SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '889bf961b6987382133a55525b0d81e06f1c56493053c9f6c72b7c2fba93c4e2' 
  AND token = 'ymaIvZEhE5sRH+AFy+LzKHRm7vNq9uSqc3lWZ+PYqTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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