SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3472ffb502170d1736eb6c24ee73d53c446b7e0eddc1280b3c19b2d9b0b1015f' 
  AND token = 'C4WMqUnGjv+hKXePHbZB1b3utVacHWag0Cw3siaPj7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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