SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c6a47ca837ab3a3b6dacb134f13bdcb9db8d12c12ebc94149bbce5280906c79c' 
  AND token = 'BSk+kDbHUIl3AAYXoANexnZ+ylLqwcC+kMjbS3S7IGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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