SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ef2297b1f1fc159de05007acf7236a38f4559db55b39eb4303d0c799494aab8' 
  AND token = 'ygn+Hn8K06BZW2ffmx19z03mUXM6356ImR1LWWDBx4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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