SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c6a24b2c745c817e9a36930a496c277300ae6556d81020220da6e4cbd58ef624' 
  AND token = '8hwph1aTYuzIgTdT8st+mQ+NY1BgK8RdzJj37sNvNCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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