Ogulnius O. Pickard-Cambridge, 1882

Ogulnius O. Pickard-Cambridge, 1882: 432 .

Type species Ogulnius obtectus O. Pickard-Cambridge, 1882 .

Diagnosis

Males and females of Ogulnius can be distinguished from those of other theridiosomatid genera by the opisthosoma overhanging the prosoma (i.e., eclipsing the thoracic area) (absent in other genera), and the first tibiae with a retrolateral membranous patch (Figs 28B, 29B, 30B, 31B) (absent in other genera). Males of Ogulnius are also distinguished by a bifurcated mesal embolic apophysis (in contrast with non-divided or multiple times divided embolic apophysis in other genera), and its elongated prolateral branch (next to the embolus) that encircles the bulb counter-clockwise (Figs 28C–E, 30C–D; see also Coddington 1986 and Dupérré & Tapia 2017). Females of Ogulnius are also distinguished by having completely sclerotized copulatory ducts (in contrast with irregular and membranous or distally sclerotized copulatory ducts in other genera), with the copulatory openings exposed, protruding from beneath the transverse groove posteriorly (Figs 29D, 31D) (misinterpreted as “interrupted transverse groove” by Coddington 1986 and Dupérré & Tapia 2017; also compare “groove pockets” in Dupérré & Tapia 2017: figs 11–14, with Coddington 1986: figs 124–125) (absent in other genera).

Description

Females of Ogulnius have convoluted copulatory ducts that insert dorsolaterally posteriorly into spermathecae (Figs 5F–G, 29C–D, 31C–D; see also Coddington 1986 and Dupérré & Tapia 2017). For further genus description details, see Coddington (1986) and Labarque & Griswold (2014).

Remarks

Coddington (1986) suggested that a sternum truncated posteriorly was diagnostic for Ogulnius, but this character is also present in other theridiomatid genera (i.e., Chthonos, Theridiosoma, Epilineutes, Wendilgarda). We confirm the presence of a membranous patch on the retrolateral face of the first tibia in the two species of Ogulnius here examined (see also Ogulnius obtectus Keyserling, 1886; Coddington 1986: 57), seemingly a synapomorphy of the genus.