SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d7ddec62a3695e85df0fecab9f13ea8f2bed8569fa2a1b471bd2e1feff73408' 
  AND token = '0hiuRlNU/I7DgM0JSk8/1ihUzCOTwijX1N42QfOdQ1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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