SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '084091ffc33ab154db73fe3a186b968cc807268c502bf99a5dbd468392cb35ee' 
  AND token = 'zr/pPC0VfvYN+HlpyMazSD/5Av+Ps/nBtAOINQzYyY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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