SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70c281a74334032589c0219789a132151ce3c00b9ee5b817968eb9e864967cfa' 
  AND token = 'RhaJsfYOYvhoMNNdvMNkRKFATgVrrmeZ64VeGH6eqjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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