SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ca222c1c19867ae2d36a382b4861fd286a088d7ecccf646b95ad2ec3228626c' 
  AND token = 'gn+lduWmHYR6j5pcdxwoI/AuG0OvdHOguBDlG3FS+cI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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