SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17f1cc538dfe3d75a80659bf98cdb96177b3f0078b8e4394636234d6a8852e55' 
  AND token = 'uJG74La4Zbq7ZLYvQCSHghEkmkQ4rdhZ+gvAGQ/8gs0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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