SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '740bfa5198712ee04f2b770f4f0022185cccc443a40f837393ad504f6eb4f4df' 
  AND token = 'Jhfpk5ZhYem+jwmPhCxytJKalpT3zr5sRXUNmevgflQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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