SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd08126e4f9a301420a9a5f1fb0bab3560ecacd52f62f9bf4d46bf4d901cff691' 
  AND token = 'KrDDQAGl/ZwuYpg8EKaweV/Pqfh4Jp88Neco/Z+ssJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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