SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '27c59b50f7c3ba8970d0f409a0fb701c8f673e5919bc1ba3c87b224c8aaa93eb' 
  AND token = 'Um7uS7YvSusCHXjYMDovKohoslEWJ8oV7mqGqEzBtNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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