SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf6c184bab26b4d39c2eae2af6c4879260b2f5fd59fb4cd1e34e126a6c1b5374' 
  AND token = 'rI1AJg0jnYH99yQSLtUnHV1sLEg5et250a8Ft/117I4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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