SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68349b33c7ca4e3d648545632c058248c654036d9ebe1bf23a5615d9f60d013e' 
  AND token = 'oTWAW+yJ75tFbvONWiuIl81RevQooE5pOd9ZlnzVV9s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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