SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fac1d8dabaddca53a0a297e3c46ddb30399d141c0d9d98141d9ff22148690b2' 
  AND token = 'B/b7U2Eu6PfHFgKkZeG8QoaHoTbB6pYsxUxQ55v95d0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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