SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9d1738adfd84c849c61789fa27d82533e6a75d25f1323999792c31d6189ade5c' 
  AND token = 'UuGXfvCz2yMxwYCPcOMFlSJLbOgiFc4L0plvec1PxJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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