SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2fcf04706065efcc20051df86f372799c63ec9e02bbd29316cf9d1f890696325' 
  AND token = 'nmHZvdsKy3+mNWEQC148JKntm3Yt/S1Lxym1UZAU4u4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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