Valan, Miroslav, Sychra, Oldrich & Literak, Ivan, 2016, Redescriptions and new host records of chewing lice of the genus Ricinus (Phthiraptera: Ricinidae) from the Neotropical Region, Zootaxa 4154 (2), pp. 179-189: 182-184

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Ricinus  sp.

( Figs 7–11View FIGURES 7 – 11, 20View FIGURES 19 – 21, Table 1)

Host. Corythopis delalandi (Lesson, 1831)  —Southern antpipit ( Passeriformes  : Tyrannidae  )

Locality. Kanguery Biological Station , San Rafael National Park, Paraguay (26°30´ S, 55°47´ W, 183 m a.s.l.)GoogleMaps 

Diagnosis. This Ricinus  species belongs to the marginatus  species-group by having three nodi, frontal margin not continuous with lateral margin, monomorphic mandibles without fingerlike articulation, and without evident ovoid sclerite. However, these females are distinguishable from females of all other species of the marginatus  species-group by the presence of 2 lateral, short equally long setae on tergites II –VIII. Also, they differ from females of R. dalgleishi  , R. emersoni  , R. flavicans  , R. marginatus  , R. pallens  and R. seiuri  by the absence of a6 setae. Unlike most species of the marginatus  species-group, which have 14 pairs of setae on the labium, our specimens have 12 pairs of labial setae; therefore, this feature separates them from R. dalgleishi  , R. dendroicae  , R. emersoni  , R. flavicans  , R. marginatus  , R. pallens  , R. picturatus  and R. seiuri  . Within the marginatus  species-group, R. frenatus  is the only species with long a1 seta and antennal lappets composed of 6 setae, compared to 12 – 13 setae in our specimens. Considerably smaller antennal lappets are also present in R. polioptilus  , which in addition has w series composed of 7 setae compared to our specimens which have only 5 setae.

Description. Head spatulate with straight lateral margins. Frons narrowly convex; lateral margins nearly parallel, not continuous with head lateral margin. Temple apices arcuate, not hooked outside. Occipital margin with concavity. Eyes not evident or slightly raised. Transverse carina present, convex. Lunar nodi absent, tentorial nodi present. Mandibles monomorphic, blades long, thin and sharp needle-like, tips not notched; galea not evident; basal lobe without finger-like process. Maxillary plates straight, narrow, lintel-like; pigment pattern present; palpi geniculate, not reaching the margin of head. Ovoid sclerite not evident. Gula with 1–2 pairs of setae; top of gular plate sclerite truncate; medial part with concavity; posterior projections present, directing posteriorly. Anterior margin of labium concave.

The cf series composed of 10 setae; df series present; f1 evidently longer than f2; a1 far shorter than m4; with one associated sensilla; a3 absent; a4 present; a6 absent; m1–m3 equal; m2 off the marginal carinae; m4 evidently longer than pa. Labium with 12 pairs of setae. Mental setae positioned laterally to each other. Mental setae shorter than maxillary. Preantennal setae strongly spinose. Setae along the antennal lappets (11–)12–13(–14). Four to 5 spinose, subequal postocular setae.

Thorax. Prothorax barrel-shaped; anterior margin distinctly concave; lateral margins not notched; posterior margin concave. Posterolateral angles of prothorax evidently rounded. Prosternal sclerites thick, parallel, joined. Anterior margin of sternal plate rounded, with lateral depression and posterior angles acute. L3 absent; L6 present; L5 nearly equal to L4 and L6; L9 shorter than L7 and L8; c4 present; c1 twice or more longer than c2; c2 pilose; c3 and c4 nearly equal; w series composed of 5 setae; anterior setae all nearly equal. Long sternal setae situated medially on pterothorax 2; q series composed of 2 spines; q2 strongly spinose; q2 not shorter than w series; b1 evidently shorter than b2. Coxa I with 2 tactile setae; femur I with 2 tactile setae; femur II and III without tactile setae.

Abdomen. Lateral margin of abdomen convex. Segment IX nearly equal to VIII. Pleural nodi on segment IX present, relatively wide, margins smooth; lateral part of abdominal pleurites heavily pigmented. Second ventral pleurite with two setae; II vps  1–2 large spinose; III vps  1–2 large spinose; III vps  3 large spine; IV vps  1 large spine; IV vps  2 long pilose; IV vps  3 large spine; V vps  1,3 small spine; VI vps  1,3 small spine; VII vps  1,3 small spine; VIII vps  1,3 small spine. Two pairs of setae on tergite VIII. Sternolateral setae equal to sternocentral on sternites II –VI. Vulva with 8–9 setae. Abdominal segment IX with 2 long terminal setae.

Dimensions. Female (n = 2). Head length 0.72–0.75; width 0.61–0.64; head index 117–118. Labrum width 0.34–0.35. Prothoracic length 0.35–0.36; width 0.60–0.61; ratio 0.58–0.59. Distance between prosternal setae 0.070–0.076. Abdominal width 0.91–0.94. Total length 3.10–3.20. Ratio of total length and abdomen width 3.40– 3.41.

Material examined. Ex Corythopis delalandi (Lesson, 1831)  Southern Antpipit ( Passeriformes  : Tyrannidae  ): 2♀, Kanguery Biological Station, San Rafael National Park, Paraguay (26°30´S, 55°47´W, 183 m a.s.l.), 20 Aug. 2012, I. Literak, slide PG107 [also 2N in alcohol].GoogleMaps 

Remarks. This is the first record of Ricinus  lice from Corythopis delalandi  . Although our specimens are distinguishable from females of all other species belonging to the marginatus  species-group, we have decided against naming them as a new species until males are collected and examined.