SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '61100e56b04d4e4654ae434344ab8e0052ceaf30db7ff1d5790c2eb1bf9e3440' 
  AND token = 'Y/1qfHOPxr0PJMH0GdG3FzmjXGPYZOYpUHr03jXaF8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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