SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1940ba68022bd3ccd23ab38a3bc5f88743c94170dfcc18043c5d118f99de6381' 
  AND token = 'gWBzgQul3TCd7cG5Itgef3ZJQ6ds0uTOO6q19Bau0iI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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