SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5383048907e3132e681663df452833b00982277fe8990b31d4eaf7fa6f7789dc' 
  AND token = 'hHeA2EdvcutzOaLwUAochMSeuqnqvohkKAL+YNAEhb4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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