SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b248dd80571c376e3a1297066f0d161629feb383ca40ae95743ab82f756fc613' 
  AND token = 'tkkaD9idHMW74hCjfaXpHEIETZnSY8zVvcV3cM3j4s8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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