Dolops carvalhoi Lemos de Castro, 1949

Tavares, Luiz E. R., 2017, A new species of Argulus (Crustacea, Branchiura, Argulidae) from the skin of catfish, with new records of branchiurans from wild fish in the Brazilian Pantanal wetland, Zootaxa 4320 (3), pp. 447-469 : 462-464

Dolops carvalhoi Lemos de Castro, 1949

( Figure 10 )

D. carvalhoi : LEMOS DE CASTRO (1949): 4–6, fIGS. 9–20, 23–25; Dolops geayi BOUVIER, 1897: IN PART WEIbEZAHN & CObO (1964): 123, PL. I–II; D. carvalhoi : LEMOS DE CASTRO (1985): 12, 57–59; THATcHER (2006): 394, 396, 399.

Type host. Rhaphiodon vulpinus Agassiz, 1829 (Lemos de Castro 1949)

Type locality. Confluence between Kuluene and Xingu Rivers, state of Mato Grosso, Brasil (Lemos de Castro 1949)

Other hosts and localities. R. vulpinus , C. macropomum , the clupeiform Pellona castelnaeana Valenciennes, 1847 , P. fasciatum , P. tigrinum , Phractocephalus hemiliopterus (Bloch & Schneider, 1801) , Janauacá Lake, state of Amazonas, Brazil ( Malta & Varella 1983); P. nattereri , Serrasalmus spilopleura Kner, 1858 , S. marginatus, Brazilian Pantanal wetland, state of Mato Grosso do Sul, Brazil (Carvalho et al. 2003); P. nattereri, Araguaia River Basin , state of Goiás, Brazil (Carvalho et al. 2004); P. fasciatum (Linnaeus, 1766) , P. tigrinum, Ichilo River , Bolivia (Mamani et al. 2004).

Material deposited. 10 vouchers: 1 adult male ZUEC-CRU 3505, 4 July 2008, 1 adult female ZUEC-CRU 3506, 1 adult female INPA 2312, 8 July 2008, 1 adult male ZUEC-CRU 3503, 1 adult female MZUSP 36232, 8 July 2009, in ethanol 70%, Pseudoplatystoma corruscans , skin; 1 adult female ZUEC-CRU 3502, 1 adult female INPA 2313, in ethanol 70%, 8 July 2009, Pseudoplatystoma reticulatum , skin; 1 adult female ZUEC-CRU 3507 , in ethanol 70%, 8 July 2008, Zungaro zungaro, skin; 1 immature female INPA 2314 , in Hoyer’s medium, 1 immature female ZUEC-CRU 3404 , 8 July 2009, skin, Salminus brasiliensis ; all from Cuiabá River, Parque Nacional do Pantanal Matogrossense, Mato Grosso, Brazil (17°49′37.77″ S, 57°22′53.38”W) .

Measurements. Based on 3 males and 8 females. Total length (mm) 5.2 (4.2–6.1, n = 2) in males, 7.4 (5–11.1) in females. Carapace length 3.4 (2.7–4.1, n = 2) in males, 5.1 (3.6–7.7) in females; maximum carapace width 4.6 (3.2–6, n = 2) in males, 6 (4.3–8.5) in females. Carapace posterior sinus length 1 (0.7–1.2; n = 2) in males, 1.7 (1– 2.5) in females; width 1.2 (0.9–1.6, n = 2) in males, 2 (1.5–3) in females. Cephalothorax length 2 (1.5–2.9) in males, 3.2 (1.4–5.2) in females; anterior width 2 (1.6–2.5) in males, 3.5 (2.3–7) in females. Abdomen length 2.3 (1.5–3.1, n = 2) in males, 2.1 (1.5–2.9) in females; width 1.2 (1.1–1.3, n = 2) in males, 1.8 (1.3–2.4) in females. Abdomen posterior sinus length 1.9 (0.9–2.8, n = 2) in males, 1.4 (0.8–2) in females; width 0.8 (0.3–1.25, n = 2) in males, 0.7 (0.15–1). Eyes diameter (µm) 225 left and 200 right in one male, 336 (250–450, n = 7), left 332 (250– 425, n = 7) right in female; transverse distance between eyes (µm) 725 in one male, 1461 (1050–2000, n = 7) in female. First maxillae length 1.1 (0.8–1.4) left and 1.1 (0.7–1.5) right in males, 1.1 (0.7––1.7) left and 1 (0.7–1.6) right in females; Hook of the first maxillae length (µm) 715 (413–1250) left and 725 (431–1300) right in males, 498 (263–658) left and 452 (273–712.5) in females. Seta-like structure length (µm) 186 (140–250) left and 205 (114–275) right in males, 194 (75–250, n = 7) left and 160 (76.5–310, n = 7) right in females.

Remarks. The specimens of D. carvalhoi that we observed had a pyriform carapace, which was wider than it was long, and, more frequently, covered all the legs in both males and females. There are no spines on the ventral surface of the carapace of this species (Lemos de Castro 1949) and the testis are bilobate. The presence of these characteristics makes its morphological relationship with D. longicauda , D. geayi and D. nana Lemos de Castro, 1950 ( Bouvier 1899; Heller 1857; Lemos de Castro 1950) narrower.

In his description of D. nana, Lemos de Castro (1950) stated that there are two spines plus a lobe on the base of the second maxillae. The author also exhibited legs without flagella in his drawings. Nevertheless, specimens of D. carvalhoi , D. longicauda and D. geayi have three spines on the base of the second maxillae ( Fig. 10D ) and flagella in at least the first and second legs.

Males and females of D. carvalhoi have flagella on the first three legs (Lemos de Castro 1949). This, distinguishes them from specimens of D. geayi , which have flagella on just the first two pairs of legs ( Bouvier 1899; Ringuelet 1943). Lemos de Castro (1949) said that the second pairs of flagella of D. carvalhoi are the largest and the third pairs smaller. However, in his drawings, he showed the first pair of flagella as smaller. In the specimens examined in the present study, we saw that only males exhibited smaller flagella on the third legs, whereas in D. longicauda , both males and females exhibited smaller flagella on the third legs.

The spines on the base of the second maxillae are similar in D. carvalhoi and D. longicauda . The morphology of the anal papillae of the female ( Fig. 10B , 11F ) is also similar for these two species. Furthermore, a seta-like structure on the hook of the second maxillae without spines is present in both species ( Fig. 10C , 11E ). Morphologically speaking, therefore, the color pattern (bluish or greenish in D. longicauda , brownish in D. carvalhoi ); the flagella on the third legs of females; and especially the abdomen length (smaller in D. carvalhoi : 27% and 44%, of female and male total length, respectively; larger in D. longicauda : 64% of total length) are important characteristics for distinguishing D. carvalhoi from D. longicauda . Yet, there are four to six multi-digit scales on the mandibles of D. carvalhoi , many of which are present on the legs ( Fig. 10A ), while in D. longicauda there are no scales on any part of it body.

Figures

FIGURE 10. Dolops carvalhoi. A ScALES (ARROW) Of fOURTH LEG Of fEMALE B ANAL PAPILLAE Of fEMALE C SETA-LIKE STRUcTURE (ARROW) IN THE fIRST MAXILLAE Of THE MALE D SPINES Of SEcOND MAXILLAE AND THORAcIc SPINE Of MALE. ScALE bAR = A 0,15 MM, B 0.5 MM, C – D 0.25 MM

FIGURE 11. FEMALE Of Dolops longicauda. A fIRST (A 1) AND SEcOND (A 2) B MOUTH TUbE (LAbI: LAbIUM; LAbR: LAbRUM; M: MANDIbLES) C SEcOND MAXILLAE (SE: SENSILLUM; S 1 – 4: SEGMENTS) D fIfTH (S 5) AND SIXTH (S 6) SEGMENTS Of THE SEcOND MAXILLAE ANTENNAE E SETA-LIKE STRUcTURE (SLS) IN THE fIRTS MAXILLAE F ANAL PAPILLAE (VENTRAL VIEW). ScALE bAR = A 0.5 MM, B – C 0.25 MM, D – F 0.1 MM