SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aa4ca8f3fe834a99105de606aab578ebc8dd42fda8c4fa3fd5d055dae55d6454' 
  AND token = 'f9zkF1ZANUFK/Sm8bVx304PIFFXKPfKy9u9ia78E/s0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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