SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4dbb76389b66c6903ffb86fe5c4f095fdcc17aa652b2cd8f7b82dcf10ddbe33f' 
  AND token = 'Crqi+khe6Ly6V8XJ8jZKhCLZABzRiYUVTMp45SoioII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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