SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fdd0ba26930d2b7afe0703a68bf220511e983138c89c2c91ab3b6043bdb20887' 
  AND token = 'UxnJrjN+0rpNtpv1dq4dvE3LBvPGpnfvuZsoFwCIPGo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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