SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f02d3c39c9bde814f41186822ac28a57e52acf48f2874c9bfe59e029196f5717' 
  AND token = 'MMD9CZObwFrcYThvqsgaL8gjCFb5JIZkD2DP47kz+LU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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