SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3881f440e1c19b21a9a52433821c6469d1ba96380a34e26eeb25de54ff5942f5' 
  AND token = 'UlfDpyOTeXAdbaFZcgOXaMXNq1a/cNMs3OW6UnyVPKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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