SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13f883b9066f3c97388e6749c8889c10b01df2f3f58ca2f3754213fdccffeb2f' 
  AND token = 'nnAjY6h5vt/YnQtVQNYgGcIaFFCUr2wcc+6ZodwvNoM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}