SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3c2e1ee3b10105796f5304c399427db2e97b245e16bc42b335a0cb3a32e8256' 
  AND token = 'nQ7jlSURK77bCJJgRYKhjAhcElAYWJlrCIxK0qP4SQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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