The larvae and pupae of Tabanus lenticulatus Oldroyd and T. papuensis Oldroyd are described, illustrated, and compared with the other described larvae of Australasian species of Tabanus Linnaeus

Goodwin, James T.

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INSECTA MUNDI, Vol. 16, No. 1-3, March-September, 2002  121 Larvae and pupae of some New Guinean Tabanidae (Diptera). II. Species of the genus Tabanus Linnaeus James T. Goodwin Jarvis Christian College P.O. Box 1470 Hawkins, TX 75765-9989 Abstract: The larvae and pupae of Tabanus lenticulatus Oldroyd and T.  papuensis Oldroyd are described, illustrated, and compared with the other described larvae of Australasian species of Tabanus Linnaeus. Introduction In part I (Goodwin 2001), previous information on the immature stages of the Tabanidae of the Australasian and Oceanian Regions, and both ma-terials and methods and larval and pupal morphol-ogy  were  discussed.  In addition,  the larvae and pupae ofthe two species of Chrysops Meigen known from New Guinea were described and illustrated. The present report presents the descriptions of the larvae and pupae of two species of Tabanus, and compares the larval stages with those of the other four Australasian species for which larval descrip-tions have been provided (Taylor 1917; Hill 1921). These are the first  descriptions known for  New Guinea Tabanus and bring the total to four New Guinea species of Tabanidae for which the imma-ture stages are known. Tabanus lenticulatus Oldroyd Mature larva (Figure 1): Length 25-30 mm; entire larva dark brownish black dorsally and laterally except for small whitish dorsolateral spots on most segments and the pale beige pseudopodia; ventral surface whitish. Densely pubescent except for the middorsal,  sublateral,  and  posterior  surfaces  of prothorax, midventral surface of mesothorax, met-athorax, and abdominal segments 1-7 posterior to pseudopodia, midventral area of anal segment an-terior to anal  ridge, and a small dorsolateral spot on each side of mesothorax, metathorax, and abdomi-nal segments 1-6 which are non-pubescent; pubes-cence dark brownish black except on pseudopodia where it is pale beige. Head capsule 3.62 mm long, greatest width 0.98 mm. Anal segment 2.88 mm long, ca. 1.5 times its greatest width. Respiratory siphon 0.58 mm long, ca. 1.5 times its basal diam-eter; stigmatal spine absent. Striations absent from non-pubescent areas, presumed absent elsewhere. Pupa (Figures 2A-2C): Length 15-18 mm; yellow-ish-brown without obvious darkened areas except for darker brown ofthoracic spiracular prominenc-es. Antennal ridges evident, but not sharply divid-ed into median and lateral parts, separated at the midline by a notch ca. 0.14-0.17 mm deep. Callus tubercles unisetose, more or less oval basally, not noticeably skewed at apex; elevated 0.15 mm above general surface. Frontal tubercles small, apically ridged, elevated 0.03-0.06 mm above general sur-face.  Antennal sheaths 0.61  mm long,  0.48  mm wide,  slightly exceeding epicranial suture in fe-male. Thoracic spiracles ca. 0.63 mm long; spiracu-lar prominence exceeding dorsal thoracic margin 0.29 mm. Abdominal fringes biseriate, completely encircling  segments  II-VII,  progressively  longer from anterior to posterior; dorsal fringe of 24-36 spines on tergite VII. Dorsal, lateral, and ventral or ventrolateral pre-anal combs of 3-5,5-7, and 15-17 or 5-6 spines, respectively, the ventrolaterals and laterals not widely separated in females.  Dorsal, lateral, and ventral tubercles of aster 0.36,  0.65, and 0.36 mm long, respectively; all rather slender and tapered to  pointed  apices;  dorsals  directed dorsoposteriorly, laterals directed lateroposterior-ly with a  sharp upward curve, ventrals directed ventroposteriorly. Collections and Comments: A total of 20 larvae was collected of which 6 were preserved. Six adults were reared including both males and  females. The pupal period averaged 10 days in duration with a range of 9-11 days. All larvae were collected at the crocodile rearing facility 6 km north of Lae along the Markham Highway. The larvae, all apparently full-grown, were found in moderately organic mud associated with the roots of tall grass growing in shallow rain-filled depressions.  These irregularly shaped depressions, some made by tires of heavy trucks, were only about 20 cm deep at their deepest 122  Volume 16, No. 1-3, March-September, 2002, INSECTA MUNDI Figure 1. Lateral diagram oflarva of Tabanus lenticulatus. point and not more than 2 m across at their widest point. All larvae were collected in January and February, 1997.  The depressions were completely dry by the beginning of March following a period of 30+ days without rain and remained so for several months. The extent of pubescence and its pattern and color give larvae of T.  lenticulatus an appearance unlike any other known larvae of the genus. Pre-served specimens are superficially similar to larvae of the NeotropicaliNearctic genus, Chlorotabanus, but the latter are usually greenish in life. The color and pattern of pubescence makes larvae of this species distinctive among the known larvae of the Australasian Region,  but it is not unlikely that similar color and pubescent pattern may be found in the larvae of related species such as T.  selene Schuurmans Stekhoven and T. sepikensis Oldroyd. a Tabanus papuensis Oldroyd Mature larva (Figure 3):  Length 28-36 mm, yel-lowish-white with contrasting dark brownish pu-bescent markings. Head capsule 4. 71mm long, great-est width 1.06 mm. Anal segment 4.78 mm long, ca. 1.67 times its greatest width. Respiratory siphon 1. 72  mm long,  ca.  2.5  times its basal diameter; stigmatal spine absent. Striations absent. Anterior pubescence encircles thoracic and first four abdom-inal segments, being absent dorso- and ventrolater-ally from abdominal segment V and from entire lateral area of segment VI,  and present only as small dorso- and ventrolateral spots on segment VII, totally absent from anal segment; prothoracic anterior annulus with a broad caudally projected fan-shaped pubescent extension laterally on each side crossing more than 80% of the length of the Figure 2. Photographs of portions of the pupa  of Tabanus lenticulatus: 2a, ventral  view offrontal plate; 2b, anterior view offrontal plate; 2c, aster. All photographs by Jeffrey Lotz, FDACS-DPI, Gainesville, FL. INSECTA MUNDI, Vol. 16, No. 1-3, March-September, 2002  123 Figure 3. Lateral diagram of larva of Tabanus papuensis. segment, anterior annuli ofthe meso- and metatho-rax with broad lateral posterior projections that attain posterior margins of  the segments. Pseudopo-dial pubescence forming complete annuli on first four pseudopodial segments, being absent between lateral and ventrolateral pseudopodia on remain-ing  segments;  united  with  anterior  pubescence dorso- and ventrolaterally on first four segments. Posterior pubescence encircles all abdominal seg-ments, faintly and narrowly on first six; posterior annulus of abdominal segment VII expanded later-ally to project anteriorly to near the middle of the segment;  broad,  dark posterior  annulus  of anal segment with a broad lateral anterior projection on each side that curves sharply downward to unite with the pubescence covering the anal ridge and lobes; each anterior projection bearing a short an-terior projection near the midline. a Pupa (Figure 4a-4c): Length 24-28 mm; yellowish-brown without obvious darkened areas except for slightly darker brown of thoracic spiracular prom-inences. Antennal ridges evident only as rather smoothly rounded, swollen area separated at the midline by a  notch ca.  0.06-0.09 mm above deep. Callus tubercles unisetose, more or less oval basal-ly, slightly skewed laterally at apex; elevated 0.22 mm above general surface. Frontal tubercles small, elevated at most 0.02-0.03 mm. Antennal sheaths 0.67 mm long,  0.53  mm wide,  slightly exceeding epicranial suture in female. Thoracic spiracles ca. 1.38  mm  long;  spiracular prominence  exceeding dorsal thoracic  margin by 0.72  mm.  Abdominal fringes biseriate, complete dorsally and laterally on segments II-VII, progressively longer from anteri-or to posterior; ventrally limited to a single relative-ly long pair located sublaterally on sternites II-IV, to a similar pair plus numerous short spines lateral of the two long spines on sternite V,  completely Figure 4. Photographs of portions ofthe pupa of Tabanus papuensis: 2a, ventral view offrontal plate; 2b, anterior view offrontal plate; 2c, aster. All photographs by Jeffrey Lotz, FDACS-DPI, Gainesville, FL. 124  Volume 16, No. 1-3, March-September, 2002, INSECTA MUNDI traversing sternites VI  &  VII  but small on VI; dorsal fringe of 40-54 spines on tergite VII. Dorsal, lateral, and ventral or ventrolateral pre-anal combs of  6-7,  0,  and 16-18 or 6-7 spines, respectively. Dorsal, lateral, and ventral tubercles of aster 0.21, 0.42, and 0.29 mm long, respectively; all tapered to pointed apices; dorsals directed dorsoposteriorly, laterals  directed  lateroposteriorly with  a  slight upward curve, ventrals directed ventroposteriorly. Collections and Comments: Collecting at two locations yielded a total of 16 larvae from which 7 adults were reared including both males and fe-males. One location was the crocodile rearing facil-ity where the previous species was collected. How-ever,  the  actual  collecting  site  for  larvae  of T. papuensis was a  narrow, shallow drainage ditch that drained the crocodile rearing ponds and feed-ing areas. This is the same site that yielded larvae of Chrysops albicinctus and C.  australis described previously (Goodwin 2001). Larvae of T. papuensis were  in highly  organic,  silty  mud  and  usually associated with roots of tall grasses growing at the edge  of the  ditch.  The  second location was  the Markham Ranch about 55 km outside Lae along the Markham Highway. Larvae were collected at two sites,  both sluggish streams, and from locations similar to that noted for larvae found at the croco-dile rearing facility. The larvae of T.  papuensis have a  pubescent pattern and appearance more typical of the genus based on known larvae from  other parts of the world. They are readily distinguished from those of the  heavily  pubescent  T.  lenticulatus  described above and can be separated from the four other Australasian species of Tabanus for which larvae are known by the pubescent pattern of the thoracic segments.  In  T.  papuensis,  this  pubescence  in-cludes an anterior annulus and a broad fan-shaped lateral  posterior  projection  on  each  side  of the prothorax and an anterior annulus with a  broad midlateral band that attains the posterior margin on both the meso- and metathorax, whereas the other known Australasian Tabanus larvae (T.  dor-sobimaculatus Macquart, T. pallipennis Macquart, T.  particaecus Hardy, and T.  townsvilli Ricardo) have the lateral posterior  pubescent extensions from the anterior annuli of the thoracic segments comprised of  two (prothorax) or four (meso- and metathorax) slender projections that cross no more than 70% of the segments, or no posterior projec-tions at all. Literature cited Goodwin, J. T.  2001. Larvae and pupae of some New Guinea Tabanidae (Diptera). I. Species of Chrysops Meigen. Insecta Mundi 15: 1-5. Fuller,  1937.  Notes  on the biology  of  Tabanus froggatti, T. gentilis, and T. neobasalis (Diptera, Tabanidae). Proceedings of the Linnaean Soci-ety of New South Wales 62: 217-229. Johnston, T. H. and M. J. Bancroft. 1920. Notes on the life history of certain Queensland taban-id flies.  Proceedings of the Royal Society of Queensland 32: 125-131. 

Larvae and pupae of some New Guinean Tabanidae (Diptera) : 2. Species of the genus Tabanus Linnaeus

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