SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bb370997f203a57e7e910deaa95561e286b0310f9aae71c9a235c7223fd7e38b' 
  AND token = 'jKCq1ZXSgLvVXivKmuymnjwXaob5jfAu9eaa1LPaqQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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