Three paratypes of Nothobrya schubarti Arl , 1961 were examined in connection with
a forthcoming description of a new genus of Entomobryidae. Some of the features observed by Arl 
in 1961, appeared similar to those of the new genus. These included: small size, color, the presence
of PAO, a falciform mucro, the trochanteral organ and the body setae. Observation of a specimen with
SEM allowed us to see the PAO and the other characteristics described by Arl  in more detail, but
other features not described by him were seen which indicate that the genus belongs in subfamily
Orchesellinae

Baquero-Martin, E. (Enrique)

Christiansen, K. (Kenneth)

Jordana, R. (Rafael)

Dadun, University of Navarra

REDESCRIPTION OF NOTHOBRYA SCHUBARTIARL, 1961 (COLLEMBOLA, ENTOMOBRYOMORPHA)1Enrique Baquero2, Rafael Jordana2, and Kenneth Christiansen3ABSTRACT: Three paratypes of Nothobrya schubarti Arl, 1961 were examined in connection witha forthcoming  description of a new genus of Entomobryidae. Some of the features observed by Arlin 1961, appeared similar to those of the new genus. These included: small size, color, the presenceof PAO, a falciform mucro, the trochanteral organ and the body setae. Observation of a specimen withSEM allowed us to see the PAO and the other characteristics described by Arl in more detail, butother features not described by him were seen which indicate that the genus belongs in subfamilyOrchesellinae.KEY WORDS: Collembola, Nothobrya, Orchesellinae, Entomobryomorpha.Arl (1961) described the genus Nothobrya of the family Entomobryidae fromBrazil which was characterized by a lack of scales, presence of a postantennalorgan, and a falcate mucro. Although the genus was placed with other Ento-mobryidae, its taxonomic placement  has remained unclear and no subsequentrecords of the genus have been made. Barra (1999) examined type specimens ofNothobrya and clearly showed it to be distinct from his genus Capbrya. Due tothe kindness of Dr. Cleide de Mendona (Museu Nacional, Departamento deEntomologia, Universidade Federal do Rio de Janeiro, Brazil) we were able toexamine three paratypes of this unusual species and clearly establish that thegenus belongs in the subfamily Orchesellinae of the family Entomobryidae.METHODSThe specimens were preserved in ethyl alcohol, apparently in good condition(Fig. 1), but they were very fragile. One specimen was mounted on slide usingHoyerÕs medium; another, without cleaning due to its fragility, was dehydratedusing an ethanol series followed by critical-point drying in CO2, mounted on analuminium SEM stub, and coated in Argon atmosphere with 16 nm of gold in anEmitech K550 sputter-coater. SEM observations were made in a Zeiss DSM940A with a new digital image capture (Point Electronic GmbH, Germany). Al-though the animal is much wrinkled, the photographs have been included in thispaper since they are informative. Some characteristics observed under both thelight microscope and SEM are added to ArlÕs 1961 description.Vol. 115, No. 1, January & February 2004 31______________________________1 Received on May 19, 2004. Accepted on May 21, 2004.2 Department of Zoology and Ecology, University of Navarra, P.O. Box 177, 31080 Pamplona, Na-varra, Spain. E-mail: ebaquero@unav.es.3 Corresponding author: Grinnell College, Grinnell IA 50112 USA. E-mail: christak@grinnell.edu.Mailed on November 12, 200432 ENTOMOLOGICAL NEWSGenus Nothobrya Arl, 1961Diagnosis: The genus differs from other scaleless Orchesellinae by a combina-tion of falcate mucro, postantennal organ and curved hook-like labral papillae.Nothobrya schubarti Arl, 1961(Figs. 1-8)Body length: Excluding appendages: 1.5-2.0 mm (according to Arl), 0.95 mm and 1.16 mmrespectively for the slide mounted and the ethyl alcohol preserved specimens we studied.Color: Ground color of body pale yellow, with blue pigment on distal part of antennal segment I,final half of antennal segments II-III, distal two thirds of antennal segment IV, and bands on the ante-rior half of all tergites, coxae and trochanters (Fig. 1).Cuticle: Body seen under SEM with dense reticular pattern (Fig. 7). Scales absent.Head: Antennae six segmented with both the first and third segments very small (Figs. 2-3). Lengthin mm of segments 1-6: 0.02:0.05:0.01:0.09:0.12:0.17 respectively. Ommatidia 8+8, finely reticulatedwith A and B larger than the others. PAO is a vesicle (15 x 5 micrometers), narrowed in its inner side,situated in front and lateral to eyes A and B. In the specimens we saw the PAO is distorted as is the restof the body (Fig. 4). Labral formula: 4/554 (Fig. 5), with labral papillae hook-like (Fig. 6). Abdomen: Abdominal tergite IV 1.26, 1.8 times longer than abdominal tergite III.Chaetotaxy: Large macrosetae present on head, thoracic segments and abdominal segment I, withpointed tips (type two of Christiansen, 1958). Macrosetae shorter and very robust on abdominal seg-ment I-VI, with clear barbules. Mesosetae of different size, with barbs that give them a pubescentappearance. Bothriotricha 2-3-2 on abdominal segments II-IV respectively, as is characteristic ofalmost all Entomobryidae (Szeptycki, 1979).Tenaculum: With 4 plus 4 teeth, and two setae on the corpus.Furcula: Dentes ringed (Fig. 7) on basal three quarters, with the final portion narrowed and striat-ed transversally. Mucro falcate without basal spine.Leg: Trochanteral organ with three or four smooth setae. Foot complex: Tenent hair truncate. Pretarsus with a single short blunt seta. Claw elongate, withthe two teeth of the internal edges very basal, and without unpaired distal tooth in the two specimenswe observed. Unguiculus with four lamellae but the external two are very narrow and fused about twothirds of the way from the base to the apex of the unguiculus. The two inner lamellae fused near theapex (Fig. 8).Type-locality: Brazil, Parnaba (Piau), Fazenda Lama Prta, Ònumerosos ex. sbre a lama e noÒmud-crackÓ em volta da lagaÓ, XI.1960. R. Arl leg. Otto Schubart found three specimens fromPernambuco (Riacho Terra Nova, 5.IX.1937). Material deposited at Museu Nacional, UniversidadeFederal do Rio de Janeiro.Remarks: The PAO of N. schubarti was described by Arl as a vestigial vesi-cle. Barra (1999) described it as a vesicle with a cavity on the top, but probablythis observation resulted from the poor condition of the material he saw, long inethyl alcohol and collapsed. The SEM examination of a paratype revealed that thePAO is a vesicle larger than described by Arl; Figure 4 shows clearly the outlineof the vesicle and how it is partially collapsed inward. The chaetotaxy and smoothseta at the ventral side of the final whorl of leg III are similar to most genera of theEntomobryidae. The trochanteral organ is poorly developed, as mentioned by Arl,with three or four short and smooth setae. Arl mentioned an almost imperceptibleunpaired ungual tooth but we saw none under the SEM. The Òtype fiveÓ setae(Christiansen, 1958) are similar to those seen in Entomobrya (Fig. 7). The pecu-liar hooked labral papillae are similar to those seen in some species ofOrchesellides, Heteromurus and Dicranorchesella (Mari Mutt, 1985). The seg-mental ratios and the presence of 6 segmented antennae indicate that this genus isbest placed in the subfamily Orchesellinae.ACKNOWLEDGEMENTSWe are grateful to Dr. Mari Mutt (Department of Biology, University of Puerto Rico at Mayagez)for his useful information, and to Dra. de Mendoa (Museu Nacional, Departamento de Entomologia,Universidade Federal do Rio de Janeiro, Brazil) for the loan of the type material of Nothobrya withthe permission to prepare a specimen for SEM. Stephanie Peterson assisted in the preparation of themanuscript. LITERATURE CITEDArl, R. 1961. Novas espcies de colmbolas aquticas (Nota preliminar). Atas da Sociedade deBiologia do Rio de Janeiro 5:34-37.Vol. 115, No. 1, January & February 2004 33Figs. 1-4. Nothobrya schubarti. 1, Lateral habitus showing coloration, length of bar = 0.1mm. Figs. 2-4 length of bars = 10 micra. 2, First two antennal segments, showing the basalsubdivisions (SEM). The arrows point to the end of the two subsegments. 3, First anten-nal segment, PAO and first ommatidia (SEM). The arrow points to the end of the first sub-segment. 4, Detail of collapsed PAO (arrow) and two first ommatidia (SEM).Barra, J.-A. 1999. Un nouveau genre Capbrya avec deux nouvelles espces de la Province du Cap(Rp. Sud Africaine) (Collembola: Entomobryidae). Bulletin de lÕInstitut Royal Des SciencesNaturelles de Belgique 69:19-24.Bellinger, P. F., K. A. Christiansen, and F. Janssens. 1996-2004. Checklist of the Collembola:Families. http://www.collembola.org/taxa/collembo.htm [Last updated on 2004.03.29 by FransJanssens].Christiansen, K. A. 1958. The Nearctic members of the genus Entomobrya (Collembola). Bulletinof the Museum of Comparative Zoology, Harvard 118:440-545.Mari Mutt, J. A. 1985. Three new species of Orchesellides from North Korea (Collembola:Entomobryidae: Orchesellinae). International Journal of Entomology, 25(4):297-309.Szeptycki, A. 1979. Chaetotaxy of the Entomobryidae and its Phylogenetic Significance, Morpho-systematic studies on Collembola. IV. Polska Akademia Nauk Istytut Zoologiczny Krakow1979:45-47.34 ENTOMOLOGICAL NEWSFigs. 5-8. Nothobrya schubarti (SEM), length of bars = 5 micra. 5, Labrum (square: Fig.6). 6, Detail of hook-like labral papillae (arrow). 7, Partial view of the crenulate dens, withtwo setae to show their barbule morphology. 8, Unguiculus showing three of the fourlamellae and basal part of the unguis.

Redescription of Nothobrya schubarti Arlé, 1961 (Collembola, Entomobryomorpha)

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