SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '274d056284ba1f0f648687903aa693ca4ee767120219cce1d626af7103cdb9fa' 
  AND token = 'yBhAdS6OZRwJjnxjCe9wnzHkTDKbNXlWnQeKsNm05OM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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