SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '013f1f8565c3972b77f683d521fe5cdbc8aa0ed209e422b7ada27e7ec537dc47' 
  AND token = 'msnzDM/WPe6qGAkPWg++ynKzwjeZDxRl1HfpU8RMDJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

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