SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd77bde72ae64071fc8f0b6dcb8d8d707ea0efbfded206e6fb7f7328738aeb94b' 
  AND token = 'iNKBEaeRopVCkX4qTTSbcRQHZRE0EIcKQtxxOnxZw9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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