Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6cfb8b8441ef4d7f2e38d23a37c313c535d6bb5246356b333d6a1d0642b032c' 
  AND token = 'MiVHwQU644uhCwx7uwGOuXfImJXj1siLrYWSQ0AmDcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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