SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '572f0ff14eb55fe3abaf5429cf29e2d83664c3f858321144e09502eb7b9893cf' 
  AND token = 'oqgYvCZHjWYJjKXGLFwpFi/A35sh2ubmfUmMS/4cljU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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