SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd32f68eaf1d98dc87379e426b549bec646893da0fc135c1bd47072329d81586' 
  AND token = 'qE9jSxGTtJuHULO49vdcZPOkc6ZGOMpMfQm61/Lpxcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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