SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b55d0ea7f724bc37a22093527d7edcbd9aa60aaf6076941363d4c38711387b3' 
  AND token = 'm8WSNsx6pFAj1Z9FAo/7q/gNPq6gW1uDnN0CzX/62tM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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