SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '647342bf1dc5866d0a7abc2d80ad81ab40b715db68cfa8bfbf47610ef5c053ea' 
  AND token = 'ibFeGu28YxRPnPzGSBU9In7VVzucbVvrha0cBvjLqr0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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