SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a5cb9d0c7da8aaa5e51bc53591e7287798ac7dee3600d8d814db039da8d76ec' 
  AND token = 'Nyk4vba3WjqWz8+OsHFdps+3Ugfc+TMmVswjMO05Y50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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