SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25b7c4b6c9ba0546ac16f834494083eac58ef5bfc5a4797614885d29bcdee76e' 
  AND token = 'MFrc/6wLBlKzyFw9KDKimnymh/jaiRKHmS+3cJvrzF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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