SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14607f7cbf7863fc4005baefd9ba1af3be6f178fb2428b0cce21fc758ef78903' 
  AND token = 'pnma/5tILyLGpatFCg15c0pzkWNcZ6/eR8Ry+00j5Gc=' 
  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"
    }
  }
}