SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc7de783ab1e8dc0e55927114ace1f5be7c61bffe4f58639d313da9089b74598' 
  AND token = 'edgE1McztIZpFUmjnYdXmkyBFzMOM180FhnQQZEb9qk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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