SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f58f8711fa781964a099eb550ffdb89ada052fdc3c9db9ff6506819524477351' 
  AND token = 'VKibIx8MQnLqj0y8bBVvGmU9C2cchpJ561JVm6mKBdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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