SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd717ee331d84be6bbac9b9afbb6a3ea9062190a7b6f049db142ee211f6a445d1' 
  AND token = 'oCYavbjsDOzzDWQMCrXDWFzgNsH+87lZu79lJhbOeuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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