Mendoza Belmontes Fatima, Melchor Ricardo N, Piacentini Luis N
UNLPam, FONCyT doctoral scholar, Santa Rosa, La Pampa, Argentina.
INCITAP- UNLPam, CONICET, Santa Rosa, La Pampa, Argentina.
PeerJ. 2018 Jun 29;6:e5054. doi: 10.7717/peerj.5054. eCollection 2018.
sp. (Lycosidae) burrows found in an open sparsely vegetated area on the edge of the Gran Salitral saline lake, in central Argentina, are described. Burrows were studied by capturing the occupant and casting them with dental plaster. The hosting sediments and vegetation were also characterized. Inhabited sp. burrows display distinctive features as open, cylindrical, nearly vertical, silk lined shafts about 120 mm long, subcircular entrances, a gradual downward widening, and a particularly distinctive surface ornamentation in the form of sets of two linear parallel marks at a high angle to the burrow axis. Instead, casts of vacated sp burrows showed some disturbances caused either by the reoccupation by another organism or by predation of the dweller. Two morphologies are related to reoccupation of burrows: those with a structure in form of an "umbrella" and another with smaller excavations at the bottom of the burrow. Predation by small mammals produces funnel-shaped burrows. Both active and abandoned sp. burrow casts are compared with existing ichnogenera and inorganic sedimentary structures, highlighting its distinction. It is argued that key features like the presence of a neck, a downward widening and the described surface texture will allow recognition of wolf spider burrows in the fossil record. However, the putative spider burrows described in the literature either lack the necessary preservational quality or do not show ornamentation similar to the modern wolf spider burrows. Fossil wolf spiders are recorded since the Paleogene (possibly Late Cretaceous), therefore Cenozoic continental rocks can contain wolf spider burrows awaiting recognition. In addition, the particular distribution of sp. in saline lakes may imply that this type of burrow is linked to saline environments.
本文描述了在阿根廷中部大萨利特拉尔盐湖边缘一片开阔、植被稀疏地区发现的狼蛛科（Lycosidae）洞穴。通过捕获洞穴居住者并用牙科石膏对其进行铸型来研究这些洞穴。同时，还对洞穴所在的沉积物和植被进行了特征描述。有居住者的狼蛛洞穴具有独特特征，如开口呈圆柱形、近乎垂直、有丝衬里的竖井，长度约120毫米，入口呈近圆形，向下逐渐变宽，并且有特别独特的表面装饰，表现为两组与洞穴轴线成大角度的线性平行痕迹。相反，空置狼蛛洞穴的铸型显示出一些干扰，这些干扰要么是由另一种生物重新占据造成的，要么是由居住者被捕食造成的。两种形态与洞穴的重新占据有关：一种是呈“伞”形结构的，另一种是在洞穴底部有较小挖掘的。小型哺乳动物的捕食会产生漏斗形洞穴。将活跃和废弃的狼蛛洞穴铸型与现有的遗迹属和无机沉积结构进行了比较，突出了它们的区别。有人认为，像有颈部、向下变宽以及所描述的表面纹理等关键特征将有助于在化石记录中识别狼蛛洞穴。然而，文献中描述的假定蜘蛛洞穴要么缺乏必要的保存质量，要么没有显示出与现代狼蛛洞穴相似的装饰。自古近纪（可能是晚白垩世）以来就有化石狼蛛的记录，因此新生代大陆岩石中可能含有等待识别的狼蛛洞穴。此外狼蛛在盐湖中的特殊分布可能意味着这种类型的洞穴与盐环境有关。
