SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ba20d806ff73bdfd48be1b1c3149e98ac30f963774d40ed563632ca1bc41afd' 
  AND token = 'QRUMX0WLj5N+kT2Sck2vGguTNhOV3te2jMgk4+ooP9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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