SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7d5cdff99fe83f247fad0e153d0d22d50a19f43c1ac895d22c499a38b7beb9bb' 
  AND token = 'WUy1Iu0ps+AvVDNk30QBtcBydzSqZPoW2jKr27o0cYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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