Baozhen Hua

Morphology of immature stages of Bittacus choui (Mecoptera: Bittacidae) with notes on its biology

The hangingfly Bittacus choui Hua et Tan, 2007 is unique in Bittacidae for having only three instead of four larval instars. Its morphology was studied and illustrated in detail for developmental stages, including egg, larva and pupa. Ultrastructure of eggs, larval head, spiracles and prolegs are provided. The egg is spherical. A single micropyle was observed. The larva is eruciform with a pair of prominent compound eyes and a mid ocellus; the eight pairs of prolegs are unequal in length. Nine pairs of spiracles are located on the prothorax and the first eight abdominal segments respectively; the first instar larva differs from other instars in spiracle number. The somites are unusual, with rows of protuberances bearing distinct setiferous clavate setae. The anal segment terminates in a protrusile sucker. Pupae are exarate and decticous, taking the shape of the adults. The species completes one generation per year, overwintering as a mature larva. Adults emerge in the field from mid‐July to late August.

A new species of the genus Panorpa (Mecoptera: Panorpidae) from China with notes on its biology

A new species of the scorpionfly, Panorpa longihypovalva sp. nov., is described and illustrated from the Qinling‐Bashan Mountains, the dividing line between the Palearctic and the Oriental Regions in central China. The immature stages, including egg and larva, were obtained through rearing. Its biology and behaviour are briefly reported and illustrated.

Female genital plate diversity and phylogenetic analyses of East Asian Panorpidae (Mecoptera)

Male genitalia have been widely used in taxonomy and phylogenetic analysis in most groups of insects. However, except in a few groups, taxonomists have widely overlooked or neglected the significance of female genitalia for phylogenetic analysis. The female genital plates of 26 species in four genera of East Asian Panorpidae (Mecoptera) were investigated using light and scanning electronic microscopy. The phylogeny of these species was analysed with maximum parsimony based on characters derived from the female genital plates, in combination with other characters, employing Brachypanorpa carolinensis and Panorpodes kuandianensis (Panorpodidae) as outgroups. The results show that the female genital plate of the Panorpidae is a reliable character both for species delimitation and phylogenetic analysis. The monophyly of the genus Sinopanorpa is well supported in the topology. The genus Panorpa is reconfirmed to be paraphyletic and probably deserves subdivision. Notably, the P. amurensis, P. centralis (= P. cornigera group), and P. diceras groups are evidently monophyletic and might merit generic or subgeneric status. However, the P. davidi group is definitely paraphyletic and needs further systematic study. The origins and evolutionary pathway of the female genital plate of the Panorpidae are briefly discussed.

Ultrastructure of the sensilla on larval antennae and mouthparts in the peach fruit moth, Carposina sasakii Matsumura (Lepidoptera: Carposinidae)

The ultrastructure of the sensilla on the larval antennae and mouthparts of the peach fruit moth, Carposina sasakii Matsumura, were investigated using scanning electron microscopy. On each three-segmented antenna, the basal scape is devoid of sensilla, the pedicel possesses two sensilla chaetica and three sensilla basiconica, and the terminal flagellum carries distally one sensillum styloconicum and three sensilla basiconica. The labrum bears six pairs of sensilla chaetica; the epipharynx carries two pairs of small epipharyngeal sensilla, three pairs of flattened sensilla chaetica, and a pair of broad sensillum digitiformium. Each dentate mandible carries two sensilla chaetica basally on its outer face. On the maxillae, the cardo and stipes each carry a sensillum chaeticum distally; each galea has three elongate flattened sensilla basiconica, two short sensilla chaetica, and two large sensilla styloconica. The distal segment of the maxillary palp possesses distally seven sensilla basiconica and one sensillum styloconicum, and laterally one sensillum digitiformium and one sensillum placodeum. Each labial palp bears distally a short cone-shaped sensillum chaeticum and an elongate slender sensillum styloconicum. The possible functions of these sensilla in the feeding process are briefly discussed.

Dicerapanorpa, a new genus of East Asian Panorpidae (Insecta: Mecoptera: Penorpidae) with descriptions of two new species

Dicerapanorpa gen. nov. is erected with Panorpa magna Chou as its type species. The genus is recognizable by the following characters: body yellowish with two blackish lateral longitudinal stripes on dorsum; tergum VI of males with two anal horns; abdominal segment VII of males much thinner at the basal half and abruptly thicker at apical half; parameres of males trifurcate; female genital plate with the axis not extending beyond the main plate. Six new combinations, Dicerapanorpa magna (Chou in Chou et al., 1981), D. diceras (MacLachlan, 1894), D. stotzneri (Esben-Petersen, 1934), D. tjederi (Carpenter, 1938), D. kimminsi (Carpenter, 1948) and D. triclada (Qian and Zhou, 2001) are transferred from Panorpa Linnaeus. Dicerapanorpa baiyunshana sp. nov. and Dicerapanorpa shennongensis sp. nov. are described and illustrated. A key to the genera of Panorpidae is updated to include the new genus. A key to the species of Dicerapanorpa gen. nov. is also presented. http://www.zoobank.org/urn:lsid:zoobank.org:pub:F50E44C3-7275-4EC8-B048-4C7B2C6D57EF

Embryonic development of the scorpionfly Panorpa emarginata Cheng with special reference to external morphology (Mecoptera: Panorpidae)

The Mecoptera are thought to be one of the most primitive groups in the Holometabola, but their embryology is rarely studied. By means of scanning electron microscopy, we studied the external features of the embryo of the scorpionfly Panorpa emarginata in middle and late development. The embryo remains in the superficial position until hatching. Embryonic development can be divided into 10 stages along with the first‐instar larva. The external features are described from the germ band to the first‐instar larva, with special reference to the components and segmentation of the head, the segmentation of abdomen and the formation of abdominal prolegs. Our results confirm that the head consists of an anterior‐most acron and six trunk segments: the labral, antennal, intercalary, mandibular, maxillary, and labial segments. The labrum is confirmed to derive from the paired appendages. Our observations also provide additional direct evidence that the abdominal prolegs are not serially homologous with the thoracic legs. The presence of the eleventh abdominal segment is clarified. J. Morphol. 2009.

Ultrastructure of the larval eye of the scorpionfly Panorpa dubia (Mecoptera: Panorpidae) with implications for the evolutionary origin of holometabolous larvae

The evolutionary origin of holometabolous larvae is a long‐standing and controversial issue. The Mecoptera are unique in Holometabola for their larvae possessing a pair of compound eyes instead of stemmata. The ultrastructure of the larval eyes of the scorpionfly Panorpa dubia Chou and Wang, 1981 was investigated using transmission electron microscopy. Each ommatidium possesses a cornea, a tetrapartite eucone crystalline cone, eight retinula cells, two primary pigment cells, and an undetermined number of secondary pigment cells. The rhabdomeres of the eight retinula cells form a centrally‐fused, tiered rhabdom of four distal and four proximal retinula cells. The rhabdomeres of the four distal retinula cells extend distally into a funnel shape around the basal surface of the crystalline cone. Based on the similarity of the larval eyes of Panorpidae to the eyes of the hemimetabolous insects and the difference from the stemmata of the holometabolous larvae, the evolutionary origin of the holometabolous larvae is briefly discussed. Morphol., 2012.

Comparative morphology of the eggs in some Panorpidae (Mecoptera) and their systematic implication

Abstract The egg ultrastructure of 12 species in three genera of Panorpidae: Panorpa Linnaeus, Neopanorpa Weele and Sinopanorpa Cai & Hua, was examined using scanning electron microscopy. This is the first time the egg characters have been studied in detail for this family. The results show that egg morphology can be utilised for panorpid taxonomy both at the generic and specific levels. In the species investigated, the egg chorion is covered with a network of extrachorion. Several micropyles were visible on the anterior pole of the eggs after the extrachorion was removed. Neopanorpa eggs differ from the other two genera by neighbouring ridges of exochorion, which are separate and independent. The eggs of Sinopanorpa and Panorpa have only one fused ridge between every two adjoining polygonal cells. The eggs of Sinopanorpa have a network of ridges with even top edges, the granules within the cells being small and uniform. However, the eggs in the nine species of Panorpa are very diverse in morphology, reaffirming the heterogeneity and paraphyly of Panorpa, which may need further systematic analyses.

Ultrastructural comparison of the ocelli of Sinopanorpa tincta and Bittacus planus (Mecoptera)

On the contrary to compound eyes, dorsal ocelli are poorly investigated for their ultrastructure in many insect groups, including Mecoptera. The ocellar ultrastructure of the scorpionfly Sinopanorpa tincta (Navás) in Panorpidae and the hangingfly Bittacus planus (Cheng) in Bittacidae was examined using transmission electron microscope. Both species possess three ocelli on the vertex of their heads and each ocellus has a corneal lens, some pigment cells at the outer rim of the lens, and fused rhabdoms. Beneath the corneal lens lies a single layer of corneagenous cells, which is very thick with the nuclei located proximally in S. tincta and quite thin in B. planus. A portion of rhabdom is composed of rhabdomeres from two adjacent retinula cells in S. tincta, but from four retinula cells in B. planus. Each rhabdomere comprises parallel microvilli projecting laterally from the apposed retinula cells. In addition, abundant electron‐lucent granules are present at the middle part around each retinula in B. planus. Only pigment granules exist around the retinula proximally at the nucleate level in S. tincta. Microsc. Res. Tech., 2010.

Ultrastructure of the seminal vesicle and sperm storage in Panorpidae (Insecta: Mecoptera)

The histology and ultrastructure of the seminal vesicle, male accessory gland and the epididymis in Panorpa and Sinopanorpa were observed using light microscopy and scanning and transmission electron microscopy. The seminal vesicle consists of a mono-layered elongated columnar epithelium, which contains abundant electron-dense granules and secretory vesicles, and a small central lumen. In the apical region of the epithelium of the seminal vesicle, the intense secretory activity seems to be effected by means of merocrine mechanisms. The epithelium of the accessory gland is rich in rough endoplasmic reticulum and Golgi complex, and secretes seminal fluid into the lumen via both apocrine and merocrine mechanisms. The seminal vesicle is similar to the accessory gland in the epithelium structure and their secretory activity, mainly serving a secretory function rather than storing sperms. Instead, the sperms are stored in the epididymis, whose epithelium secretes nutrients into the large lumen by merocrine mechanisms. The secretory activity and function of the seminal vesicle are briefly discussed.