SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d41447d0c5b7ccc6dcdc3eef1b03b96b6d5da7d6a0c92928e5d34658ffb3abe' 
  AND token = 'gUVwl+0jw7YW8n612mA9ylrw+OzOTSdnK/DUtYHmvZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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