SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '488b6d3244d35253a5d0fbd078ba7ef9a03d04ae45bd0176313a53a4a30e9763' 
  AND token = 'QXU4p7jnVFQhqy4Hmz1Bm/cA4ju8jUcGC8DJWfejm0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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