SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ac19e5de5062fd7b0c630912ce0ff71a695257aca123ba9493e6c1743081e63' 
  AND token = 'zBLWz38xo68TpwOA9+eHrcJeYWQZhYPfshcA1ApZ+mE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}