SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4a09fdd81c97f18cd129c6abece0e6ccf976b09fa0ff741fefe018ebf110926' 
  AND token = 'CwHj27IQxlChMTHig+88iCxhwcQDQrCv1XYQMsiQlVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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