SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c59e00c1471d726e0d3ae3ebdf91f698acb37bd87188bdc532f1b06c22bbe1' 
  AND token = '+4iY2QhEzfeyR/JplQercGMjCE4Iw/x3z/nnYSr7rfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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