SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a30d242356d15916191a5f2eea17df406f8037a5a9f183d604ba3d2b4d0fab0' 
  AND token = 'LJP6YDchiIzD/gRBP9b7cT2pF235vAfnvjVsGuLtNVE=' 
  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"
    }
  }
}