SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4be8f0462faf79c154cf08f844edda9875d2b501fc8a2f99be8ca14d8ea3ada0' 
  AND token = 'gwqTQ6Jyxb7RKYJ0sG2Br9WHgWo2OGSJwrakmmYrln8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}