SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00d402b536e546245a65c40c6f7ad9b413b8816a34cf197f1bd35688fac3a4b2' 
  AND token = 'LTO/V3kLFxHySJZzo+/jRhqS3ZKBLVmvZVy8r4IZeD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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