SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '834c425c6225ce11dae23ea7ea74fe8041539f9b2f644c8c693229475787e75b' 
  AND token = 'JDHz3Y++K71nM2unnSszcwn+Rq7E4LNxHpYGXxYDEaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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