SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2ef7bd3aa04c86889ca076b5e253199502e65c5f11d8ea2f8bc960b360e91b9' 
  AND token = 'bfpPFsculg0CeeHhmXi6aLYjycvlSTyZ2TYMdGdooMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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