SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '58892967f0387707187dabb6b1b3614b4a9e0990f42e84fd4b6c8a286d8f7618' 
  AND token = 'HHjDslis28ujLWOpuCMaU9Cv2fy69pTg8BG4z/Eq8WI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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