SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '833465c0c1fcb5b46997b6bddc2c7c391d4fa544fcd59daccb7bc7c88ca5343c' 
  AND token = 'iYNYwCiUY44pKIMtYqQPA3gCXrBgZomD6s7eb4OSBTs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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