SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2549d6871c542f4b5e224c88e55941c26d227760436eae1d79f8c06e563ebc4' 
  AND token = 'PRAF7uRiI72za0ah9BCDrNeEcjsWsKTsvhbYs/PoNMc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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