SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ba5488914392c5164c05b800b1da766bfc2997481da1519f25d391f2992f153' 
  AND token = '2ougInqwfQl+lMy2rhtHadejSEYPo8XA8oSwzwC/eyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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