Dicladispa testacea ( Linnaeus 1767 )

Świętojańska, Jolanta, Borowiec, Lech & Stach, Małgorzata, 2014, Redescription of immatures and bionomy of the Palaearctic species Dicladispa testacea (Linnaeus, 1767) (Coleoptera: Chrysomelidae: Cassidinae: Hispini), a leaf-mining hispine beetle, Zootaxa 3811 (1), pp. 1-33 : 2-30

Dicladispa testacea ( Linnaeus 1767)

Egg ( Figs. 1–3 ).

Elongate-oval, yellowish-white ( Figs. 3 ), deposited singly or quite often two eggs within the hole produced by female on the underside of host plant leaf ( Figs 1–3 ). The only one egg was measured. Length of measured egg: 0.97 mm, width 0.42 mm.

Larva ( Figs 12 , 44–60, 63–116 ).

General body structure is the same in all examined larvae, the difference between each instar are pointed in the description given below.

Measurements are presented in Table 1 . Length was measured without head, from anterior border of pronotum to the tip of body; width of body was measured across pronotum (at base) and abdominal segment IV (in the middle).

Body distinctly flattened dorso-ventrally ( Fig. 65 ), larva of instar 1, 2 and 3 (or 4) elongate ( Figs 12 , 44, 45, 63 , 64), in instar 1 and 2 the pronotum slightly wider than abdominal segments ( Figs 63, 64 , 72 ), in instar 3 (or 4) body parallelsided (pronotum as wide as abdominal segments) whereas mature larvae are elongate-oval and widest across abdominal segment IV–V ( Figs 46, 47, 59, 60 , 84 ). Body of alive as well as alcohol-preserved larvae yellowish-white with two irregular brown patches on pronotum, brown posterior half of abdominal segment VIII, brown triangular patch on prosternum, dark brown spiracles, brown head and legs ( Figs 59, 60 ).

Dicladispa testacea length of body width of prothorax width of abdominal width of head [mm]

[mm] at base segment IV

[mm] [mm]

Body with 8 pairs of lateral scoli placed only on abdominal segments ( Figs 44–47, 59, 60 , 63, 64 , 68, 69 , 97 , 98 ). Lateral scoli short, approximately the same length, without lateral branches but with 2 setae at base: one placed anteriorly, second—ventrally. All lateral scoli apically armed with seta ( Fig. 99 ).

Granulation of body distinct in all examined instars ( Figs 44, 45, 63–65, 68, 69 , 72–78, 80–102 ). Minute setae at anterior border of each tergite and sternite (except for sternite of VIII segment); tergites and sternites covered with short pointed setae ( Figs 44–47, 75 , 81–83 ). Tergites of meso-, metathorax, abdominal segments I–VII and sternites I–VII of abdomen with transverse groves ( Figs 44–47, 59, 60 , 63, 64 , 72, 74–76 , 82 , 84, 86, 89, 90 ). Sternites of meso- and metathorax with two structures shaped similarly to the transverse grooves of other sternites and tergites but distinctly shorter ( Figs 45, 47, 64 , 73 , 85, 87, 88 ). Posterior border of each transverse groove with distinct asperites ( Figs 68 , 74, 75, 77 , 88 ). Asperites also present at the anterior border of pronotum ( Figs 78, 79 ).

Pronotum on each side with 12 setae arranged in constant pattern as in Figs 44, 46. Meso-, metanotum with 6 minute setae at anterior border (a pair in the middle and a pair on each lateral side); a row of 10 setae running across segment; and a group of 5 setae on each side of tergite laterally. One seta—two times longer than other setae of tergites and sternites—placed on slightly visible protuberance on each side of meso- and metanotum. Abdominal tergites I–VII with 4 minute setae at anterior border (sometimes in mature larvae abdominal tergite I with 6 minute setae at anterior border); two rows of setae running across segment, both with 4 setae; 2 setae and campaniform sensillum placed close to each spiracle. Abdominal tergite VIII with 2 minute setae at anterior border medially; three rows of setae running across segment: anterior with 4 setae, next with 8 setae; and posterior with 2 setae (placed between spiracles). Posterior border of abdominal segment VIII in instar 1 and 2 with 8 pointed setae, in mature larvae each seta placed at the top of short process ( Figs 44–47, 77 , 91–94 ).

Prosternum in posterior half with two pairs of pointed setae medially and 2 setae on each lateral side at base of leg ( Figs 45, 47). Meso- and metasternum with 4 minute setae at anterior border; two pairs of pointed setae medially; and one seta on each lateral side at base of leg. Abdominal sternites I–VII with a pair of minute setae at anterior border medially; with row of 6 setae running across segment medially; and 3 setae on each side of sternite laterally. Abdominal sternite VIII with rows of 4 setae running across segment in anterior part and one seta in posterior part at base of each spiracle. Four setae along anterior base of anus. Segments which build anus not elevated ( Figs 45, 47, 60 , 64 , 77 , 84 , 93 ).

Nine pairs of distinct spiracles: one on thorax and 8 on abdomen ( Figs 63 , 70, 71 , 95, 96 ). In instar 1 and 2 diameter of spiracles approximately the same size, including spiracles of VIII abdominal segment, only spiracles of thorax slightly more elevated than the others. In mature larvae as in younger instars, spiracles of thorax slightly more elevated than those on abdomen, diameter of spiracles of abdominal segments I–VII approximately the same size, but spiracles of abdominal segment VIII distinct, elevated and conical ( Figs 91–94 ).

Head well sclerotized, prognathous, partially retracted into pronotum ( Figs 48, 49 , 59, 60 , 63–65 , 104, 106, 108 ). Epicranial stem absent; median endocarina wide, extending between frontal arms; frontal arms V-shaped, fronto-clypeal suture absent, clypeo-labral suture well developed ( Fig. 109 ). Clypeus wider than long, slightly marked, without setae and campaniform sensilla.

Six stemmata on each side of head, the smallest placed ventrally, hardly visible ( Figs 48, 49 , 107 ).

Head on each side with 4 small vertical pointed setae (V 1–4) and four frontal rows of pointed setae: row Fa with 3 setae, Fb with 5 setae, Fc with three setae, Fd with single seta and Fe absent. Temporal side of head with 4 setae (T 1–4) and three campaniform sensilla. Several campaniform sensilla present: one close to setae on vertex, one close to seta Fa1, one or two close to setae Fb1 and Fb2, one between setae Fb3 and Fb4, three close to seta Fd1, three setae on temporal side ( Figs 48, 49 , 104–108 ).

Antennae 2- segmented, set in membranous ring ( Figs 52 , 116 ). Both segments stout, approximately as wide as long. First segment with 3 campaniform sensilla, second segment with a group of sensilla at the apex: one prominent (sensory appendix), one long seta, 3 shorter setae and 2 small peg-like sensilla.

Labrum approximately two times longer than wide, anterior margin shallowly emarginate ( Figs 50, 51 , 66 , 104, 109–111 ), on dorsal surface: two setae on each lateral side; two pairs of campaniform sensilla medially; and four stout setae on each side close to anterior margin. Mid part of ventral surface (epipharyngeal area) with three pairs of campaniform sensilla at base; two irregular groups of a few small sensilla in anterior part; and numerous spines medially and on each lateral side.

Mandibles heavily sclerotized, with two apical teeth: one distinct, conical, the second blunt at the top and slightly moved back ( Figs 53, 54 ). Two setae placed very close to each other and two campaniform sensilla ( Figs 106 , 116 ).

Maxillae and labium connate ( Figs 55 , 108 , 112 ). Each stipes (st) with seta at base and 3 campaniform sensilla in anterior part. Palpifer (pp) with 2 campaniform sensilla. Mala (mal) not distinctly bordered from palpifer ( Figs 67 , 114 ), bears: six long stout setae, one short blunt seta (or peg like sensillum?) and one campaniform sensillum at the top; and two setae below apex. Maxillary palp two-segmented: first segment with one campaniform sensillum; second segment with a group of small peg-like sensilla at the apex. Labial palp (lp) one-segmented with a group of small peg-like sensilla at the apex ( Figs 55 , 112, 113 ). Hypopharynx (hyp) covered with numerous spines, at base with: two or three pairs of sensilla (campaniform sensilla or sensilla celoconica—difficult to diagnose without histological examination) ( Figs 55 , 113, 115 ). Prementum (pre) with two campaniform sensilla, each placed at base of labial palp. Postmentum (post) with four setae and two campaniform sensilla.

Legs stout, consist of three segments: coxa, femur and tibiotarsus. Tibiotarsus armed apically with claw ( Figs 56–58 , 100–103 ). Coxa with four setae placed along base on internal side, two setae placed dorsally and two setae on external side. One seta at base externally. Femur with 8 pointed setae: dorsally two setae and one campaniform sensillum placed in apical half and one seta in basal half; ventrally two setae placed in apical half and one seta in basal half; also in apical half one seta externally and one internally. A group of five campaniform sensilla and one short pointed seta on internal side of femur basally; two campaniform sensilla at base ventrally. Tibiotarsus at apex with heavily sclerotised, curved, single and simple claw armed with a pointed seta basally. Claw and pointed seta surrounded by a complex of six setae. Two campaniform sensilla and seta above claw. Tibiotarsus also with two setae dorsally. At base of claw distinct pulvilli.

Pupa ( Figs 61, 62 , 117–136 ).

Measurements are presented in Table 1 . Length was measured without head, from anterior border of pronotum to the tip of body; width of body was measured across pronotum (at base) and abdominal segment IV (in the middle).

Body flattened dorso-ventrally, elongate-oval, the widest across abdominal segment IV and V ( Figs 61, 62 ). Colour of alive as well as alcohol preserved pupa yellowish-brown.

Head visible in dorsal view ( Figs 61 , 117 ).

Prothorax trapezoidal in shape, lateral edge of pronotum with four processes: three of them armed apically with single seta ( Figs 118 , 129, 130 ).

Meso-and metathorax without lateral scoli. Elytral portion distinctly visible ( Figs 61, 62 , 119 ).

First abdominal segment without lateral scoli ( Figs 61, 62 ). Each lateral side of segments II–V with single and simple scolus and one pointed seta which on segments IV and V is placed on low tubercle. Each lateral side of segments VI–VIII with 2 scoli and pointed seta on prominent tubercle ( Fig. 131 ), more distinct than on segments IV and V (in shape similar to lateral scoli). Each scolus apically armed with one seta. Posterior lateral scolus of segments VI and VII with lateral branch directed posteriorly without any seta. Segment VIII additionally with two broad, dorso-ventrally flattened processes placed at posterior border ( Figs 61, 62 , 121 , 128 ). Each flat process apically with usually 5 tubercles (rarely 4 or 3). Each tubercle apically armed with single seta.

Abdominal segments I–V with a pair of spiracles ( Figs 132–136 ). Spiracles of first four segments of similar diameter, distinctly marked and elevated but spiracles of the segment V are the most prominent, elongated into cylindrical appendage (respiratory horns) with elongate-oval outer spiracular opening.

Whole body including head, antennae, legs and elytral portion distinctly granulate ( Figs 117–123, 128–132, 134 ), abdominal sternites also with distinct asperites ( Figs 124–127 ). Head and thoracic tergites with sparse pointed setae ( Figs 117, 119 ). First abdominal tergite with one row of tubercles placed posteriorly. Tergites of abdominal segments II–VIII with two rows of distinct tubercles, some of them with pointed seta apically ( Figs 120, 122 ). Abdominal sternites with row of setae placed on tubercles running along posterior border ( Figs 124, 125 ). Sternites VII and VIII with row of setae and with additional tubercles without setae ( Figs 124, 126, 127 ). Tubercles without setae, look like tubercles on abdominal tergites.

Figures

FIGURES 1 – 6. Dicladispa testacea. 1, 3. eggs; 2, 4 – 6. mines of first instar larva, in Fig. 2 red arrow indicate place were egg was deposited.

FIGURES 7 – 12. Dicladispa testacea. 7 – 11. eggs; 12. second instar larva.

FIGURES 63, 64. Dicladispa testacea, first instar larva. 63. dorsal aspect; 64. ventral aspect.

FIGURES 65 – 71. Dicladispa testacea, first instar larva. 65. body laterally; 66. ventral side of labrum; 67. palpifer and mala, maxillary palp artificially collapsed; 68. spiracles of abdominal segments I – V; 69. lateral scoli of abdomen, ventral aspect; 70. spiracle of thorax; 71. spiracle of second abdominal segment.

FIGURES 72 – 77. Dicladispa testacea, first instar larva. 72. pro-, meso- and metanotum; 73. meso- and metasternum; 74. abdominal sternites; 75. abdominal sternite I; 76. abdominal tergites; 77. top of body ventrally.

FIGURES 78 – 83. Dicladispa testacea, fifth instar larva. 78. pronotum; 79. anterior margin of pronotum; 80. spiracle of thorax; 81. seta of pronotum; 82. mesonotum; 83. metanotum.

FIGURES 84 – 90. Dicladispa testacea, fifth instar larva. 84. body visible ventrally; 85. thoracic sternites and first two abdominal sternites medially; 86. abdominal sternites; 87. meso- and metasternum medially; 88. metasternum; 89. abdominal sternite V and VI, medially; 90. abdominal sternite II, medially;

FIGURES 91 – 97. Dicladispa testacea, fifth instar larva. 91. top of body dorsally; 92. spiracle at the top of body dorsally; 93. top of body, ventrally; 94. spiracle at the top of body, ventrally; 95. abdominal tergites II – IV, laterally; 96. spiracle of III abdominal tergite; 97. lateral scoli of abdominal segments V – VII, laterally.

FIGURES 98 – 103. Dicladispa testacea, fifth instar larva. 98. lateral scolus of I abdominal segment, ventrally; 99. seta at the top of lateral scolus of I abdominal segment; 100. leg, dorsal aspect; 101. tibiotarsus and pulvilli; 102. leg, ventral aspect; 103. pulvilli at the top of tibiotarsus.

FIGURES 104 – 109. Dicladispa testacea, fifth instar larva. 104. head; 105. minute setae at the top of head; 106. head laterally; 107. stemma and campaniform sensilla; 108. maxillae and labium; 109. labrum dorsally.

FIGURES 110 – 116. Dicladispa testacea, fifth instar larva. 110. labrum ventrally; 111. sensilla of ventral part of labrum; 112. maxillae and labium; 113. prementum and hypopharynx; 114. palpifer, mala and two-segmented maxillary palp; 115. sensilla of prementum; 116. mandibular with two distinct setae.

FIGURES 59 – 62. Dicladispa testacea. 59. mature larva dorsally; 60. mature larva ventrally; 61. pupa dorsally; 62. pupa ventrally.

FIGURES 48 – 55. Dicladispa testacea, larva, scale show differences in size between first and fifth instar larvae. 48. frontal side of head; 49. temporal side of head; 50. dorsal side of labrum; 51. ventral side of labrum; 52. antenna; 53, 54. mandibles; 55. maxillae and labium, ventrally. Abbreviations: hyp — hypopharynx; lp — labial palp; mal — mala; mpI — first segment of maxillary palp; mpII — second segment of maxillary palp; post — postmentum; pp — palpifer; pre — prementum; st — stipes.

FIGURES 56 – 58. Dicladispa testacea, leg of larva, scale show differences in size between first and fifth instar larvae. 56. internal side of leg; 57. top of femur and tibiotarsus dorsally; 58. femur and tibiotarsus ventrally.

FIGURES 117 – 122. Dicladispa testacea, pupa. 117. top of head; 118. pronotum; 119. meso- and metanotum medially; 120. setae and sculpture of abdominal tergites V – VII; 121. top of body dorsally; 122. abdominal tergite V.

FIGURES 123 – 128. Dicladispa testacea, pupa. 123. leg; 124. abdominal sternite VI, VII; 125. setae of abdominal sternite VI; 126. seta of abdominal sternite VIII; 127. top of body ventrally; 128. processes of the top of body ventrally.

FIGURES 129 – 136. Dicladispa testacea, pupa. 129. lateral margin of pronotum; 130. processes with setae on lateral margin of pronotum; 131. lateral scoli of abdominal segments VI – VIII; 132. spiracle of first abdominal tergite; 133. inside spiracle of I abdominal tergite; 134 – 135. spiracle of V abdominal tergite; 136. inside spiracle of V abdominal tergite.

Tables

TABLE 1. Measurements of examined immature instars of Dicladispa testacea.

first instar larva 1.	1.00	0.59	0.53	0.36
2.	1.12	0.58	0.51	0.40
3.	0.92	0.55	0.46	0.40
4.	1.32	0.58	0.54	0.40
5.	0.92	0.60	0.52	0.41
6.	1.03	0.63	0.56	0.41
7.	1.23	0.65	0.56	0.41
second instar 1.	1.00	0.69	0.63	0.46
2.	1.03	0.66	0.58	0.46
3.	1.20	0.68	0.56	0.46
4.	1.28	0.68	0.61	0.46
5.	1.92	0.70	0.60	0.46
6.	1.64	0.68	0.56	0.46
7.	1.55	0.71	0.65	0.48
8.	1.60	0.70	0.50	0.48
third or fourth (?) instar 1.	2.73	0.93	0.93	0.60
mature larva 1.	3.00	1.17	1.60	0.65
2.	2.70	1.20	1.65	0.65
3.	4.25	1.25	2.15	0.67
4.	4.10	1.25	2.25	0.70
5.	3.70	1.25	2.30	0.72
6.	3.95	1.25	2.27	0.68
7.	4.00	1.25	2.25	0.72
8.	4.00	1.25	2.10	0.68
pupa 1.	4.50	1.60	2.15	-
2.	4.60	1.60	2.00	-
3.	4.45	1.55	2.15	-
4.	4.00	1.35	1.85	-
5.	4.30	1.40	1.85	-
6.	4.00	1.40	2.00	-
7.	4.25	1.45	2.10	-
8.	4.00	1.30	1.65	-