SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bb2a44db93cfe62e3fb9c3883eec65dcff57176b03fc9b7bcceee57d61d00c9' 
  AND token = 'fxL5UYQdHSPVSSoA8qWqILQodX8wXYgx0o2m9Hm9xS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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