SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cae9d1777498e84671c626b5fd8ece8166758cddd9e5f8f6463fe5ba77b20e83' 
  AND token = 'NwSNo1+7qFQe8NCTrTLus5xa5GabgE4jy4ZE0M4nsbQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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