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Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

AbstractStibadocerina Alexander, a monotypic genus, includes the only known Neotropical species of the family Cylindrotomidae, S. chilensis Alexander, 1929, from South Central Chile (ca. 36°50′S–42°17′S). In this paper, Stibadocerina chilensis is redescribed and illustrated in detail. A study of wing-vein homology in the subfamily Stibadocerinae is provided, to identify the components of the reduced radial sector in Stibadocerina and related taxa. The proposed hypotheses of wing-vein homology are tested, and the systematic position of Stibadocerina is assessed through a cladistic analysis of 13 characters of the male imago, scored for exemplar species of the four genera included in the Stibadocerinae. A single most parsimonious tree supports the monophyly of the Stibadocerinae and the following relationships among its included genera: Stibadocerodes [Stibadocera (Stibadocerella +Stibadocerina)]. The subfamily includes one example of a vicariant distribution with a sister-group relationship between South Central Chilean and East Asian taxa, and supports a biogeographical interpretation of an ancestral trans-Pacific biota.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

The Cylindrotomidae is the smallest of the four families of Tipulomorpha sensu stricto, with 71 extant species. Most of the genera and species belong to the subfamily Cylindrotominae, which is distributed mainly in the Nearctic and Palaearctic regions. The Stibadocerinae includes four genera: Stibadocera (12 species; Oriental–Australasian), Stibadocerella (four species; Oriental–Eastpalaearctic), Stibadocerodes (three species; Australasian) and Stibadocerina (one species; Neotropical) (Oosterbroek, 2008). Only the subfamily Cylindrotominae is known in the fossil record, mostly from Tertiary strata from North America and Europe (Evenhuis, 1994).

Stibadocerina chilensis is the sole member of the genus Stibadocerina Alexander, 1929, and the only species of Cylindrotomidae from the Neotropical region. The species was described mostly from specimens collected during an expedition to South Chile led by F. W. Edwards and R. C. Shannon, between November and December of 1926. The Diptera collected by the expedition were studied in a series of monographs published by the British Museum (Natural History), the Diptera of Patagonia and South Chile series, of which the first volume, dealing with the crane flies, was published in 1929 (Alexander, 1929).

My main purpose is to revise Stibadocerina chilensis, providing a more detailed morphological study of the taxon, and to assess its phylogenetic relationship to other genera within the Stibadocerinae. The wing venation in S. chilensis is quite distinct and reduced compared with the patterns commonly found in the Cylindrotomidae. Therefore, to understand the possible identities of the wing veins of the radial sector in S. chilensis and related taxa better, a study of the wing-vein homology in the Stibadocerinae is presented. The systematic position of Stibadocerina is assessed, and a preliminary phylogeny of the Stibadocerinae is provided, followed by a short discussion of biogeographical implications.

Materials and methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

Studied specimens of Stibadocerina, Stibadocera and Stibadocerella belong to the Natural History Museum, London, U.K. (BMNH). Other specimens used in the comparative study are from the collections of the Zoölogisch Museum, Amsterdam, The Netherlands (ZMAN), the United States National Museum, Smithsonian Institution, U.S.A. (USNM), and the Departamento de Biologia, FFCLRP-Universidade de São Paulo, Ribeirão Preto, Brazil (DBRP). Details on the examined specimens of Stibadocerina are provided under the redescription of the species. Details on the other specimens used for phylogenetic analysis are given in Appendix 1.

For most characters, the descriptive terminology follows McAlpine (1981), with terminology for male gonostylus structures following Ribeiro (2006). The adopted terminology for the wing veins accords with the results of the homology study below.

Male terminalia were cleared with warmed KOH and mounted in non-permanent slides with glycerol. After study and illustration, the dissected parts were transferred to microvials and pinned with their corresponding specimens. Illustrations were produced with drawing tubes attached to stereoscopic and compound microscopes. Measurements were taken with an ocular reticule.

To test the phylogenetic information of the primary homology hypotheses for the wing veins, and to elucidate the phylogenetic position of Stibadocerina, 13 characters from the male imago were scored for species representing the four genera of Stibadocerinae as the in-group, plus two genera of the subfamily Cylindrotominae and six exemplars of the families Limoniidae and Tipulidae as out-groups. Characters were scored from the direct observation of specimens for all taxa except Stibadocerodes zherikhini and Phalacrocera replicata, which were based on literature (Brodo, 1967; Krzeminski, 2001). All characters were considered as unordered. Character polarity was determined a posteriori with rooting using the out-group method. The characters are described in Table 1, and the data matrix is shown in Table 2. The data matrix was analysed in TNT (Goloboff et al., 2003) with tree bisection–reconnection (TBR) branch swapping, random stepwise addition and 1000 replications holding up to 10 trees. The matrix was analysed using both prior (equal) weights and implied weights (with k varying from 2 to 6).

Table 1.  Characters scored for phylogenetic analysis. Consistency index within square brackets.
1. Proportion between the length and width of first and second flagellomeres: less than 3× longer than wide (0); more than 3× longer than wide (1). [0,5].
2. Vein Sc: reaching the wing margin (0); atrophied and not reaching the wing margin (1). [1,0].
3. Vein R1: reaching the wing margin (0); atrophied at tip and not reaching the wing margin (1). [0,5].
4. Vein R1: ending on C at a more distal position (0); ending on C in a more proximal position (1). [1,0].
5. Vein r-r: transversal in position (0); oblique in position, but still distinguishable (1); aligned with R1 and distal section of R2 (2). [1.0].
6. Vein R2+3: shorter than one-half the length of R3 (0); longer than one-half the length of R3 (1); absent (2). [0,66].
7. Basal section of R2 (bR2): long (0); short (1). [1,0].
8. Basal section of R2 (bR2): sinuous (0); straight (1). [1,0].
9. Basal section of R2 (bR2): longitudinal in position (0); sub-perpendicular in position (1). [1,0].
10. Vein R4+5: present (0); absent (1). [1,0].
11. Vein M1+2: bifurcated (0); not bifurcated (1). [0,5].
12. Aedeagus: simple (0); trifid (1). [1,0].
13. Gonostylus: 2-branched with well-developed clasper and lobe (0); 2-branched, but with a reduced lobe (1); with a single branch (2). [0,66].
Table 2.  Data matrix for phylogenetic analysis. Inapplicable characters coded as ‘–’.
 12345678910111213
Edwardsomyia chiloensis1000000000000
Tinemyia margaritifera0000000000000
Ptilogyna sp.0001110000
Leptotarsus (Longurio) gymnocerus0000110000
Cylindrotoma distinctissima0101110012
Phalacrocera replicata0101110112
Stibadocerodes zherikhini101120001110
Stibadocera sp.1001101011111
Stibadocerella sp.101211111110
Stibadocerina chilensis101211111112

Results and discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

Homology of wing veins in Stibadocerinae

In crane fly systematics, the homology and nomenclature of the wing veins has been a contentious issue, with different systems currently in use by different authors. The situation is especially problematical regarding the identity of the veins of the radial sector, which shows much plasticity and high levels of homoplasy.

The proposal of homology relations for wing veins, and the understanding of the possible modifications leading from more generalized to highly modified patterns are biased, after all, by the proponent’s conceptions of what constitutes the plesiomorphic condition for the various wing-vein characters, and what would constitute plausible changes. When phylogentic studies are lacking, such ground-plan formulations can be quite subjective and intuitive. In the absence of information on the developmental paths and the underlying mechanisms behind changes in the venation, judgments on the plausibility of certain transformations are also very subjective and difficult to test more directly.

A recent study of the early phylogenetic patterns of crane flies (Ribeiro, 2008) allowed a better understanding of the possible ground-plan condition of the wing venation in the Tipulomorpha sensu stricto. Regarding the radial sector, the following conditions seem likely to be present:

  • 1
    The vein R1 reaches the wing margin.
  • 2
    The cross-vein r-r is present, perpendicular in position, and is closer to the mid-point of vein R2 than to either its origin or its apex.
  • 3
    Veins R2 and R3 both reach the wing margin and run more or less in parallel or only gradually diverging from each other.
  • 4
    The petiole of cell r2 (vein R2+3) is short, or more precisely, shorter than one-half the length of vein R3.
  • 5
    Veins R4 and R5 are fused in a single element R4+5 reaching the wing margin. There is some doubt whether this condition for R4+5 is the ground-plan condition of the entire Tipulomorpha sensu stricto, because at least one species in the family Pediciidae (Tricyphona protea, figured in Alexander & Byers, 1981, figure 38) seems to have retained a free vein R5. However, with the likely position of Pediciidae as the sister group of all other Tipulomorpha sensu stricto (Ribeiro, 2008), it seems quite safe to assume that a single element R4+5 is present in the ground-plan of the other Tipulomorpha except Pediciidae. The conditions described above are preserved in many Limoniidae genera, of which Edwardsomyia is a good example (Fig. 1).
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Figure 1–9. Proposed homology for the wing veins. 1, Edwardsomyia chiloensis (Limoniidae: Limnophilinae); 2, Stibadocerodes australensis (Cylindrotomidae: Stibadocerinae); 3, Stibadocerodes tasmanensis (Cylindrotomidae: Stibadocerinae); 4, Stibadocerodes zherikhini (Cylindrotomidae: Stibadocerinae); 5, Stibadocera sp. (Cylindrotomidae: Stibadocerinae); 6, Stibadocerella sp. (Cylindrotomidae: Stibadocerinae); 7, Stibadocerina chilensis (Cylindrotomidae: Stibadocerinae); 8, Phalacrocera replicata (Cylindrotomidae: Cylindrotominae); 9, Cylindrotoma distinctissima (Cylindrotomidae: Cylindrotominae).

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Instead of considering previous hypotheses of homology and the nomenclature applied to the Cylindrotominae (e.g. Brodo, 1967; Alexander & Byers, 1981), the comparisons made here start from the acceptance of the ground-plan conditions as described above.

Among all Stibadocerinae genera, Stibadocerodes (Figs 2–4) is the one in which the characters of the radial sector match most closely that of the ground-plan. Without assuming much transformation from the basic pattern, the most obvious difference is the lack of the element R4+5 in all species, and the loss of the petiole of cell r2 (vein R2+3) in S. tasmanensis (Fig. 3) and S. zherikhini (Fig. 4). Furthermore, the tip of R1 obviously is lacking in all species. In S. australensis (Fig. 1), a fragment of the tip of R1 remains, but with vein r-r positioned as in the original configuration. However, in S. tasmanensis and S. zherikhini, (Figs 3, 4) the cross-vein r-r seems ‘captured’ by the basal remnants of R1, producing a single element (R1+ r-r).

In Stibadocera (Fig. 5), the situation is more distant from the original conditions. Although still present, the tip of R1 is positioned in a much more proximal location, and the vein r-r assumes a more oblique position. The petiole of cell r2 (vein R2+3) is still present. The anterior displacement of R1 seems to have caused a distortion in the basal section of vein R2 (bR2), which is more inclined and shorter than in Stibadocerodes. Nonetheless, there seems to be little doubt, within the framework of the comparisons being made here, that the sinuous, sub-perpendicular element in the radial sector of Stibadocera is the basal section of vein R2 (bR2).

We now approach the more apomorphic conditions of the radial sector as found in Stibadocerella (Fig. 6) and Stibadocerina (Fig. 7). Understanding the identities of these veins in these genera would be very difficult if they were taken in isolation; however, the study of the identity of the veins in related genera furnishes evidence of what could have happened in these derived groups.

Starting from a condition similar to that of Stibadocera, a simple change, the loss of the tip of R1, could result in a dramatic change in the overall appearance of the radial sector. The vein r-r would, as in the case of Stibadocerodes tasmanensis and S. zherikhini, be ‘captured’ by the basal remnants of R1. In this case, as a result of the more inclined position of r-r, its ‘capture’ would result in a single element R1+ r-r almost continuous with, or aligned with, the apical section of vein R2. These transformational events, together with the elongation of the vein R2+3, are all that needs to be assumed to conclude that the first longitudinal vein of the radial sector in Stibadocerella and Stibadocerina forms a composite vein comprising an element (R1+ r-r) aligned or almost aligned with the distal section of R2. The sub-perpendicular or almost transversal element of the sector is the basal section of vein R2 (bR2). The second longitudinal vein is the primitive R3.

The wing venation of other Cylindrotominae, Phalacrocera replicata (Fig. 8) and Cylindrotoma distinctissima (Fig. 9) are shown for comparison.

Taxonomy

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

Genus Stibadocerina Alexander, 1929

Stibadocerina Alexander, 1929: 66. Type species: Stibadocerina chilensis Alexander, 1929.

DiagnosisStibadocerina differs from Stibadocerodes and Stibadocera mainly by having the vein r-r indistinguishable, aligned with both R1 and the distal section of R2. It differs from Stibadocerella by keeping the second anal vein (lost in Stibadocerella) and having a single, unbranched gonostylus.

Stibadocerina chilensis Alexander, 1929 (Figs 7, 10–16)

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Figure 10. Stibadocerina chilensis. Head (anterolateral view) and thorax (lateral view). Abbreviations: anatg, anatergite; anepm, anepimeron; anepst, anepisternum; anepst cleft, anepisternal cleft; aprn, antepronotum; comp eye, compound eye; cx, coxa; kepm, katepimeron; kepst, katepisternum; ktg, katatergite; lbl, labella; ltg, laterotergite; mr, meron; mtanepst, metanepisternum; mtepm, metaepimeron; mtg, mediotergite; mtkepst, metakatepisternum; ped, pedicel; plp, maxillary palpus; pprn, postpronotum; scp, scape; sct, scutum; sctl, scutellum.

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Figure 11. Stibadocerina chilensis. Wing venation.

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Figure 12. Stibadocerina chilensis. Detail of wing venation, showing the position of the tip of Sc vein in relation to other veins, not visible in Fig. 11.

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Figure 13. Stibadocerina chilensis. Male terminalia, dorsal view. Abbreviations: aed, aedeagus; goncx, gonocoxite; gonst, gonostyle; t9, ninth tergite.

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Figure 14. Stibadocerina chilensis. Male terminalia, dorsolateral view. Abbreviations: aed, aedeagus; goncx, gonocoxite; gonst, gonostylus; s8, eighth sternite; t8, eighth tergite; t9, ninth tergite.

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Figure 15. Stibadocerina chilensis. Aedeagus and associated structures. Abbreviations: aed, aedeagus; aed apod, aedeagus apodeme; interb, interbase; lp, lateral process of aedeagal sheath; pm, paramere.

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Figure 16. Stibadocerina chilensis. Female ovipositor. Abbreviations: cerc, cercus; hyp vlv, hypogynial valve; s8, eighth sternite; t10, tenth tergite.

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Stibadocerina chilensis Alexander, 1929: 66 (original description); Plate II, figure 37 (wing venation). Alexander & Alexander, 1970: 4.44 (catalogue citation); Oosterbroek, 2008 (catalogue citation).

Colour (male and female) Head dark brown; antenna, rostrum and palpus brownish; pronotum light brown; legs mostly light brown–yellowish, with last 4–3 tarsal segments white. Scutum brown; lateral thoracic sclerites mostly brown, light brown–yellowish near attachment of wing and halter; wing with a brownish tinge; mesothoracic and metathoracic coxae and base of first abdominal segment light brown–yellowish; abdomen from second segment to tip uniformly brown.

Dimensions (male; maximum lengths and widths in mm) Head length, 0.53; head width, 0.53–0.60; wing length, 5.62–5.93; wing width, 1.31; gonocoxite length, 0.22; gonocoxite width, 0.15; gonostylus length, 0.16.

Morphology Head and appendages (Fig. 10): antenna longer in male than in female; flagellum 13-segmented, covered with verticils shorter than individual flagellomeres; flagellomeres cylindrical, decreasing in length towards tip of antenna; first flagellomere ca. 10× longer than wide in male, ca. 5× longer than wide in female; pedicel ca. 1.7× longer than scape; palpus 4-segmented; palpomeres more or less cylindrical; last palpomere almost as long as preceding segments together; rostrum (including labella) ca. 0.30× the total length of head; compound eyes widely separated dorsally and ventrally. Thorax and appendages: thorax almost as long as high; pleural sclerites as figured (Fig. 10); tibial spurs absent; tarsal claw simple. Wing (Figs 7, 11, 12): vein h situated at mid-length between the origin and the fork of M + Cu; Sc running very close to R, ending on C just distally of the origin of Rs; sc-r faint or absent, when present placed at tip of Sc; Rs almost straight, except for slight curvature at origin; two elements of Rs (R2 and R3) reaching wing margin; vein R2+3 almost as long as R3; basal section of R2 (bR2) straight, sub-perpendicular; vein M with tree branches, M1+2, M3 and M4; m-cu placed slightly proximal to mid-point of discal cell; Cu strongly curved; A1 running very close to Cu at its basal section, gently curved and reaching the wing margin at the level of the origin of R2+3; A2 slightly sinuous, reaching wing margin well before the origin of Rs. Male terminalia (Figs 13–15): ninth tergum and sternum separated, not forming a contiguous ring; ninth tergum produced into a single small median lobe; gonocoxite globular, almost as long as high, with a large ventro-medial hairy projection; gonostylus simple, unbranched, gradually narrowed towards tip, slightly curved at apex; aedeagus trifid, with medial branch slightly longer than lateral branches; lateral process of aedeagal sheath well developed and stout, branching off from the sheath obliquely, not in parallel with the aedeagus; interbase slender, almost straight from base to apex, bearing a relatively stout and well-developed lateral extension articulating with gonocoxite apodeme, and a similar posterior extension articulating with paramere; interbases connected to each other medially. Female terminalia (Fig. 16): tenth tergite approximately as long as cercus, more or less triangular in lateral view; cercus like a stout curved blade; hypogynial valve reaching mid-length of cercus, with its tip aligned with apex of tenth tergite.

DistributionStibadocerina chilensis is known to occur only in South Central Chile, with its northernmost limit at Concepcion (ca. 36°50′S, 73°00′W) and its southernmost limit at Mechuque Island (ca. 42°18′S 73°15′W).

Examined material (label information in italics; information of different labels separated by a vertical line; geographical coordinates within brackets): HOLOTYPE. ♂. S. Chile: Llanquihue prov. F.&M.Edwards. B.M. 1927-63. | Peulla. 12-13.xii.1926. | BMNH(E)#246146. (41°03′S 71°01′W); ALLOTYPE. ♀. S. Chile: Llanquihue prov., F.&M. Edwards., B.M.1927-63. | Peulla., 12-13.xii.1926. (41°03′S 71°01′W); PARATYPES. 3 ♂. S. Chile: Llanquihue prov. F.&M.Edwards. B.M. 1927-63. | Peulla. 12-13.xii.1926. (41°03′S 71°01′W); PARATYPE. ♂. S. Chile: Llanquihue prov. F.&M.Edwards. B.M. 1927-63. | Casa Pangue, 4-10.xii.1926. (41°02′S 71°51′W) PARATYPE. ♀. S. Chile: Chiloe I., F. & M. Edwards., B.M.1927-63 | Mechuque I., 23.xii.1926(42°18′S 73°15′W).

Phylogenetic position of Stibadocerina

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

The parsimony analysis of the data matrix in TNT (Goloboff et al., 2003) using both prior (equal) weights and implied weights (with any value of k) results in the same single most parsimonious tree (21 steps; CI = 0.761; RI = 0.833), of which the relationships for the in-group taxa are shown in Fig. 17.

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Figure 17. Cladogram depicting relationships among exemplar species of Cylindrotominae and Stibadocerinae genera. Unique and homoplastic characters represented by closed and open circles, respectively.

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The monophyly of the Cylindrotomidae (Clade A) is corroborated by the trifid aedeagus, a synapomorphy unique to this family within the Tipulomorpha sensu stricto. The monophyly of the Cylindrotominae (Clade B) is supported also by at least two synapomorphies: the loss of one of the gonostylar branches (character 2, state 1) and the atrophy of the tip of vein Sc (character 13, state 2).

The monophyly of the Stibadocerinae (clade C) is corroborated by the long flagellomeres (character 1, state 1) and the loss of vein R4+5, a character state unknown to have occurred in any other lineage within the Tipulomorpha.

Stibadocerodes constitutes the sister-group to all other Stibadocerinae. The clade Stibadocera + (Stibadocerela +Stibadocerina) (Clade D) is grouped on the basis of the reduction and inclination of the basal section of vein R2 (character 7, state 1, and character 9, state 1).

The monotypic Stibadocerina is placed as the sister-group of Stibadocerella (Clade E). The synapomorphies uniting these taxa are the alignment of the vein r-r with R1 and the distal section of R2 (character 5, state 2), and the straight basal section of vein R2 (bR2) (character 8, state 1). This picture is consistent with the opinion of Alexander (1929) who, in describing Stibadocerina, pointed to Stibadocerella as its most closely related taxon.

The sister-group relationship between Stibadocerina and Stibadocerella seems well supported. The monophyly of Stibadocerella also is well supported by the loss of the second anal vein. However, to test the monophyly of Stibadocerodes and Stibadocera a taxonomic revision and phylogenetic study including more taxa is necessary.

Trans-Pacific disjunction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

The subfamily Cylindrotominae is widespread in the Holarctic Region, but the Stibadocerinae has a much more restricted distribution: Stibadocerina is endemic to South Central Chile between ca. 36°50′S and 42°18′S; Stibadocerella is known from the eastern part of the Oriental region; Stibadocera has an East Oriental–Australasian range; and Stibadocerodes is restricted to New South Wales and Tasmania (Fig. 18).

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Figure 18. Distributions of the genera Stibadocerodes (1), Stibadocera (2), Stibadocerella (3) and Stibadocerina (4), with cladogram superimposed on it. The map is schematic and not to scale.

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Recent studies have reinforced the biogeographical affinities between components of the faunas and floras on both sides of the Pacific Ocean (for a recent review and examples, see Grehan, 2007). Among these groups there are examples of taxa with limited dispersal capabilities, indicating vicariance as a major cause for multiple trans-Pacific disjunctions (McCarthy et al., 2007).

A list of putative trans-Pacific sister areas is given by McCarthy (2003), based on evidence from several studies, including examples from the Diptera (revised in Cranston, 2005). According to McCarthy (2003), the area labelled as South Central Chile (35°S–42°S) is probably the sister-area of Tasmania (40°S–43°S), whereas Northern Australia and Indochina (23°N–23°S) (i.e. the area including the distributional ranges of both Stibadocera and Stibadocerella) is the sister group of northern South America and southern North America (23°N–23°S).

As pointed out by Cranston (2005), there are few examples of trans-Pacific disjunctions within the Diptera, and this study provides one particular case in the Tipulomorpha. The trans-Pacific clade Stibadocerella +Stibadocerina adds further evidence in favour of an ancestral biota centred around a more spatially restricted Pacific basin, as opposed to the conventional interpretation with a Panthalassan Ocean occupying the non-continental half of the globe (and thus implying trans-Pacific disjunctions as derived from long-distance dispersals or relicts of prior vicariance events). However, the closest relationship as indicated by this study, namely that between the northern part of the Australasian and the eastern part of the Oriental regions (ca. 23°N–8°S) to South Central Chile (36°S–46°S), does not fit exactly in the framework of trans-Pacific sister areas given by McCarthy (2003). This may be evidence of a more complex picture, and indicate that additional evidence is necessary for a better understanding of the complex relationships of the areas around the Pacific basin.

Acknowledgements

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

I am very indebted to Dr Erica McAlister (Natural History Museum, London, U.K.), Dr Pjotr Oosterbroek (Zoölogisch Museum, Amsterdam, the Netherlands) and Dr Wayne Mathis (Smithsonian Institution, Washington DC, U.S.A.) for the loan of the specimens used for this study, and to Dr Jaroslav Starý for the exchange of literature. Special thanks to Dr John R. Grehan for advice concerning other cases of trans-Pacific disjunctions. At the time this research was conducted, I was supported financially by a post-doctorate fellowship from FAPESP.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix
  • Alexander, C.P. (1929) Diptera of Patagonia and South Chile. Part I. Crane-flies (Tipulidae, Trichoceridae, Tanyderidae). Diptera of Patagonia and South Chile, 1, 1240.
  • Alexander, C.P. & Alexander, M.M. (1970) Family Tipulidae. A Catalogue of the Diptera of the Americas South of the United States (ed. By N. Papavero), pp.4.14.259. Museu de Zoologia, Universidade de São Paulo, São Paulo, Brazil.
  • Alexander, C.P. & Byers, G.W. (1981) Tipulidae. Manual of Nearctic Diptera (Research Branch, Agriculture Canada, Monograph 27) (ed. by J. F. McAlpine, B. V. Peterson, G. E. Shewell, H. J. Teskey, J. R. Vocheroth and D. M. Wood), Vol. 1, pp. 153190. Research Branch, Agriculture Canada, Ottawa, Canada.
  • Brodo, F. (1967) A review of the subfamily Cylindrotominae in North America (Diptera: Tipulidae). The University of Kansas Science Bulletin, 47, 71115.
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Appendix

  1. Top of page
  2. Abstract
  3. Introduction
  4. Materials and methods
  5. Results and discussion
  6. Taxonomy
  7. Phylogenetic position of Stibadocerina
  8. Trans-Pacific disjunction
  9. Acknowledgements
  10. References
  11. Appendix

Appendix 1.

Information on the specimens used for comparative study. Each entry is a different specimen. The specimens of Stidabocerina chilensis are listed elsewhere in the text.

Limoniidae
  • 1
    Edwardsomyia chiloensis Alexander, 1929. Paratype, ♂, CHILE: Ancud, 18.xii.1926 (Shannon) (USNM).
  • 2
    Edwardsomyia chiloensis Alexander, 1929. 1♂, CHILE: Chiloe I., Aucar, 6-15.i. 1952 (Peña) (USNM).
Tipulidae
  • 3
    Leptotarsus (Longurio) gymnocerus (Alexander, 1938). Paratype, ♂, BRAZIL: Marambaia, 1100 m, 2.xii.1935 (Zikan) (USNM).
  • 4
    Leptotarsus (Longurio) gymnocerus (Alexander, 1938). Paratype, ♂, BRAZIL: Marambaia, 1100 m, 2.xii.1935 (Zikan) (USNM).
  • 5
    Ptilogyna sp. 1♂, BRAZIL: São Paulo, Salesópolis, E. B. Boracéia, Ponte Rio Claro, 14.xi.2003 (G. C. Ribeiro) (DBRP).
  • 6
    Ptilogyna sp. 1♂, BRAZIL: São Paulo, Salesópolis, E. B. Boracéia, Ponte Rio Claro, 14-16.xii.2003 (G. C. Ribeiro) (DBRP).
Cylindrotomidae (Cylindrotominae)
  • 7
    Cylindrotoma distinctissima (Meigen, 1818). 1♂, FRANCE: 23km N Sospel, pine forest, 1500 m, 14.vi.1997 (P. Oosterbroek and C. Hatveld) (ZMAN).
  • 8
    Cylindrotoma distinctissima (Meigen, 1818). 1♂, FRANCE: 23km N Sospel, pine forest, 1500 m, 14.vi.1997 (P. Oosterbroek and C. Hatveld) (ZMAN).
Cylindrotomidae (Stibadocerinae)
  • 9
    Stibadocera sp. 1♂, MALAYSIA: Sarawak, Mt. Dulit, R. Koyan, Primary Forest, 2500 ft, 21.xi.1932 (B. M. Hobby and A. W. Moore) (BMNH).
  • 10
    Stibadocera sp. 1♂, MALAYSIA: Sarawak, R. Kapah trib., of R. Tinjar., 25.x.1932 (B. M. Hobby and A. W. Moore) (BMNH).
  • 11
    Stibadocera sp. 1♂, MALAYSIA: Penang, Penang Hills, Ayer Itam 1000, 18.xii.1963 (H. T. Pagden) (BMNH).
  • 12
    Stibadocerella sp. 1♂, MALAYSIA: Sarawak, Mt. Dulit, Moss forest, 4000 ft, 25.x.1932 (B. M. Hobby & A. W. Moore) (BMNH).
  • 13
    Stibadocerella sp. 1♂, JAVA: Tjibooas, 4000 ft. i. 1936. (L. E. Cheesman) (BMNH).