SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae3fe073faa788c9652871a33cece954b4ef7f014c546e546c639fb65ce025da' 
  AND token = 'wgAK5KFmld3MtDariIpai55egN7iFXMxQdtHYuxVdio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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