SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0dc774458fe8267cd1b09e037ce482043a22b3e608339be0848a57f7c9baf827' 
  AND token = '8kBLTtSYXoZ629fuS4EwwbdoeeeYjTR+Skc9n7tTG8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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