SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed21dee536431a7de9140477f7ea6224d4e810b13406ea9747dd3d8b5213ce1d' 
  AND token = 'LzbcNFoswtBWFtFHS7G5Psyr/9sY9Wkd8XcJ0iDKez4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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