) without median carina, narrow, with high lateral carinae. According to Emeljanov (personal communication, used with permission) this is an apomorphy, however, with low weight because of high potential for homoplasy.
2) Median carina of pronotum reaching fore carina but not prolonged in front of it.
3) Basal cell of fore wing closed by anastomosis of M and CuA (
However, at least one of these characters (frons smooth, without median carina), is often observed in obligately cavernicolous planthoppers (
Given the background of the current state of knowledge on the phylogeny of Kinnaridae, it is difficult to make conclusions as to which taxa may be the closest living relatives of Valenciolenda fadaforesta. The geographically closest Kinnaridae are species from 2 genera (Kinnacana Remane, 1985 and Kinnoccia Remane, 1985) (tribe Kinnocciini
Except for the Kinnocciini, Kinnaridae have not been documented from Western Europe. Several species are known from Iran, Tadzhikistan (
Although it cannot be determined on the basis of our current knowledge whether initial cave adaptation was driven by allopatry (extinction of closely related epigean populations: see climatic relict hypothesis, as postulated by e.g.,
A similar case of a relict distribution has been documented from the Canary Islands: there, obligately cavernicolous species of the Fulgoromorpha taxon Meenoplidae are known from La Palma (
The unexpected discovery of this planthopper of the Kinnaridae family, Valenciolenda fadaforesta gen. nov., sp. nov., in a relatively well-known Iberian cave highlights the importance of subterranean biodiversity, and leads us to conclude that there are still many amazing discoveries awaiting us in cave environments. The study of cave faunas may yield valuable information on evolutionary and biogeographic history, and thus provide veritable windows to the past.
We would like to express our sincere thanks to Agustín Moreno Navarro and Josep Fernandez Peris, who helped us with the sampling work and also Loles Beltrán Barat, Valencian Health Service, who also helped us with the sampling and brought our attention to the striking movements of the abdomen when the fairy of the forest changed direction. We also thank Carlos Carrión Aranguren and his daughter Gloria Carrión Ortiz who helped us during the visits of the Murciélagos cave, and mostly for sharing with us the enthusiasm in the last year of the study. Also our thanks to Teresa Molina Giménez and Ricardo Gimémez Mezquita from Speleologist United Group, UEU Fotogroup, who helped us to locate and explore ‚Raices‘ cave and also gave permission to use the habitat photographs. We also thank Monica Gallart, writer and designer, who created the distributional map, as well as Sara Teruel Gallart and family who helped us to prepare the videos. We also thank our colleagues from the Museum für Naturkunde, Berlin, Anke Sänger, for her help in SEM studies of the nymphs, Thomas von Rintelen and Robert Schreiber for organizing and performing the DNA lab work, Andreas Wessel for help in organizing the figures, and Jason Dunlop for English language editing. We are also indebted to Thierry Bourgoin, Museum d´Histoire Naturelle, Paris, for discussion on wing venation interpretation, Jacek Szwedo, University of Gdansk, Poland, for information on the fossil record and palaegeography, as well as Alexandr Emeljanov and Vladimir Gnezdilov, Zoological Institute, Russian Academy of Science, St. Petersburg, Russia, Werner Holzinger, University Graz, Austria, and Manfred Asche, Museum für Naturkunde, Berlin, for valuable advice on the taxonomy and for constructive comments on earlier drafts of the manuscript.
Video sequence
Data type: Video sequence
Explanation note: Video sequence documenting Valenciolenda fadaforesta sp. nov. (adult male) in its natural environment (video by Sergio Montagud Alario).