SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01e5bf6662768fbe0e379d89ee1148305331d6ab30dd83e9ccb5afd25515a391' 
  AND token = 'gN4bkYSFmnXo9biVKJOdfJlp+ch6RB/U1KDPxhduGog=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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