SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b98d554e1b956b047a8b9d5869fbcde65eb7de9b492d33aa5d6a10be30591eba' 
  AND token = 'fdxRsgzFfyTLya192dE41GqNlWZkff/NICOSEfc4T7Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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