SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '735efd5e9f599a76a9f5bcd971518784b05531b6066f9cab40c972c3fc9f11c1' 
  AND token = 'mzV1ThcwNI+2HSG86wxe3/ZmYuGLBmCwvJe9ih8bdE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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