SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f767a36ee5a895093918d69de1939709a437bc5becaf6c8df18adb7324ef626c' 
  AND token = 'tPbp7EDlo7BKHPSW/rl8arf/nDE2p3PodXBkAN5AXsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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