SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e0e15f88751f73b9603d7ed7458734b91fc4b717bc79147ba7fc220e44c8972' 
  AND token = 'wkOa42HjSydhzWcj+tGrYP/eAs3dXNL07+K2uxDSNlA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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