SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b258bc799f59c6900003b093d60db9879a7efca606dccaf47df8f9246ae36d8' 
  AND token = 'iFEioy5jjqmHLKCG7JY5vQTVRaQUJ6ZeT9QfDLJNJoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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