SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68bf6ec45f22159bd001707477562ea35bb33fb63eb58486ffd4c76fcb0093de' 
  AND token = 'GTORfm8YyvVKW1H/nU/PM6vwY9R44FQFOnMzF9VWKBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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