SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb9755fcad21f4fc2daf484a2918a6723a224b6fd348108e8bf59023900b7593' 
  AND token = '8ISU3Vn28bExNnn6ToB7CxdcmDZ7CM+p6qK/y9UsDfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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