SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6333c0d00124f062e2134941ff41439e85a640677e43e549c4b50a1469bf01f1' 
  AND token = 'nQWy3ytE09ByWsdavrilf6Lz7rzFgcLPrgzn3syrxZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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