SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a17c162161ef2c4bdeca257fa32ec0d6497ba2a58b4539607098bb15a1850644' 
  AND token = 'tz9ucw8chu2GnQhLOQg2WUYKlPVma9H10Gv2t2/3pec=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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