SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e33e845cb129fc734dda209dd52646e392213eb0d6661d00a40196ef89120208' 
  AND token = 'Wz38RCL/lGBTBR28pUt0qZCmtrPhodT6ynkscltKJ5Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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