SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a6ce791fd99791d7c1fe03c7c84aa1ac9063b9b038daebe33871f5ef7fd853e' 
  AND token = 'WASPVfsq95tYVOpFCLtSMA3WBkdzzKrPLRKQ4CwRwrc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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