Life History of Pleotomus Pallens LEC

Psyche: A Journal of Entomology, Mar 2019

Helen Selina King

A PDF file should load here. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser.

Alternatively, you can download the file locally and open with any standalone PDF reader:

Life History of Pleotomus Pallens LEC

International Journal of The habitat of this species of the sub- light from the ventral surface of the postetribe Zampyrini is western Texas where riot segment. When fully grown the larva the mature form appears in May a month except that the color is different and the later than several species of Photinus. body is less depressed is precisely similar Both sexes are phosphorescent the % feebly to that of the commonest species of _Phoso emitting a greenish light without rays tinus larva found her% which is perfectly but sufficiently bright to betray his pres- represented in figure 431 of Packard's ence; the 9 is much more brilliant her Guide to the Study of Insects." It has light being sufficient to show not only her twelve segments exclusive of the head body but also surrounding objects for a which latter is composed of two flattened distance of several centimetres. After ovi- narrower segments the inner one forming position this light declines and the femal% the neck and both retractile within the who seems to have assumed the perfect thorax. It feeds on snails; and sheds its form for the purpose alone of laying eggs larval skin at least twice possibly oftener soon dies. She does not ied and is too before reaching maturity. Under confinehelpless to move far from the place of her ment in a pot of earth with snails for food final metamorphosis owing to the feeble it assumes the pupa state in about seven support which her disproportioned body weeks but it may attain its growth sooner receives from her feet. When creeping when at large. Both the larval moults and as she does by spasmodic efforts she touches the transformation to pupa are peribrmed objects with her palpi and moves her head by the splitting of the membrane on the from side to side. The eggs are deposited pleura through the first three segments and in one or more pits which the female makes its removal over the posterioc end of the in the soft moist earth with her abdomen, abdomen. The eggs are smooth, round, pale yel- The shield of the pupu immediately lowish, about the size of black mustard after its liberation from the larval skin, seed, and, as far as I am aware, not phos- seems to consist of two fused segments phorescent. In six weeks they produce the three following segments are narrow young larvae 4 ram. long, cinereous on and the middle one of these has a transverse dorsum, dull white on renter, and emitting depression suggesting the fusion of two - segments at that point. Following these tennae short approximate 14-jointed blare seven abdominal segments. The pec- pectinate usually folded so as to seem unitinate antennae and the wing cases are pectinate situated in front of the eyes and seen and on the propygidium the phospho- parallel with anterior edge of the prothorax rescent vesicles are visible as clear greenish their tips recurved color fuscotestaceous. yellow spots. From the terminal segment t)rothorax finely punctulate subhyaline, elare two straight processes. The pleura1 evated at its base; its sides beneath emregion antennae and feet distinguish this bracing the neck and forming a collar for pupa from those ot Photinus. The final the head when the latter is protruded: it metamorphosis takes place in six days. is broader than in the ordinary species of The 9 form assumed the pupa condition firefly, fuscotestaceous with rosy centre one week later than the %. It has two in some in others with transverse irreguwhite tubercles or small processes on the lar confluent pink spots on the posterior sides of the wing-bearing segments indi- part; the flanks beneath this part are also cating the position of the future rudiment- pink. Elytra striate, elevated at their aryelytra. The pleural region is different base, the concave humeral region erafrom that of the % and the parts of the bracing the sides of the abdomen whence mouth are not sheathed separately as in the elytra slope backward to a narrow dethe % but are as it were muzzled. An- hiscent point, leaving nearly three segments tennae and eyes are not visible; the shield visible. Wings same length as elytra, and seems to consist of two fused segments as smoke color. Feet feeble and compressed seen through the thin membrane. There same color as the body. Seven ventral are seven abdominal segments. The whole segments short the last one pointed and body is of a salmon color. This pupa ma- partly retracted within the penultimate, tures in six days and perfects as an apter- which is emarginate. ous imago with rudimentary elytra. On the last abdominal ring there is a Thus we find that under artificial man- spot on the anterior outer margin of doragement the eggs will mature sufficiently sum and venter seen in the day as of a to hatch in five weeks the larva requires deeper yellow than the surrounding parts. about seven weeks to reach the pupa stage Through this at night comes the phosphorand the latter lasts only six days the % in escence not in flashes but as two oval one instance accomplishing its cycle one spots equally evident above and below week sooner than the 9. In a few days but more feeble than in any other firefly after becoming perfect the % dies, and the known to me. The % has the same quick 9, after wandering a little, lays her eggs spasmodic motion noticed in the 9. He and dies also. feeds sparingly on the common garden Pleotomus pallens % is rare. Head snail probably on its slime, being I should covered by the prothorax. Eyes large think too feeble to be actively aggressive dark-purplish contiguous. Labial palpi though I have seen him cling to a snail visible at tip. Maxillary palpi small, shell with much persistency. Vlandibles not prominent very small. An- Pleotomus pallens 9, though apparently more abundant than the %, is yet compar- the insect consequently moves with sudden atively rare. It is of a buff or sahnon nervous action, and pauses every fewsteps. color, with eleven segments, pink on their Though there are no special phosphoresposterior margins, and overlapping. Head cent vesicles visible through the membrane, narrow, with projecting muzzle, but im- yet it emits light from the entire ventral perfect organs ofmanducation. Eyes small, surface of the three posterior segments. round, black, on sides of the head. Anten- This is very brilliant, and when less intense nae shorter than thorax, approximate, sit- posteriorly, appears diffused over the body. uated in front of the eye, pale yellow, fee- This brilliancy continues until oviposition. bly pectinate. Thorax with margin re- This 9 insect is similar to Packard?s illusflexed, subrugose. Adjoining the shield tration 428, of an apterous 9 from Madaare the rudimentary elytra, semicircular gascar, plus the aborted elytra and pectinand very small. Feet feeble, compressed; ate antennae. the body is disproportionately large, and NOTE ON NORTH AMERICAN TRYPETIDAE. BY CHARLES ROBERT OSTEN SACKEN, HEIDELBERG, GERMANY. Among a number of diptera, collected by This is a very small number, in compariMr. J. Boll in Dallas, Texas, and purchased son to that of the described N. A. Trypeta by me in Geneva a short time ago there but the most striking circumstance in conwere 25 % and 9 specimens of a Trypeta, nection with it is that among six Trypeta bearing on a label bred from galls on whose habits are known, not less than.four Ambrosia." The insect could be easily should occur in galls, and only one in the identified with T. gibba Loew, and as the heads of a composite flower. In Europe habits of this species were hitherto un- the Trypeta bred from galls form an imperknown, I deem it worth the while to put ceptible minority, and most of the species Mr. Boll?s observation on record, are obtained from the heads of composites. The gall, which is likewise in the collec- Compare, for instance, the list of 60 species tion is an oblong swelling of the stem bred by Frauenfeld (Verh. k.-k. zool.-bot. probably terminal. Gesell. Wien, 1863 p. 221-224), among The habits of the following North Amer- which only three formed galls on the stem ican Trypeta have been hitherto investi- of the plant. gated and published (the name of the dis- It would be worth while for American coverer is in parentheses) :-- entomologists to collect dry heads of comRhagoletis pomonella.- Fruit of the apple-tree posite plants in aut.umn for the purpose of Oed(aWsaplissh)pg.oilbibtaa.. GGaallll oonnASmoblriodsaigao ((0Bo.llS)..). bspreeceideisngofTtrhyepseetparetutylaflrigees wnouumlbderproofbanbelwy fEf,uurtorsettaa sdoilaidnaag.i-n-iGsa.l-lGalolnonArStoelmiidsaigao (tHrairdreinsta)t.a be obtained. (Riley). September 1879. Aspilota alba. Seeds of Vernonia (Riley). Peptides Advance s in ht p:/ w Virol og y Hindawi Publishing Corporation Hindawi Publishing Corporation ht p:/ Submit your manuscr ipts BioMed Hindawi Publishing Corporation ht p:/ Research International Stem Cells International Hindawi Publishing Corporation ht p:/ Zoology International Journal of Journal of Signal Hindawi Publishing Corporation ht p:/ Transduction Research International Hindawi Publishing Corporation ht p:/ Anatomy Research International Research International Advances in Bioinformatics Hindawi Publishing Corporation ht p:/ Hindawi Publishing Corporation ht p:/ Enzyme Research International Journal of Journal of International Journal of Genomics Hindawi Publishing Corporation ht p:/ Journal of Nucleic Acids The Scientiifc World Journal

This is a preview of a remote PDF:

Helen Selina King. Life History of Pleotomus Pallens LEC, Psyche: A Journal of Entomology, DOI: 10.1155/1880/21983