SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd382b35e8d8d12f3421dfdf97d3b75720aaa0ead373921024b70fa335ba331ac' 
  AND token = 'uulWshAupHYMP4V/4puFqij61yR6bKQ8p4cOwj3Ytzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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