SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccee479aa0a926c14d373b5f3bcedfe11c0e3c767b8d222a4d0de7e2e88d6af9' 
  AND token = 'VZRytq2fb2vqdsrVltTwtRENvOE9vzgr/0fJXyaSPtU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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