Dennyus (Dennyus) pichorimi, Valim, 2013

Valim, Michel P., 2013, Parasitic On Swifts (Aves, Apodiformes, Apodidae) In Brazil, Papéis Avulsos de Zoologia (São Paulo) 53 (30), pp. 415-429 : 415-429

Dennyus (Dennyus) pichorimi sp. nov.

( Figs. 1-9 )

Type host: Streptoprocne biscutata seridoensis Sick, 1991 – Biscutate Swift ( Apodiformes : Apodidae )

Holotype: Male ( MZUSP #2495 ), ex Streptoprocne biscutata seridoensis , BRAZIL: Rio Grande do Norte, Acari, Serra do Bico da Arara , Fazenda Ingá [06°28’40”S; 36°36’05”W], 26.VIII.2007, M. Pichorim coll.

Paratype: 1 Female ( MZUSP #2496 ), same data as the holotype but collected from a different host individual .

Etymology: The species epithet is a noun in the genitive case dedicated to the Brazilian ornithologist Mauro Pichorim, in recognition of his efforts collecting bird ectoparasites and for his long-term studies on Biscutate Swift in Brazil.

Diagnosis: Dennyus (Dennyus) pichorimi is morphologically close to a group of four species which have: (1) prosternal plate with numerous short and thickened setae set in the center of the plate (not only on its anterior half), plus an antero-lateral pair of long and thin setae ( Fig. 6 ); (2) lateral margin of the pronotum with two short spine-like setae and one long thin seta (rather than all three short spine-like setae) ( Figs. 1 and 3 ); and (3) gular plate mostly pale with a U-shaped band of sclerotization ( Fig. 6 ). The type hosts and localities are for these species: D. (D.) brunneitorques Carriker, 1954 (ex Streptoprocne rutila brunneitorques (Lafresnaye) , Peru); D. (D.) rotundocapitis Carriker, 1954 (ex Streptoprocne zonaris albicincta (Cabanis) , Colombia); D. (D.) semicollaris Price & Beer, 1962 (ex Streptoprocne semicollaris (DeSaussure) , Mexico); and D. (D.) spininotus Carriker, 1954 (ex Cypseloides fumigatus (Streubel) , Colombia).

Dennyus (D.) pichorimi is easily distinguished from the species with known males ( D. (D.) rotundocapitis and D. (D.) semicollaris ) by the shape of its parameres ( Fig. 7 ). The slender parameres of D. (D.) rotundocapitis are quite distinct from the robust parameres of D. (D.) pichorimi ( Figs. 1, 2 , 7 ). In the other known species with robust parameres ( D. (D.) semicollaris ), these are not curved as in the new species ( Fig. 7 ). Also the sternal plate II of D. (D.) pichorimi is medially divided ( Fig. 6 ), as in D. (D.) semicollaris and D. (D.) rotundocapitis . The genital sclerite of D. (D.) pichorimi is also distinctive and unique ( Fig. 8 ).

The female of D. (D.) pichorimi has a sclerotized median sternal plate on segments I and II ( Fig. 6 ), but these plates are indistinct in females of D. (D.) spininotus and D. (D.) brunneitorques . The head shape of the new species is similar to that of D. (D.) spininotus , both with truncated and angulated temporal regions ( Fig. 5 ), while those of D. (D.) brunneitorques are distinctly rounded. However, D. (D.) spininotus has short spine-like setae on the posterior margin of abdominal tergites, while those setae in D. (D.) pichorimi are slightly thick but normal in shape. Also, D. (D.) spininotus has more metanotal setae (28 vs. 16 in D. (D.) pichorimi ) and tergal setae on the first three abdominal segments (30 on I; 36 on II; 38 on III vs. 24, 24, 26, respectively in D. (D.) pichorimi ). Furthermore, D. (D.) pichorimi is one of the largest within Dennyus (Dennyus) , with over 3 mm in TL.

Both sexes of D. (D.) pichorimi can be promptly distinguished from the new species described below by the number of outer dorsal (10 vs. 3 and 7, in D. (D.) pascoliae and D. (D.) malagonensis , respectively) and ventral (5 vs. 4 in D. (D.) pascoliae ) setae on first tibia.

Description

Male: Habitus dorsal and ventral as in Figs. 1-2 , respectively. Head approximately two times wider than long, cephalic index 0.58 (length/width). Preantennal margin smoothly rounded, temporal and occipital margins distinctly angulated (as in Fig. 5 ). Dorsal head seta 5 (dhs5) short and slender; dhs14, dhs28, and one unnamed setae between the dhs29 and dhs31 short and spiniform. Labial setae 5 (ls5) 0.28 long (as in Fig. 6 ). Gular plate with 9+7 setae.

First tibia with 5 outer lateral ventral and 10 dorsal setae. Prosternal plate with 15 short setae, plus an anterior pair of long setae; mesosternal plate with 23 setae; metasternal plate with 31 setae. Femoral brush III with 59-60 setae. Metapleura with 3-4 long setae on each side; metathorax with 15 setae on posterior margin; median anterior metanotal setae transversely aligned with respect to anterior lateral setae.

Tergal setae, posterior row: I, 19; II, 22; III, 22; IV, 25; V, 28; VI, 24; VII, 24; VIII, 19. Setae on tergites II-VII becoming progressively longer towards the posterior segments, with two or three shorter setae between the longer ones, which reach across the following segment (3+3 on each segment, most of them missing in type series). Relative lengths of median long setae on tergite IV, about 3-6 longer than others of the same segment (0.06-0.10 long); length of longest median setae 0.28-0.36. Sternite I with a pair of long setae (one on each latero-posterior side) and 13 short anterior setae. Sternal plate II medially divided (as in Fig. 6 ). Sternal setae, posterior row: II, 15 ; III, 18; IV, 21; V, 12; VI, 11; VII, 6. Anterior sternal rows: II, 35 ; III, 41; IV, 39; V, 26; VI, 25; VII, 8. Sternites I-VII with two irregular anterior rows of setae; sternites V-VII with a large brush of setae on their lateral margins, less distinct in the posterior segments. Sternal brush setae (left and right, respectively) : V, 35+35; VI, 47+43; VII, 26+24 ( Fig. 2 ). Anterior and posterior setae in brush on sternite VI similar to each other. Sternite VIII with a single row of 10 medium long setae. Lateral plates wide and heavily sclerotized, with 8-11 setae on the posterior margin of segments III-VII (4-5 outermost setae thin and long, nearly of the same length of respective postspiracular setae); dorsal portion of pleurites II-VIII with characteristic incrassations ( Fig. 1 ) .

Genitalia as in Fig. 7 , with robust parameres inwardly curved and genital sclerite with toothed apex ( Fig. 8 ).

Measurements (n = 1): TW, 0.93; PoW, 0.62; HL, 0.54; PW, 0.53; PrL, 0.29; PrW, 0.21; MW, 0.94;

FeIIL, 0.50; FeIIIL, 0.65; AL, 1.76; AW, 1.28; GL, 1.29; PaL, 0.38; GSL, 0.34; TL, 3.03.

Female: Habitus dorsal and ventral as in Figs. 3-4 , respectively. Similar to the male, except in dimensions and morphology of terminalia. Head as in the male, cephalic index 0.58. Labial setae 5 (ls5) 0.36 long ( Fig. 6 ). Gular plate with 8+9 setae.

First tibia with 5 and 10 outer lateral ventral and dorsal setae, respectively. Prosternal plate with 13 short spine-like setae, plus an anterior pair of long setae; mesosternal plate with 20 setae; metasternal plate with 24 setae ( Fig. 6 ). Femoral brush III with 54-55 setae. Metapleura with 2-3 long setae on each side; metathorax with 16 setae on its posterior margin.

Tergal setae with only a posterior row: I, 24; II, 24; III, 26; IV, 24; V, 23; VI, 24; VII, 20; VIII, 17. Sternite I with a pair of long setae, one on each latero-posterior side, and 10 short anterior setae ( Fig. 6 ). Sternal plate II medially divided ( Fig. 6 ). Sternal setae, posterior row: II, 16; III, 18; IV, 19; V, 13; VI, 11; VII, 4. Anterior sternal rows: II, 24; III, 32; IV, 41; V, 24; VI, 28; VII, 15. Sternal brush setae: V, 41+38; VI, 44+42; VII, 22+20 ( Fig. 4 ). Subgenital plate without medio-anterior setae; with short (0.10-0.12) lateral marginal setae (lms, Fig. 9 ) on subgenital plate; roughly similar in size and shape to the median marginal setae (0.12-0.20 long) (mms, Fig. 9 ), with 4 on each postero-lateral side. Ventral anal fringe with 85 and dorsal anal fringe with 89 setae; without any setae anterior to anal fringe. A regular row of 28 setae on vulvar margin ( Fig. 9 ).

Measurements (n = 1): TW, 0.95; PoW, 0.63; HL, 0.55; PW, 0.54; PrL, 0.31; PrW, 0.21; MW, 0.98; FeIIL, 0.52; FeIIIL, 0.65-0.67; AL, 1.93; AW, 1.35; AnW, 0.52; TL, 3.29.

Remarks

Price et al. (2003: 284) did not list chewing lice from either subspecies of Streptoprocne biscutata . The nominal subspecies occurs from SE Brazil to Paraguay and NE Argentina, while S. b. seridoensis – the type host of the new louse species described here – occurs in NE Brazil only. There are highly supported morphological differences among species of Dennyus from different host subspecies (e.g., Aerodramus brevirostris (Horsfield) , Collocalia linchi Horsfield & Moore ) ( Clayton et al., 1996). Therefore, assuming the high host-specificity between Dennyus species and their hosts (see Tompkins & Clayton, 1999). D. (D.) pichorimi could be an endemic Brazilian species. Studies of louse samples from the nominal subspecies of Streptoprocne biscutata are necessary to confirm or otherwise falsify such endemicity.

Figures

FIGURES 1‑4: Dennyus (D.) pichorimi sp. nov.: male holotype in dorsal (1) and ventral (2) views; female paratype in dorsal (3) and ventral (4) views. Scale bars = 0.2 mm

FIGURES 5‑9: Dennyus (D.) pichorimi sp. nov.: female head, in dorsal view (5); female gular, thoracic sternites, and abdominal sternites I and II (6); male genitalia (7); detail of the male genital sclerite (8); female subgenital, vulvar and ventral anal setae (9). lms = lateral marginal setae; mms = median marginal setae (both on the subgenital plate); gul = gular plate; pro = prosternal plate; mes = mesosternal plate; met = metasternal plate; strI = sternite I; strII = sternite II. Scale bars = 0.1 mm (Figs. 5-7, 9); = 0.05 mm (Fig. 8).