SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '322dafee6381a415a4115fb49e44534f07339774bcaeaaffe4250f247aa44a5c' 
  AND token = 'z6n0+DoLZCCajCTXpNyUwG5Ektw4nRASJwZuS4idgp4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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