SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe2f36cb3946dcd1740ca369d76e7615ab930d90b1dceb7217427155d432563c' 
  AND token = 'SUymVfbbghtnshid8MPmgRIdBt8YNrbqFuuJix1h4lE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}