SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '679e93ae8a450ed409aba0ebfa9bd868965db01f8a0dcd6f0447a4d63d41781e' 
  AND token = 'RTMLP0s4PssbR+TxwXDPToQolb+wLjqAdw8lDQq14YU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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