SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f829584be9915a4e7310e1fe96a27ad52a0272e9db2fa8f6f1098938cefdc33a' 
  AND token = 'LDppelrNRslu+pM4cP6WqsL2GAQQXsUJugbPYS6KQEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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