SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4712234ea64e7be2a173fbe5b354c927138e00553c5976430be2d812b2705b11' 
  AND token = 'Qay0XvO5TEhzLgrAJrTjwPPrHy3wDXa18ZuY2Viq4B0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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