SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b833131a5180e62e5f9272cbdb0211296744047397b6df17b9b7675e76ea236e' 
  AND token = 'B+IOZ4QXVqAfJs8Jabxa+mnJ2Tk+iqS4uwsLCTICVHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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