Anastrepha sp. near protuberans

Rodriguez, Erick J., Steck, Gary J., Moore, Matthew R., Norrbom, Allen L., Diaz, Jessica, Somma, Louis A., Ruiz-Arce, Raul, Sutton, Bruce D., Nolazco, Norma, Muller, Alies & Branham, Marc A., 2022, Exceptional larval morphology of nine species of the Anastrepha mucronota species group (Diptera, Tephritidae), ZooKeys 1127, pp. 155-215 : 155

Anastrepha sp. near protuberans

Figs 95-99 , 100-105 , 106-108

Material examined.

Ecuador • 5 larvae; Orellana, Estacion Cientifica Yasuni , trail 6, near tower; 0.6805°S, 76.3851°W; 247 m a.s.l.; 6 Jan. 2018; M. R. Steck, G. J. Steck, E. J. Rodriguez and A. Padilla leg.; reared from fruit of Sterculia frondosa Rich. ( Malvaceae ); FSCA (AP20180321.01, AP20180321.02, AP20200622.09-AP20200622.11) .

Diagnosis.

The larva of Anastrepha sp. near Anastrepha protuberans differs from those of other species of Anastrepha except A. crebra , A. haplacantha , A. korytkowskii , A. nolazcoae , Anastrepha sp. Peru-82, and Anastrepha sp. Sur-16 by the fringed posterior margins of their oral ridges and accessory plates. Anastrepha sp. near Anastrepha protuberans can be distinguished from the latter six species in having a greater apical width of the prothoracic spiracle and slit length of the posterior spiracle. The number of oral ridges, number of tubules on the prothoracic spiracle, and dorsal spinule pattern on the thoracic segments further distinguish Anastrepha sp. near Anastrepha protuberans from species in the Anastrepha mucronota group (see Tables 2 , 3 ).

Description.

Habitus. Third instar elongate, cylindrical, tapered anteriorly and caudal end truncate; color creamy; amphipneustic. Length 14.43-17.15 mm and width 2.52-2.68 mm at the sixth abdominal segment.

Pseudocephalon (Figs 95-98 ). Antenna and maxillary palp on moderately developed lobe. Antenna with cylindrical base and apical knob. Maxillary palp bearing three papilla sensilla, two knob sensilla; dorsolateral group of sensilla bearing two well-developed papilla sensilla, aligned at strongly oblique angle to palp and surrounded by a collar. Facial mask globular in lateral view. Preoral organ bearing three unbranched peg sensilla, located apically on simple elongate preoral lobe lateral to mouthhook. Oral ridges in 18-23 rows, posterior margins densely and evenly fringed; accessory plates present covering a much smaller area than oral ridges, with fringed posterior margins longer than oral ridges, apparently in one series. Labium triangular, anterior surface knobby, ventrally with two visible sensilla and tubercles.

Cephaloskeleton (Figs 99 - 101 ). Total length from tip of mouthhook to end of ventral cornu 1.48-1.51 mm. Mouthhook well sclerotized, black apically and basally; length a 0.34-0.35 mm; length b 0.24-0.25 mm; height c 0.26-0.28 mm; ratio a:b 1.41-1.46; ratio a:c 1.25-1.30. Tooth long, sharp, strongly curved, concave ventrally with smooth surface. Intermediate sclerite 0.24-0.26 mm long, 0.15 mm wide at ventral bridge. Epipharyngeal sclerite visible only in dorsal view, with medial lobe directed anteriorly. Labial sclerite robust, sclerotized, and triangular in dorsal view. Parastomal bar extending three-fourths length of intermediate sclerite. Dorsal arch 0.33-0.35 mm high. Dorsal cornu with well-defined sclerotized area adjacent to notch, 0.64-0.74 mm long. Dorsal bridge prominently projecting anteriorly from dorsal cornu and sclerotized. Anterior sclerite irregularly shaped and sclerotized. Cornu notch (N) 0.37-0.52 mm long and cornu notch index (N/DC) 0.57-0.69. Ventral cornu with well-defined sclerotized area from notch to pharyngeal bar and grooves. Pharyngeal filter with weakly sclerotized anterior bar and eight or nine ridges forming a series of grooves along length of ventral cornu. Ventral cornu 0.93-1.01 mm long from pharyngeal bar to posterior end of grooves. Ventral cornu 1.26-1.57 × as long as sclerotized area of dorsal cornu.

Thoracic and abdominal segments. Thoracic segments with dorsal spinules conical, symmetrical to slightly curved posteriorly; dorsal spinule pattern as follows: T1 with three rows; T2 with four or five rows; T3 with four rows; ventral spinule pattern as follows: T1 with 13 or 14 rows; T2 with 4-6 rows; T3 with 3-5 rows. Abdominal segments with dorsal spinules as follows: A1 with two rows; A2-A8 lacking spinules; ventral creeping welts present on all abdominal segments; ventral spinule pattern as follows: A1 with 5-8 rows; A2 with 6-9 rows; A3 with eight or nine rows; A4 with 9-12 rows; A5 with 8-12 rows; A6 with 9-11 rows; A7 with seven or eight rows; A8 with 6-9 rows. Additional three irregular rows of spinules anterior and posterior to anal lobes, lateral rows apparently absent, spinules large, conical, pointing away from anal lobes.

Prothoracic spiracle (Figs 102 , 103 ). Bilobed, bearing 22-30 tubules, distally rounded and arranged in a single, sinuous row except medially when spacing is irregular. Spiracle distal width 0.41-0.44 mm; basal width 0.18-0.20 mm at junction with trachea.

Caudal segment (Figs 104 , 105 ). Dorsal (D1 and D2) tubercles and sensilla weakly developed; D1 distinctly anterior to D2. Intermediate tubercles I1 and I2 more strongly developed, but associated sensilla moderately developed; I1 distinctly anterior to I2. L1, V1, and V2 tubercles and associated sensilla weakly developed. Anal lobe entire and protuberant.

Posterior spiracle (Figs 104 , 106-108 ). Located above horizontal midline. Posterior spiracle openings with thick rimae and numerous trabeculae; 122-145 µm long; 40-48 µm wide; ratio length/width 2.8-3.4. Ecdysial scar apparent. Felt chamber oval, 271-305 µm in diameter at junction with trachea. Spiracular process SP-I comprising 5-11 trunks and 9-20 tips; ratio tips/trunks 1.4- 2.5; basal width 8-11 µm; ratio basal width/length of spiracular opening 0.06-0.08. SP-II comprising 4-9 trunks and 11-19 tips. SP-III comprising 4-8 trunks and 7-16 tips. SP-IV comprising 7-10 trunks and 14-21 tips; ratio tips/trunks 1.55-2.6; basal width 9-12 µm; ratio basal width/length of spiracular opening 0.07-0.09.

Distribution.

Anastrepha sp. near Anastrepha protuberans is known only from Ecuador and Peru.

Biology.

We collected larvae of this species from fruit of Sterculia frondosa , the first host plant record. The larvae feed only on the seeds of the fruit.

Molecular identification.

COI barcodes were generated from five larvae from Ecuador and two adults from Peru and submitted to GenBank (MT672163-MT672165, MT763909-MT763911, MT763914). The identity of the described larvae is only based on these data. K2P distances between Anastrepha sp. nr. protuberans larvae and the adult sequences ranged from 0.0-1.2%. BLAST searches yielded no close matches to sequences from other Anastrepha species. The five larval barcodes returned consensus identifications of Anastrepha sp. nr. protuberans with either three or two votes ( Moore et al. in press).

Figures

Figures 95 - 99. Scanning electron photomicrographs of third instar of Anastrepha sp. nr. protuberans 95 pseudocephalon 96 oral ridges 97 antenna and maxillary palp 98 preoral organ 99 ventral surface of mouthhook. Scale bars: 10 μm (97, 98); 20 μm (99); 50 μm (96); 50 μm (95).

Figures 100 - 105. Optical photomicrographs and scanning electron photomicrographs of third instar of Anastrepha sp. nr. protuberans 100 cephaloskeleton, lateral view 101 cephaloskeleton, dorsal view 102 prothoracic spiracle, lateral view 103 prothoracic spiracle, dorsolateral view 104 caudal segment 105 anal lobe. Scale bars: 100 μm (102, 103, 105); 200 μm (100); 500 μm (101, 104).

Figures 106 - 108. Scanning electron photomicrograph and optical photomicrographs of posterior spiracles of third instar of Anastrepha sp. nr. protuberans. Scale bars: 100 μm.