John W. Beardsley.
A New Fossil Scale Insect (Homoptera: Coccoidea) from Canadian Amber.
Psyche 76:270-279, 1969.

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A NEW FOSSIL SCALE INSECT
(HOMOPTERA: COCCOIDEA)
FROM CANADIAN AMBER
BY JOHN W. BEARDSLEY
University of Hawaii, Honolulu1*
Oligocene and Miocene ambers from the Baltic area and from Mexico have yielded more than 100 known specimens of fossil Coc- coidea. However, insofar as they can be identified, these all appear to belong to extant genera. The only previously described Mesozoic coccid fossil, Mesococcus aslatica Becker-Migdisova ( 1959), is an impression, said to represent a wingless female or nymph, from an Upper Triassic deposit at Issik-Kul, Kirghiz, SSR, Soviet Union. From the published description and figure of that specimen, its as- signment to the Coccoidea seems to be based upon rather inconclusive evidence as important structures, such as the antennae and mouth- parts, are not preserved.
The specimen described here is preserved in amber from Cedar Lake, Manitoba. This amber is almost certainly of Upper Cretaceous age (Carpenter, et al, 1937; Richards, 1966)~~ The specimen is unquestionably an adult male coccid, and is in a relatively good state of reservation. The body and its appendages appear to be almost entirely intact, and the specimen is not obscured by any large external air bubbles, as in some Baltic amber coccids which I have examined. Parts of the specimen are somewhat distorted due to shriveling of the membranous portions of the integument. The venter of the head apparently is split or torn behind the ventromedial plate, and flap-like shreds of membranous integument extend beneath the head in this region. A pronounced flaw plane roughly perpendicular to the insect's body, intersects the specimen on the posterior part of dorsum of the thorax and partially obscures certain morphological details in that region. The entire venter of the insect is unobstructed, however. The left forewing extends posteriously at a slight angle to the body, and most of the details of the wing are clearly discern- Published with the approval of the Director of the Hawaii Agricultural Experiment Station as Journal Series No. 1116. Manuscript received by the editor June 2, 1969. 'This research was supported in part by National Science Grant GB-4289; Spencer W. Brown, Principal Investigator. 'I wish to thank Dr. F. M. Carpenter, Harvard University, for providing the opportunity to study this fossil coccid.



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19691 Beardsley - Fossil Scale Insect 27 1 ible. The right forewing lies directly over the abdomen making details of the dorsum of the metathorax and abdomen difficult to see. The hind wings, which in male Coccoidea are absent or reduced to very small, linear or club-like hamulohalteres, are indistinguishable in this specimen, although possibly present but obscured by the flaw plane. The comparative external morphology of adult male Coccoidea has been the subject of considerable research during recent years (Theron, 1958, 1960 ; Beardsley, 1968). Most of this work has involved study of the comparative morphology of the cephalic and thoracic sclerites in specimens which have been properly cleared and stained. Fortu- nately, the Cedar Lake specimen is well enough preserved that it has been possible to identify most of the integumental sclerites, thereby permitting comparison with the known adult males of extant Coc- coidea. In the description which follows the terms used are largely those introduced by Theron (1958) which have been accepted, with slight modifications, by other students of male coccids. The accompanying figures necessarily are somewhat diagrammatic. Because of distortion due to shriveling and the obscuring of certain structures by the dorsal flaw plane, it was necessary to observe all surfaces of the specimen from many angles, using different lens and light combinations, to properly delimit the integumental sclerites and other structures. It is quite possible that weakly developed sclerites which might have been seen had it been possible to clear and stain the specimen, have been overlooked.
Electrococcus, new genus
Coccoidea, presumably of the family Margarodidae (sens. lat.) . Adult male characterized by small size, well-developed cephalic and thoracic sclerites, ten segmented antennae with the pedicel conspic- uously enlarged, three pairs of moderately elongate slender legs and a pair of well-developed mesothoracic wings. Head well defined, separated from thorax by a distinctly constricted neck region. Ocular sclerites well developed, each bearing an anterior dorsoventral row of simple eyes, plus a single larval eye (stemma) laterally behind anterior row. With well-defined dorsomedial and ventromedial scler- ites. Posterior margin of dorsum of head with a postoccipital ridge. Functional mouthparts absent ; structure of tentorium not determined. Mesothorax strongly sclerotized; with a convex prescutum sep- arated from lateral margins of thorax by anteriolateral extensions of the scutum. Scutum without a mesa1 membranous area. Scutel- lum small, somewhat convex, approximately trapazoidal in shape, apparently separated from inesopostnotum by a moderately wide



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Psyche
[September
stn,
3
Fig. 1. Electrococcus canadensis n. sp., lateral aspect of head and thorax. Fig. 2. Dorsal aspect of head and thorax. Fig. 3. Ventral aspect of head and prothorax.




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19 691 Beardsley - Fossil Scale Insect 27 3 membranous area. Mesosternum elongate, convex below, and rather strongly displaced posteriorly in relation to the tergites so that the mesopleurites are noticeably more inclined than in most other male Coccoidea. Sclerites of pro- and metathorax greatly reduced, as in itremes
other male Coccoidea. Two pairs of thoracic spiracular per' present.
Abdomen relatively elongate, slender; with eight discernible pre- genital segments which become progressively narrower posteriorly. Apex of abdomen bearing a moderately elongate, apically acute, sclerotized penial sheath with a slit-like ventral opening. Structure of aedeagus not determined. Dorsal abdominal tubular duct clusters or lateral pore pockets apparently absent. Abdominal spiracles not discernible.
Type of genus: Electrococcus canadensis, n. sp. Electrococcus canadensis, n. sp. (figures 1-8) Length of specimen, excluding antennae 1.3 mm; length of fore- wing 0.9 mm.
Head distinctly separated from thorax by a markedly constricted neck region; lateral areas of epicraniurn occupied by e air of large ocular sclerites (0s)) each bearing an arcuate dorsoventral row of 5 simple eyes (se) anteriorly plus a single smaller larval eye (le) or stemma laterally; posterior margin of ocular sclerite thickened to form a postocular ridge (pocr), anterior margin of ocular sclerite slightly thickened above and below articulation point of antenna1 scape. Ocular sclerites broadly separated dorsally ; dorsum of head with a definite dorsomedial sclerite (dmep) the anterior portion of which is strongly sclerotized the posterior portion much less distinctly so; posterior margin of doi-somedial sclerite marked by a thickened postoccipital ridge (pos) which does not extend laterally to the ocular sclerites. Dorsomedial plate narrowed anteriorly, extending ventrally between antennae and onto venter of head as a narrow midcranial ridge (mcr), as far as the anterior margin of the ven- tromedial plate (vmep) below. Ventromedial plate approximately in form of equilateral triangle. A narrow bar-like median longitudinal sclerite of unknown relationship (possibly a cranial apophysis) on posterior portion of venter of head behind torn area. Antennae (fig. 4) about 0.54 mm. long; scape (sc) largely membranous except for longitidinal ridge-like thickening on inner face; pedicel and flagellar segments strongly sclerotized, pedicel (pd) large, trumpet- shaped; flagellar segments bearing a few scattered slender setae, and



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Psyche
[September
Fig. 4. Right antenna.
Fig. 5. Left forewing. Fig. 6. Metathoracic leg. Fig. 7. Ventral aspect of posterior abdominal segments and penial sheath. Fig. 8. Venter of metathorax.




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19691 BeardsZey - Fossil Scale Insect 275 small
dash-like reflective areas which may be sites of very short setae, or sensoria. Apical segment with 3 curved thickened digitiform setae and four long, slender, apically capitate setae. Prothorax largely membranous; dorsum with a of small trans-
verse postnatal sclerites (pn) with weak lateral anterior extension in- dicated ; pronotal ridge apparently not developed. Propleural sclerites well defined; consisting of the propleural ridge (plrl) and a elongate cervical sclerite (cv) ; these apparently not intimately fused at junc- ture. Anterior end of cervical sclerite apparently articulating with base of postocular ridge. Small sclerotized prothoracic spiracular peritreme ( ptrl ) present in membranous area between forecoxa (cxl) and mesepisternum. Prosternite (stn, ) well defined, narrow, elongate ; anterior portion expanded into a sinall) nearly quadrate) less strongly sclerotized plate; posterior apex shaIlowIy incised medially. Prealase ( pra) narrow, strongly reflexed, arising from anterio- lateral extension of scutum, possibly extending as a narrow thickened band along anterior border of scutal extension to sides of scutum; no evidence of separate triangular plate at apex of ~realai-e. Tegula (t) relatively lai-ge and elongate. Basalare sclerite (ba) large and con- spicuous; small subalare (sa) discernible in membranous area just below wing base. Mesopostnotum (pn2), except for right side, largely obscured by flaw plane in type specimen. Postalare (antero- lateral a,rm of mesopostnotum) (pa) extending to base of pleural wing process (pwp) . ilfe~opleural ridge (ply2) extending almost horizontally forward from base of mesocoxa to presumed site of mesopleural apophysis just below base of pleural wing process. Mesepisternum (eps?) well developed, with a large, oval, somewhat convex disc area dorsally; anterior part of episternum below disc weakly sclerotized ; anterior margin marked by a narrow subepisternal ridge (ser) . A narrow? well-defined lateropleurite (lp) present at base of episternum, apparentlv separated from it bv a posterior ex- tension of the subepisternal ridge. A snd triangular sclerite, appar- ently the mesothoracic spiraculas peritreme (ptr2), behind base of mesocoxa. Mesobasisternite (stn2) large, strongly sclerotized, convex, longer than wide; apparently not divided by 2 median longitudinal ridge. A pair of small, narrow, sublaterzl sclerites immediately behind basisternite may represent a mesospinasternite. Metanotum not discernible in type speci~nen due to intersecting flaw plane. Metapleural ridge (plr3) elongate, narrow, strongly inclined, extending anteriorly from base of hind coxa to margin of flaw plane. Hamulohalteres, if present, not discernible. Metepimeron



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276 Psyche
[September
(epm) present, consisting of a narrow poste~iorly directed postcoxal ridge and small attached sclerotized patch. A very short precoxal ridge also discernible at base of metapleural ridge. A small trans- verse mesal metasternite (stn3) present (fig. 8) ; an indefinite dark area on its posterior margin may be the metasternal furca. A pair of poorly defined) narrow) sclerotized patches) on either side of the mesal metasternite) proba.bly represent detached portions of that sclerite) similar to those of SieingeZia (Theron, 1958). Forewings (fig. 5) similar to those of modern male Coccoidea. Discernible vennation includes only anterior radius vein (r) extend- ing parallel to anterior margin, nearly to apex of wing) and media (m) extending approximately parallel to posterior margin) nearly to apex. A faint ridge-like thickening present just anterior and paral- lel to r and just behind and parallel to m. Wing surface with nu- merous fine) weakly developed fold lines) similar to, but less clearly defined than in Matsucoccus males ( Beardsley) 1968). Legs (fig, 6) moderately long and slender; tibiae each with one or two conspic- uous apical setae ; tarsi apparently one-segmented ; tarsal claws long) slender.
Abdomen dorsoventrally flattened) apparently largely membranous) except for venter of segments 3 to 8 which appear somewhat sclero- tized. No dorsal or lateral tail-forming clusters seen. Penial sheath (fig. 7) apparently sclerotized dorsally only in area behind presumed site of anal opening. Ventral portion of sheath well sclesotized, apparently with a basal ridge and a slit-like longitudinal aperture; poorly defined dark area beyond apex of sheath possibly remains of aedeagus or endophallus.
The type specimen is in the Museum of Comparative Zoology) Harvard University ( MCZ # 6623) .
RELATIONSHIP OF ELECTROCO~~US
TO EXTANT COCCOIDEA
Two major subdivisions of the Coccoidea are recognized by most coccid taxonomists ; the more primitive archeococcids) (usualIy lim- ited to the families Margarodidae and Ortheziidae) and the more specialized neococcids containing the remaining 10 or 12 generally recognized families (see Borchsenius) I 957). Among extant forms the morphologically least specialized adult males are those of the Ortheziidae and such margarodid subfamilies as the Matsucoccinae and Margarodinae ( Beardsley, I 968).
The Electrococcus canadensis male exhibits a much greater degree of morphological specialization than do those of the more primitive



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Table I. Morphological features of Electrococcus compared with other male Coccoidea with eyes in dorsoventral rows. Electrococcus Pityococcus Steingelia Phenacoleachio Puto Kermes COCCUJ Pedicel enlarged
Ocular sclerites not
contiguous ventrally
Ventromedial plate
present
Pronotal ridge present
Scutum without mesa1
membranous area
Mesosternum undivided
Thorax strongly slanted
Tail-forming pore
clusters absent
Penial sheath bifid
apically
Abdomen evenly tapered




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278 Psyche [September
living archeococcids. Specialized features of the Elec~rococcus male include: I ) reduction of the compound eye to a single dorsoventral row of ommatidia; 2) the strong forward inclination of the thorax; 3) the development of broad anterior extensions of the scutum which enclose the prescutum laterallv; 4) the absenc~ of dorsal abdominal tubular duct clusters; and 5) s~nall size. 'The presence of a dorsoventral row of siinpJe eyes in adult male Coccoidea is generally interpreted as stage of reduction intermediate between the complete compound eye ty~ical of most male archeococ- cids and the isolated dorsal and ventral simple eyes which are the last i-emaining vestiges of the compound eye in the majority of male neococcids. Among extant Coccoidea, males of six well differentiated groups (families or subfamilies) have eye3 of same general type of Electrococcus. Of these t w ~ are specialized margarodids ; Steingelia ( S teingelinae) and Pityococcus ( Pityococcinae) (Theron, I 958 ; Beardsley) unpublished). Two additional groups; Puto (Putoidae) and Phenmoleachia (Phenacoleachiidae) are morphologically and cytologica~ly primitive neococcids (Theron, I 960 ; Beardsley, I 962 ; Brown and Cleveland, 1968)~ while the two remaining groups) Kernzes (Kermidae) and some genera of the family Coccidae (Gil- iomee) 1967) ) are somewhat more specialized neococcids. In Table I, certain morphological features of the EZectrococcus male are compared with those of other groups having eyes in dorso- ventral rows. This table is based upon direct comparison of speci- mens in all groups, as well as on published information. Of the groups compared) only males of Phenacoleachia (Theron, 19621, Steingelia (Theron, 1958) and the Coccidae (Giliomee, 1967) have been described in adequate detail. The evidence suggests that the Electrococcus male is more similar to males of Pityococcus than to any of the others.
The structure of the cephalic and thoracic sclerites in Electrococcus indicates that it is the male of a specialized ai-cheococcid or a very primitive neococcid. The several points of similarity between this specimen and males of Pitj~~coccus have led me to conclude that Elcctroc~ccus is probably a specialized type of margarodid) possibly related to modern Pityococcinae.
The relatively high degree of morphological specialization in the Electrococcus male indicates that at least the archeococcids had al- ready undergone considerable divergence before the end of the Cre- taceous, and suggests that the original divergence of the ancestors of modern Coccoidea and Aphidoidea probably occurred relatively early in the Cretaceous, or even before.



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19691 BemdsZey - Fossil Scale Insect 279 LITERATURE CITED
BEARDSLEY, J. W.
1962. Descriptions and notes on male mealybugs (Hornoptera: Pseu- dococcidae). Proc. Hawaiian Entomol. SOC. 18 : 81-98, 1968. External morphology of the adult male of Ma~sucoccus bisetosus. Ann, Entomol. SOC. Amer. 61: 1449-1459.
BECKER-MIGDISOVA, E. E.
1959. Some new representatives of the Sternorhyncha from the Permian and Mesozoic of the U.S.S.R. (in Russian; translation by U. S.
Department Agriculture, Ent. Research Branch). Materialy K. Osnovam Paleontologii, 3 : 115-116.
BORCHSENIUS, N, S.
1958, On the evolution and phylogenetic interrelationships of the Coc- coidea (Insecta Homoptera). (in Russian; translation by U. S. Dept. Agric. Ent, Res. Branch), 2001. Zhur. 37: 765-80. BROWN, S, W. and C. CLEVELAND
1968. Meiosis in the male of Puto albicans (Coccoidea: Homoptera) Chromosoma 24: 210-232.
CARPENTER, F. M. ET AL
1937. Insects and arachnids from Canadian amber. Univ. Toronto Studies, Geol. Ser. 40: pp. 7-62.
GILIOMEE, J. H.
1967. Morphology and taxonomy of adult males of the family Coccidae (Homoptera: Coccoidea). Bul. British Mus. (Natur. Hist.) Entomol. suppl. 7. 168 pp.
MCALPINE, J. F, AND J. E, H. MARTIN
1969. Canadian Amber - A paleontologicaI treasure chest. Can. Ent. 101 : 819-838.
RICHARDS, W, R.
1966. Systematics of fossil aphids from Canadian Amber (Homoptera: Aphididae). Can. Ent. 98 : 746-760.
THERON, J. G.
1958. Comparative studies on the morphology of male scale insects (Hemiptera: Coccoidea). 71 pp + 42 fig.
1962. Structure and relationships of the male of Phenacoleachia zealandica (Maskell) (Hemiptera: Coccoidea). Proc. Royal En- tomol. SOC. London Ser. A 37: 145-53.




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