DOI: 10.5061/dryad.8sf7m0cwd
title: Measurements of Silurian brachiopod specimens from the Pentland Hills, Scotland

description: 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.
description: These are measurements made on fossil brachiopod internal and
 external moulds.
description: # Measurements of Silurian brachiopod specimens from the Pentland Hills,
 Scotland ## Description of
 the data and file structure The data are loosely structured in an Excel
 spreadsheet and and be cut and pasted if necessary. **Brachiopod
 measurements** Taxa, and the raw measurements taken from them, are listed
 here in alphabetical order. The number of ventral and dorsal valves
 measured is included. The measurement variates used (X1, X2, etc) are
 explained below. Specimen numbers are colour coded according to the
 formation in which they were located: red – Wether Law Linn Formation,
 purple – Cock Rig Formation, green – Deerhope Formation, blue – Reservoir
 Formation. Measurements variates used in the present study, modified from
 Harper (1989). All measurements are in millimetres. Missing cells record
 missing data, due to incomplete specimens. X1        sagittal length
 X2        maximum width X3        position of maximum width measured from
 posterior margin X4        maximum depth measured perpendicular to
 sagittal length X5        hinge width X6        maximum length X7       
 origin of fold or sulcus measured from posterior margin X8        maximum
 width of rim or limbus X9        maximum length of muscle scar measured
 from posterior sagittal margin X10      maximum width of muscle scar 
 X11      wavelength of median rib at 2mm (or 5mm*) growth stage X12     
 position of apex measured anteriorly from posterior margin X13      length
 of base of spondylium X14      maximum width of spondylium X15      length
 of base of cruralium X16      maximum width of cruralium X17      anterior
 extension of brachiophore bases measured from umbo in plane of sagittal
 length X18      transverse separation of ends of brachiophore bases
 (dorsal valve) or teeth (ventral valve) X19      maximum depth of sulcus
 X20      maximum width of sulcus/fold X21      length of cardinal process
 base X22      sagittal length of submedian septa X23      transverse
 separation of anterior ends of submedian septa X24      sagittal length of
 median septa X25      angle of geniculation X26      maximum width of
 visceral disc X27      sagittal length of visceral disc X28      number of
 rugae or growth lines X29      maximum width of hingeline occupied by
 denticles X30      sagittal length of bema measured from posterior margin
 X31      maximum width of bema X32      angle of divergence between lobes
 X33      delthyrial angle  X34      angle of divergence of muscle scars
 X35      number of denticles X36      maximum length of spines X37     
 number of capillae at anterior margin X38      sagittal length of pedicle
 track X39      maximum width of pedicle track X40      sagittal length of
 midline X41      number of ribs X42      number of growth lamellae within
 1mm of anterior margin   *Variate calculated using 2mm growth stage except
 for the following taxa where the 5mm growth stage was used: *Erinostrophia
 undata* (M’Coy, 1846), *Eospirifer *cf. *radiatus* (J. de C. Sowerby,
 1834), *Meristina*?*maclareni* (Haswell, 1865), *Pentlandella pentlandica*
 (Haswell, 1865). HARPER, D. A. T. 1989. Brachiopods from the Upper
 Ardmillan Succession (Ordovician) of the Girvan District, Scotland, Part
 2. *Monographs of the* *Palaeontographical Society*, 79-128, pls. 12-22.
 [doi.org/10.1080/25761900.2022.12131804 ](https://doi.org/10.1080/25761900.2022.12131804) ## Sharing/Access information The data are original measurements made on fossil specimens.