SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da5f47e723715f070261ca231088b1a312d887bee07fe3c775e2bbd8aef6ce07' 
  AND token = 'SFO+C7xCW2kPGA+pSn9NUwHHH35Ju+Uqd3NfqjlHdgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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