Corresponding authors: Gexia Qiao (
Academic editor: J. Zahniser
Luo X, Cai W, Qiao G (2017) Half-jumping plant lice – a taxonomic revision of the distinctive psyllid genus
Based on a synthesis of fossil studies, the defining character of
A new species,
This study is based on the collections of the
Slides were prepared following this protocol: whole insect soaked in boiling potassium hydroxide (
Measurements were taken with a Keyence VHX-1000 digital microscope using the measuring function and are given in millimeters (mm). For adults:
For fifth instar immatures:
Total body length of adults was not determined because most dry-mounted specimens examined were in distinct positions and therefore incomparable.
Comparisons of morphological characters were based on direct observations of specimens, drawings,
Terminology primarily follows
Scientific names of plants follow the
Body relatively flat. Vertex, thoracic dorsum and most of fore wing veins with symmetrical long and thick setae, which possess tiny spinules on the surface (Fig.
Head slightly inclined from longitudinal body axis. Vertex lacking median suture; two tubercles present along the median line, each bearing a pair of prickly setae. Base of lateral ocelli moderately bulging, each bearing two prickly setae. Vertex consistent with gena. Plane of torulus about perpendicular to that of the vertex. Frons completely fused with vertex and gena, only moderately raised from the surface. Gena not divided into two lateral parts, but firmly compact as one, with roughly symmetrical simple setae (Fig.
Preepimeron significantly wider than preepisternum. Notopleural sulcus of prothorax well developed. Mesopraescutum near semicircular, not protruding forward to force pronotum to arch. Pleural sulcus of mesothorax reduced, with pleural apophysis relatively small; posterior margin of mesopleurite directed forward. Mesepisternum rather narrow and bulging (Fig.
Legs long and slender. The three sensory pores on femora ventrum arranged in a row. Plane of hind legs almost parallel with that of middle legs. Metacoxa with rather large tubercle above apical opening, and lacking meracanthus (Fig.
Fore wing narrowest in the base and gradually becoming much wider apically, usually widest at subapex or apical 1/4. Costal break present. Pterostigma absent. Vein Rs reaching anterior margin instead of apical margin. Cell cu1 rather long and flat. Veins A1 and A2 touching in the middle. Anal break adjacent to the apex of vein Cu1b.
Hind wing with partially thickened anterior margin. Veins A1 and A2 combined or one is lost (probably A1), leaving a thickened vein A; cell a1 lost (Fig.
Tergite of abdominal segment 1 better developed, with a median sclerite present (Fig.
Male terminalia: In natural status, proctiger, aedeagus and parameres all oriented caudally instead of upwards. Posterior aspect of proctiger enveloped. Aedeagus uni-segmented and simple, sometimes with tiny spines on dorsum. Sperm pump with only basal end plate, lacking apical end plate (Fig.
Female terminalia: Subgenital plate placed much more proximal than proctiger and simple, lacking tip sometimes. Proctiger lacking rows of long setae on the dorsum. Valvula dorsalis of ovipositor without flag lobe. Median valve slender and placed more terminal, apex touching the subapex of ovipositor.
1 | Mesoscutum with 5+5 prickly setae (Fig. |
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– | Mesoscutum with 4+4 prickly setae (Fig. |
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2 | Fore wing colorless, with one prickly seta on the base of vein M3+4 (Fig. |
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– | Fore wing with black sections on veins, without prickly setae on vein M3+4 (Fig. |
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3 | Fore wing with yellow bands, with rather long prickly setae on veins but M3+4 (Fig. |
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– | Fore wing without color patterns, with relatively short prickly setae on veins including M3+4 (Fig. |
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1 | Body dorsum with acute-tipped sectasetae (Figs |
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– | Body dorsum with truncate sectasetae. Circum anal ring simple, both outer and inner rings composed of single row of pores. |
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2 | Outer margin of head and fore wing pad with closely packed sectasetae (Fig. |
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– | Outer margin of head and fore wing pad with fewer and scattered sectasetae (Figs |
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Vein M3+4 of fore wing with 3 prickly setae (Fig.
Structures: Setae on dorsum of body relatively long (Table
Measurements in mm.
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4♂♂ | 0.34–0.36 | 0.36–0.47 | 0.65–0.92 | 0.32–0.35 | 1.00–1.08 | 0.40–0.45 | ||
2♀♀ | 0.36–0.38 | 0.40–0.48 | 1.04–1.06 | 0.38–0.39 | 1.23–1.24 | 0.46–0.48 | |||
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4♂♂ | 0.42–0.44 | 0.71–0.76 | 0.80–0.88 | 0.49–0.50 | 1.84–1.92 | 0.70–0.72 | ||
4♀♀ | 0.44–0.46 | 0.65–0.73 | 0.83–0.95 | 0.52–0.56 | 2.10–2.23 | 0.59–0.67 | |||
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4♂♂ | 0.36–0.38 | 0.87–0.92 | 1.37–1.54 | 0.36–0.38 | 1.38–1.41 | 0.56–0.59 | ||
3♀♀ | 0.39–0.41 | 0.92–0.96 | 1.47–1.58 | 0.42–0.44 | 1.53–1.62 | 0.67–0.69 | |||
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4♂♂ | 0.42–0.43 | 0.77–0.80 | 0.74–0.81 | 0.40–0.48 | 1.80–2.01 | 0.64–0.72 | ||
4♀♀ | 0.42–0.44 | 0.71–0.85 | 0.83–0.88 | 0.45–0.48 | 1.98–2.20 | 0.60–0.64 | |||
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n = 5 | 0.89–0.99 | 0.34–0.38 | 0.29–0.33 | 0.30–0.35 | ||||
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n = 2 | 1.14–1.30 | 0.38–0.47 | 0.35–0.42 | 0.42–0.51 | ||||
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n = 5 | 1.32–1.46 | 0.56–0.61 | 0.40–0.41 | 0.46–0.52 |
Mesoscutum with four pairs of prickly setae. Metatibia with three short rows of thick setae, lacking a tightly packed row of short setae on the dorsum (Fig.
Pore fields on abdominal ventrum small oval; pores loosely packed (Fig.
Male terminalia: Proctiger slightly curved backwards (Fig.
Female terminalia (Fig.
Head and antennae of
Fore wing of
Hind legs and wax-secreting fields of
Holotype: ♂, CHINA: Hainan, Danzhou, Nada, 131 m,
Named after the scientific name of the host plant.
Based on a brief observation in the field, this species was found free living, both immatures and adults are sparsely scattered across the abaxial surface of leaves (no preference for young leaves or shoots is displayed). The immatures do not induce any form of gall or leaf rolling, and from the sectasetae on body margin they produce wax threads of varying lengths, of which the ones from the terminal bulges of abdomen are longest (Fig.
Dorsum of head and thorax brown with large areas of brown patterns. Antennal segments VI and VIII each with two additional rhinaria (Fig.
Structures: Setae on dorsum of body relatively short (Table
Mesoscutum with 5 pairs of prickly setae (Fig.
Pore fields on abdominal ventrum large oval, with pores loosely packed (Fig.
Male terminalia: Proctiger slightly curved backwards apically (Fig.
Female terminalia (Fig.
Male terminalia of
Female terminalia of
Fifth instar immature of
CHINA: 2 ♀, Zhejiang, Qingyuan, Baishanzu, 1300-1500 m, ex
Fore wing with yellow bands (Fig.
Ground color yellow. Compound eyes grey. Long and thick setae on dorsum black. Ocelli yellow. Antennae yellow, with black spices on segments III-VIII; segments IX-X entirely black. Fore wing hyaline, with four obliquely transverse yellow stripes (Fig.
Structures: Setae on dorsum of body relatively long (Table
Mesoscutum with four pairs of prickly setae (Fig.
Pore fields on abdominal ventrum long, narrow and curved; pores tightly packed (Fig.
Male terminalia: Distal 1/3 of proctiger with posterior surface split and replaced with membranous tissue (Fig.
Female terminalia (Fig.
Fifth instar immature of
Various parts of
Comparison of coxa of different psyllid taxa.
CHINA: 18 ♂, 21 ♀, 10 fifth instar immatures, Fujian, Shaxian, ex
Paramere with large area of netlike grains covering the inner surface of apical half, anterior margin serrated (Figs
Structures: Setae on dorsum of body relatively short (Table
Mesoscutum with five pairs of prickly setae. Metatibia with one row of thick setae ventrally, and with a tightly packed row of long setae on the dorsum. Pulvilli narrow. Fore wing with broad cell r1, cell cu1 tallest in the middle; vein M3+4 with one seta on the base; surface spinules rather minute, widely spread across a large area in distal cells; fields of radular spinules unclear (Fig.
Pore fields on abdominal ventrum large oval, with pores loosely packed.
Male terminalia: Proctiger completely sealed, with apex slightly thickened (Fig.
Female terminalia (Fig.
Lateral aspect of thorax.
Comparison of ventral aspect of thorax.
CHINA: 49 ♂, 69 ♀, Tibet, Nyingchi, Mafenggou, 3050 m, ex
The similarities and differences of the two genera have been listed by
Psyllids jump powerfully, then cast a mid-air rotation. Such a somersault, however, involves not only the strong muscles supported by the specialized metathoracic furca, enlarged metatrochanteral tendon and expanded meral part of the metacoxa but also a kicking of both hind legs on parallel planes (
To discuss the formation of the enlarged and twisted metacoxa, one must seek reference from the mesocoxa. Mid and hind legs are both appendages of winged thoracic segments; additionally, in immature psyllids, they are equal in every detail, although differing from the forelegs in some aspects, indicating that hind legs of adults emerged from the model of mid legs. An undescribed
The mesocoxa (Fig.
Compared with mesocoxa, the metacoxa (Fig.
By contrast,
Most psyllids possess an apophysis on meso- and metepisternal complex, termed ‘trochantinal apodeme’ (
According to
Habitus, showing difference in the ways that hind legs are held.
All the four members of
Psyllid immatures possess wax-secreting pores on their caudal plates. These pores are arranged in various patterns, mostly with a basic circum-anal ring (possibly homologous with the circum-anal ring of female adults), and on many occasions with extra pore fields (Brown and Hodlinson 1985). Extra pore fields can sometimes be succeeded by the adults, appearing on their more terminal (usually segments 7 and/or 8) abdominal tergites, e.g.
This is the first time that a psyllid adult is found with such fields of wax-secreting pores. Compared with those of whiteflies, wax pore fields of
Alternatively,
Comparison of characters among whiteflies, fossil pan-psyllids,
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Other |
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Median suture of vertex | Absent | Absent | Absent | Absent ( |
Present (with a few exceptions such as |
Frons | Completely fused with gena | Completely fused with gena | Independent from gena | Completely fused with gena | Independent from gena |
Clypeus | Fused with gena | Fused with gena | Attached to gena by a pair of sclerites | Attached to gena by a pair of sclerites | Attached to gena by a pair of sclerites |
Labium | Long, originated before prosternum | Long, originated before ventrum of prothorax | Long, originated between procoxae | Shortened (two-segmented), originated between procoxae | Shortened (pseudo-three-segmented), originated between procoxae |
Extra sclerites posterior to base of thoracic furca | Present | - | - | Present | Usually absent, but present in |
Modification of metapleurite | - | - | - | Incomplete | Complete |
Modification of metacoxa | Slight enlargement | Slight enlargement | Slight enlargement | Significant enlargement, slight backwards twist | Significant enlargement, backwards-twisted at 90° |
Enlargement of trochanteral tendon | None | - | - | Slight | Significant |
Reduction of tergite of abdominal segment 1 | Tergite complete | - | - | Consistent in the middle | Reduced to two separate small lateral sclerites |
Wax plates | Present | - | - | Present | Absent |
Aedeagus | One-segmented | One-segmented | - | One-segmented | Double-segmented |
Male proctiger | Fused with subgenital plate | Fused with subgenital plate | - | Posterior aspect completely sclerotized and finely enveloped | Posterior aspect membranized |
Valvulae dorsales of ovipositor | Without flag lobe | - | - | Without flag lobe | With flag lobe (except for |
Ocular setae of last instar immature | Absent | - | - | Present | Present or absent |
Tarsal arolium of last instar immature | Absent | - | - | Absent | Present |
In the schematic phylogenetic tree (
In addition to the obvious synapomorphies of
Another species,
Phylogeny of
Thanks are due to Dr. Yorio Miyatake of Osaka Museum of Natural History, Japan and Dr. Hiromitsu Inoue of Institute of Fruit Tree and Tea Science, National Agriculture and Food Research Organization, Japan, for their kind loans of specimens of