Measurements of Silurian brachiopod specimens from the Pentland Hills, Scotland

The abundant and diverse brachiopod fauna from the Silurian (upper Llandovery-lower Wenlock) rocks of the Pentland Hills is described within its geographical stratigraphical context. The majority of species are described in detail, discussed and illustrated. A total of 53 species attributable to the following superfamilies are present (numbers of species, including those in open nomenclature, in parentheses):  Linguloidea (7), Craniopsoidea (1), Discinoidea (4), Strophomenoidea (9), Plectambonitoidea (2), Chonetoidea (1), Childiopsoidea (2), Skenidioidea (1), Dalmanelloidea (3), Pentameroidea (2), Rhynchonelloidea (4), Atrypoidea (4), Athyridoidea (5), Cyrtioidea (5) and Delthyridoidea (3). Five new species,  Leptaena eska, Isorthis (Ovalella) clarksoni, Dicoelosia paratenua, Oglupes scotia and Lissatrypa scotica, are erected. Nevertheless in terms of abundance the fauna is dominated by individuals belonging to the Strophomenoidea, Plectambonitoidea and Dalmanelloidea. The composition of the fauna, its deeper-water setting associated with finer-grained siliciclastic substrates characterizes this Pentlandian biota.

Methods
These are measurements made on fossil brachiopod internal and external moulds.

本研究基于彭特兰丘陵志留系（兰多维列统上部-温洛克统下部）地层产出的丰富多样的腕足动物（brachiopod）群，在其地理与地层学背景下对其展开系统描述。绝大多数物种均得到详细描述、讨论并配有插图。本次研究共记录了隶属于以下超科的53个物种（括号内为物种数量，含采用开放命名法（open nomenclature）的物种）：舌形贝超科（Linguloidea，7种）、颅形贝超科（Craniopsoidea，1种）、圆盘贝超科（Discinoidea，4种）、扭月贝超科（Strophomenoidea，9种）、褶脊贝超科（Plectambonitoidea，2种）、长身贝超科（Chonetoidea，1种）、奇迪贝超科（Childiopsoidea，2种）、斯肯贝超科（Skenidioidea，1种）、达尔曼贝超科（Dalmanelloidea，3种）、五房贝超科（Pentameroidea，2种）、细颚贝超科（Rhynchonelloidea，4种）、无洞贝超科（Atrypoidea，4种）、阿蒂尔贝超科（Athyridoidea，5种）、曲壳贝超科（Cyrtioidea，5种）及德尔泰贝超科（Delthyridoidea，3种）。本次研究建立了5个新种：埃斯卡薄壳贝（Leptaena eska）、克拉克逊等脊贝（卵形贝亚属，Isorthis (Ovalella) clarksoni）、纤细双腔贝（Dicoelosia paratenua）、苏格兰奥格卢普贝（Oglupes scotica）及苏格兰丽无洞贝（Lissatrypa scotica）。就个体丰度而言，该腕足动物群以扭月贝超科、褶脊贝超科及达尔曼贝超科的物种占绝对优势。该动物群的组成及其产出的深水细粒硅质碎屑沉积背景，共同塑造了彭特兰生物群的典型特征。

研究方法
本次研究的测量对象为腕足动物化石的内模与外模。