SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1f3c3e188fe9a12a065536d4586e5ed0f2ab4bb34b4f0194327b9aaf7e6495a' 
  AND token = 'zrYMwjQ7p5WkfVrvDqvZhO7wjE77UAqw9zbDEhLHrhk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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