SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0944d0be5c7ca12ffcbe27595880f797f8b17cb0fc22b3cda45b1b7c873a5dbb' 
  AND token = 'nWPPl2EaD86Qum8TP5HcslVKZqX0i4tSNrgbttuErwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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