SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7ef97544c4887c153452a08b7ab15bd390d948aca119b20e1d3d6c0cfaed6c5' 
  AND token = 'CUG2zn1Deg+Iol+fXqu0sYV3MuDl9N05mvmgxgAwSqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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