SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0baf79fa6fc4398835d7c148023c107c4a14dcd2c922569d1d347242a42795c3' 
  AND token = '/aXrRkIkFsu5Mmc/LibmNfMswmSOa4grjLur6KPOKyc=' 
  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"
    }
  }
}