SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2ad0a870d46a121aa823c41fa303fe4ab907a280a199a0903fbcb780f2720809' 
  AND token = 'frnJeOhBmXPzi6cDarn/nnvkGnyewEePlfiYcPnIc14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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