SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbd95358955b7bb941b02f8f514f29c9cef992ca4a7e1201301f312aee2f8746' 
  AND token = 'Qfnj0eLNKEE5eUOw/QbPNWnMYyGkpwcojCD6oYwmOCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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