SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cd073a382010cb897c60dd48664c0b839404996bc1df93262e17b82782235f6b' 
  AND token = 'r+KST8iVdTMXwDORnEkbEAPfZDzMv1gLMaQJVAvSKp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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