SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ac1edc5e96fffaf80f6c2302c24d16aa2843f524ee7bba153f2b8437bb0d8853' 
  AND token = 'prMeVrUKmp4aKy1XSFdzsEBw46xE8L9sMJxY31vPBFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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