First-instar larval morphology in the subtribe Lydina(Coleoptera, Meloidae, Lyttini), with discussion on its systematic value

Federica Turco, Andrea Di Giulio & Marco A. Bologna*

Dipartimento di Biologia, Universita degli Studi “Roma Tre”, Viale Marconi 446, 00146 Roma, Italy

Received March 2005, accepted February 2006Published online 12 October 2006

With 3 figures, 3 tables

Key words: Lydus, Alosimus, Oenas, triungulin, SEM analysis, comparative morphology.

Abstract

First-instar larvae of five species of Lydina, belonging to three genera – Lydus trimaculatus italicus Kaszab, L. europaeusEscherich, Oenas crassicornis (Illiger), O. tarsensis (Abeille de Perrin), and Alosimus chalybaeus (Tauscher) – are described,and new observations on two species previously described Oenas afer (Linnaeus) and Alosimus cirtanus (Lucas) are carriedout. The larval morphology of Lydina, studied through light and scanning electron microscope and compared to that of otherLyttini genera, does not support the taxonomic value of the Lydina subtribe since no synapomorphies for this lineage arerecognised.

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Introduction

The blister beetle tribe Lyttini (Meloidae, Meloi-nae) is a quite heterogeneous group world-widedistributed with the exception of the Australiancontinent (Bologna, 1991). It includes about 22genera whose phylogenetic relationships remainquestionable (Bologna & Pinto, 2001).

Kaszab (1959; 1969) divided Lyttini into twosubtribes, Lyttina and Lydina, primarily usingcharacters related to the claws and wing venationof adults. The first lineage, considered as primi-tive, is a speciose and heterogeneous group,which includes about 15 genera, characterised bysmooth claws in the adults. The second lineage,considered as derived, includes the genera Alosi-mus Mulsant, Eolydus Denier, Lydus Dejan,Muzimes Aksentjev, Oenas Latreille, Pseudosy-baris Saha (of uncertain taxonomic value) andSybaris Stephens, all of them showing serrateclaws in adults and wing venation different thanLyttina (Kaszab, 1959). Slightly serrate claws are

also present in few species of Lyttina (some LyttaFabricius, one Lydomorphus Fairmaire, seeBologna & Pinto, 2002).

The first-instar larvae, or triungulins, of sev-eral Lyttini genera have been described: Ber-beromeloe Bologna (Cros, 1912b; Bologna,1989), Trichomeloe Reitter (Cros, 1934a; Bolog-na, 1989; unpublished), Cabalia Mulsant & Rey(Cros, 1928b), Lagorina Mulsant & Rey (Cros,1934b), Lydomorphus (Bologna & Aloisi, 1992;Bologna et al., unpublished); Lytta (for syn-thetic information see: Beauregard, 1890;MacSwain, 1956; Bologna, 1991), Prolytta Kas-zab (Bologna & Di Giulio, 2002) and Prionoto-lytta Peringuey (Bologna & Di Giulio, 2003)for the Lyttina, and Lydus, Alosimus andOenas for the Lydina (Table 1). Triungulins ofsome other South American Lyttina genera aregoing to be described (Bologna et al., unpub-lished), and their morphology has been studiedin a phylogenetic analysis (Bologna & Pinto,2001).

Mitt. Mus. Nat.kd. Berl., Dtsch. entomol. Z. 53 (2006) 2, 213–222 / DOI 10.1002/mmnd.200600017

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

* Corresponding author: e-mail: bologna@uniroma3.it

Most of the papers concerning larvae of Lytti-ni are mere taxonomical descriptions. A com-parative analysis of larval morphology within the

tribe has been carried out by MacSwain (1956),who reported some affinities between Lydus andOenas, and by Bologna & Pinto (2001) in a cla-distic revision of the family Meloidae.

Larval characters have been combined to adultand bionomical characters in assessing the phylo-genetic relationships within the family Meloidae(Bologna & Pinto, 2001). This cladistic analysisinadequately supports the monophyly and thelimits of the tribe Lyttini but, at the same time,supports the monophyly of Lydina, emerging asa distinct clade.

Moreover, a comparative analysis of the sexualbehaviour among different Lyttini genera (Turco& Bologna, 2005) does not support the distinc-tion of the Lydina lineage.

The first aim of the present paper is thedescription of triungulins of five species of Lydina,previously unknown: Lydus trimaculatus italicusKaszab, L. europaeus Escherich, Oenas crassicor-nis (Illiger), O. tarsensis (Abeille de Perrin), andAlosimus chalybaeus (Tauscher). Additional in-formation are also given for two other speciespreviously described in literature: Alosimus cirta-nus (Lucas) (Cros, 1922a; 1928a) and Oenas afer

Turco, F., Di Giulio, A. & M. A. Bologna, Lydina larval morphology (Coleoptera, Meloidae, Lyttini)214

Table 1Summary of the present knowledge about Lydina first instarlarvae (triungulin and first grub) and related references.

Genus Species withdescribed larvae

References

Lydus L. trimaculatusitalicus

Present paper

L. europaeus Present paperL. algiricus Cros, 1912aL. marginatus Cros, 1919; 1928a;

MacSwain, 1956

Oenas O. crassicornis Present paperO. tarsensis Present paperO. afer Cros, 1919; 1922b;

MacSwain, 1956;Present paper

Alosimus A. chalybaeus Present paperA. cirtanus Cros, 1922a; 1928a;

Present paperA. viridissimus Cros, 1911; 1928a

Muzimes None

Sybaris None

Eolydus None

Pseudosybaris None

Table 2Sources and rearing data of the material used for the descriptions. Triungulin specimens of each record refer to one singlebatch of a single female.

Species Vialnumber

Slidenumber

N. ofspecimens

Sources Day ofcollection

Days of oviposi-tion/hatching

Lydustrimaculatusitalicus

253 M203-M206-M261

150 Italy, Abruzzi, S. Buono (CH),F. Trieste

07. VII. 1994 07/19. VII. 1994

418 M352 50 Italy, Latium, Maccarese (RM),41�520 N 12�160 E

25. VI. 1999 28. VI./12. VII. 1999

465 –– 60 Italy, Latium, Tolfa (RM),S. Severa-Tolfa

14. VI. 2002 16. VI./01. VII. 2002

466 –– 200 Italy, Latium, Maccarese (RM),41�520 N 12�160 E

21. VI. 2002 25. VI./02. VII. 2002

490 –– 200 Italy, Latium, Tolfa (RM) 7. V. 2003 28. V./09. VI. 2003

Lyduseuropaeus

414 M353 400 Greece, Ioanina, road to Polidoro 09. VI. 1999 10./23. VI. 1999

Oenascrassicornis

412 M355 70 Greece, Fthiotida, 10 Km SDomokos, 39�040 N 22�190 E

06. VI. 1999 06./19. VI. 1999

413 M354 30 Greece, Atiki, Erythres-Thiva,38�130 N 23�200 E

05. VI. 1999 08./21. VI. 1999

416 –– 30 Greece, Atiki, Erythres-Thiva,38�130 N 23�200 E

05. VI. 1999 06./23. VI. 1999

Oenastarsensis

516 M405 150 Iran, Fars, Firouzabad, 40 Km SEKazeroun, 750 m, 29�170 N 51�550 E

08. V. 2004 09./18. V. 2004

Oenas afer 535 –– 30 Morocco, road 3485 Khenifra-Aguelmame Azigza, about 2 Km EKhenifra

24. V. 2004 26. V/11. VI. 2004

Alosimuschalybaeus

121 M116/M120

50 Turkey, vil. Mersin, Mut 07. V. 1991 08./22. V. 1991

Alosimuscirtanus

536 M404 50 Morocco, Meknes prov., road P21,35 Km NW Midelt, 32,87392� N–4,94744� W

23. V. 2004 28. V./13. VI. 2004

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim http://museum-dez.wiley-vch.de

(Linnaeus) (Cros, 1919; 1922b; MacSwain, 1956).A comparative analysis of these larvae withthose previously described for the entire tribeLyttini is performed to verify the consistence andsystematic value of the subtribe Lydina.

Materials and methods

First-instar larvae of Lydus europaeus, Oenas afer, O. crassi-cornis, O. tarsensis, Alosimus chalybaeus, and A. cirtanus arecomparatively described in relation to the extensive analysisof Lydus trimaculatus italicus triungulin.

Eggs were put into vials plugged by cotton and kept in athermostatic cell (25 �C) with a photoperiodic control.

The first-instar larvae described in this work are preservedin 70 % ethanol (M. A. Bologna collection, University“Roma Tre”, Rome, Italy) (Table 2). Some of the triungulinswere cleared and mounted on slides in Canada balsam andanalysed by a Leitz Laborlux S light microscope. Several spe-cimens were critical point dried, mounted on stubs, gold sput-tered and observed by a Philips XL30 scanning electronmicroscope (L.I. M.E., University “Roma Tre”).

The terminology of larval features follows MacSwain(1956), Lawrence (1991), and Bologna & Pinto (2001). Cer-tain characters used in the larval chaetotaxy were adoptedfrom notational conventions suggested by Selander (1990)and Bologna & Di Giulio (2002). Main measures of the tri-ungulins are reported in Table 3.

Results

First-instar larval morphology of the genus Lydus

Morphological characters diagnostic for the tri-ungulins of this genus are represented by the fol-

lowing features: body elongate (ratio betweenbody length and width 6.7–7.3 versus ratio 5.1–5.4 in Oenas and Alosimus); head with parallelsides; external setae of Medial Row (MR, seebelow) on abdominal segments II–VIII veryelongate (Figs 1a–b, 2a–d).

Lydus trimaculatus italicus Kaszab

Triungulin campodeiform; body elongate, subpar-allel-sided. Colour of membranous areas yellow-ish, head, legs and sclerites light brown. Tergitesof thorax and abdomen entire and well sclero-tised; sternites of thorax and abdomen membra-nous, with the exception of the abdominal ster-nite IX and small areas around sternal setae.Cuticle reticulate with transverse polygonalmeshes, more evident around tergites.

Head subquadrate, greatest width at the levelof the stemmata; sides parallel and slightlycurved basally; basal elevation absent; anteriormargin slightly rounded (Fig. 2a). Epicranialsuture Y-shaped; frontal arms subparallel, notreaching the antennal insertions. Stemmata circu-lar, convex and dorsolaterally placed. Frontocly-peal region with 16 setae; apex of frontoclypeuswith one transverse row (frontoclypeal row,FCR) of 4 pairs of setae: FCR1 similar in lengthto FCR3, FCR2 longer than the others; 1 addi-

Mitt. Mus. Nat.kd. Berl., Dtsch. entomol. Z. 53 (2006) 2 215

Table 3Ranges of the main measures of the described first-instar larvae (in micrometers). In parentheses is indicated the number ofexamined slide-mounted specimens.BL: body length, HL: head length, HW: maximum head width, DSt: diameter of stemmata (when elliptical, the length of bothaxes are reported), EpS: basal stem of epicranial suture, AnL: antennal length, ASL: antennal seta length, PL: prothoraxlength, PW: prothorax width, AbL: abdominal length, AbW: abdominal maximum width, TS: terminal seta length, TSp: thora-cic spiracle maximum diameter, Asp: abdominal spiracle maximum diameter, LW: labrum width, SA: sensory appendix length,AIII: antennomere III length.

Lydus trimaculatusitalicus (8)

Lyduseuropaeus (3)

Oenascrassicornis (4)

Oenastarsensis (3)

Alosimuschalybaeus (8)

Alosimuscirtanus (3)

BL 1820––2000 2180––2280 1220––1360 1320––1400 1400––1460 1380––1440HL 184––208 240––248 184––208 200––216 200––216 216––232HW 192––208 216––224 192––200 208––224 216––224 280––288DSt 16 14� 16 16,5� 12 20� 16 23� 15 16� 14EpS 48––50 52 44––48 48––54 38––48 68––76AnL 68––76 72––74 54––60 62––64 50––54 58––66ASL 130––136 136––158 94––108 106––122 88––128 140PL 174––192 208––216 160––168 160––176 152––180 184––200PW 248––288 312 256––264 256––264 264 248––256AbL 1180––1260 1300––1340 640––700 680––700 740––800 780––820AbW 272––296 296––312 240––256 240––264 256––272 288TS 288––328 320 144––192 200––208 208––240 256––296TSp 32 36––38 26––30 32––34 22––26 22ASpI 30––32 32––36 24––26 22––24 18––22 20AspII––VII 31––36 35––41 15––15 16––18 13––12 13––12AspVIII 36––40 42 14 18––20 10––12 10LW 80––86 90 66––76 82––88 70––74 98––100SA 30––32 30 26––30 26 28––34 20––22AIII 36––38 36––38 30––32 36––38 26––34 28––34

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1http://museum-dez.wiley-vch.de

tional pair of setae present medially and slightlyanterior to FCR, between the FCR1 setae; 1 sen-sory pit between FCR2 and FCR3. Four pairs ofsubequal setae posterior to FCR along a curvedline, which parallels the arms of the epicranialsuture (setae 1–4 from the posterior to the ante-rior); 1 sensory pit present between setae 1and 2. The posterior half of each epicranial platedorsally with 4 minute setae and 1 pit longitudin-ally lined (basal row, BR) paralleling the basalstem of the epicranial suture; 1 pit at posterolat-eral corner. Anterior half with 9 pairs of setaeand 4 pairs of sensory pits: 1 pair of long setaeclose to the epicranial stem with 1 pit anteriorlyplaced; 1 pair of shorter setae anterior to theBR; 7 pairs of differently sized setae (includingthe ocular seta) and 2 pits encircling the stemma-ta. Ocular sensory pit distinctly anterior to thestemma; ocular seta placed internally to the ocu-lar pit just anterior to the level of the stemma.Posterior half of ventral surface of epicranialplate with 1 medial sensory pit. Anterior halfwith 4 pairs of setae and 4 pairs of sensory pitsarranged as follows: 2 pairs of setae transversallylined at the level of the cardo and 2 pairs ofsetae and 3 pits behind the antennal fossa; 1 pitinternally placed, close to the base of the maxillae.Labrum transverse and anteriorly directed with1 sensory pit and 22 setae of varying lengthtransversally arranged in three rows: anteriorrow with 4 pairs of setae and 1 pit; posterior rowwith 4 pairs of setae; ventral row with 3 pairs ofsetae. Antennae short, anterolaterally directed;segment I short, ring-like with 1 dorsal sensorypit (Fig. 2c); segment II distinctly asymmetricalwith the maximum length on the inner side, sub-equal or only slightly longer than I, with 3 longsetae (2 dorsal and 1 ventral), 1 minute dorsalseta near sensory appendix and 1 dorsal pit; sen-sory appendix on the outer side of the segmentII conical and large, lateral, about as long as seg-ments I and II together; segment III slender andlong, cylindrical, about 2.5 times as long as II,with a long apical seta (about twice as long asthe entire antenna), 3 long subapical setae, 2 lat-eral (1 on outer and 1 on inner sides) and 1 dor-sal; 1 minute seta near the base of apical seta.Mandibles subtriangular (Fig. 2b) divided by agroove in a troncoconical base and an apical halfnarrowing and abruptly bending inward; entalsurface medially keeled and with 2 edges: 1 ven-tral smooth; 1 dorsal with about 10 spine-liketeeth upcurved; outer margin of mandible with2 setae, 1 sensory pit between them and 1 pit me-sodorsally. Maxillae with stipes subquadrate with

two rows of setae: anterior row with 2 long setaeand 1 internal pit; posterior row with 2 shortersetae and 1 pit between them; mala simple, lobi-form, slightly protruding, with 7–8 spiniformsetae; cardo transverse, subrectangular, with 1 veryshort seta; segments I and II of maxillary palpisubequal and ring-like; segment II with 2 subeq-ual setae, 1 dorsal on the external side and1 ventral on the internal side; segment III sub-quadrate, dorso-ventrally flattened and spoon-like (dorsally concave), about 1.5 times thelength of I and II together, with 1 basal and dor-solateral seta (inner side) and 1 ventrolateral pit(outer side); apex of segment III truncate, with athin transverse sensorial area composed of manysensilla, 25 conical subequal, 1 larger and cylind-rical, medially placed and 1 very small close tothe medial; outer side of segment III with 1 slen-der digitiform sensillum. Gula without setae.Submentum, mentum and prementum poorlysclerotised. Submentum with 2 setae; mentumwith two shorter setae; prementum with 4 setae,2 short and basal and 2 longer and anterior.Labial palpi with segments I and II subequal andsubquadrate, with 1 basal pit; segment I slightlyasymmetric with outer side longer than the innerside; segment II with an apical and circular sen-sorial area slightly swollen, composed of 10 coni-cal and subequal sensilla, 1 larger and cylindrical,medially placed and 1 very small close to themedial.

Thorax with segments subquadrate, broaderthan head; prothorax slightly wider than meso-and metathorax; margins of each thoracic seg-ment rounded. Ecdysial line complete on pro-and mesonotum, and restricted to anterior halfon metanotum. Each half of pronotum with12 setae and 5 pits symmetrically placed along3 transverse, subparallel rows; anterior row (AR)with 4 setae and 3 pits; medial row (MR) with4 setae and 1 pit irregularly lined; posterior row(PR) with 4 setae and 1 pit; prosternum with3 pairs of medial setae arranged longitudinallyand 1 pair anterior. Mesonotum with AR com-posed of 4 setae very irregularly disposed; MRwith 6 setae and 1 pit; PR with 4 setae and 2 pits;3 pairs of medial setae on mesosternum, theanterior pair extremely short. Setae of meta-thorax similar in number, position and relativedimensions to those of mesothorax.

Legs slender, coxa conical and elongate, with1 small apical seta, 4 elongate medial setae,transversally arranged, gradually decreasing inlength, 3 minute basal setae and 1 pit; trochanterwith 4 apical setae and 4 pits; femur with 6 setae

Turco, F., Di Giulio, A. & M. A. Bologna, Lydina larval morphology (Coleoptera, Meloidae, Lyttini)216

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim http://museum-dez.wiley-vch.de

Mitt. Mus. Nat.kd. Berl., Dtsch. entomol. Z. 53 (2006) 2 217

Fig 1. Habitus of first instar larvae. A – Lydus trimaculatus italicus, lateral view; B – Lydus trimaculatus italicus, dorsal view;C – Oenas tarsensis, lateral view; D – Alosimus cirtanus, lateral view; E – Oenas crassicornis, lateral view; F – Oenas afer, lat-eral view. Scale bars: A, B = 500 mm; C–F = 200 mm.

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1http://museum-dez.wiley-vch.de

and 1 pit, the longest ventral femoral seta, muchshorter than femur; tibiae and claws increasingslightly in length from pro- to metathorax; tibiaeslightly tapered at apex and with 5 longitudinalrows of 5–7 moderately long setae; claw conico-falcate, thin, acute and slightly curved at apex,with 2 setae different in length inserted at differ-ent level near base (the apical distinctly longerthan the basal).

Spiracles round, internally spongy with whit-ish protuberances. Peritreme slightly elevatedand with deeply papillate internal margin.Mesothoracic spiracle anterolateral in position.Abdominal spiracles distinctly dorsal (lateroter-gites fused with tergites) and increasing in diam-eter from segment I to VIII (Figs 1a–b).Abdominal spiracle I slightly smaller thanmesothoracic.

Abdomen distinctly longer than head andthorax together, subparallel sided; segments II–VII transverse and subequal; segment I subequalto segment VIII and slightly smaller than theothers; segment IX, the smallest, rounded; ster-nal abdominal area membranous. Tergites with3 transverse rows of setae – their arrangementon each half of tergite as follows: AR with 3setae (4 on tergite I) and 1 pit; MR with 3 setaeat the level of the spiracle, 2 minute internal and1 external (very long in segments II–VIII); PRwith 7 setae differently sized and 1 pit. AR andMR of tergite IX with the same setation of seg-ments II–VIII, PR composed of 5 elongatesetae, longer than the homologous of segmentsII–VIII, and 1 pair of very long setae (caudalsetae), slightly shorter than the last three abdom-inal segments combined. AR and MR of sterni-tes I–IX with 1 pair of minute medial setae each,PR with 4 pairs of setae (3 pairs on segment I),the 2 outer pairs (1 pair on segment I) very long(except on segments IX). Abdominal apex (seg-ment X or pygopod) membranous, transversallydivided in two parts: dorsal part semicircularwith 6 extremely small setae transversallyarranged, ventral part longitudinally divided in2 lobes, moderately produced.

Lydus europaeus Escherich

Similar to L: trimaculatus, except for the follow-ing characters.

Sensory appendix large and slightly roundedat apex; segment III cylindrical, about 2 times aslong as II (Fig. 2d).

First-instar larval morphology of the genusOenas Latreille

Morphological diagnostic characters for the tri-ungulins of this genus are represented by the fol-lowing features: head with rounded sides andmaximum width of the head at the level of stem-mata (Figs 1c, 1e–f, 3).

Oenas crassicornis (Illiger)

Similar to L: trimaculatus, except for the follow-ing characters.

Head subquadrate (Fig. 3e), slightly wider thanlong. Epicranial suture Y-shaped; frontal armsevidently sinuate and reaching the antennal in-sertions. Stemmata dorsally placed. Mandibleswith apical half regularly curved and about twiceas long as the basal part; ental surface of mand-ibles medially concave, with 2 edges: 1 ventralsmooth and 1 dorsal with about 8 subtriangularteeth. Segments II of maxillary palpi slightlyshorter than I; segment III about twice as longas the length of I and II together.

Thorax with segments transverse, slightly nar-rowing from pro- to metathorax; prothorax dis-tinctly wider than head; margins of each thoracicsegment rounded. Legs with coxae short andbroad; tibiae with 5 longitudinal rows of 4–5setae.

Abdominal spiracle I as wide as the mesothor-acic and distinctly larger than the other abdom-inal spiracles; spiracles II–VIII subequal, abouthalf the diameter of I.

Abdomen about as long as head and thoraxtogether, slightly fusiform; segment I distinctlywider than VIII. PR of tergite IX with setaesubequal to the homologous of segments II–VIII; caudal setae subequal to the last twoabdominal segments combined (Fig. 1f).

Oenas tarsensis (Abeille de Perrin)

Similar to O: crassicornis except for the followingcharacters.

Dorsal edge of mandible ental surface withabout 7–8 spine-like upcurved teeth.

Thorax with segments transverse, broader thanhead.

Abdominal spiracle I about half of mesothor-acic and slightly larger than II. Caudal setaesubequal to the last three abdominal segmentscombined (Fig. 1c).

Turco, F., Di Giulio, A. & M. A. Bologna, Lydina larval morphology (Coleoptera, Meloidae, Lyttini)218

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim http://museum-dez.wiley-vch.de

Oenas afer (Linnaeus)

The new examined material from Morocco(Table 2) agrees completely with the descriptionmade by Cros (1919; 1922b; see also MacSwain,1956) on Algerian specimens. In Figs 1e and 3f alateral view of the entire body and a dorsal viewof the head are reported.

This species differs from O: tarsensis for therelative dimensions of spiracles, which are similarto those of O: crassicornis, and from bothO: tarsensis and O: crassicornis for the greaterwidth of head.

First-instar larval morphology of the genusAlosimus Mulsant

Morphological diagnostic characters for the tri-ungulins of this genus are represented by thefollowing features: head slightly transverse(ratio between head width and length 1–1.1versus ratio 0.9–1 in Lydus and Oenas); maxi-mum width of the head at the level of anten-nal insertion; ocular pit posterior to ocular seta(Figs 1d, 2e–f).

Mitt. Mus. Nat.kd. Berl., Dtsch. entomol. Z. 53 (2006) 2 219

Fig. 2. Lydus trimaculatus italicus. A – Head, dorsal view; B – left mandible, dorso-lateral view (inner side); C – right antenna,dorsal view; D – Lydus europaeus, left antenna, ventral view; E – Alosimus cirtanus, head, dorsal view; F – right antenna,ventral view. Scale bars: A, E = 100 mm; B = 10 mm; C, D, F = 20 mm.

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1http://museum-dez.wiley-vch.de

Alosimus chalybaeus (Tauscher)

Similar to L: trimaculatus, except for the follow-ing characters.

Head subrectangular, transverse. Frontal armsof epicranial suture reaching the antennal inser-tions. Stemmata obliquely suboval, convex anddorsally placed. Ocular pit placed between ocu-lar seta and stemma. Labrum more narrow. Sen-sory appendix very large and longer than seg-

ments I and II together; segment III slender andlong as sensory appendix. Mandibles subtriangu-lar, with a very broad base, apical half abruptlynarrowing and regularly curved to the apex; dor-sal edge of ental surface with about 4 subtriangu-lar teeth. Segment II of labial palpi slightly long-er than I.

Thorax with segments transverse and subrec-tangular, subequal to head. Legs stouter with allarticles distinctly shorter and stouter, coxa with

Turco, F., Di Giulio, A. & M. A. Bologna, Lydina larval morphology (Coleoptera, Meloidae, Lyttini)220

Fig. 3. A–D – Oenas tarsensis. A – Head, dorsal view; B – head, ventral view; C – right antenna, ventral view; D – mouth-parts, frontal view; E – Oenas crassicornis, head, dorsal view; F – Oenas afer, head, dorsal view. Scale bars: A, E, F = 100 mm;B = 50 mm; C–D = 20 mm.

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim http://museum-dez.wiley-vch.de

some additional minute setae at the base; tro-chanter with 3 additional pits; femur with addi-tional 2 setae and 1 pit; tibiae with 5 irregularlongitudinal rows of 3–5 moderately long setae;claw shorter.

Abdominal spiracle I distinctly larger than theothers; spiracles II–VIII about half the diameterof I, slightly decreasing from II to VIII. Abdo-men slightly longer than head and thoraxtogether, slightly tapering from segment I to VIII;segments I–VII transverse. Tergites with setaemoderately short, AR of segments II–IX lacking1 pair of setae; PR of tergite IX with setae subeq-ual to the homologous of segments II–VIII.

Alosimus cirtanus (Lucas)

The new examined material from Morocco(Table 2) agrees completely with the descriptionmade by Cros (1922a; 1928a) on Algerian speci-mens. A lateral view of the entire body isreported in Fig. 1d, while a dorsal view of thehead and a particular of the antenna arereported in Figs 2e–f.

Similar to A: chalybaeus, except for the follow-ing characters.

Sensory appendix much shorter than antennalsegment III, about as long as I and II together.

Discussion

The first comparative analysis of Lyttini first-in-star larvae was performed by MacSwain (1956),who listed several structural features diagnosticfor this tribe, on the base of some Cros’ sugges-tions (1940). According to MacSwain (1956), theshort second antennal segment represents themost recognisable character. However, the phy-logenetic studies made by Bologna & Pinto(2001) on a larger set of Lyttini genera and char-acters, did not point out a monophyletic group,because some genera presently referred to thistribe seem to have an isolated position. Probablyit depends on the larval morphology of manygenera being still unknown.

MacSwain (1956) reported also some possiblelarval similarities between the genera Lydus andOenas in subquadrate head and sharply incurvedmandibles of triungulins. The Bologna & Pinto’sclassification (2001) grouped in a distinct cladethe three Lydina genera Lydus; Oenas andAlosimus; this clade is supported by the synapo-morphic condition of the abdominal spiracle I –

which is as wide as the half of tergum I and lar-ger than spiracle II – and by the adult serrateclaw character.

According to our results, both the head andspiracle characters are not clear synapomorphiesfor Lydina as a whole. In fact, the shape of thehead is distinctly transverse and not subquadratein Alosimus. The mandibles are sharply incurvedin other Lyttini, as in Berberomeloe. As concernthe large size of the abdominal spiracle I, weconfirm this distinctive character in Alosimusand Oenas. In Lydus, instead, the abdominalspiracle I is subequal in size to II, showing thegreatest diameter in the VIII; it is not so large inLydus trimaculatus and L: europaeus, while it issubequal to the remaining tergum length inL:marginatus (studied by MacSwain 1956 andBologna & Pinto 2001, but not examined againin the present paper).

In conclusion, the taxonomic value of the sub-tribe Lydina is not supported by the larval char-acters examined in the present study, since clearsynapomorphies for this lineage are not recog-nised in first-instar larvae. It is also not sup-ported by behavioural characters (Turco &Bologna, 2005).

We suggest that these genera represent a smalllineage inside the monotypic tribe Lyttini, sup-ported only by adult synapomorphies, but cannotbe taxonomically distinguished as a subtribe.

Acknowledgements

We want to thank all the naturalists who helped us in thefield work: Sayeh Serri (Insect Taxonomy Research Depart-ment, Plant Pests and Diseases Research Institute, Teheran),Serena Carloni, Paola De Salvo, Michele Giulianini, ChiaraSettanni (Rome), Monica Pitzalis, Pierluigi Bombi (Depart-ment of Biology, University “Roma Tre”, Rome), PaoloAudisio (Department of Animal and Human Biology, Uni-versity “La Sapienza”, Rome), Marzio Zapparoli (Depart-ment of Plant Protection, University “Tuscia”, Viterbo).

References

Beauregard, H. 1890. Les insectes vesicants. –– Paris (FelixAlcan), 544 pp. þ XIX pl.

Bologna, M. A. 1989. Berberomeloe, a new west Mediterra-nean genus of Lyttini for Meloe majalis Linne (Coleop-tera, Meloidae). Systematics and bionomics. –– Bollettinodi Zoologia 55: 359––366.

–– 1991. Coleoptera Meloidae. Fauna d’Italia. XXVIII. ––Bologna (Calderini), XIV þ 530 pp.

Bologna, M. A. & Aloisi, G. 1992. Systematics of Lydomor-phus Fairmaire 1882, with description of the first instarlarva of L. Dusalti (Dufour, 1821) (Coleoptera Meloi-dae). –– Tropical Zoology 5: 55––71.

Mitt. Mus. Nat.kd. Berl., Dtsch. entomol. Z. 53 (2006) 2 221

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1http://museum-dez.wiley-vch.de

Bologna, M. A. & Di Giulio, A. 2002. Review of the south-ern African genus Prolytta Kaszab, with a description ofthe first-instar larva, and bionomic and taxonomicremarks (Coleoptera: Meloidae). –– Invertebrate Systema-tics 16: 177––194.

–– 2003. Egg and first instar larval morphology of Prionoto-lytta binotata (Peringuey, 1888) and endemic southernAfrican species (Coleoptera: Meloidae). –– African Ento-mology 11: 213––219.

Bologna, M. A. & Pinto, J. D. 2001. Phylogenetic studies ofthe Meloidae (Coleoptera), with emphasis on the evolu-tion of phoresy. –– Systematic Entomology 26: 33––52.

–– 2002. The Old World genera of Meloidae (Coleoptera): akey and synopsis. –– Journal of Natural History 36:2013––2102.

Cros, A. 1911. Lydus (Alosimus) viridissimus Lucas. Sesmœurs –– sa larve primaire. –– La Feuille des jeunes Nat-uralistes 41: 191––199.

–– 1912a. Lydus algiricus L. Ses mœurs –– sa larve primaire.–– La Feuille des jeunes Naturalistes 42: 78––86.

–– 1912b. Moeurs et evolution du Meloe majalis L. –– Bulle-tin de la Societe d’Histoire naturelle de l’Afrique duNord 4: 45––48, 70––72, 93––96, 154––161, 181––190,209––215.

–– 1919. Notes sur les larves primaires des Meloidae avecindication de larves nouvelles. –– Annales de la SocieteEntomologique de France 88: 261––279.

–– 1922a. Notes sur les larves primaires des Meloidae avecindication de larves nouvelles (2e Serie). –– Annales de laSociete Entomologique de France 90: 133––155.

–– 1922b. Oenas afra L. Ses moeurs, sa larve primaire. ––Bulletin de la Societe d’Histoire naturelle de l’Afrique duNord 13: 226––236.

–– 1928a. Etudes biologiques sur diverses especes alger-iennes du genre Lydus Latr. –– Encyclopedie entomologi-que, Coleoptera (B) 3: 49––92.

–– 1928b. Cabalia rufiventris Walker. Etude biologique. ––Encyclopedie entomologique, Coleoptera (B) 3: 39––48.

–– 1934a. Le Meloe chrysocomus Miller; sa larve primaire. ––Bulletin de la Societe Royale Entomologique d’Egypte1934: 427––435.

–– 1934b. Lagorina sericea Waltl. Sa larve primarie. –– Bulletinde la Societe des Sciences naturelles du Maroc 14: 35––44.

–– 1940. Essai de classification des Meloides algeriens. –– VICongreso Internacional de Entomologia, Madrid 1935:312––338.

Kaszab, Z. 1959. Phylogenetische Beziehungen des Flugel-geaders Meloiden (Coleoptera), nebst Beschreibungneuer Gattungen und Arten. –– Acta zoologica Acade-miae scientiarum Hungaricae 5: 67––114.

–– 1969. The system of the Meloidae (Coleoptera). –– Mem-orie della Societa entomologica italiana 48: 241––248.

Lawrence, J. F. 1991. Order Coleoptera, pp. 144––298. InStehr, F. W. (ed.) Immature Insects. Vol. 2. Dubuque,Iowa (Kendal/Hunt).

MacSwain, J. W. 1956. A classification of the first instar lar-vae of the Meloidae (Coleoptera). –– University of Cali-fornia Publications in Entomology 12: 1––182.

Selander, R. B. 1990. Blister beetles of the genus Pseudo-pyrota (Coleoptera: Meloidae). –– Journal of the KansasEntomological Society 63: 46––79.

Turco, F. & Bologna, M. A. 2005. Sexual and cleaning beha-viour of Lydus trimaculatus Fabricius with remarks on thecourtship of the Lyttini (Coleoptera: Meloidae). –– Mittei-lungen aus dem Museum fur Naturkunde, Deutsche Ento-mologische Zeitschrift 52: 131––137.

Turco, F., Di Giulio, A. & M. A. Bologna, Lydina larval morphology (Coleoptera, Meloidae, Lyttini)222

# 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim http://museum-dez.wiley-vch.de