Camelobaetidius (Ephemeroptera: Baetidae) in Indiana and Iowa: new species and range extensionq

7 Pages·1994·1.9 MB·

by  W P Mccafferty

PROC. ENTOMOL. SOC. WASH.
96(1). 1994, pp. 37-43
CAMELOBAETIDWS (EPHEMEROPTERA: BAETIDAE) IN INDIANA
AND IOWA: NEW SPECIES AND RANGE EXTENSION
W. P. McCafferty and T. H. Klubertanz
(WPM) Department ofEntomology, PurdueUniversity, West Lafayette, Indiana47907;
(THK) Department ofEntomology, Iowa State University, Ames, Iowa 5001 1.
Abstract—Camelobaetidius waltzi McCafferty, n. sp.. is described from larvae taken in
the lower Wabash River of southwestern Indiana and the lower Des Moines River of
southeastern Iowa. It differs from other species of Camelobaetidius primarily in having
a unique combination ofa medially pointed second segment ofthe labial palps and six
or seven claw denticles. The new species significantly extends the known range of this
mainly southwestern and Neotropical genus into the humid midwestem United States.
Relationships among species ofCamelobaetidius remain unknown.
Key Words: Ephemeroptera, Baetidae. Camelobaetidius, new species, distribution
The Western Hemisphere genus Came- species of Camelobaetidius originally de-
lobaetidius Demoulin is striking among the scribedby Demoulin (1966), and fourmore
Baetidae because ofthe remarkable spatu- speciessubsequentlydescribedbyAllenand
late and multidenticulate tarsal claws pos- Chao(1978)and Allen and Murvosh (1987)
sessed by the larvae (e.g. Fig. 7). Such may- include all nominal species heretofore rec-
flies were first noted from Brazil by Traver ognized in Camelobaetidius.
944)as Baetine No. and more regularly The genus has been known from western
(1 1,
in the 1950"s and 1960's by workers col- North America as far east as far western
lecting mayflies in California, Utah, and Kansas (Liechti 1982) and central Texas
Wyoming. While still uncommonly taken (Lugo-Ortiz and McCafferty 1993) and as
except at specific riversites where they may farnorthasSaskatchewan (Lehmkuhl 1976),
beabundant (e.g. the Virgin River in south- from throughout Mesoamerica, and from
em Utah), the genus has proven to be one South America as far south as Uruguay and
of the most commonly taken baetids in a central Argentina. McCafferty et al. (1992)
varietyofstreamsin Texas(McCaffertyand hypothesized that the most recent center of
Davis 1992). dispersal ofCamelobaetidius was Neotrop-
The single major study of Camelobaeti- ical. Traver and Edmunds (1968) had con-
dius was made by Traver and Edmunds cluded earlier that the taxon was of Neo-
(1968), wherein 13 species, considered at tropical origin. Since no phylogenetic study
that time under the name Dactytobaetis of the species of the genus has been con-
Traver and Edmunds, were treated and ducted, it is not known whether species re-
compared. McCafferty and Wahz (1990) lationships will corroborate Neotropical af-
synonymized Dactylobaetis with Camelo- finities orindicate towhatextent vicariance
baetidius and discussed the generic classi- and dispersal have influenced present spe-
fication. The 13 species originallydescribed cies distributions.
by Traver and Edmunds (1968), the type In July of 1977, the first author and A.
PROCEEDINGS OFTHE ENTOMOLOGICALSOCIETY OF WASHINGTON
38
V. Provonsha of Purdue University unex- apically (somewhat more oblique in youn-
pectedlycollected a maturelarval specimen gerlarvae), withdenticlesnearlycompletely
ofCamelobaetidiusfrom the Wabash River fused and six in number on each mandible;
in southwestern Indiana near New Har- prostheca well developed on both mandi-
mony, an area ofsome taxonomic note be- bles, serrate apically on right mandible and
cause Thomas Say had described many of with variably developed tuft medial to it
his species of aquatic insects and mussels (Fig. 2); prostheca greatly enlarged on left
from there. Upon sorting samples, it was mandible and with acute apicomedial pro-
clear that this larva represented an unusual cess (Fig. 3); thumblike projection adjacent
new species in the genus. Additional spec- to molar region of left mandible well de-
imens could not be found on subsequent veloped and robust (Fig. 3); on right man-
collecting trips to the same area, and the dible (Fig. 2) molar region in same plane
fact that only one specimen was available with apices ofbody ofmandible, and with
belated publication ofthe new species. small branched seta at medial margin of
In August of 1991, the secondauthorcol- molar region. Maxillae (Fig. 4) with basal
lected, also unexpectedly, a series ofyoung and apical portionsofgalealacinia subequal
larvae of Camelobaetidius from the Des in length; palpi relatively short and thick
Moines River at Farmington, Iowa, in the with second segment slightly narrower than
extreme southeastern area of that state. first. Labium (Fig. 5) ofshort, robust vari-
Comparisons with the Indiana larva showed ety; second segment of palpi distinct with
them to be the same species. More mature convex apicomedial margin and concave
Iowalarvaeweretaken fromtheDes Moines basomedial margin meeting at medial an-
River in the same general area in 1992. A gularpoint; medialpointsometimesslightly
description and discussion ofthis new spe- more produced than shown in Fig. 5.
cies follows. The terminology applied gen- Thorax: Pronotum and mesonotum var-
erally follows that used by Traver and Ed- iously suffused with light to medium brown
munds (1968). patterning (darkness increasing with age in
most individuals). Coxal gills absent. Fore-
Camelobaetidius waltzi McCafferty, legsslightly longerthan hindlegs. Femurand
New Species
tibia offorelegs subequal in length; forefe-
Figs. 1-10 mora without spines on anterior surface;
Larva (in alcohol).—Mature length ex- apices offoretibiae with one to five robust
mm
cluding caudal filaments: 6.0 (male) to spines (Fig. 6); foretarsi with five to eight
mm
6.3 (female). short spines, two bristlelike long spines ar-
Head: Vertex with paired light brown ranged as in Fig. 6 (one bristlelike spine
longitudinal markings variously developed; subapical and one at about one-fifth length
frons usually with broad inverted V-shaped of tarsus from apices), and up to six ad-
brown marking between lateral ocelli. An- ditional minute spines along concave mar-
tennae nearly white. Labrum (Fig. 1) with gin. Spatulate tarsal claws (Fig. 7) with six
submarginal row of elongate spines con- tosevendenticles(numbersometimesvary-
sisting of two relatively widely separated ing from right to left legs) and with sensory
central spines, no intermediary spines, and setaarisingfromclawtipandextendingme-
six to eight lateral spines on each side ar- dioapically to about same distance as claw
ranged incurvedlinewiththreeorfourmost tip.
lateral ones set offslightly from line ofme- Abdomen: Color pattern (Figs. 8-10)
dial ones; no folds or ridges apparent on more-or-less consistent with other species
labral surface. Mandibles as in Figs. 2, 3; ofgenus, with tergal markings consisting of
incisors fused and more-or-less truncate pairsofsubanterolateraltosublateralorlat-
VOLUME NUMBER 39
96, 1
Figs. 1-7. Camelobaetidius wahzi. holotypelarva. 1. labrum; 2. rightmandible; 3. leftmandible; 4. maxilla;
5, labium; 6, partial foreleg; 7, foretarsal claw.
40 PROCEEDINGS OFTHE ENTOMOLOGICAL SOCIETY OFWASHINGTON
8 10
Figs.8-10. Camelobaelidiuswahzi.larva.8,dorsalabdomen,holotype;9.abdominaltergalpatternvariation;
10. abdominal tergal pattern variation.
eral concentinc markings and submedial gills not marginally sclerotized in some
longitudinal markings,andterga 8-10much young larvae.
lighterthan otherterga; degree oftergal pig- Holotype.—Mature female larva, Indi-
mentationgenerally increasingwith age(Fig. ana: PoseyCo.. Wabash R. atOld Dam near
8); short black oblique submarginal marks New Harmony. VII-20-1977. W. P. Mc-
on posterior margin of terga 4-8: antero- Cafferty and A. V. Provonsha, mouthparts
lateral comers ofterga not dark margined: and foreleg slide mounted, other parts fluid
some individuals with more marked ab- preserved, deposited in the Purdue Ento-
dominal pattern as in Fig. 10, having rela- mological Research Collection (PERC),
tively lightertergum 5 and relatively darker West Lafayette, Indiana.
terga 6-7: sterna unmarked except some in- Paratypes.—Eight matureandnearlyma-
dividuals with brown transverse penciling ture larvae, Iowa, Van Buren Co., Des
atmediumthirdofanteriormarginofsterna Moines R. at Lacy Keosauqua State Park,
2-6 or 2-7 (more developed on more an- VIII-29-1992, T. H. KJubertanz, si.x with
terior sterna). Terga 3-7 with very minute same deposition as holotype. two deposited
single spine at posterolateral comers (best in United States National Museum. Wash-
seen on tergum four). Gills (Fig. 8) with ington, D.C
.
moderately sclerotized anterior and poste- Additional material examined.—Nine-
rior margins (more sclerotized anteriorly). teen middle to lateinstarlarvae (some parts
VOLUME 96, NUMBER 1 41
onslides), Iowa,Van BurenCo., DesMoines out the West from Arizona to Saskatche-
R. at Farmington, VIII-19-1991, T. H. wan. The new species shares relatively few
Klubertanz; seven larvae and two female characteristics with C. warreni.
subimagos, Iowa, Van Buren Co., Des Our study of individual and age vari-
Moines R. at Lacy Keosauqua State Park, ability indicated that certain characteristics
VIII-29-1992, T. H. Klubertanz. deposited used for species discrimination by Traver
in PERC. and Edmunds (1968) may not be valid.
Etymology.—This species is named after These include color patterns ofthe abdom-
R. D. Waltz in recognition ofhis numerous mal terga, condition of the incisors of the
contributions to our knowledge ofthe clas- mandibles, and thickness of the maxillary
sification and relationships within the fam- palps, all of which we found to be highly
C
ily Baetidae. variable in waltzi. mainly due to age dif-
Discussion.—Couplet 2 ofthe key to Ca- ferencesin larvae. Thenumberofclawden-
melobactidius species provided by Traver ticles increases with age, and this may ac-
and Edmunds (1968) divides species into count for the range of numbers described
those that have claws with five to 17 den- for many ofthe speciesthat Traverand Ed-
ticles and rounded second segments of the munds (1968) studied. Although no indi-
C
labial palps and those that have claws with vidualsof waltzi had coxalgills, wewould
20 to 40 denticles and second segments of caution that it may be possible for species
the labial palpsthat aretruncate orpointed. ofCamelobaetidiiis to be individually vari-
Camelobaetidiiis waltzi would not fit either ableinthisrespect as, forexample, hasbeen
ofthesegroupingsbecause ithastheunique, found in the genus Baetodes. Characters of
and diagnostic, combination of a small potentialvalueinspeciesdiscriminationthat
numberofclawdenticlesandadistinctively havenot been used previously include form
pointed second segment ofthe labial palps. oftheprosthecaandthepresenceorabsence
After considering all apparent species ofa complex seta on the medial edge ofthe
specific larval characteristics, neither phe- molars of the right mandible. Traver and
netic nor phylogenetic relationships of C. Edmunds (1968) did not mention or figure
waltzi could be determined with any con- the sensory seta found at the tip ofthe claw
fidence. However, the labial palps of the (Fig. 7)ortheterminallyhookedapicalsetae
new species are most similar to those of oftheparaglossae(Fig. 5). Ourexamination
Neotropical species, particularly C. penai of larvae of all species available to us in-
(Traverand Edmunds) from Argentina and dicatesthatthesecharacteristicsaregeneric.
C. anubis(Traverand Edmunds) from Bra- Theareaswherethenewspecieswasfound
zil. If the pointed second palpal segment in Indiana and Iowa are only a little over
proves to be apomorphic, a phylogenetic 300milesapart. Allknownlarvaeweretaken
relationship with these species may exist. atlargeriversites—eithertheWabash River
The new species shares labral and mandib- relatively near its confluence with the Ohio
ularcharacteristics,thesmallnumberofclaw River or the Des Moines River very near
denticles, and a general lack of pigmented its confluence with the Mississippi River.
tracheation in the abdominal gills with the Although the lowerWabash Riverbasically
North American C. Diexicaniis (Traver and possesses a silt/clay substrate, the type lo-
Edmunds). The latter species is common cality there consists ofa natural rocky out-
throughout Texas and Mexico. Camelohae- crop giving rise to a small fall that becomes
iidius warreni (Traver and Edmunds) is the visibleand accessible when the river is very
onlyothercommon speciescurrently known low. The exact microhabitat of C. waltzi
in North America, where it occurs through- larvae at this site was not recorded at the
42 PROCEEDINGS OFTHE ENTOMOLOGICAL SOCIETY OFWASHINGTON
timeofcollectionbecauseitwasnotrealized weakening the previous inferential evi-
Camelobaetidiuswasbeingtaken until after dence. On the other hand, it is becoming
the fact. apparent that many ofthe other described
Larvae were taken on the Des Moines North American species of Camelobaeti-
Riverattwositesin 15-130cmdepth, where dius may fall into synonymy (see Mc-
either small sized stones or concrete rubble Caflferty and Waltz 1990), and thus, the ge-
(13-26 cm diameter)werepresent. Thema- nus may be much more diverse in the
jority ofsubstrate ofthe river in this region Neotropics. Thisalso is provingto be a pre-
consists ofsilt and mud. Larvae were found dictable pattern for most Neotropical may-
crawling among filamentous algal mats as- fly groups (McCafferty et al. 1992).
sociated with the stones and rubble. The
only other species taken in abundance with Acknowledgments
C. waltzi was Baetis longipalpus Morihara We thank A. V. Provonsha for preparing
and McCafferty. Baetis longipalpus, how-
the line drawings, and R. D. Waltz for his
ever, occurred on larger stones and drift-
help with this study. This paper has been
wood. Otherspeciesofmayfliestakeneither
assigned Purdue Experiment Station Jour-
as larvae or adults at the general site in- nal Number 13721.
cluded Baetis intercalaris McDunnough,
Caenishilaris(Say), Centroptilum sp., Hep-
tagenia flavescens (Walsh), Hexagenia lim- Literature Cited
bata Serv'ille, Isonychia sicca (Walsh), Leii- Allen, R. K. and S. M. Chao. 1978. Mayflies ofthe
crocuta sp., Stenonema mexicanuin Southwest: New species and records ofDactylo-
(Ulmer), and 5. tennirtatuin (Walsh). baetis(Ephemeroptera:Baetidae). Pan-PacificEn-
JulTyh,e19s7p7e,cfirmoemntohfeDW.abwaalsthziRitvaekrenwaosnre2l0- .Allentf.orRmoo.mlKot.ghieasnstdou5C4l:Mhw.3e0s0Mt-ue3rm0v4oL.'snhi.ted19St8a7t.esNaenwdnBoaretthiedrane
atively mature; those taken on 19 August, Mexico(Ephemeroptera: Insecta).withnotes. Ca-
1991, from the Des Moines River were nadian Entomologist 76: 425—433.
mainly middle instar larvae with a few of Demoulin, G. 1966. Contribution a I'etude des
them more mature: and several of those Ephemeropteres du Surinam. Instilut Royal des
Sciences Naturelles de Belgique Bulletin 42(37):
taken on 29 August, 1992, from the Des
1-22.
Moines Riverwere mature. Someofthelat- Lehmkuhl. D. M. 1976. Mayflies. Blue Jay 34: 70-
terunsuccessfullyattemptedtoemergewhile 81.
being held in temporary containers. In ad- Liechli. P. M. 1982. Fiveadditional Ephemeroptera
dition, many baetid subimagos were seen genera from Kansas. Technical Publication ofthe
Stale Biological Survey ofKansas 12: 13-16.
along the shore at the collecting site, but Lugo-Ortiz. C. R. and W. P. McCatferty. 1993. The
thesecould notbecorrelatedpositivelywith mayflies(Ephemeroptera)ofTexasand theirbio-
the C. waltzi larvae. geographic affinities. In Corkum, L. and J. Cibo-
McCaffertyet al. (1992) hypothesized that rowski. eds.. Proceedings ofthe Seventh Interna-
Camelobaetidius had a most recent center tional Conference on Ephemeroptera. Sandhill
Crane Press. Gainesville. (In press.)
ofdispersal in the Neotropics because the McCaflerty, W. P. and J. R. Davis. 1992. New and
genus demonstrated an arid-favored distri- additional records of small minnow mayflies
bution in North America. In the absence of (Ephemeroptera: Baetidae) from Texas. Entomo-
cladistic data for species, this at least fit the logical News 103: 199-209.
pattern shown by most Neotropical mayfly McCafferty, W. P., R. W. Flowers, and R. D. Waltz.
1992. The biogeography ofMesoamerican may-
groups in North America. The new species
flies, pp. 173-193. In Darwin, S. P. and A. L.
described herein clearly has a humid dis- Weldon,eds.,BiogeographyofMesoamerica:Pro-
tribution pattern in the Midwest, perhaps ceedings ofa Symposium. Tulane Studies in Zo-
VOLUME 96, NUMBER 1 43
ologyand Botany, Supplemental Publication No. Traver,J. R. 1944. NotesonBrazilianmayflies. Bol-
1, New Orleans. etim do Museu Nacional, Zoologia 22: 2-53.
McCafl'erty, W. P. and R. D. Waltz. 1990. Revision- Traver,J.R.andG.F.Edmunds,Jr. 1968. Arevision
ary synopsis ofthe Baetidae (Ephemeroptera) of of the Baetidae with spatulate-clawed nymphs
North and Middle America. Transactions ofthe (Ephemeroptera). Pacific Insects 10: 629-677.
Amencan Entomological Society 1 16: 769-799.