SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc26f3f19e316d4645f2fe87bbe56c8afc13c226932d55d596eb928846d22a3a' 
  AND token = 'WD/RYkOSymUXgl+ku89Z5cT/zhhYwkTVRB7RYp/rtr4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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