SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebaa6e1fdf1f4ff0fbaee194c0678c89f291669f427cc0081e21365ac198218d' 
  AND token = 'xFDWZOQF7Ae94XBZJpZL+BwtFjldgwEw+O+ZneYIepI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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