Ophiocordyceps camponoti-indiani Araújo, H.C. Evans & D.P. Hughes, 2015

Araújo, João P. M., Evans, Harry C., Geiser, David M., Mackay, William P. & Hughes, David P., 2015, Unravelling the diversity behind the Ophiocordyceps unilateralis (Ophiocordycipitaceae) complex: Three new species of zombie-ant fungi from the Brazilian Amazon, Phytotaxa 220 (3), pp. 224-238 : 232

Ophiocordyceps camponoti-indiani Araújo, H.C. Evans & D.P. Hughes , sp. nov. ( Fig.4 )IF 550745

Differs from other members of the O. unilateralis clade by the host (always Camponotus indianus ), ascospore morphology and germination. Hirsutella-b type, very long capilliconidiophores formed after ascospore germination. Several stromata (up to 12) and three ascomata commonly found, instead the typical single fruiting body of close related species.

Type: — BRAZIL. Amazonas: Parque Nacional do Viruá, 01˚ 42’ 25” N, 61˚ 10’ 24” W 200 m, 12 February 2012, on Camponotus (Tanaemyrmex) indianus Forel, J.P.M. Araújo & F. B. Baccaro V-25, ( INPA 261938, holotype!), FROST 90328, isotype!).

Mycelium aggregations arising from all inter-segmental membranes (sutures), ginger in color. Stromata multiple, arising from dorsal, right and left sides of pronotum, and leg joints, (1.5–) 8–10 (16) × 0.3–0.4 (–1) mm, ginger at the base becoming purplish-cream towards the apex. Ascomata produced only on the pronotal stromata, never from those on legs; lateral cushions, 1–4, hemispherical, chocolate to dark brown with age. Perithecia immersed to semi-erumpent, ovoid to flask-shaped, 230–310 × 120–175 μm, with a short, exposed neck. Asci 8-spored, hyaline, cylindrical (135–) 170 (–190) × 8.5 (–11.5) μm; cap prominent, 4.5 × 5 μm; Ascospores hyaline, thin-walled, cylindrical, (60–) 75 (–80) × (3.5–) 4.5 (–5), 5-septate, occasionally swollen, narrowing to acute tips at both ends.

Etymology: Named after the ant host, Camponotus indianus Forel.

Asexual-morph: —Hirsutella-like A type associated with the apical region of all stromata; phialides cylindrical to lageniform, 7.5 (–9.5) × 3.5 μm, tapering to a long hair-like neck, 6.5–11 μm in length, conidia not seen. Hirsutella-like C type (= H. sporodochialis - type) produced from ginger cushions (sporodochia) on legs and antennal joints: phialides hyaline and subulate at the base, robust; no conidia observed.

Germination process:—Ascospores germinated 48 h after release; typically, producing 2, rarely 3, hair-like capilliconidiophores, 120–130 μm in length; bearing a single terminal conidium, 13–14 μm biguttulate, fusoid, narrowing apically.

Habitat: —Brazilian Central Amazon (Parque Nacional do Viruá). Biting onto leaves, never twigs.

Additional specimens examined (paratypes): — BRAZIL. Parque Nacional do Viruá: Manaus, 01˚42’25” N, 61˚10’24” W, 200m elevation, 14 February 2012, Araújo, H.C. Evans & D.P. Hughes, A35 (INPA 261941, paratype!).

Figures

FIGURE 4. Ophiocordyceps camponoti-indiani a) Camponotus indianus biting into a leaf, several stromata arising from dorsal pronotum, mesonotum and leg joints, with a characteristic purplish coloration. a-1) lateral, fertile cushion (ascoma); a-2) Close up of the dead ant’s head showing the biting behavior. b) Section through ascoma showing perithecial arrangement (bar = 500 μm); c) Ascospore after 24 h, with very long capilliconidiophores (1-3) with capilliconidia at the tip (bar = 50 μm); c-1) Detail of fusoid capilliconidium (bar = 10 μm); d) Close up of perithecia showing asci arrangement and the semi-erumpent ostiole (bar = 50 μm); e) Ascus showing the spiral arrangement of ascospores (bar = 20 μm); e-1) Ascus cap detail (bar = 5 μm); f) Section of upper part of stroma showing asexual morph (Hirsutellalike A type), with long-necked phialides (bar = 10 μm); g) Phialides formed as mycelial cushions (sporodochia) on leg joints and antenna (Hirsutella-like C type) (bar = 10 μm). Images: João Araújo.