SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16576e9a069736de32b36fc15a0f50f263ff39d85ed4e2a17ded2d47ad4ff864' 
  AND token = 'lGvAF6pFDZt4LeU0rB+aKdKFPtHk93oOYRK4L+P772M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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