SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ccf186fe01a161ab4ad9687c8746454c35e498637dfa994686541f84902f496' 
  AND token = '0LF/1O8q8enwICpTqOFnaLpg12VZJFoRYNHYG3Pbxts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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