SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f43526db0615c76c0c56e65a8d59bdbe1ddf4d7d7adca48417b65fa58a208203' 
  AND token = 'nDI8zgrXtyx6HnSYLzI7D/zRmsfpWDDKT7ORfT9dV1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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