SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '578d25e6f0f810ee9c250b574b89e0dab8f1daf3d6330d94d850e6d1dab8e1bf' 
  AND token = 'jQmL7aTbmgsYA0zwpC1B++OY+qXhF2tL4SFwjAZEiiE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00091

JSON explain

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