SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93dbd805adeea2a23e1f921adafcf709af44ff2f25956dda9848d506964d4bc4' 
  AND token = 'qapaz7CAE89JW0mVKisZHc/8gev6WLZEBlqBGrto3Vc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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