SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f37a6041120db9b4fb5e9271dc298fa202a4abbb6d4b0a5b3ecb7b1d33c18af' 
  AND token = '8gmA7E7moFAbNPitVEdwTawyDcDEU+ZMspNqu3YTNPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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