Psyllipsocus clunjunctus Lienhard, 2013

Lienhard, Charles & Ferreira, Rodrigo L., 2013, Three new species of Psyllipsocus (Psocodea: ‘ Psocoptera’: Psyllipsocidae) from Brazilian caves with description of a novel structure interpreted as a male accessory genital organ, Revue suisse de Zoologie 120 (3), pp. 421-443 : 424-429

Psyllipsocus clunjunctus Lienhard n. spec. Figs 1A, 2, 3, 7G

HOLOTYPE: ISLA; 3 (slide-mounted); BRAZIL (GO), Damianópolis , cave Lapa do Ribeirão dos Porcos, 27.vi.2002, leg. R. L. Ferreira.

PARATYPES: ISLA and MHNG, slide-mounted and/or in alcohol ; BRAZIL, leg. R. L. Ferreira (unless other collector mentioned), from the following municipalities. 23, 1♀, São Desidério (BA), cave Gruta do Catitu, 24.vii.2006. 13, São Desidério (BA), cave Gruta do Sumidouro do João Baio, 29.vii.2006. – 1♀, Várzea Nova (BA), cave Gruta Jurema , 20.vii.2008. – 33, 2♀, 1 nymph, Damianópolis (GO), cave Lapa do Ribeirão dos Porcos, 29.vii.2001. 3♀ (one of them allotype), 1 nymph, Damianópolis (GO), cave Lapa do Ribeirão dos Porcos, 27.vi.2002. – 13, 1♀, Presidente Olegário ( MG), cave Lapa Vereda da Palha , 13.x.2010. – 53, 4♀, 7 nymphs, Baraúna ( RN), cave Caverna Britador , 11.vi.2010, leg. D. M. Bento. 2♀, 5 nymphs, Baraúna ( RN), cave Caverna Cipós , 11.vi.2010, leg. D. M. Bento. 33, 1♀, 3 nymphs, Baraúna ( RN), cave Caverna Escada , 27.i.2010, leg. D. M. Bento. 1♀, 1 nymph, Baraúna ( RN), cave Caverna Esquecida , 17.vi.2010, leg. D. M. Bento. – 1♀, Felipe Guerra ( RN), cave Lapa do Engano , 5.viii.2010, leg. D. M. Bento. 23, Felipe Guerra ( RN), cave Caverna Rumana , 19.i.2010. 13, Felipe Guerra ( RN), cave Caverna Rumana , 5.viii.2010, leg. D. M. Bento. 13, 1♀, Felipe Guerra ( RN), cave Gruta da Catedral , 14.ix.2008. 1♀, Felipe Guerra ( RN), cave Gruta Carrapateira , 24.iv.2007. – 43, 3 nymphs, Governador Dix-Sept Rosado ( RN), cave Gruta do Lagedo Grande , 21.vii.2010, leg. D. M. Bento. – 3♀, Mossoró ( RN), cave Caverna Trinta , 10.vi.2010, leg. D. M. Bento. – 13, 2♀, Aurora do Tocantins (TO), cave Gruta das Rãs, 8.i.2009, leg. R. A. Zampaulo .

DESCRIPTION: See diagnosis of the species group, with the following complements. General colouration whitish to light or medium brown. Head often with a characteristic pattern of brown hypodermal pigment (Fig. 2D), compound eyes dark brown to black. Tibiae lacking transversal bands. Abdomen whitish or with some brown hypodermal pigment, terminalia brown.

Both sexes brachypterous (Fig. 1A), in female (Fig. 2B) forewings at most reaching abdominal apex, in male (Fig. 2A) often somewhat projecting over tip of abdomen. Forewing venation with irregularities due to brachyptery, especially in the region of pterostigma and vein Rs (Fig. 2AB), the latter usually simple. Hindwings strongly reduced, often almost veinless (Fig. 2B). Compound eyes larger in weakly brachypterous specimens (IO/D about 2.6) than in strongly brachypterous ones (IO/D up to 3.9). Three ocelli present even in strongly brachypterous individuals. Antenna very long (more than twice body length) but usually damaged in preserved material; maximal number of articles observed: 29 (in a distally damaged antenna).

FIG. 1

Map of Brazil showing states and municipalities where specimens of the Psyllipsocus clunjunctus species group were collected. (A) Psyllipsocus clunjunctus Lienhard n. spec., habitus of brachypterous individual on guano (body length about 1.5 mm). (B) Caatinga formation (semiarid) which exists in the areas near the caves in RN. (C) Collecting localities (municipalities) in RN. (D) Collecting localities (municipalities) in MG. (E) Cerrado formation (Brazilian Savanna) which exists in the areas near the caves in MG. – States: BA = Bahia, GO = Goiás, MG = Minas Gerais, RN = Rio Grande do Norte, TO = Tocantins.

Broad apical lobe of hypandrium (Fig. 2GH) with a distally rounded sclerotized median area, bearing 4-6 setae near its middle axis; pilosity of basal part of hypandrium as shown in Fig. 5A for P. serrifer ; arrangement of the four dorsal placoid sensilla as shown in Fig. 2GH. Shape of latero-distal phallosomal sclerotizations and FIG. 2

Psyllipsocus clunjunctus Lienhard n. spec. (A) Forewing of brachypterous male. (B) Forewing and hindwing of brachypterous female (same magnification as A). (C) Spermapore sclerite. (D) Head pattern of female from Baraúna (RN). (E) Spermatheca containing one spermatophore. (F) Hind corner of clunium (arrow) and left ovipositor valvulae. (G) Hypandrium and phallosome, ventral view (phallosome observed through ventral wall of hypandrium, pilosity of basal part of the latter not shown), male from São Desidério (BA). (H) Ditto, male from Damianópolis (GO). of oval medio-distal phallosomal lobules somewhat variable, probably partly depending on position after slide-mounting; each lobule with two placoid sensilla (Fig. 2GH). Clunial bridge relatively simple, as shown in Fig. 3AB, central part seemingly articulated to the lateral parts by a partly membranous zone near the most narrow parts of the bridge (Fig. 3B). Central cavity laterally delimited by a rounded papillate bor- der; these borders representing the ventralmost parts of the bridge. Clunial bridge on each side with a dorso-medially directed spur-like posterior prominence.

Spermapore sclerite of slightly variable shape and length (Figs 2C, 3C). Spermathecal blade slender, file-like, weakly sclerotized (Figs 2E, 7G). Spermathecal duct more than twice as long as spermathecal blade (Fig. 2E), occasionally with a weak thickening near spermathecal sac. Spermatophore long and slender, about 7-8 times longer than wide, sausage-shaped (Fig. 2E; in the spermatheca of one female three such spermatophores could be observed; this indicates that the species is polyandrous; see General Discussion, below).

MEASUREMENTS: Both sexes relatively small, body length usually 1.3-1.6 mm, exceptionally up to 1.8 mm in male and 2.0 mm in female. Male holotype (brachypterous): BL = 1.5 mm; FW = 1114 µm; HW = 170 µm; F = 386 µm; T = 596 µm; t1= 320 µm; t2 = 52 µm; t3 = 66 µm; IO/ D = 2.8. – Female allotype (brachypterous): BL = 1.3 mm; FW = 733 µm; HW = 166 µm; F = 397 µm; T = 607 µm; t1 = 331 µm; t2 = 50 µm; t3 = 65 µm; IO/D = 3.0.

ETYMOLOGY: The specific epithet refers to the clunial bridge joining the hind corners of the clunium to each other (Latin: junctus, -a, -um; joined).

DISTRIBUTION AND HABITAT: At present P. clunjunctus is known from 16 Brazilian caves situated in 9 municipalities (see Fig. 1). These caves are located in three limestone formations representing different ages and structures. The Bambuí group ( upper Proterozoic ), located in Minas Gerais, Goiás, Tocantins and Bahia states, comprises the biggest limestone group in Brazil, and contains a considerable proportion of the known caves in the country. The Una group (also upper Proterozoic) occurs in central Bahia state, and is spatially contiguous to the eastern “branch” of the Bambuí group; it is therefore plausible to assume subterranean continuities between these formations. The Apodi group, located in Rio Grande do Norte state, comprises younger limestones, dating from the Cretaceous. This formation is isolated from the previously cited groups .

The geographic distribution of P. clunjunctus is somewhat surprising, especially when considering its brachypterous condition, which limits dispersion. The contiguity between the Bambuí and Una limestone formations would explain most of the present distribution, except for the “unexpected” findings in Rio Grande do Norte state. However, many potential habitats between northern Bahia and Rio Grande do Norte (as granitic outcrops, full of fissures and spaces) have not been sampled, and the “distribution gap” observed is probably a sampling artefact.

The physical attributes of the caves inhabited by the different populations of P. clunjunctus are very heterogeneous and cave morphology or size are apparently not relevant factors determining the presence of these insects. On the other hand, the presence of guano, especially old piles from haematophagous bats, seems to be

FIG. 3

Psyllipsocus clunjunctus Lienhard n. spec. (A) Schematic representation of slightly squashed male abdominal apex, with detail of clunial bridge, posterior view (1, epiproct; 2, paraproct; 3, clunium; 4 clunial bridge). (B) Clunial bridge, ventral view, posterior part upwards directed in the figure. (C) Spermapore sclerite of female (same magnification as B).

necessary for the occurrence of this species inside a cave. According to Ferreira & Martins (1999) and Ferreira et al. (2007) Psyllipsocidae generally prefer old guano piles in Brazilian caves and can be very abundant on this substrate.

DISCUSSION: This relatively small brachypterous species can easily be distinguished from both other species by the presence of a rounded sclerotized area on the distal lobe of the hypandrium, bearing some hairs in the middle, and by the characteristic arrangement of the four dorsal placoid sensilla of the hypandrium. The female is characterized by its particularly long spermathecal duct and the very large sausageshaped spermatophore. The simple clunial bridge and the file-like spermathecal blade are similar to the corresponding structures in P. similis . See also General Discussion, below.