SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16f00698527a53388a8d69b94c1c7341cbc93b03eef8024b57eb145ff5d99274' 
  AND token = 'fvlKVCG6x95SckthSrKoA/z7mgQmTjUJXE9/4qLRbq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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