It is Richard Dudley who tops this pedigree that Dean Dudley quotes as 'Richard Dudley of Clopton, who held land at Swepstone' whether this is true or not I don't know.
The pedigree Thomas gives, states to refer to Leicester and Northampton, which I assume means the visitation pedigree of Northamptonshire 1564 or 1619 of the Dudley family of Clopton Manor.
The 1564 pedigree is topped by -
Richard Dudley, Esq of Barnwell who marries Agnes or Joan Hotoft daughter of Sir Robert Hotoft of Clopton and had 3 sons, William, Thomas and John Dudley.
Succeeded by -
William Dudley, Esq of Clopton who married Christian Darrell daughter of UNK Darrell, Esq of Lillington Darrell and had 2 sons, Lawrence and Robert Dudley.
Succeeded by -
Lawrence Dudley, Esq of Clopton who married Frances Lesham daughter of Thomas Lesham, Esq of Lexham Burnham and had William, his only son and heir.
Succeeded by -
William Dudley, Esq of Clopton who married Elizabeth Porter daughter of Augustine Porter, Gent of Belton and had Thomas, Gilbert and William Dudley.
Suceeded by -
Thomas Dudley Esq of Clopton who married Mary Watsone daughter of Edward Watsone, Gent of Liddington and had Edward, Jeremy, John and Kenelm Dudley.
I'm not sure from whom, Richard Dudley of Swepstone descends. Thomas's Grandfather would be born c1530 and I think he is the Richard who dies 1605 listed as by will
'Richard Dudley the Elder of Swepstone, Yeoman'
Given the time period, Richard could be a grandson of William Dudley Esq and Darrell but im not sure.
The pedigree misses out a generation. Between Richard of Barnwell and William of Clopton, numerous sites and stirnet put this generation in -
Sir Richard Dudley of Clopton who married Elizabeth de Beauchamp daughter of Sir William de Beauchamp.