SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5056723466eb0bb2072a75f90e032b260e77fa95459e0dd9e77b1a7c93719ae9' 
  AND token = 'Xqy+9RCV/Q2AsBhJGOGA09a5YgVWsUZEB+o7LwPNvuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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