Ricinus tanagraephilus Eichler, 1956

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 : 184-187

Ricinus tanagraephilus Eichler, 1956

( Figs 12–18 , 22–23, Table 1)

Ricinus tanagraephilus Eichler, 1956: 133 .

Ricinus tanagraephilus Eichler, 1956 ; Nelson 1972: 111. Species inquirendae. Ricinus tanagraephilus Eichler, 1956 ; Price et al. 2003: 251.

Type host. Euphonia laniirostris hypoxantha von Berlepsch & Taczanowski, 1884 —Thick-billed euphonia ( Passeriformes : Fringillidae )

Type locality. Peru.

Diagnosis. Ricinus tanagraephilus belongs to the subangulatus species-group ( Nelson 1972) by having lunar nodi, monomorphic mandibles, evident ovoid sclerite with pit-like depressions, and pattern on terminal tergite of female iIIi x iIIi, but can be distinguished from Ricinus subangulatus ( Carriker, 1903) , Ricinus complicatus Carriker, 1964 , Ricinus ramphoceli Nelson, 1972 and Ricinus volatiniae Nelson, 1972 by having setae a6 and 13 labial setae. Also, it differs from R. vireoensis and Ricinus wolfi Nelson, 1972 by having 3 setae on the parameres. Further, R. tanagraephilus differs from Ricinus subhastatus ( Durrant, 1906) by having setae a6, and inner setae on pleurites VI–VIII small and pilose.

Description. Head subconical, with straight lateral margins. Frons broadly convex; lateral margins divergent, not continuous with head lateral margin. Temple apices acute, hooked outside. Occipital margin nearly straight. Eyes not evident or slightly raised. Transverse carina present, convex. Lunar nodi present; tentorial nodi present, and lunar nodi nearly equal to tentorial. Mandibles monomorphic, blades long, thin and sharp needle-like, with tips notched; galea evident; basal lobe without finger-like process. Maxillary plates sausage-like; pigment pattern present; palpi geniculate, reaching the head margin. Ovoid sclerite evident, ornamentation deeply pitted. Gula with 2–3 pairs of setae; top of gular plate sclerite truncate; medial part without 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 two associated sensilla; a3 absent; a4 present; a6 present; m1–m3 equal; m2 off the marginal carinae; m4 evidently longer than pa. Labium with 13 pairs of setae. Mental setae positioned laterally to each other. Mental setae shorter than maxillary. Preantennal setae strongly spinose. Setae along the antennal lappets 11–13. Two spinose and subequal postocular setae.

Thorax. Prothorax hexagonal; anterior margin distinctly concave; lateral margins slightly notched; posterior margin concave. Posterolateral angles of prothorax evidently rounded. Prosternal sclerites thin, parallel, not joined. Anterior margin of sternal plate concave, without lateral depression; posterior angles straight. L3 present; L6 present; L5 larger than L4 and L6; L9 evidently shorter than L7 and L8; c4 present; c1 and c2 nearly equal; c2 spinose; c3 and c4 nearly equal; w series composed of 6 setae; anterior setae unequal. Long sternal setae situated medially on pterothorax 1; 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 with present tactile setae.

Abdomen. Lateral margin of abdomen nearly straight. Segment IX nearly equal to VIII. Pleural nodi on segment IX present; relatively wide; margins smooth; lateral part of abdominal pleurites lightly pigmented. Second ventral pleurite with 3 setae; II vps 1–3 large spinose; III vps 1–2 small spinose; III vps 3 small spine; IV vps 1 large spine; IV vps 2 long pilose; IV vps 3 large spine; V vps 1 small spine; V vps 3 small pilose; VI vps 1, 3 small pilose; VII vps 1, 3 small pilose; VIII vps 1 small pilose; VIII vps 3 small to medium pilose. Two pairs of setae on tergite VIII. Sternolateral setae not equal to sternocentral on sternites II–VI. Vulva with 11 setae. Abdominal segment IX with 2 long terminal setae.

Male genitalia symmetrical; basal plate not narrow anteriorly; lateral margin slightly concave. Parameres triangular, with blunt endings. Mesosomal plate pigmented, lightly pointed and without medial extension. Three setae on the distal tips of the parameres.

Dimensions. Female (n = 15). Head length 0.75–0.77; width 0.61–0.63; head index 120–124. Labrum width 0.30–0.32. Prothoracic length 0.37–0.38; width 0.58–0.59; ratio 0.63–0.66. Distance between prosternal setae 0.059–0.062. Abdominal width 1.01–1.05. Total length 3.70–3.78. Ratio of total length and abdomen width 3.60– 3.66.

Male (n = 1). Head length 0.70; head width 0.59; head index 119. Labrum width 0.29. Prothoracic length 0.34; width 0.53; ratio 0.64. Distance between prosternal setae 0.062. Abdominal width 0.84. Total length 3.325. Ratio of total length and abdomen width 3.96. Length of male genitalia 0.48; width of mesosomal plate 0.188.

Material examined. Holotype ♀, Perú, date unknown, von Koepcke Coll., slide WEC3066a ( ZMHU) . Non-types. Ex Euphonia laniirostris d'Orbigny & Lafresnaye, 1837: 1 ♂, 4♀, La Amistad Lodge , Las Tablas, Costa Rica (8°54’ N, 82°47’ W; 1300 m a.s.l.) 18–19 Aug. 2010, I. Literak, slides LT15a–b, LT65 [also 10♀, 9N in alcohol].

Remarks. Eichler’s (1956) brief description of R. tanagraephilus was based on one female only. Carriker (1964: 50) subsequently redescribed this species, but Nelson (1972: 111) examined the specimen from Euphonia laniirostris studied by Carriker (1964) and recognized it as a distorted specimen of R. marginatus . For that reason, Nelson (1972) designated R. tanagraephilus as a species inquirendae. We also examined Carriker’s specimen and we are able to confirm Nelson’s (1972) identification.

Although our samples originated from a different country than the type locality of R. tanagraephilus and, therefore, also from a different subspecies of E. laniirostris than the type host, our comparison against the holotype of this louse species allowed us to confirm that this is a distinct and valid species of Ricinus . Also, we record and describe the male of R. tanagraephilus for the first time.

Figures

FIGURES 12 – 18. Ricinus tanagraephilus: 12, dorso-ventral views of head. 13, dorso-ventral views of abdomen. 14, male genitalia. 15, mandibles. 16, ovoid sclerite. 17, labium. 18, ventro-dorsal views of thorax. Scale bars in mm. Note: Complete anal fringes are drawn as in Nelson (1972).