SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '72b8e09e212021c182f849794ef0a07427fedee53ef65f698f24d7908968284a' 
  AND token = 'fejgPMV0GSoREfiDsQDnaCoQ5wBhDgkKOezGZHxG4HA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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