SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fae16362283d0aa03ca105107d8960e756d87157d2e1e94cd933d94bc03d5155' 
  AND token = 'Eb+nwso7gs1y/+BoMQCr6+/Zp/UqvVFGNNchBYn1IDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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