SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb5a0ce52cd0ff526621531ca69e6050a8ca401896c3a09914830f732e4d404e' 
  AND token = '42EwWyp0Hxn+tYsFkrEsUznzagSWvMlveYmIM0W63PE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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