SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '221dec1565d038fe9f2582b9baa604783a7df1e7ca104af53321db4cc16bc1b6' 
  AND token = 'Kvbx0AFqc8994xqnH8sVuZeGfqcLmVLEhM7ZNUK7UB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}