SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70cf292287020b0570885324a7ab6acf61f38079592832b973154383160cf60e' 
  AND token = 'CDf6PY+hzvOTLWS5yzXdeD4JkOEOdznAMKxbrCutBuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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