SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8eaf0aa30218e1fb1a1d4b241318f79ec7859433cf939a13d0eb88c7e1dc6e01' 
  AND token = 'GWlt8ukCoOODGZI4YUg+ul1l/IhPuefwONRGpV44+rE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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