How to extract prosite patterns for Ciona intestinalis using Biomart

Question

By using Biomart I have been able to extract prosite patterns for a list of genes for a few species.

e.g. for humans, to extract the prosite patterns start for the foxa3 gene, I would use the code:

library(biomaRt)
ensembl[["hsapiens"]] <- useMart("ensembl", "hsapiens_gene_ensembl")

ensembl <- list()

prosite_foxa3_hsapiens <- getBM(attributes = c("ensembl_gene_id", 
                                      "scanprosite_start", 
                                      "ensembl_transcript_id", 
                                      "transcript_biotype"),
                       filters = "external_gene_name",
                       values = "foxa3" , 
                       mart = ensembl[["hsapiens"]])

I wanted to be able to simply change the mart to the appropriate mart for Ciona intestinalis and use the same attributes e.g.

library(biomaRt)

ensembl[["cintestinalis"]] <- useMart("ensembl", "cintestinalis_gene_ensembl")


prosite_foxa-a_cintestinalis <- getBM(attributes = c("ensembl_gene_id", 
                                      "scanprosite_start", 
                                      "ensembl_transcript_id", 
                                      "transcript_biotype"),
                       filters = "external_gene_name",
                       values = "foxa-a" , 
                       mart = ensembl[["cintestinalis"]])

Unfortunately, there isn't a ''prosite pattern start'' attribute when using listAttributes(ensembl[["cintestinalis"]]) for Ciona intestinalis even though these are available on the Ensembl website.

I wondered if there is maybe a workaround for this?