Pherotilla Brothers, 2015

Brothers, Denis J., 2015, Revision of the Rhopalomutillinae (Hymenoptera, Mutillidae): 1, generic review with descriptions of three new genera, Journal of Hymenoptera Research 46, pp. 1-24 : 7-11

Pherotilla Brothers gen. n.

Figs 1 , 11-18 , 33-34 , 41-42

Type species.

Rhopalomutilla mlanjeana Bischoff, 1920: 180, male & female (name determined under Article 61.4 of the Code ( ICZN 1999))

Diagnosis.

MALE. Head transverse with vertex evenly rounded in anterior view; no genal carina; mandible tridentate; scutellum pulvinate, evenly swollen; S6 with posterior margin deeply notched laterally; S8 strongly sculptured with prominent peg-like process laterally and posterior margin broadly and unevenly emarginate; penis valves asymmetrical with right valve larger than left (sometimes symmetrical), each elongate without any setae along posterodorsal margin, outer surface smoothly convex; paramere without cluster of very strong setae arising under a flange dorsobasally but often with a few slightly stronger long setae near base. FEMALE. Head rounded in anterodorsal view, about as wide as long; mesosoma squat, lateral margin with several teeth or tubercles, strongly convex anteriorly, with gradual concave narrowing between metathoracic spiracle and propodeal spiracle, lateral margins of propodeum diverging posteriorly; disc of propodeum posteriorly indistinct, without any median tubercle and with strong tooth at lateral angle; metasoma slightly elongate with T1 broad; pygidial plate oval, bounded by carina ventrolaterally, surface covered by dense recumbent setae, posterior margin convex between weak apical teeth.

Description.

MALE. Body black (seldom with tegula and/or legs brown); wings hyaline basally (sometimes almost entirely infuscated). Head: transverse with vertex more or less evenly rounded without any elevation behind ocelli, posterodorsal margin of head in anterior view more or less evenly curved; antennal scrobe above with transverse carina separated from secretory tubercle; clypeus with ventral marginal teeth; genal carina completely absent, postgena slightly convex; postmandibular carina weak and short or moderate and long (rarely absent), pleurostomal carina absent (sometimes a ridge from posterior mandibular articulation to margin of proboscidal fossa slightly posterior to half its length); mandible tridentate with middle apical tooth smaller than other two, ventral basal lamella gradually narrowed apicad. Mesosoma: mesoscutum anteroadmedian lines separated by a longitudinal ridge; notaulus incomplete anteriorly; parapsidal line very short and incomplete posteriorly; tegula evenly convex or slightly recurved posteriorly; scutellum pulvinate, evenly swollen without any posterior tubercle; metanotal dorsellum variable in form and sculpture; propodeum with disc and declivity very weakly differentiated, evenly merging; lateral face of pronotum fairly strongly tapered, anteroventral margin a weak ridge continuous with undeveloped anteroventral tooth (sometimes tooth moderately developed); mesepisternum with transverse depression moderately developed to imperceptible; mesosternum with a short crenulate transverse carina on each side about halfway between anterior margin and mid coxa or without any distinct projections. Legs: pubescence denser on tibiae and tarsi; claws deeply cleft apical to broad lamellate base; fore tibia without any apical secretory structure (sometimes with a vertically elongate preapical groove/pore on inner (anterior) surface); mid and hind tibiae with preapical dorsal and lateral spines few and difficult to distinguish. Metasoma: fairly slender; T2 widest beyond midlength; T2 and S2 without any traces or with dispersed traces of lateral felt lines; pygidium (T7) with apical margin convex, edges not recurved (sometimes slightly so, rarely flangelike); S1 without any tooth; S6 with posterior margin deeply notched on each side; hypopygium (S8) strongly sculptured with prominent peg-like process laterally and posterior margin broadly and unevenly emarginate. Genitalia: basal ring moderate; paramere curved with narrow apex, without any differentiated very strong setae except some times with a few long thicker setae along basodorsal margin; penis valves asymmetrical (sometimes symmetrical) with right valve slightly larger than left, without any setae.

FEMALE. Head: rounded in anterodorsal view; sides produced far behind eye, poorly to fairly well differentiated from posterodorsal margin of head; posterodorsal margin convex, without any distinct depression at each side; clypeus with a median tooth above small triangular area, a broad smooth ventral concavity, an acute lamellate tooth at each side of concavity; gena broad, without or with a weak posterior ridge; postmandibular carina irregular running from mandibular base to level posterior to posterior margin of oral fossa then obsolete; pleurostomal carina forming a ridge from posterior mandibular articulation to margin of oral fossa; mandible evenly curved, with inner margin expanded into an obtuse triangular lamella about one-third length from base, apically weakly bidentate; maxillary palp two- or unsegmented, weakly fusiform; labial palp two- or unsegmented, slightly broadened apically; antennal scape with a lamellate rounded tooth posterolaterally, flat anteromesal surface delimited dorsally by a weak carina basally or not at all; pedicel sometimes with ventral tuft of fine setae. Mesosoma: squat, no longer than wide or only slightly so; anterodorsal margin indistinct with fairly short anterior face at an obtuse angle to dorsal face and merging with it; humeral angle dentate or tuberculate; lateral margin uneven and tuberculate, anteriorly strongly convex, gradually converging to notch at base of propodeum then diverging to posterolateral angle with strong tooth; disc of propodeum posteriorly poorly discernible, fairly smooth and without any median tubercle; posterior face of propodeum strongly oblique; lateral face of pronotum flattened with no (or a weak) anterior oblique carina, a curved low ridge running along anteroventral margin, ventral margin fairly straight, anteroventral extremity obtuse; mesepisternum strongly convex, with or without a vertical ridge above or anterodorsal to mid coxa. Legs: fore leg with femur flattened below, tibia with preapical elongate to oval secretory pore on inner (anterior) surface, tibial calcar with blade smooth on margin; mid and hind femora flat to weakly longitudinally concave below, each with a basally broad preapical lamella anteroventrally; mid and hind tibiae with preapical dorsal spines very strong and easy to distinguish, preapical lateral spines strong and fairly easy to distinguish. Metasoma: fairly slender; T1 with anterior face meeting dorsal face at a rounded right angle, dorsal face long, very broad and transverse, almost as wide as T2, sides broadly convex anteriorly then convex and somewhat diverging posteriorly; T2 about as long as T3-T6, broad deep basal depression strongly convex posteriorly, sides beyond basal depression diverging then convex and converging, small indefinite felt-line patch anterolaterally (sometimes absent), posterior margin straight to weakly concave; T3 with posterior margin straight (sometimes very weakly concave medially); T5 without (seldom with) a tuft of fine setae at posterolateral angle; pygidium (T6) with pygidial plate oval, with a strong lateral bounding carina ventrally, sculpture concealed by dense setae, apical margin convex between two blunt teeth; S1 with a short median carina anterior to a broad flattened triangular area bounded by ridges and elevated anteriorly, narrow lateral marginal depression on each side posteriorly; S4 with posterolateral angle simple (seldom produced); S5 with posterolateral angle not (seldom scarcely) produced, without (sometimes with) a tuft of setae posterolaterally; S6 entirely slightly convex, apex acute, sides weakly angled to carinate, no flattened strong setae.

Species included.

Pherotilla japhia (Cameron, 1902), male, comb. n.; P. mlanjeana (Bischoff, 1920), male & female, comb. n.; P. oceanica (Mickel, 1935), male & female, comb. n.; P. rufitincta (Hammer, 1957), male & female, stat. n., comb. n.; P. striganovae (Lelej, 2012), male & female, comb. n.; five undescribed species, four male only, one male & female.

Distribution.

Southern to eastern Africa (Kenya, Malawi, Mozambique, Namibia, Tanzania), southern to southeastern Asia (India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Sri Lanka, Thailand, Vietnam).

Etymology.

From the Greek verb φέρω (phero), to carry (referring to their phoretic copulation), combined with - tilla, a common suffix derived from the genus Mutilla ; gender feminine.

Comments.

Both sexes have already been described for only one of the Afrotropical species ( P. mlanjeana ); although only a single female specimen is known to me, I have designated this as the type species since the male is more typical for the genus than the most commonly collected Afrotropical species ( P. rufitincta , for which several specimens of both sexes are known). This is the only genus of Rhopalomutillinae which is found outside the Afrotropical Region, occurring also in the Oriental Region, for which there is no evident explanation since we know nothing about their ecology. Although two species have been described from far south-east Asia ( Rh. oceanica Mickel, 1935 from Borneo and Rh. javana Pagden, 1949 from Java), these differ only in coloration and I have seen several specimens from neighbouring islands with intermediate colour patterns but essentially identical morphology (including the male genitalia), so have concluded that only one variably coloured species is involved, and Rh. javana syn. n. should be synonymized with Rh. oceanica ; a detailed justification will be provided in a subsequent paper.

Figures

Figures 1 - 2. Rhopalomutillinae, mating pairs, male above. 1 Pherotilla rufitincta (Hammer) 2 Bischoffiella cristata (Bingham). Scales = 1 mm.

Figures 11 - 18. Pherotilla gen. n. 11 - 14 P. mlanjeana (Bischoff) 11 - 12 male, dorsal & lateral views 13 - 14 female, lateral & dorsal views 15 - 18 P. oceanica (Mickel) 15 - 16 male, dorsal & lateral views 17 - 18 female, lateral & dorsal views. Scales = 1 mm.

Figures 31 - 38. Rhopalomutillinae, hypopygium (S 8): left = lateral view, anterior to left; centre = ventral view, anterior to left; right = posterior view. 31 - 32 Rimulotilla gen. n. 31 Ri. tongaana (Peringuey) 32 Ri. conifera (Bischoff) 33 - 34 Pherotilla gen. n. 33 P. mlanjeana (Bischoff) 34 P. oceanica (Mickel) 35 - 37 Rhopalomutilla Andre 35 Rh. clavicornis (Andre) 36 Rh. carinaticeps Bischoff 37 Rh. anguliceps Andre 38 Bischoffiella cristata (Bingham).

Figures 39 - 46. Rhopalomutillinae, male genitalia: upper = dorsal view; middle = left volsella, exterolateral view; bottom = sagittal view, penis valves and right paramere (right volsella not shown). 39 - 40 Rimulotilla gen. n. 39 Ri. tongaana (Peringuey) 40 Ri. conifera (Bischoff) 41 - 42 Pherotilla gen. n. 41 P. mlanjeana (Bischoff) 42 P. oceanica (Mickel) 43 - 45 Rhopalomutilla Andre 43 Rh. clavicornis (Andre) 44 Rh. carinaticeps Bischoff 45 Rh. anguliceps Andre 46 Bischoffiella cristata (Bingham).