SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '045877c0ce08e2485b7b58514a203749b9e75694de1c8301e63522f91b26036a' 
  AND token = 'IjjFej8VpoFVmShyh17rpuPAtd8VZXV58SOHV4yhE5c=' 
  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"
    }
  }
}