SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6b460a60b3446186efd4256111d4fb42d98face6be51f849431330ce38b2e2d' 
  AND token = 'ykAO1o+Jf7e6aGLw+n3Bd4/u35JlxjzL/YlUSLfUGeE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}