SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e14544153dc6db70f79d8081da49e594d59b00e1d38fd1cbc30f89c99cfdaef8' 
  AND token = 'VKge9rkO4LMYSAfBpl5BjfSIlRb2JjNHqfs/NVE4gBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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