SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c807af5364c63979d89f70beeaabb81a413dd4defbfa6abd3c61234497f2953' 
  AND token = '7sNsIbbgp3Oe8Ja+MyX7EqwQkOfVKzhSeiCoXWo24iU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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