SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45c648641c49b1e3a8cfb17e93f265f736702ce86ef53acfddab6fa9e87bdad8' 
  AND token = 'wJnYwzzK32V+5umEielzbGvQR1u2zZQAakwg8UK/zWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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