SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b22e671f67d4b4b631ce238c0a4c08f971903acceaca054869e23cd4a35c4a5b' 
  AND token = 'k11cmSM3iTipHzwLDTHXuFgEg8CE8GQ5jsZLB7nwM/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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