Culicoides castelloni sp . nov . from the Brazilian Amazon Region with a revision of the reticulatus species group ( Diptera , Ceratopogonidae )

A new species of the reticulatus species group, C. castelloni Santarém and Felippe-Bauer, is described and illustrated based on female specimens from the state of Amazonas, Brazil. A systematic key, wing photographs and table with numerical characters of females and a synopsis of 24 species of the Culicoides reticulatus group are presented. This paper presents further new records for seven species of the reticulatus group.


INTRODUCTION
The reticulatus species group was proposed by Wirth and Blanton (1959) from nine species of the subgenus Oecacta Poey, taking into account the similarity of the pattern of the pale and dark wing spots and others extra alar characters.The fragility of this proposition based on characters also founded in others Culicoides species groups, promoted, in the following years, placements and exclusion of species in the reticulatus species group.Wirth et al. (1988) included in the reticulatus species group 15 species and considered this group out of the subgenus Oecacta and others previously established subgenus of Culicoides.
This consideration was followed by Borkent andSpinelli (2000, 2007).Recently, Felippe-Bauer et al. (2010) described Culicoides kuripako Felippe-Bauer from the Brazilian Amazon, and Santarém et al. (2014) redescribed C. reticulatus Lutz and recognized seven species very similar to C. reticulatus Lutz on several morphological aspects and included them in the reticulatus species group.Currently, the reticulatus species group is known to contain 23 species well distributed in the neotropics and despite the uncertainty of the monophyly of the group, we maintain this group of species, until further phylogenetic studies are made.
In the present paper, we describe and illustrate a new species from the state of Amazonas, Brazil, The specimens were preserved in alcohol 70% or slide mounted.The general terminology used is that employed in papers on Culicoides by Wirth andBlanton (1959, 1973) for Panama and the Amazon Basin, the atlas of wing photographs of Neotropical species by Wirth et al. (1988) and the Manual of Central America Diptera (Brown et al. 2009).Meristic informations were updated based on specimens deposited in the above mentioned collections and on data cited in the literature, except for Culicoides macrostigma Wirth and Blanton and C. martinezi Wirth and Blanton whose data were taken from specific literature, because we didn`t obtain specimens for study.All measurements are in micrometres, except those of the wings which are in millimeters.
The new species described herein was collected by CDC light trap in forest areas from Rio Pardo, municipality of Presidente Figueireido, state of Amazonas, Brazil.The specimen was mounted in phenol-balsam in the manner described by Wirth and Marston (1968).The diagnostic characters were illustrated using a camera Moticam 2300 attached to a Nikon Eclipse E-200 microscope, and the figures and plates were prepared using Photoshop GIMP Portable, except C. kuscheli Wirth and Blanton, C. macrostigma and C. martinezi, whose photos of the wings were taken from Wirth et al. (1988) with permission of editors.The new species was deposited in CCER.Diagnosis: Female: r 3 with five pale spots in the proximal ½ of cell; m 1 with two pale spots, the distal one far from wing margin; AR 0.72-0.76;proboscis short, P/H ratio 0.61-0.70.Male: sternite 9 with slightly perceptible posteromedial excavation; aedeagus with basal arch extending to 0.3 of total length; parameres without ventral lobes, distal portion curved, apex flattened.
Etymology: This species is named in honor of Dr. Eloy Guillermo Castellón for his contributions on Culicoides studies in the Brazilian Amazon Region.
Thorax.Dark brown (Fig. 27).Prominent pattern of yellowish patches well defined; pale humeral depressions present.Scutum with two parallel, longitudinal, admedian pale spots, anterior to the prescutellar depression; lateral portion dark; pale prescutellar depressions present; scutellum and postscutellum brown.Wing (Fig. 3) with contrasting pattern of pale spots large, separated and rounded: second radial cell including dark spot; pale spot over R-M extending from M 1 to the costal margin; r 3 with four pale spots: first, between the second radial cell and M 1 ; second, poststigmatic, extending behind second radial cell, abutting wing margin; third, in the middle of cell; fourth, distal pale spot slightly reaching wing margin; m 1 with two pale spots, the distal one far from wing margin and similar to proximal one; m 2 with four pale spots: one proximal, near CuA, second and third between the medial and mediocubital forks, and a distal one not reaching wing margin; cua 1 with a pale spot in the middle of cell; anal cell with a basal pale area and two distal pale spots, one near mediocubital fork, remaining one near wing margin; wing base with a pale spot on M; M 1 , M 2 and CuA 1 with pale apex; macrotrichia scarce; wing length 0.83 (n = 1) mm; breadth 0.40 (n = 1) mm; costal ratio 0.64 (n = 1).Halter pale.Legs (Fig. 30) brown; fore and mid femora with subapical pale bands; tibiae with subbasal pale bands; hind tibia pale apically; hind tibial comb with six spines, the second nearest the spur longest.
Male.Unknown Distribution and bionomics: This species is restricted to the state of Amazonas.It is associated with forest areas.
Taxonomic notes: Culicoides castelloni is the only species of reticulatus species group with sensilla coeloconica on flagellomeres 1, 9-13 and a tibial comb with six spines (sensilla coeloconica 1,5-8 or 1,6-8 and tibial comb with 4-5 spines in other species of the group).It has a long third palpal segment (PR 4.2) with a small, rudimentary sensory pit (PR 1.6-3.2 with variable sensory pit, in other species of the group).The female of C. castelloni has similar wing pattern to C. reticulatus Lutz, but it can be distinguished by the characters described above and by the presence of two parallel, longitudinal, admedian pale spots, anterior to the prescutellar depression (with four median anterior yellowish spots arranged as a leaf clover in C. reticulatus Lutz).Diagnosis: Female: r 3 with four pale spots; m 1 with two pale spots, the distal one far from wing margin; scuttum with four median anterior yellowish spots arranged as a leaf clover; 3rd segment of palpus with two well-defined sensory pits on distal 2/3 of the segment, the basal one ventrally and the distal one laterally; PR 2.5-2.8.Male: tergite 9 long, tapering, with very short and blunt apicolateral processes, with distinct posteromedial notch; parameres stem sinuous and swollen in median portion ending in ventral lobes; basal arch of aedeagus extending 2/3 of total length.

C. diplus
Distribution: Panama and Colombia C. fittkaui Wirth and Blanton (Fig. 5, Table I Diagnosis: Female: Pale spots of the wing interconnected; r 3 with two pale spots; second radial cell with pale lumen; m 1 with two pale spots, the distal one reaching wing margin; eyes nearly contiguous; hind femur dark; proboscis short, P/H ratio 0.60-0.63.Male: sternite 9 with deep posteromedial excavation; aedeagus with basal arch extending from ½ of total length; parameres with large ventral lobes, apical portion with lateral fringe of spicules. Distribution: Brazil (Pará).Taxonomic notes: Wirth and Blanton (1973) described and illustrated the eyes of this species as contiguous in lower portion.The authors not mentioned the presence of pale spots in hind femur, but in the figure 8g, the hind femur is illustrated with large subapical pale band.Analyzing the female holotype deposited in ILMD, we observed that the eyes are narrowly separated in all extension and the hind femur is entirely dark, corroborating the original description.Diagnosis: Female: r 3 with four pale spots; m 1 with two pale spots, the distal one far from wing margin; single pale spot over R-M; anal cell with two distal pale spots, one near mediocubital fork and other not reaching wing margin; scutum with four median anterior yellowish spots arranged as a leaf clover; 3 rd segment of palpus with a small, shallow, rounded, sensory pit in middle portion; PR 2.6-3.2;long proboscis; two unequal spermathecae.

Male: Unknown
Distribution: Brazil (Rio de Janeiro) C. forattinii Ortiz (Fig. 7 Diagnosis: Female: Pale spots of the wing interconnected; r 3 with two pale spots; m 1 with two pale spots, the distal one reaching wing margin; second radial cell short, with dark lumen; hind femur dark; proboscis short, P/H ratio 0.71-0.79.Male: sternite 9 with shallow posteromedial excavation; aedeagus with basal arch extending to 0.6 of total length; parameres with a strong ventral swelling on proximal portion of stem, distal portion with filamentous tip with fringing spines. Distribution: Brazil (Pará).
C. guyanensis Floch and Abonnenc (Fig. 10, Table I Diagnosis: Female: r 3 with five pale spots, the distal three distributed as a triangle; m 1 with three pale spots, the distal one reaching wing margin; proboscis short, P/H ratio 0.75-0.87;sensilla coeloconica on flagellomeres 1,4-8.Male: sternite 9 with shallow posteromedial excavation; aedeagus with basal arch extending to ½ of total length, distal portion with a long, slender median lobe and a pair of slender, pointed, lateral lobes; parameres with basal knob bearing a slender anterior process, stem stout and tapering in a slender simple tip.
New records: One male, HONDURAS, Barbareta Island, 16°26'N 86°07'W, light trap, G.M. Diagnosis: Female: Pale spots of the wing interconnected; r 3 with two pale spots, postigmatic pale spot inverted L-shaped, isolating a dark spot behind second radial cell; m 1 with two pale spots, the distal one reaching wing margin; CuA 1 and CuA 2 pale.Male: sternite 9 with deep posteromedial excavation; aedeagus with basal arch extending to ½ of total length; parameres with ventral lobes, distal portion with lateral fringe of spicules.
Diagnosis: Female: r 3 with four pale spots on proximal ½ of cell; second radial cell 2.5x longer than first, with pale lumen; m 1 with two pale spots, the distal one far from wing margin; eyes contiguous; hind femur dark; AR 1.97; proboscis short, P/H ratio 0.55; mandible with 11 teeth.Male: sternite 9 with shallow posteromedial excavation, ventral membrane spiculate; aedeagus with basal arch extending to ½ of total length; parameres with basal knob bearing an elongate anterior process, without ventral lobes; distal portion bent laterally, ending abruptly.
Distribution: Costa Rica to Colombia.Diagnosis: Female: r 3 with six pale spots arranged in two sets of triangles, one near the second radial cell and other in distal portion; m 1 with three pale spots, the distal one not reaching wing margin; eyes broadly separated; mid and hind femur dark.Male: sternite 9 with shallow posteromedial excavation; aedeagus with basal arch extending to 0.75 of total length, distal portion with spiculate tip; parameres stout, with broad ventral lobes, distal portion with lateral fringe of spicules well developed.
Diagnosis: Female: Pale spots of the wing interconnected; r 3 with two pale spots, poststigmatic pale spot inverted L-shaped, isolating a dark spot behind second radial cell; m 1 with two pale spots, the distal one reaching wing margin; CuA 1 pale and CuA 2 dark.Male: sternite 9 with moderately deep posteromedial excavation, ventral membrane spiculate; aedeagus with basal arch extending to ½ of total length, distal portion spiculate; parameres sinuous without ventral lobes, distal portion with lateral fringe of spicules.

C. tricoloratus
Diagnosis: Female: r 3 with two pale spots; m 1 with two pale spots the distal one far from wing margin; CuA 1 dark, AR 0.84-1.02.Male: sternite 9 with shallow posteromedial excavation; aedeagus with basal arch extending to 0.75 of total length, distal portion flanked by a subapical pair of sclerotized lobes; parameres without ventral lobes, distal portion tapered to a subapical fringe of well developed spicules.
New records: Two females and one male, ECUADOR, Los Rios, Rio Palenque, "57 km N Quevedo", 1°01'S 79°27'W, UV light trap, J.S. Diagnosis: Female: r 3 with four pale spots; m 1 with two pale spots, the distal one far from wing margin; scutum with four median anterior yellowish spots arranged as a leaf clover; eyes separated by diameter of ½ ommatidium; palpus with shallow, rounded sensory pit in middle portion; PR 2.6-3.0 (n=6); proboscis long, P/H ratio 1.14-1.17.Male: parameres stem, slightly sinuous in median portion, without ventral lobes; basal arch of aedeagus extending ½ of total length.Distribution: Brazil (Pernambuco and Bahia).Diagnosis: Female: r 3 with three pale spots; m 1 with two pale spots, the distal one far from wing margin; halter dark; hind femur dark; mandible with 15-16 teeth.Male: sternite 9 with shallow posteromedial excavation; aedeagus with basal arch extending to 0.6 of total length; parameres with well-developed ventral lobes, distal portion with lateral fringe of spicules.
Distribution: Brazil (Rio de Janeiro and Santa Catarina).