SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab953f5dda26857b230181fcfce9c02d4e848824dc9c2ae56e2c76a14b6d4888' 
  AND token = 'pts6xtPV3RZzZV+rlvTb77K4GVF+Ygii33o/xX7Aq+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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