SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1cf674cb5c887fc7107bed94bd02b39d1355929a68ac30c0c8fc93a2f6d5ce2b' 
  AND token = 'iTEwRN+G9qLCdYMQFV0KrylZvmlkMXqD+8g5NRxwW3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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