SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2d9ddb1be217d54699203621f451c95a7f39eb197573ce20f4212b860ff9b6c' 
  AND token = 'Yq3MlGlxEjb/pgLlFhsziKqkz/HwUacYxtt++aX5zyM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}