SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddcee14bee5f461048b23baffe51ba0ea4e973b5882ae25abb707b971295d1fa' 
  AND token = 'gvyQM2QXEec4BUxpfYSuRhnJiyxja/G18TieSdQ13RU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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