SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0568fb44d9352ea0bcccb2d9757cc8000b544a2555bea5600012a780ab6588b' 
  AND token = 'l/qS+INshGBkxVM2it4bdUh5R+Q+UJ5Y8HTAa+Rn/UU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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