SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca9ba1f830eedbf8790548904bc0618f2bd8bef23bafcf80042b7a99e95157a3' 
  AND token = 'X4LQwgElEvstLfFouAMZzflG9Tz+smuqQY16Q70NFXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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