Merothrips meridionalis, Cavalleri & Lindner & O’Donnell, 2019

Cavalleri, Adriano, Lindner, Mariana Flores & O’Donnell, Cheryle A., 2019, Merothrips meridionalis sp. n. (Thysanoptera: Merothripidae), a new fungivorous species from subtropical South America, Zootaxa 4668 (2), pp. 277-282 : 279

Merothrips meridionalis sp. n. ( Figs 2–9 )

Female aptera. Body and legs brown with abdomen slightly lighter and head darkest ( Fig. 2 ); antenna uniformly brown ( Fig. 4 ). Antenna 8-segmented, sensoria on III & IV reduced to a very small circular lens; V–VII slightly narrowed to apex; antennal setae slender and shorter than the length of segment VII; surface microtrichia absent. Head with well-developed eyes, with 15 or more facets ( Fig. 3 ); ocelli absent; ocellar setae pairs I and II minute, III long and arising near compound eyes; outer postocular setae slightly longer than the diameter of an eye facet, dorsum of head with weak granular area on integument. Pronotum trapezoidal, with widely spaced transverse lines of sculpture on anterior and posterior thirds; three pairs of small posteromarginal setae, two pairs of posteroangular setae, but only inner pair elongate ( Fig. 3 ). Prosternum with basantra absent; ferna thin, elongated and wide apart; prospinasternum transverse. Fore femora enlarged ( Fig. 3 ), fore tibia with small tooth-like tubercle near inner apex, fore tarsal pulvillus with terminal claw. Mesonotum partially fused to metanotum, both with transverse lines of sculpture; mesonotal paired campaniform sensilla near anterior margin, and metanotal sensilla localized at posterior margin of the sclerite; all meso- and metanotal setae small, scarcely 6 microns ( Fig. 7 ). Stigmata on meso and metathorax enlarged ( Fig. 5 ). Abdominal tergites with several lines of sculpture and with setal pair S2 arising far away from S1, either midway between setae S1 and S3 or close to S3 ( Fig. 8 ); on IX S2 is slightly longer than S1 and S3; paired trichobothria not present on tergite X ( Fig. 9 ). Abdominal sternite VIII with paired lobes, each bearing two setae; ovipositor reduced, posterior valves with weak serration.

Measurements (holotype female in microns). Body (distended) length about 1200 (1025–1220). Head, length 140; width 105. Pronotum, length 153; width 178. Hind tibia length 118; hind tarsus length 47; width 25. Antennal segments I–VIII length (width), 20 (35), 38 (30), 40 (25), 43 (22), 38 (18), 38 (18), 35 (18), 50 (15), respectively.

Male aptera. Similar to females (described above) except males exhibit an extensive, strong granular area on the head posterior of ocellar setae II, eye facets reduced, fore tibia with a large tooth ( Fig. 6 ) and fore femora enlarged. Measurements of male specimens (in microns), habitus 921–1138; antenna 199–247; head, length 97, width 65; head and mouth cone, length 124–136; pronotum, length 109–112, width 139–149; head and pronotum length 211–224.

Material examined. Holotype female BRAZIL: Rio Grande do Sul state: Porto Alegre (30º03’59”S, 51º07’15”W), on dead twigs, 28.ii.2011, A. Cavalleri, deposited in UFRGS, Porto Alegre.

Paratypes: Apterous females and males deposited at USNM and labelled as Merothrips mirus : BRAZIL: Rio de Janeiro state: Petrópolis , 1 female, on branches of pear defoliated by ants, 11.v.1948, J.D. Hood; Santa Catarina state: Nova Teutônia [District of Seara] , 3 females (labelled as ‘topotypic’), on dry branches, 02.i.1949, 13.i.1949 and 01.ii.1949, F. Plaumann; São Paulo state: Salesópolis, Boracéa , 1 female, on Andropogon , 08.vi.1948; 6 females and 1 male, on dead branches, 06.vi.1948; 5 females and 1 male, on dead branches, 07.vi.1948; 2 females and 1 male, on dead branches, 08.vi.1948, J.D. Hood; São Carlos , 4 females, on legume, 14.vi.1948; 1 female, on Orange trees, 21.vi.1950, J.D. Hood. Deposited at BMNH: São Carlos , 1 female, on grass, 14.vi.1948, J.D. Hood. Deposited at UFRGS: BRAZIL: Rio Grande do Sul state: Porto Alegre (30º04’01”S, 51º07’15”W) , 5 females on dead twigs, 11.ii.2011, 14.ii.2011, 28.ii.2011 and 03.iii.2011, A. Cavalleri; São Francisco de Paula , Pró-Mata (29°28’35”S 50°10’00”W) , 2 females on Tibouchina branches, 06.ix.2013, A. Cavalleri.

Figures

FIGURES 2–9. Merothrips meridionalis. (2) Female; (3) Female head & pronotum; (4) Antenna; (5) Spiracular area of pterothorax; (6) Male fore leg; (7) Female meso & metanotum; (8) Female tergites IV–VI; (9) Female tergites VIII–X.