SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25d5a8400acb2081f61af77277cddfc374d662121d5afc4ffc6a7557be0f3be0' 
  AND token = 'jNUWYQkuV1mt89EWUrgve6ggy/szX1LZMFLqemOk45g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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