SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd1c8fc77e110143e52f2101100003695c3dcbfb5cccfc820faa0345db009813' 
  AND token = 'fuQYSVRtY+1tPCbHRVF3x0P2ohgSmu9vBjzsp4cnIF4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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