SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0410614e691fb4f6f91d171ee7af2499e6c8320e6582f87ba96c9a25f84410b' 
  AND token = 'hvIC8R0pHbTjrRXksdBZuEFhVPBE7eOXLtPDHARl+oQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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