Research Article |
Corresponding author: Rochelle Hoey-Chamberlain ( rochelle.hoeychamberlain@ucr.edu ) Academic editor: Laurence Livermore
© 2016 Rochelle Hoey-Chamberlain, Christiane Weirauch.
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:
Hoey-Chamberlain R, Weirauch C (2016) Two new genera of big-eyed minute litter bugs (Hemiptera, Schizopteridae, Hypselosomatinae) from Brazil and the Caribbean. ZooKeys 640: 79-102. https://doi.org/10.3897/zookeys.640.9690
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Charismatic Hypselosomatinae (currently 14 extant and fossil genera; 72 species), the “big-eyed minute litter bugs”, are characterized among Schizopteridae (Dipsocoromorpha) by the large eyes, four-segmented labium, and distinctive wing venation. A recent molecular phylogenetic analysis confirmed the monophyly of Hypselosomatinae that were recovered as the sister taxon to the Ogeriinae + Schizopterinae (
Dipsocoromorpha , taxonomy, morphology, Neotropics, Hypselosomops pecki , Hypsohapsis takiyae
Schizopteridae are tiny (1–3 mm) yet charismatic Heteroptera, the study of which is hampered by their cryptic habits and small size that make them rare in collections and difficult to examine. Adults display extreme wing polymorphism ranging from apterous to macropterous and elytrous, with the latter being a wing type that is very rare outside of Coleoptera. Wing polymorphism can be sexually dimorphic (
The taxonomic history of this group started in the late 19th century with the almost simultaneous description of Old World Hypselosoma oculata Reuter by
The Hypselosomatinae have a worldwide distribution but are most diverse in the tropics, a pattern similar to those observed in other groups of Dipsocoromorpha. The greatest described diversity is from the Indo–Pacific and Australia, but this may be an artifact due to Hill’s focus on that biogeographic region and the lack of research on the Oriental, Afrotropical, and Neotropical regions. Hypselosomatines inhabit cryptic and typically moist microhabitats such as leaf litter, low vegetation, the interstitial zone of streams, and even mangroves (
Map of distribution of all New World Hypselosomatinae (generated using data entered in the American Museum of Natural History’s Arthropod Easy Capture Software database (http://www.research.amnh.org/pbi/locality/index.php))
A single male specimen collected in Sao Paolo, Brazil (BRAZIL: Sao Paulo: Ubatuba: Picinguata; -23.37743, -44.83733; 1997–2001, Nessimain, J.L. & Takiya, D.M.), loaned to us by Daniela Takiya, will be deposited in the Universidade Federal do Rio de Janeiro (
Dorsal, lateral, and ventral habitus images were produced using a Leica DFC 450 C Microsystems system (Leica, Wetzlar, Germany) with a Planapo 1.0x objective. Images of select morphological features were produced using a Leica DFC 450 C Microsystems system (Leica, Wetzlar, Germany) with a Planapo 2.0x objective. Images were stacked using the Leica Application Suite V4.3 software or Zerene stacker V1.02 (Zerene Systems). Confocal images of genitalia were taken on a Leica SP5 Inverted confocal microscope at the Institute for Integrative Genome Biology core facility (http://genomics.ucr.edu/) using cuticular auto fluorescence excited by 488nm and 543nm lasers and collected by detectors in diapasons of 500–535nm (green in figures) and 555–700nm (red in figures). The resulting confocal images were rendered using Imaris V7.6.4 (Bitplane). Specimens used for Scanning Electron Microscopy were sputter coated with a platinum-paladium using a Cressington 108 auto sputter coater (Cressington, Watford, UK) before imaging using a FEI XL30-FEG Scanning Electron Microscope at the UCR Central Facility for Advanced Microscopy and Microanalysis (http://cfamm.ucr.edu/). All images were edited and assembled into image plates in Adobe Photoshop CS4.
To examine male genitalia, the abdomen was separated from the body and either cleared by placing into hot 10% KOH, or prepared for DNA extraction. For study of female genitalia the abdomen was separated from the body, cleared in KOH for ~10 minutes, and placed in Chlorazol Black E for three 30 second intervals. Line drawings were prepared using a Nikon Eclipse 80i compound microscope (Nikon, Tokio, Japan) with camera lucida.
Measurements (see Table
Species | Hypselosomops pecki | Hypsohapsis takiyae | ||||||
---|---|---|---|---|---|---|---|---|
Sex | Male (macropterous) | Male (brachypterous) | Female | 1st instar | 2nd instar | 4th instar | 5th instar | Male |
USI | UCR_ENT 00091116 | UCR_ENT 00091117 | UCR_ENT 00096912 | UCR_ENT 00096916 | UCR_ENT 00096917 | UCR_ENT 00096918 | UCR_ENT 00096919 | UCR_ENT 00111639 |
Total length | 1.49 | 1.03 | 1.09 | 1.51 | ||||
Body length | 1.53 | 1.03 | 1.38 | 0.69 | 0.80 | 1.03 | 1.13 | 1.48 |
Pronotum width | 0.61 | 0.53 | 0.54 | 0.74 | ||||
Pronotum length | 0.16 | 0.23 | 0.18 | 0.26 | ||||
Pronotal collar length | 0.04 | 0.07 | 0.05 | 0.05 | ||||
LC:LP | 0.23 | 0.28 | 0.28 | 0.21 | ||||
Vertex width | 0.36 | 0.36 | 0.37 | 0.28 | 0.22 | 0.31 | 0.33 | 0.50 |
Eye width | 0.68 | 0.65 | 0.67 | 0.41 | 0.46 | 0.60 | 0.61 | 0.92 |
Width between eyes | 0.37 | |||||||
Fore femora depth/ height | 0.07 | 0.08 | 0.08 | 0.05 | 0.05 | 0.07 | 0.07 | 0.17 |
Fore femora length | 0.28 | 0.30 | 0.28 | 0.17 | 0.13 | 0.24 | 0.25 | 0.56 |
DFF:LFF | 0.25 | 0.26 | 0.29 | 0.30 | 0.41 | 0.31 | 0.30 | 0.30 |
Hind tibia length | 0.61 | 0.59 | 0.56 | 0.24 | 0.24 | 0.30 | 0.42 | 0.72 |
LHT:WP | 1.00 | 1.11 | 1.03 | 0.97 | ||||
a1 length | 0.08 | |||||||
a2 length | 0.07 | |||||||
a3 length | 0.28 | |||||||
a4 length | 0.30 | |||||||
a3:a4 | 0.93 |
Unique specimen identifier (USI) labels consisting of a matrix-code and prefix plus eight-digit number were associated with each specimen. Specimen information was databased using the American Museum of Natural History’s Arthropod Easy Capture (AEC) Software database (http://www.research.amnh.org/pbi/locality/index.php). Specimens for which geographic coordinates were absent from the label were georeferenced using Google Earth. The associated information is available through the Heteroptera Species Pages (http://research.amnh.org/pbi/heteropteraspeciespage/) and the http://www.discoverlife.org/ website. Specimens stored in ethanol and voucher specimens for molecular study were also given an internal identification number. Maps were prepared in SimpleMappr (http://www.simplemappr.net/) using the coordinates exported from the AEC database.
This publication and the nomenclatural acts it contains have been registered in ZooBank, the online registration system for the ICZN. The ZooBank LSIDs can be resolved by appending them to the Web address http://zoobank.org/. The LSIDs for nomenclatural acts can be found in corresponding sections of this article.
We use the following abbreviations: 1An, first anal vein; 2An, second anal vein; ac, anal cell; ano, anophore; anop, anophoric process; ag, anterior gonapophysis; at, anal tube; bucc, buccula; ca, conjunctival appendage of vesica; cly, clypeus; clypD, clypeal depression; C, costa; cc, costal cell; Cu, cubitus; cub, cubital cell; dc, discal cell; DFF:LFF, ratio of height (termed depth in
Key to the genera of Hypselosomatinae in the Old and New Worlds (modified from
1 | First labial segment dorsally expanded, appearing lobelike in lateral view (Fig. |
2 |
– | First labial segment not dorsally expanded | 4 |
2 | Third and fourth labial segments not distinctly separated, with a sclerotized, hornlike or tubular structure occupying both segments (Fig. |
Williamsocoris Carpintero & Dellapé (NW) |
– | Third and fourth labial segments distinctly separated and without any ornamentation | 3 |
3 | Males with slightly enlarged first labial segment lacking anterior teethlike setae; clypeus of male lacking macrosetae and medially depressed with posterior flaplike expansion (Fig. |
Hypselosomops gen. n. (NW) |
– | First labial segment significantly enlarged, containing anterior teethlike setae (Fig. |
Ommatides Uhler (NW) |
4 | Clypeus without macrosetae | 5 |
– | Clypeus with 1–5 macrosetae; female never macropterous | 6 |
5 | Macropterous | major part of Rectilamina Hill (OW) |
– | Elytrous (Fig. |
Glyptocombus Heidemann (NW) |
6 | Clypeus with 1 macroseta | 7 |
– | Clypeus with 3–5 macrosetae | 8 |
7 | Vertex deflected 90° at posterior margin, with median furrow; venation normal width | Cryptomannus Hill (OW) |
– | Vertex not sharply deflected, without furrow; elytrous venation very wide | Lativena Hill (OW) |
8 | Clypeus with 5 macrosetae | 9 |
– | Clypeus with 3 macrosetae | 10 |
9 | Fore femur with long macrosetae | Hypselosoma Wygodzinsky (OW) |
– | Fore femur without macrosetae (Fig. |
Hypsohapsis gen. n. (NW) |
10 | Ratio of pronotal collar length to pronotum length ≥ 0.29 (elytrous), 0.25 (macropterous); Ratio of length of hind tibia to width of pronotum < 0.95 | 11 |
– | Ratio of pronotal collar length to pronotum length ≤ 0.25; ratio of length of hind tibia to width of pronotum > 0.95 | 12 |
11 | Body black | Pateena Hill (OW) |
– | Body brown | Macromannus Hill (OW) |
12 | Pronotal disc with transverse furrow; elytrous forewing cells with regular rows of large ovoid punctures | Ordirete Hill (OW) |
– | Disc with no furrow; cells not coarsely sculptured | 13 |
13 | First antennal segment with short macrosetae; second hind tarsomere with 2 short to medium macrosetae | major part of Duonota Hill (OW) |
– | First antennal segment without macrosetae; second hind tarsomere with 1 medium macrosetae (ignore long apical ventral seta) | 14 |
14 | Male genital capsule tapering to single curved process; proepisternum and pronotum black-brown to black | R. curvicauda Hill (OW) |
– | Capsule projecting at both posterior corners; proepisternum cinnamon, pronotum black with posterior angles cinnamon | D. bicamaca Hill (OW) |
– | Pronotal disc with 2 eye-like yellow spots, proepisternum brown; male unknown | D. bimaculata Hill (OW) |
Hypselosomops pecki sp. n.
Distinguished among Hypselosomatinae by males with two wing morphs (macropterous and submacropterous); slightly enlarged and dorsally expanded first labial segment lacking anterior “teeth-like” setae (Fig.
Male. Coloration. Head, thorax, abdomen ventrally, and forewing light to dark brown, with pale transverse band proximally on forewing; legs yellow, coxae brown; abdomen dorsally pale; genital capsule and genitalia light to dark brown. Surface and Vestiture. Clypeus without macrosetae, with a depression in apical half and a row of five small setae at apex; buccula and first labial segment each with a pair of stout ventrolateral macrosetae; second labial segment with pair of lateral macrosetae (Fig.
Hypselosomops: A male abdomen in dorsal view B male genitalia in dorsal view C male abdominal segments seven, eight, nine in ventral view D male tergite eight in lateral view E left side of female abdomen in lateral view F female abdomen in dorsal view G right side of female abdomen in lateral view H gonapophysis (pg- posterior gonapophysis, ag- anterior gonopophyses) I spermatheca including part of duct.
Hypselosomops male, SEM images: A frontal-lateral-dorsal view of head B hind tarsus C close-up of frontal mouthparts D frontal view of head E mid tarsus: F fore tarsus G ventral view of thorax with head, pronotum and left mid and hind legs removed (showing the peg-like structure between legs hypothesized to be used for jumping) H dorsal view of genitalia.
Female. Coloration. Similar to male. Surface and Vestiture. First antennal segment with five macrosetae; ratio of third antennal segment and fourth antennal segment approximately 0.93; clypeus not inflated with three (two basal, one at tip) macrosetae; second labial segment with pair of lateral macrosetae, buccula with pair of lateral macrosetae (Fig.
Nymphs: For habitus and size of first, second, fourth, and fifth instar nymphs, see Fig.
“Hypselosom” from Hypselosoma, the type genus of Hypselosomatinae, and “ops” which is Greek for “having the appearance of”, due to the similarity of this genus to Hypselosoma. The gender is feminine.
The medial apical indentation with small basal flap on the clypeus (Fig.
Specimens of this genus have been collected in Cuba and the Dominican Republic.
Type material.Holotype, male, slide mounted in Canada balsam: CUBA: Santiago, Gran Piedra, Isabelica, 20.08333°N 75.6°W, 1100 m, 07 Dec 1995 - 17 Dec 1995, S. B. Peck (UCR_ENT 00091116) (
As in generic diagnosis.
As in generic description.
See Table
Named in honor of Stewart B. Peck (Carleton University, Ottawa), who collected most known specimens of this species. A noun in genitive case.
Hypsohapsis takiyae sp. n.
Distinguished among Hypselosomatinae by first labial segment not dorsally expanded; clypeus with five macrosetae; 3 not 1 or 2 pairs of ventrolateral macroseta at base of mouthparts (bucculae and first two labial segments); fore femur without macrosetae; areolate fore wing with only traces of veins (Fig.
Male. Coloration. Head, thorax, and forewing brown (including eyes); legs yellow; basal portion of coxae brown, abdomen pale; genital capsule and genitalia brown. Surface and Vestiture. Clypeus with five macrosetae (two basal, three at tip); first labial segment with a pair of stout lateral macrosetae, second labial segment with pair of lateral macrosetae, buccula with pair of lateral macrosetae; fore femora without anterior macroseta; ratio of length of hind tibia to width of pronotum 0.97; hind tibia with five erect macrosetae ventrad on distal half. Structure. ratio of pronotal collar length to pronotum length 0.21; disc steeply declivous, not decurrent anteriorly (Fig.
Female. Unknown.
“Hypso” from Hypselosoma, the type genus of Hypselosomatinae, and “hapsis” which is Greek for “net” in reference to the netlike appearance of the fore wing due to their areolate and irregular, coarse sculpturing. The gender is feminine.
This currently monotypic genus is described from a single male specimen from southern Brazil. It is clearly set apart from all described genera of Hypselosomatinae by the unique and complicated structure of the male genitalia. In particular, the seemingly internal process of segment eight is unknown among described Dipsocoromorpha. Flap like processes of the genitalia occur in other Schizopteridae, but the origin of this process in Hypsohapsis is unclear. Unfortunately, dissection of the abdomen would be necessary for a detailed study of the above mentioned structures. Since only one specimen of the species was collected, we have limited our observations to studying the intact abdomen.
One specimen of this genus has been collected in Brazil.
Type material.Holotype, male, slide mounted in Canada balsam: BRAZIL: Sao Paulo: Ubatuba, Picinguata, -23.37743,-44.83733, 1997–2001, Nessimain, J.L. & Takiya, D.M. (UCR_ENT 00111639) (
As in generic diagnosis.
As in generic description.
See Table
Named in honor of Daniela Takiya who collected this specimen and loaned it to us. A noun in genitive case.
Based on our extensive specimen sorting efforts of Dipsocoromorpha with emphasis on Schizopteridae as part of the NSF-funded ARTS Litter Bug project, it has become clear that Hypselosomatinae are more widely distributed in the New World than previously documented and that a number of undescribed species remain to be described. The present contribution focuses on two new genus-level taxa, but descriptions of additional species are in progress and the analysis of molecular data will provide a phylogenetic framework for both New and Old World Hypselosomatinae (Hoey-Chamberlain and Weirauch, in prep.). The three previously described New World genera share a number of morphological characters. Ommatides and Williamsocoris both possess dorsally expanded first labial segments, while the male genitalia in Williamsocoris and Glyptocombus are very similar, both with a fingerlike process apically on sternite nine. The males of both Ommatides and Glyptocombus are submacropterous and elytrous. We have not been able to recover additional specimens of Ommatides insignis beyond the male holotype and certain details of the male genitalia therefore remain unknown. We were also unable to locate specimens that
In a series of taxonomic publications focusing on Hypselosomatinae,
Even though a diagnostic feature of Hypselosomatinae, the default number of four marginal cells can be modified, especially in micropterous and elytrous taxa. Four marginal cells are clearly visible in most macropterous taxa such as Williamsocoris and the male, macropterous form of Hypselosomops, but Glyptocombus, Ommatides, and Hypsohapsis have reticulate wings and/or reduced wing venation. Wing type in Hypselosomatinae can vary within species, but even within the same sex of the same species. Sexual dimorphism with respect to wing type occurs in taxa in both the Old (e.g., Rectilamina, Duonota, and Hypselosoma) and New Worlds (undescribed species of Williamsocoris and Glyptocombus; pers. obs.). Only Hypselosomops pecki and Pateena elimata Hill (
Ommatides insignis holotype: A enlarged first labial segment B anterior teeth like setae; Williamsocoris ornatus holotype: C enlarged first labial segment D horn like or tubular structure occupying third and fourth labial segments E anterior teeth like setae of first labial segment F pronotal collar G projection of genital capsule; and Glyptocombus saltator non-type: H projection of genital capsule
Although considered to be of value as a diagnostic feature at the genus level, comparative documentation of the spermatheca across Hypselosomatinae is rather incomplete. Females of Williamsocoris, Glyptocombus, Ommatides, and Hypsohapsis remain unknown and the spermatheca is assumed to be absent or poorly sclerotized in Hypselosoma (
The number of abdominal spiracles can vary dramatically between hypselosomatine genera, although variation can also occur within a genus.
Phylogenetic hypotheses are currently unavailable for Hypselosomatinae and our understanding of character evolution in the group is therefore limited to speculations. Hypsohapsis shares a number of morphological features with Macromannus and Ordirete including the three clypeal macrosetae, elytrous wings with reticulate/areolate pattern and the simple sternite nine with a rounded lobe. Hypselosomops in contrast more closely resembles Duonota and Rectilamina due to the lack of clypeal macrosetae on males and the three clypeal macrosetae on females, as well as, the modifications of tergite eight in males and the presence and shape of the spermatheca in females. Given some of the extraordinary morphologies of Hypselosomatinae, the worldwide distribution with small endemic species ranges, and the fossil record that dates back to more than 100 my (
We thank curators, collection managers, and research staff at various institutions for their help in facilitating specimen sorting and loans: James Boone, Rebekah Baquiran, and Margaret Thayer (