SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efdc814d7749708e9b1591972bebca36ca32fd069a6d2e18982be6bdfc48b3d6' 
  AND token = '3GopNC/o0z+3QwKhXIIDLXGjfrwGYO1hAhH1fV4vUzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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