SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f37c7b574b47ec5e259a05a316c9ccc034336a267ae701844e9aefa5e445331b' 
  AND token = 'Z1Ml7GAUcExEG1J4VRjcbp3EkwLHosaoth+HcuViPWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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