Metatibial Spur Research Articles

A new genus of halictine bees from Central America (Hymenoptera: Halictidae)

A new genus and species of halictine bees (Halictinae: Halictini: Mexalictina) is described and figured from a mid-elevation forest in northwestern Costa Rica. Meliamelitta vulcanus gen. and sp. n. is allied to Mexalictus Eickwort but differs in the structure of the labral basal elevation, the obtuse epistomal sulcus, the elongate mandibles, the pectinate inner metatibial spur, the unique pterostigma, and the sculpturing of the basal area of the propodeum, among other features. A key is appended to the genera and subgenera of Mesoamerican, Central American, and Caribbean Halictinae to facilitate the recognition of the genus.

Fine Morphological Study of the Myrmecina graminicola (Latreille, 1802) Male, With First Description of External Genitalia in the Genus (Hymenoptera: Formicidae: Myrmecinae)

The genus Myrmecina was described basing on males of M. graminicola. Though representing the caste type, males were sufficiently described in only two out of 105 species known in the genus. However, the morphology of the male external genitalia remained undescribed. Re‐examining by SEM the male of M. graminicola, we describe and illustrate in detail for the first time the external genitalia, redefining and updating the morphological male diagnosis of the genus. We also analyze the overall morphology, illustrating additional peculiar characters of this species as follows: (i) a very distinctive stipital groove in the dorsolateral stipes; (ii) a developed uncinate‐shaped mesoscutellar arm; (iii) the antennal cleaning; and (iv) the absence of meso‐ and metatibial spurs. This morphological study will be useful as a base for further morphological descriptions of the males in other species of the same genus to support correct taxonomic identifications.

A Fine Morphological Study of the Rare Anillidris bruchi Santschi (Hymenoptera: Formicidae: Dolichoderinae) Male and Queen.

Using optical and scanning electron microscopy, we describe the following new morphologically distinctive characters of the rare Neotropical ant Anillidris bruchi Santschi, 1936, male and queen: scattered setae inter-ommatidia, semicircular hypostomal notch, antennal cleaning, metatibial spurs, and the remnant of the M2 vein in the hindwings. In males, we show for the first time the morphology of maxillary and labial palpi, the absence of metapleural glands, and, in external genitalia, for the first time in ants, a new mechano-sensory area on the volsella that we called "volsella sensorium", composed of several spine-like sensilla. Additionally, we give an updated morphological diagnosis of the alate caste, which will be useful for future studies to clarify the phylogeny of the genus Anillidris.

Two new genera of the Elcanidae (order: Orthoptera) from middle Cretaceous Burmese amber of northern Myanmar

Hukawnelca gracile gen. et sp. nov. and Caelielca spinocrus gen. et sp. nov. (Orthoptera: Elcanidae) from middle Cretaceous Burmese amber are characterized by morphological characteristics of the pronotum, metatibial spurs, and wing venation. The Hukawnelca gracile gen. et sp. nov. had the unique anatomical characters such as a long dorsal margin of the pronotum, large broad leaf-like metatibial spurs, several spines on the metatarsus, and forewing venations. Caelielca spinocrus gen. et sp. nov. had the unique morphologies of non-prolonged head and wing venation similar to those in Caelifera species. These unique morphologies of both species distinguished them from the earlier Elcanid species.

First record of Leptoomus janzeni Gibson (Hymenoptera, Chalcidoidea) from Rovno amber

The large and distinctive chalcidoid wasp Leptoomus janzeni Gibson, 2008, originally described from late Eocene Baltic amber, is newly recorded from coeval Rovno amber (Ukraine) based on a single well-preserved female specimen. Only 66 species of Rovno hymenopterans (49%) are also known from Baltic amber. High resolution photomicrographs and measurements of the specimen are given. Some character states of the new specimen, such as a green metallic coloration, a bare and flat prepectus, location and number of multiporous plate sensillae on the flagellum, sclerotized spur vein of the hind wing, and two metatibial spur are reported in this species for the first time.

A diminutive elcanid from mid-Cretaceous Burmese amber, Ellca nevelka gen. et sp. nov., and the function of metatibial spurs in Elcanidae (Orthoptera)

Ellca nevelka gen. et sp. nov. (Orthoptera: Elcanidae) is described from mid-Cretaceous Burmese amber and it is the smallest known elcanid (body length = 4.53 mm) characterized by a combination of morphological characters on the head, pronotum, metatibial spurs, and metatarsomeres. Well-preserved forewing venation indicates that the fossil belongs to Elcaninae; as such, this species is the latest known representative of this subfamily. The described species has a narrow pterostigma on its forewings, which suggests that this species could use both pairs of wings for active flight. A new hypothesis is proposed for the function of the enlarged and flattened metatibial spurs, which could help stabilize and control flight.

Molecular Phylogeny and Infraordinal Classification of Zoraptera (Insecta).

Zoraptera is a small and predominantly tropical insect order with an unresolved higher classification due to the extremely uniform external body morphology. We, therefore, conducted a multigene molecular phylogeny of extant Zoraptera and critically re-evaluated their morphological characters in order to propose a natural infraordinal classification. We recovered a highly-resolved phylogeny with two main clades representing major evolutionary lineages in Zoraptera, for which we propose family ranks. The two families exhibit striking differences in male genitalia and reproductive strategies. Each family contains two subclades (subfamilies) supported by several morphological synapomorphies including the relative lengths of the basal antennomeres, the number and position of metatibial spurs, and the structure of male genitalia. The newly proposed higher classification of Zoraptera includes the family Zorotypidae stat. revid. with Zorotypinae Silvestri, 1913 (Zorotypus stat. revid., Usazoros Kukalova-Peck and Peck, 1993 stat. restit.) and Spermozorinae subfam. nov. (Spermozoros gen. nov.), and Spriralizoridae fam. nov. with Spiralizorinae subfam. nov. (Spiralizoros gen. nov., Scapulizoros gen. nov., Cordezoros gen. nov., Centrozoros Kukalova-Peck and Peck, 1993, stat. restit., Brazilozoros Kukalova-Peck and Peck, 1993, stat. restit.), and Latinozorinae subfam. nov. (Latinozoros Kukalova-Peck and Peck, 1993, stat. restit.). An identification key and morphological diagnoses for all supraspecific taxa are provided.

Case of mistaken identity: resolving the taxonomy between Trioza eugeniae Froggatt and T. adventicia Tuthill (Psylloidea: Triozidae).

The 'Eugenia psyllid' or 'Lilly pilly psyllid', widely recognized in Australia and in the USA as Trioza eugeniae Froggatt (Hemiptera: Triozidae), is not T. eugeniae, but rather T. adventicia Tuthill. In this study we assessed morphological comparisons of materials from throughout the native and introduced ranges and re-examined original descriptions of both taxa, together with Froggatt's type specimens of T. eugeniae. Furthermore, through DNA barcoding analyses, we confirmed the validity of both T. adventicia and T. eugeniae as separate species. We re-described both species to include additional characters not previously included and designated a lectotype for T. eugeniae. T. eugeniae has smaller fore wings that are slightly more elongate. These lack infuscation around veins R and R1, vein Rs is relatively longer, meeting the costa closer to the wing apex; with certain veins bearing long, fine divergent setae, a character not previously described. It has consistently three inner and one outer metatibial spurs. The male parameres appear narrowly pyriform with a weak dorsolateral lobe and weakly sclerotized apices. T. adventicia has larger fore wings that are slightly more ovate with dark infuscation around veins R and R1; vein Rs is relatively shorter, meeting the costa further from the wing apex, with veins lacking long, fine divergent setae. The usual configuration of two inner and one outer metatibial spurs, previously used to separate the two species, appears inconsistent. The male parameres appear a little more broadly pyriform with slightly more sclerotized apices. T. eugeniae refers to a distinct species which has a restricted distribution only in its native range in southern subcoastal New South Wales, Australia. T. adventicia refers to a separate species, with a natural distribution in eastern subcoastal Australia, but has been introduced widely in southern Australia, to New Zealand and the USA. This study elucidates a long history of misidentification of T. eugeniae in the nursery industry and in almost 30 years of literature on its biological control in the USA. Regardless, the biological control program, unknowingly, targeted the correct species of psyllid, T. adventicia, in its foreign exploration and importation of the appropriate parasitoid as a biocontrol agent in the USA. Despite being firmly entrenched in both the nursery trade and scientific literature, the name T. eugeniae is misapplied. While the acceptance of the valid name, T. adventicia, might be regarded as both problematic and protracted, this is the correct taxonomical attribution.

The first Ripipterygidae (Orthoptera: Caelifera: Tridactyloidea) from mid-Cretaceous Burmese amber

The first mud cricket, Archaicaripipteryx rotunda gen. et sp. nov., is described based on a well-preserved specimen from mid-Cretaceous Burmese amber. It can be definitely assigned to Ripipterygidae based on its uninflated mesotibiae, unsegmented cerci and each ventral valve with a powerful side tooth. However, the morphology of this new mud cricket shows distinguishing characteristics including interocular distance at least the width of the compound eyes, metatarsus at least twice the length of the metatibial spurs, and distinctive subapical denticular process on the metatarsus, providing novel morphological diversity of the Ripipterygidae. Archaicaripipteryx rotunda gen. et sp. nov. is not only the first record of the Ripipterygidae from mid-Cretaceous Burmese amber, but also the oldest fossil record of Ripipterygidae, extending the geological range of this family by approximately 80 million years.

A new singular species of Croscherichia Pardo Alcaide, 1950 (Coleoptera, Meloidae, Mylabrini) from arid zones of eastern Morocco.

A new species of blister beetle (Coleoptera, Meloidae, Mylabrini), Croscherichia armass Ruiz, François & García-París, sp. nov., is described from the arid steppes of eastern Morocco (Missour, Boulemane Province). The new species presents traits shared with both Croscherichia and desert species of the genus Ammabris, making it morphologically singular. Conspicuous external similarities (coloration pattern, shape of the mandibles, setation) between C. armasssp. nov. and Ammabris allow the two to be easily confused. However, C. armasssp. nov. can be readily distinguished from all other Croscherichia species by the following traits: reddish-orange legs with dark tarsi; relatively short black antennae with the proximal-most three to four antennomeres of each antenna having a reddish-brown coloration; dense and silvery body setation that lies over most of the body integument; straight and pointed outer mandible margins that protrude from the labrum; a mesosternum with an angulate anterior margin; a short, subcylindrical, and weakly spatulate external metatibial spur that is truncated obliquely at the apex. Croscherichia armasssp. nov. is only known from three localities in the arid Hammada steppes, which are located within the Quaternary alluvial plains of the Muluya river valley. Live specimens of C. armasssp. nov. were found in flight and actively feeding on Atriplex halimus (Chenopodiaceae) flowers at the end of summer (mid-September). The phenology of C. armasssp. nov. is exceptional as no other Mylabrini species known from eastern areas of Morocco are active in late summer.

New species of Xiphoscelis Burmeister, 1842 (Coleoptera, Scarabaeidae, Cetoniinae) from arid regions of South Africa and Namibia.

Two new species of the southern African genus Xiphoscelis Burmeister, 1842 are recognised and described, X. braunsisp. nov. from the Eastern and Western Cape Karoo (South Africa) and X. namibicasp. nov. from the Huns Mountains of southern Namibia and adjacent ranges in South Africa. These were previously overlooked and grouped together with X. schuckardi Burmeister, 1842, but further material and more in-depth analyses have now revealed their clear separation on the basis of key diagnostic features, including clypeal structure, metatibial spur development and aedeagal shape. The densely and coarsely costate elytral structure and the black to brown colour of these species are symplesiomorphies shared with a number of the most primitive genera among the African Cetoniinae. However, these characters also reflect the convergent adaptation to hot and arid conditions they share with several other species occurring in this region. Phylogenetic relationships of the genus with other Cetoniinae are explored using the larval characters highlighted in the description of the 3rd instar larva of X. braunsisp. nov. The extraordinary hypertrophy observed in the male metatibial spur of species in this genus, and particularly in X. schuckardi, appears to represent a defence mechanism against potential predators on the ground, apart from playing a role during mating.

A new genus of augochlorine bees from northern Venezuela (Hymenoptera: Halictidae)

A new genus and species of the bee tribe Augochlorini (Halictinae) is described and figured from northern Venezuela. Trichommation osculans Engel, new genus and species, is a member of the Megaloptidia-group of genera as evidenced by the narrow and elongate mouthparts and sharply pointed galeal apex. The genus is most similar to Megommation Moure and Megaloptidia Cockerell, particularly in the enlarged ocelli present only in these genera among those in the group. Aside from intermingling traits of both of these genera, Trichommation is further distinct from both owing to the presence of ocular setae, a pectinate inner metatibial spur, and basal rugae on the basal area of the propodeum. Emendations to the key to genera of the Megaloptidia group are provided to allow for the identification of Trichommation.

A new species of Ctenaugochlora from northwestern Ecuador (Hymenoptera: Halictidae)

The bee subgenus Ctenaugochlora Eickwort (Halictinae: Augochlorini) is recorded from Ecuador for the first time, and a new species is described and figured. Caenaugochlora (Ctenaugochlora) isaaci sp. n., represents the first confident record of its subgenus in South America and can be distinguished from its closest relatives on the basis of head shape, integumental sculpture, inner metatibial spur morphology, propodeal lamellae, and general coloration. A revised key to the species of Ctenaugochlora is provided.

A new subfamily of hide beetles from the Cretaceous of northern Myanmar (Coleoptera: Scarabaeoidea: Trogidae)

ABSTRACT With four genera and some 330 extant species, the Trogidae are a small group of scarabaeoid beetles that feed on hard keratinous tissue. Here, the first hide beetle from mid-Cretaceous Burmese amber, Kresnikus beynoni gen. et sp. nov., is described and illustrated, representing the first trogid preserved in fossilised resin. A new subfamily, Kresnikinae subfam. nov., is erected for the unusual species, characterised by frons and clypeus completely fused, a deflexed anteromedial portion of the frontoclypeal region, clypeus with a straight anterior margin, subtriangular scutellum, pronotum and elytra with simple setae, mesocoxal cavities separated by a rounded metaventrite process, metatibial spurs as long as the first metatarsal segment, and metatarsi sparsely pubescent. Kresnikus beynoni gen. et sp. nov. shows several seemingly ancestral characters including separated mesocoxae and small body size, hinting at a Gondwanian origin of hide beetles. The fossil record of the family Trogidae is reviewed and an annotated checklist of fossil taxa is provided.

A new species of Elcaninae (Orthoptera, Elcanidae) from the Lower Cretaceous Yixian Formation at Liutiaogou, Inner Mongolia, NE China, and its morphological implications

Two adult females of Elcanidae (Orthoptera: Elcanoidea) from the Lower Cretaceous Yixian Formation of China are described as a new species, Probaisselcana euryptera sp. nov. The new materials have both wings and body structures well preserved. The new species differs from all other Elcaninae species in forewing venation and body features. The new specimens provide more morphological information of body structures of elcanids. The function of their flattened metatibial spurs is discussed.

The first Archelcaninae (Orthoptera, Elcanidae) from the Cretaceous Jehol Biota of Liaoning, China

A new genus and species of Elcanidae (Orthoptera: Elcanoidea) is described from the Yixian Formation of northeastern China. Jeholelcana yanensis gen. et sp. nov., represents the first Archelcaninae to be formally described from the Mesozoic of China. The new genus with both forewing and hind tibiae well preserved differs from all other Archelcaninae in aspects of forewing venation and morphology of the metatibial spurs. The new specimen provides new information on the characteristics of the family Elcanidae. The new species, with both forewing and metaleg preserved, sheds light on the venation of elcanids with leaf-like metatibial spurs, previously known only from nymphs. The types of metatibial spurs of the family Elcanidae are discussed.

A new tribe of Galerucinae leaf beetle (Insecta: Coleoptera: Chrysomelidae) from the Upper Cretaceous Taimyr amber

The new tribe Taimyralticini trib. nov., new genus Taimyraltica gen. nov. and new species Taimyraltica calcarata sp. nov. (Coleoptera: Chrysomelidae: Galerucinae) are described from Upper Cretaceous (Santonian) Taimyr amber of northern Siberia (Yantardakh locality). The new genus shares characters with genera of the tribe Alticini (small size, transverse antebasal groove on pronotum, regular punctate-striate elytra) and the Galerucini (narrow, non-swollen metafemora). A possible apomorphy of the new genus and tribe is a large and acute metatibial spur, erect and oriented transversely to the longitudinal axis of tibia. This character state is unknown in recent and fossil genera of Galerucinae. Early evolution and divergence of leaf beetles are discussed, and a Jurassic and Early Cretaceous subfamily radiation is proposed. Fossil galerucines are reviewed. The oldest Phyllotreta is recorded from the lower Miocene of Izarra (Spain). Our findings show an extreme rarity of Phytophaga in Taimyr amber from Yantardakh. Absence of Phytophaga was recorded earlier at Obeschayuschiy (Santonian-Campanian of the Magadan Region) and compared with their much larger share in Khetana (north of Khabarovsk Krai); we find nearly the same differences between Taimyr amber from Yantardakh and Canadian amber. In Obeschayuschiy this appears due to the Mesophytic character of the flora. It is assumed that the Santonian amber gymnosperm forest of the Khatanga Basin had the same character.

A new species of Samba s. str. (Hymenoptera: Melittidae) from the Turkana Basin, Kenya with observations on the function of the metatibial spur in females.

The third known species of the Afrotropical subgenus Samba s. str. is described based upon eight females. This is the northernmost and also the most arid habitat record for the genus. Images are provided of the habitus and diagnostic features for the species as well as the subgenus and some notes on floral hosts and habitat are provided. The species is added to a morphology-based phylogeny for the genus and results of barcoding of some species of the genus are presented. Some unusual morphological features of the subgenus are discussed, in particular, the function of the remarkable metatibial spurs of the female is recorded as assisting with removal of pollen from a floral host.

НОВАЯ ТРИБА ХРУЩЕЙ ИЗ ВЬЕТНАМА (COLEOPTERA, SCARABAEIDAE, MELOLONTHINAE)

A new genus and two new species of Melolonthinae are described from Dalat Highlands of Vietnam at altitude 750-800 m. Together with the monotypic genus Pseudoisonychus Frey, 1971 it is separated in the new tribe Langbianellini. Diagnoses of the new taxa: Langbianellini trib. n.: Labrum horizontal, on the same plane with clypeus to forming labroclypeus; maxillae with a long pubescence reminiscent a “sucking brush” of Valgines; antennae 8- or 10-articulated, with small 3-jointed club; anterior margin of pronotum with membranous border; propygidium strongly enlarged and inflated, fused with 5th sternite; pygidium reduced; metacoxae narrow, legs gracile; metatibial spurs closely spaced, attached below metatarsus; claws symmetrical. Langbianella g. n.: Antennae 8-joined, 3rd joint of club somewhat reduced in size, with a slit-like stripe of microsensillae; anterior margin of labrum concave; pronotum broadest at base; elytrae with 10 striae, all reaching to apex; body with a specialized setosity; all claws splitting. L. auricomes sp. n.: simple punctures between the setigerous punctures of pronotum very fine and sparse, umbilicate punctures lacking setae present at the lateral thirds of the pronotal base only; punctate rows of elytra with simple hairs; basal two-thirds and apical part of the 1st elytral interspace with patches of very long bright erect hairs in several rows; elytrae, pygidium and propygidium without microsculpture; pygidium uniformly covered with setigerous punctures; scutellum with sparse and irregular small punctures; middle third of 5th abdominal sternite uniformly covered with umbilicate setigerous punctures; abdomen reddishbrown. L. pterolepis sp. n.: simple punctures between the setigerous punctures of pronotum dense and rough, umbilicate punctures lacking setae present at the posterior part of the pronotal disc and along the pronotal base; punctate rows of elytra together with an additional punctate row in each of the odd interspaces bearing the modified dorsally expanded setae; elytrae, pygidium and propygidium with rough shagreen-like microsculpture; pygidium with bald medial stripe; scutellum with sharp and confluent puncturation; middle third of 5th abdominal sternite with a single row of umbilicate setigerous punctures near its distal edge; abdomen black.

A new species of <i>Ptiloglossa</i> from Mexico, with new records of <i>Ptiloglossa cyaniventris</i> from Panama and Costa Rica (Hymenoptera: Colletidae)

A new bee species of the genus Ptiloglossa Smith (Colletidae: Diphaglossinae: Caupolicanini) is described and figured from Jalisco, Mexico, while new records are provided for Ptiloglossa cyaniventris Friese from Panama and a single locality in Costa Rica. Ptiloglossa chamelensis Ayala & Engel, new species, is endemic to Mexico and is close to P. rugata Moure, both sharing a similar shape in the fused metatibial spur, but in the new species the metatibia is widest at the level of the spur, and the female has black integument with dense yellow pubescence on metasomal terga I–IV. Ptiloglossa cyaniventris is newly recorded from males collected in Panama and Costa Rica and is characteristic for its dark integument, with intense metallic blue highlights on the metasomal terga, the narrow and long metatibia, and elongate metabasitarsus with an anterior, longitudinal ridge and slightly depressed outer surface.